Rishiraj Institute of Technology, Indore

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RISHIRAJ INSTITUTE OF TECHNOLOGY, INDORE REVTI GRAM, SAWER ROAD, INDORE-453331 MINNOR PROJECT ON E-WASTE RECYCLING IN INDIA SESSION 2009-2010 MECHANICAL ENGINEERING 2006-2010 RAJIV GANDHI PROUDYOGIKI VISHWAVIDYALAYA, BHOPAL GUIDED BY SUBMITTED BY 1 E-waste recycling in India

Transcript of Rishiraj Institute of Technology, Indore

Page 1: Rishiraj Institute of Technology, Indore

RISHIRAJ INSTITUTE OF TECHNOLOGY, INDOREREVTI GRAM, SAWER ROAD, INDORE-453331

MINNOR PROJECT ON

E-WASTE RECYCLING IN INDIA

SESSION 2009-2010

MECHANICAL ENGINEERING2006-2010

RAJIV GANDHI PROUDYOGIKI VISHWAVIDYALAYA, BHOPAL

GUIDED BY SUBMITTED BYH.O.D. S. B. DIGHE NITIN SINGHLECTURER R. MEHTA

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CONTENT

1.0. ABSTRAC

2.0. INTRODUCTION

3.0. DEFINITION

4.0. DESTINATION OF E-WASTE

5.0. INDIAN SCENARIO

6.0. THE STATUS

7.0. BASEL CONVENTION

8.0. E-TOXICS IN E-WASTE

8.1. E-WASTE AND ITS EFFECT ON HEALTH AND THE ENVIRONMENT

9.0. LIFE CYCLE OF E-WASTE

10.0. MANAGEMENT OF E-WASTES

10.1. INVENTORY MANAGEMENT

10.2. PRODUCTION-PROCESS MODIFICATION

10.3. VOLUME REDUCTION

10.4. RECOVERY AND REUSE

10.5. SUSTAINABLE PRODUCT DESIGN

11.0. WASTE MANAGEMENT CONCEPTS

11.1. RESOURCE RECOVERY

11.2. RECYCLING

11.3. WASTE MANAGEMENT TECHNIQUES

11.3.1. LANDFILL

11.3.2. INCINERATION

11.3.3. COMPOSTING AND ANAEROBIC DIGESTION

11.3.4. MECHANICAL BIOLOGICAL TREATMENT

11.3.5. PYROLYSIS & GASIFICATION

12.0. RECYCLING OF E-WASTE

12.1. RECYCLING/RECOVERY SYSTEM

12.2. BIFURCATION OF ELECTRONIC SCRAP

12.2.1. PRINTED CIRCUIT BOARDS (PCBS)

12.2.2. CHARACTERISTICS OF PCB SCRAP

12.2.3. DENSITY DIFFERENCES

12.2.4. MAGNETIC AND ELECTRICAL CONDUCTIVITY DIFFERENCES

12.2.5. POLYFORMITY

12.2.6. LIBERATION SIZE

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12.2.7. CHEMICAL REACTIVITY

12.2.8. ELECTROPOSITIVITY

12.3. DISASSEMBLY

12.4. MECHANICAL/PHYSICAL RECYCLING PROCESS

12.5. MECHANICAL APPROACHES OF RECYCLING ELECTRONIC SCRAP

12.6. HYDROMETALLURGICAL APPROACHES

12.7. EXTRACTION OF IC/ OTHER COMPONENTS FROM PCB

12.7.1. RECOVERY OF GOLD

12.7.2. MONITORS

12.7.2.1. Recovery of Glass from CRT

12.7.2.2. Yoke Core, Metallic Core and Copper from Transformers

12.7.2.3. Copper Extraction from Wires

12.7.2.4. Manual drawing of Wires for Copper

12.7.2.5. Plastic Shredding and Graining

12.7.2.6. Dismantling of compressor & segregation of compressor & cooling box

12.8. DISPOSAL

12.9. ADVANTAGES OF RECYCLING E-WASTE

13.0. RESPONSIBILITIES OF GOVERNMENT, INDUSTRIES, AND CITIZEN

13.1. RESPONSIBILITIES OF THE GOVERNMENT

13.2. RESPONSIBILITY AND ROLE OF INDUSTRIES

13.3. RESPONSIBILITIES OF THE CITIZEN

14.0. E-WASTE POLICY FOR INDIA

15.0. CONCLUSION

16.0. REFERENCES

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1. ABSTRACT

The production of electric and electronic equipment (EEE) is one of the fastest growing areas.This

development has resulted in an increase of waste electric and electronic equipment (WEEE).In view

of the environmental problems involved in the management of WEEE, many counties and

organizations have drafted national legislation to improve the reuse, recycling and other forms of

recovery of such wastes so as to reduce disposal. Recycling of WEEE is an important subject not

only from the point of waste treatment but also from the recovery of valuable materials.

"E-waste" is a popular, informal name for electronic products nearing the end of their "useful life.

"E-wastes are considered dangerous, as certain components of some electronic products contain

materials that are hazardous, depending on their condition and density. The hazardous content of

these materials pose a threat to human health and environment. Discarded computers, televisions,

VCRs, stereos, copiers, fax machines, electric lamps, cell phones, audio equipment and batteries if

improperly disposed can leach lead and other substances into soil and groundwater. Many of these

products can be reused, refurbished, or recycled in an environmentally sound manner so that they are

less harmful to the ecosystem. This paper highlights the hazards of e-wastes, the need for its

appropriate management and options that can be implemented.

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2. INTRODUCTION

Industrial revolution followed by the advances in information technology during the last century has

radically changed people's lifestyle. Although this development has helped the human race,

mismanagement has led to new problems of contamination and pollution. The technical prowess

acquired during the last century has posed a new challenge in the management of wastes. For

example, personal computers (PCs) contain certain components, which are highly toxic, such as

chlorinated and brominated substances, toxic gases, toxic metals, biologically active materials, acids,

plastics and plastic additives. The hazardous content of these materials pose an environmental and

health threat. Thus proper management is necessary while disposing or recycling ewastes.

These days computer has become most common and widely used gadget in all kinds of activities

ranging from schools, residences, offices to manufacturing industries. E-toxic components in

computers could be summarized as circuit boards containing heavy metals like lead & cadmium;

batteries containing cadmium; cathode ray tubes with lead oxide & barium; brominates flame

retardants used on printed circuit boards, cables and plastic casing; poly vinyl chloride (PVC) coated

copper cables and plastic computer casings that release highly toxic dioxins & furans when burnt to

recover valuable metals; mercury switches; mercury in flat screens; poly chlorinated biphenyl's

(PCB's) present in older capacitors; transformers; etc. Basel Action Network (BAN) estimates that

the 500 million computers in the world contain 2.87 billion kg of plastics, 716.7 million kg of lead

and 286,700 kg of mercury. The average 14-inch monitor uses a tube that contains an estimated 2.5

to 4 kg of lead. The lead can seep into the ground water from landfills thereby contaminating it. If

the tube is crushed and burned, it emits toxic fumes into the air.

Long-term exposure to deadly component chemicals and metals like lead, cadmium, chromium,

mercury and polyvinyl chlorides (PVC) can severely damage the nervous systems, kidneys and

bones, and the reproductive and endocrine systems, and some of them are carcinogenic and

neurotoxin. It is a generic term used to describe old, end-of-life electronic appliances such as

computers, laptops, TVs, DVD players, Mobile Phones, MP-3 players, etc., which have been

disposed of by their original users. Though there is no generally accepted definition of E-waste, in

most cases, E-waste comprises of relatively expensive and essentially durable products used for data

processing, tile-communications or entertainment in private house-holds and businesses.

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Public perception of E-waste is often restricted to a narrower sense, comprising mainly of end-of life

information and tile-communication equipment, and consumer electronics. However, technically

speaking, electronic waste is only a sub-set of WEEE (Waste Electrical & Electronic

Equipment). According to the Organization for Economic Cooperation & Development

(OECD), any appliance using an electric power supply that has reached its end-of-life would come

under WEEE. At macro-level, there are two ways to handle the E-Wastes: Disposal or Recycle /

Refurbish.

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3. DEFINITION

Electronic waste includes computers, entertainment electronics, mobile phones and Other items that

have been discarded by their original users. While there is no Generally accepted definition of

electronic waste, in most cases electronic waste Consists of electronic products that were used for

data processing, Telecommunications or entertainment in private households and businesses that are

now considered obsolete, broken, or un-repairable. Despite its common classification

as a waste, disposed electronics are a considerable category of secondary resource due to their

significant suitability for direct reuse, refurbishing, and material recycling of its constituent raw

materials. Re-conceptualization of electronic waste as a resource thus preempts its potentially

hazardous qualities.

Definition of electronic waste according to the WEEE directive :

· Large household appliances (ovens, refrigerators etc.)

· Small household appliances (toasters, vacuum cleaners etc.)

· Office & communication (PCs, printers, phones, faxes etc.)

· Entertainment electronics (TVs, HiFis, portable CD players etc.)

· Lighting equipment (mainly fluorescent tubes)

· E-tools (drilling machines, electric lawnmowers etc.)

· Sports & leisure equipment (electronic toys, training machines etc.)

· Medical appliances and instruments

· Surveillance equipment

· Automatic issuing systems (ticket issuing machines etc.)

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4. DESTINATION OF E-WASTE:

The waste is imported by over 35 countries, which include India, China, Pakistan, and Malaysia etc.

Fig. 1 shows the global E-waste traffic routes across Asia. The waste generated by the consumers of

electronic goods gets collected by scavengers or garbage collectors, and usually gets deported to

backyard stripping houses etc, where the potentially valuable substances are separated from the

waste and the residue, which may still contain many hazardous (or useful) substances, is dumped or

incinerated.

Fig-1 Asian E-Waste Traffic

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5. INDIAN SCENARIO

There is an estimate that the total obsolete computers originating from government offices, business

houses, industries and household is of the order of 2 million nos. Manufactures and assemblers in a

single calendar year, estimated to produce around 1200 tons of electronic scrap. It should be noted

that obsolesce rate of personal computers (PC) is one in every two years. The consumers find it

convenient to buy a new computer rather than upgrade the old one due to the changing

configuration, technology and the attractive offers of the manufacturers. Due to the lack of

governmental legislations on e-waste, standards for disposal, proper mechanism for handling these

toxic hi-tech products, mostly end up in landfills or partly recycled in a unhygienic conditions and

partly thrown into waste streams. Computer waste is generated from the individual households; the

government, public and private sectors; computer retailers; manufacturers; foreign embassies;

secondary markets of old PCs. Of these, the biggest sources of PC scrap are foreign countries that

export huge computer waste in the form of reusable components.

Electronic waste or e-waste is one of the rapidly growing environmental problems of the world. In

India, the electronic waste management assumes greater significance not only due to the generation

of our own waste but also dumping of e-waste particularly computer waste from the developed

countries.

With extensively using computers and electronic equipments and people dumping old electronic

goods for new ones, the amount of E-Waste generated has been steadily increasing. At present

Bangalore alone generates about 8000 tonnes of computer waste annually and in the absence of

proper disposal, they find their way to scrap dealers.

E-Parisaraa, an eco-friendly recycling unit on the outskirts of Bangalore which is located in

Dobaspet industrial area, about 45 Km north of Bangalore, makes full use of E-Waste. The plant

which is India’s first scientific e-waste recycling unit will reduce pollution, landfill waste and

recover valuable metals, plastics & glass from waste in an eco-friendly manner. E-Parisaraa has

developed a circuit to extend the life of tube lights. The circuit helps to extend the life of fluorescent

tubes by more than 2000 hours. If the circuits are used, tube lights can work on lower voltages. The

initiative is to aim at reducing the accumulation of used and discarded electronic and electrical

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equipments.

India as a developing country needs simpler, low cost technology keeping in view of maximum

resource recovery in an environmental friendly methodologies. E-Parisaraa, deals with practical

aspect ofe-waste processing as mentioned below by hand. Phosphor affects the display resolution

and luminance of the images that is seen in the monitor.

E-Parisaraa’s Director Mr. P. Parthasarathy, an IIT Madras graduate, and a former consultant for a

similar e-waste recycling unit in Singapore, has developed an eco-friendly methodology for reusing,

recycling and recovery of metals, glass & plastics with non-incineration methods . The hazardous

materials are segregated separately and send for secure land fill for ex.: phosphor coating, LED’s,

mercury etc.

We have the technology to recycle most of the e-waste and only less than one per cent of this will be

regarded as waste, which can go into secure landfill planned in the vicinity by the HAWA project.

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6. THE STATUS

The first comprehensive study to estimate the annual generation of E-waste in India and answer the

questions above is being under taken up by the National WEEE Taskforce. The preliminary

estimates suggest that total WEEE generation in India is approximately 1,46,000 tonne per year.

The top states in order of highest contribution to WEEE are:-

1.Maharashtra, 2.Andhra Pradesh, 3.Tamil Nadu, 4. Uttar Pradesh,

5.West Bengal, 6.Delhi, Karnataka, 7.Gujarat, 8.Madhya Pradesh, and

9.Punjab.

The city-wise ranking of largest WEEE generators are:-

1.Mumbai, 2.Delhi, 3.Bangalore, 4.Chennai, 5.Kolkatta, 6.Ahmedabad,

7.Hyderabad, 8.Pune, 9.Surat, and 10.Nagpur.

An estimated 30,000 computers become obsolete every year from the IT industry in Bangalore

alone simply due to an extremely high obsolescence rate of 30 per cent per annum.

Almost 50 per cent of the PCs sold in India are products from the secondary market and are re-

assembled on old components. The remaining market share is cover by multinational-manufacturers

(30 per cent), and Indian brands (20 per cent). Three categories of WEEE account for almost 90 per

cent of the generation - Large Household Appliances (42 per cent), Information & Communications

Technology Equipment (34 per cent), Consumer Electronics (14 per cent).

The E-waste recycled by the formal recyclers is done under environmentally sound practices which

ensure that damage is minimized to the environment. They also adopt processes so that the

workforce is not exposing to toxic and hazardous substances released during recycling process. But

they cannot match either the reach or the network of the informal recyclers used for sourcing of old

electrical and electronic items from business as well as individual households.

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The items are collect, segregated and the informal recyclers further dismantle the ones that cannot be

sold as it is. The final step is recycling which is mainly manual using simple tools like hammer,

screw driver, etc., and by the use of rudimentary techniques like burning of wires in the

open, using acid bath for extraction of precious metals.

Furthermore, these activities are carried out without wearing any protective gear like masks, gloves,

etc. In the absence of suitable processes and protective measures, recycling E-waste results in toxic

emission to the air, water, soil and poses serious environmental and health hazards. Thus, the

challenges are manifold: environmental and health hazards; lack of awareness amongst various

stakeholders including public at large; investment required for setting up of state-of-the-art waste

management facilities; monitoring and reporting of the E-waste generated; and most importantly,

reconciling technological advancement with sustainable development.

E-WASTE SITUATION IN INDIA

At present, the e-waste management system in India is characterised by a market driven collection

and recycling implying no direct cost to consumers, producers or taxpayers. The system is

dominated by the informal sector in backyard workshops . Backyard workshops are considered being

a part of the informal economy. Informal and underground economy is defined by Frey and

Schneider (2000): “It comprises all presently not recorded productive (i.e. value-adding) activities

which should be in the national product (GNP).” In this thesis the informal scrap industry is seen as

recycling facilities that do not comply with state regulations regarding taxation, environmental

protection or safety standards (Streicher-Porte, 2006). Up to now no regulations or controls on

material or financial flows, standards of emissions or occupational hazards have been implemented

(Sinha, 2004). Though India signed the Basel Convention, there is no specific legislation regulating

the export or the collection and treatment of E-waste. There are however several existing

environmental legislations which are of importance and useful in the context of E-waste. India is one

of the countries that have to deal with the arising load of E-waste. Figure 2 indicates that the PC

growth per capita in India had been over 1’000 % between 1993 and 2000. From 2002 to 2004 the

sales of computers in India almost doubled as a market study shows, which had been performed in

22 Indian cities (see Figure 2).

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Fig 2. Top scoring countries in PC growth rates (left) and penetration rates (right) (Schwarzeret al., 2005).

Since the growth of PC sales correlates with the generation of E-waste (Jain and Sareen, 2006) these

sales implicate a massive increase of E-waste. As an outcome of Phase I of seco’s global E-waste

programme the Indo-German-Swiss Initiative for E-waste management had been set up. It brings

together the experience and expertise of all the partners (MoEF, GTZ, seco) involved. The partners

work in close collaboration with manufacturers, users, recyclers, and NGOs to develop a sustainable

e-waste management system in India (e-Waste Guide India, 2006).

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Fig 3. PC market trends in India from 1997 to 2004 (BIRD, 2005).

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7. BASEL CONVENTION

The fundamental aims of the fundamental aims of the Basel Convention are the control and

reduction of trans-boundary movements of hazardous and other wastes including the prevention and

minimization of their generation, the environmentally sound management of such wastes and the

active promotion of the transfer and use of technologies.

A Draft Strategic Plan has been proposed for the implementation of the Basel Convention. The Draft

Strategic Plan takes into account existing regional plans, program or strategies, the decisions of the

Conference of the Parties and its subsidiary bodies, ongoing project activities and process of

international environmental governance and sustainable development. The Draft requires action at

all levels of society: training, information, communication, methodological tools, capacity building

with financial support, transfer of know-how, knowledge and sound, proven cleaner technologies

and processes to assist in the concrete implementation of the Basel Declaration. It also calls for the

effective involvement and coordination by all concerned stakeholders as essential for achieving the

aims of the Basel Declaration within the approach of common but differentiated responsibility.

Are the control and reduction of trans-boundary movements of hazardous and other wastes including

the prevention and minimization of their generation, the environmentally sound management of such

wastes and the active promotion of the transfer and use of technologies?

A set. of interrelated and mutually supportive strategies are proposed to support the concrete

implementation of the activities as indicated is described below:

1. To involve experts in designing communication tools for creating awareness at the highest

level to promote the aims of the Basel Declaration on environmentally sound management

and the ratification and implementation of the Basel Convention, its amendments and

protocol with the emphasis on the short-term activities.

2. To engage and stimulate a group of interested parties to assist the secretariat in exploring

fund raising strategies including the preparation of projects and in making full use of

expertise in non-governmental organizations and other institutions in joint projects.

3. To motivate selective partners among various stakeholders to bring added value to making

progress in the short-term.

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4. To disseminate and make information easily accessible through the internet and other

electronic and printed materials on the transfer of know-how, in particular through Basel

Convention Regional Centers (BCRCs).

5. To undertake periodic review of activities in relation to the agreed indicators;

6. To collaborate with existing institutions and program to promote better use of cleaner

technology and its transfer, methodology, economic instruments or policy to facilitate or

support capacity-building for the environmentally sound management of hazardous and other

wastes.

The Basel Convention brought about a respite to the trans-boundary movement of hazardous waste.

India and other countries have ratified the convention. However United States (US) is not a party to

the ban and is responsible for disposing hazardous waste, such as, e-waste to Asian countries even

today. Developed countries such as US should enforce stricter legislations in their own country for

the prevention of this horrifying act.

In the European Union where the annual quantity of electronic waste is likely to double in the next

12 years, the European Parliament recently passed legislation that will require manufacturers to take

back their electronic products when consumers discard them. This is called Extended Producer

Responsibility. It also mandates a timetable for phasing out most toxic substances in electronic

products.

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8. E-TOXICS IN E-WASTE

"Printed Circuit Boards contain heavy metals such as Antimony, Silver, Chromium, Zinc, Lead, Tin

and Copper. According to some estimates there is hardly any other product for which the sum of the

environmental impacts of raw material, extraction, industrial, refining and production, use and

disposal is as extensive as for printed circuit boards."

"In short, the product developers of electronic products are introducing chemicals on a scale which is

totally incompatible with the scant knowledge of their environmental or biological characteristics."

TABLE-1 Material used in a desktop computer and the efficiency of current

recycling processes

Name content (% of

total weight)

Recycling

Efficiency %

Weight of

material (lb)

Use/Location

Plastics 22.9907 13.8 20 Includes organics, oxides

other than silica

Lead 6.2988 3.8 5 Metal joining, radiation

shield/CRT, PWB

Aluminum 14.1723 8.5 80 Structural,

conductivity/housing,

CRT,PWB, connectors

Germanium 0.0016 < 0.1 0 Semiconductor/PWB

Gallium 0.0013 < 0.1 0 Semiconductor/PWB

Iron 20.4712 12.3 80 Structural,

magnetivity/(steel) housing

CRT, PWB

Tin 1.0078 0.6 70 Metal joining/PWB, CRT

Copper 6.9287 4.2 90 Conductivity/CRT, PWB,

connectors

Barium 0.0315 < 0.1 0 In vacuum tube/CRT

Nickel 0.8503 0.51 80 Structural,

magnetivity/(steel) housing,

CRT, PWB

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Zinc 2.2046 1.32 60 Battery, phosphor

emitter/PWB, CRT

Tantalum 0.0157 < 0.1 0 Capacitors/PWB, power

supply

Indium 0.0016 < 0.1 60 Transistor, rectifiers/PWB

Vanadium 0.0002 < 0.1 0 Red phosphor emitter/CRT

Terbium 0 0 0 Green phosphor activator,

dopant /CRT, PWB

Beryllium 0.0157 < 0.1 Thermal conductivity/PWB,

connectors

Gold 0.0016 < 0.1 99 Connectivity,

conductivity/PWB,

connectors

Europium 0.0002 < 0.1 0 Phosphor activator/PWB

Titanium 0.0157 < 0.1 0 Pigment, alloying

agent/(aluminum),housing

Ruthenium 0.0016 < 0.1 80 Resistive circuit/PWB

Cobalt 0.0157 < 0.1 85 Structural, magnetivity

/(steel) housing, CRT, PWB

Palladium 0.0003 < 0.1 95 Connectivity,

conductivity/PWB,

connectors

Manganese 0.0315 < 0.1 0 Structural,

magnetivity/(steel) housing,

CRT, PWB

Silver 0.0189 < 0.1 98 Conductivity/PWB,

connectors

Antinomy 0.0094 < 0.1 0 Diodes/housing, PWB, CRT

Bismuth 0.0063 < 0.1 0 Wetting agent in thick

film/PWB

Chromium 0.0063 < 0.1 0 Decorative, hardener/(steel)

housing

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Cadmium 0.0094 < 0.1 0 Battery, glu-green phosphor

emitter/housing, PWB, CRT

Selenium 0.0016 0.00096 70 Rectifiers/PWB

Niobium 0.0002 < 0.1 0 welding allow/housing

Yttrium 0.0002 < 0.1 0 Red phosphor emitter/CRT

Rhodium 0 50 thick film conductor/PWB

Platinum 0 95 Thick film conductor/PWB

Mercury 0.0022 < 0.1 0 Batteries, switches/housing,

PWB

Arsenic 0.0013 < 0.1 0 Doping agents in

transistors/PWB

Silica 24.8803 15 0 Glass, solid state

devices/CRT,PWB

E-waste and its effect on health and the environment

E-waste cannot be considered or treated like any kind of waste, because it contains hazardous and

toxic substances such as lead, mercury, cadmium or others such as dioxins and furans, bromined

flame retardants (produced when e-waste is incinerated). For instance, lead represents 6% of the total

weight of a computer monitor. Another example: nearly 36 chemical elements are

Incorporated in electronic equipment. This data further demonstrates the un-sustainability of

irresponsible electronic equipment disposal, its negative effect on the environment and the need to

implement management regulations which include actions like refurbishment and recycling.

Even though in the last years recycling has become a regular practice almost everywhere in the

world, some e-waste components present difficulties when they are recycled mainly because of their

complexity and the lack of methods. Such is the case of plastics used in electronic equipment which

contain flame retardants that impede the recycling process. In order to amplify the information

submitted in the web page “We Re-cycle” following is a more detailed description of electronic

equipment components effects on human health and the environment.

Table-2 Products and Health Effects of E-Waste

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name of

chemicals

Characteristics Effects on Humans Impacts on the

Environment

Polychlorinated

Biphenyl (PCB)

Can be present in

condensers and

transformers of old

electronic

equipment because of

its properties as cooler,

lubricant and its

resistance to high

temperatures.

Humans are exposed

through contaminated

food consumption or

direct contact at their

workplace,

(e.g inadequate

disassembly of electronic

equipment). Exposure to

this compound can cause

anemia, damages to the

skin, liver, stomach and

thyroid. Contamination of

pregnant women is very

risky and research results

show that it can be

carcinogen

This chemical compound

could drip through

subsurface layers reaching

water and contaminating

it if buried in landfills.

Because it is poorly

soluble, it is very

dangerous when it enters

water currents as it could

contaminate the chain of

production of some foods.

Tetra Bromo

Bisphenol-A

(TBBPA)

TBBA is a flame-

retardant, which is

use in computer

motherboards. This

compound represents

50% of all

bromined flame-

retardants produced

worldwide. 96% of all

motherboards

use this chemical

compound which

represents 1 to 2% of

their weight

It has not been prove that

it can cause mutations or

carcinogen effects on

human beings.

Nevertheless, it has been

prove that TBBA may

interfere in the transport

and metabolism of some

hormones. A technical

study has demonstrated

that there is a direct

correlation between TBBA

in the blood flow and in

the air. TBBA is toxic to

Unlike other flame-

retardants, TBBA when

used as a reactive, bounds

chemically to plastic or

polymers for protection.

This impedes its liberation

into the environment. It is

biodegradable but one of

the products of this

biodegradation is

bisphenol, which can

cause damages to the

endocrine system. The

fact that TBBA dissolves

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aquatic organisms poorly in water and tends

to adhere to soil, where it

can reach food, has

created great concern

because TBBA levels

magnify while passing

through the food chain

from 20 to 3200 times.

Polybrominated

Biphenyls (PBB)

Originally, this

substance was add to

plastics of electronic

equipment for

inflammability

reduction. Nevertheless,

PBB production in the

US was stop in 1976 and

in the world in 2000.

Exposure to this

substance can damage

kidneys, liver and

thyroids. Fetuses that

were expose to PBB had

endocrinal problems.

Likewise it is suspected

that PBB is carcinogen

PBB dissolves poorly in

water but can

adhere strongly to soil,

through which it could

reach food. It keeps

magnifying while passing

along the food chain.

Polybrominated

Diphenyl Ethers

(PBDE)

PBDE is another

brominates flame-

retardant with its

number of bromine

atoms varying up to 209

times. Three types are

sold for commercial use

referred to as pent, octa

and deca, two of them

used in electronic

equipment: octa, used

in high impact housings,

and deca used in wire

insulation. Even though

the production of this

Since it was tested for the

first time in 1970, PBDE

was found in numerous

samples of human tissue,

and with increasing

concentrations of factor

100 in the last 30 years.

Exposure can occur the

moment that plastics

containing this substance

are recycled. Concerns for

human health arise

because PBDE containing

4 to 6 brominated

molecules that can act as

PDBE is easily liberated

into the

environment and, like

other flameretardants,

dissolves poorly in water

and strongly adheres to

soil, crossing to

organisms, animals, and

food. This crossing

depends on the

brominated concentration

level; the lower it is, the

more toxic PDBE gets (for

example when exposed to

UV Light). This compound

21 E-waste recycling in India

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compound has

decreased since 1999 its

presence in the

environment is

increasing, becoming a

global problem.

thyroxin, damaging the

endocrine system.

Exposed children show

thyroid damages and

neurological anomalies.

is almost omnipresent, as

it is found both in sea and

fresh water organisms,

mammals, birds and water

and soil samples. When

PBDE is incinerated, it

produces dioxins and

furans.

Chlorofluorocarb

ons (CFC)

CFC are used in aerosol

propellants,

cleansing agents,

foaming agents, and

other packaging

materials like solvents

and refrigerants. In

1987, a prohibition

campaign was initiated

reaching its

objective in 1996, an

objective that

developing countries

aim to reach in

2010.

There are no significant

impacts on human health.

Nevertheless there are

indirect negative effects.

Fir example, the release

of CFC attacks levels of

the atmosphere

When in contact with the

ozone layer, CFC destroys

it. One chlorine atom is

responsible for the

destruction of 100.000

ozone molecules. The

ozone layer protects earth

from radiation which

causes skin cancer and

blindness in living beings

Polyvinyl chloride

(PVC)

PVC plastic is used as an

insulator in

certain types of wiring in

electronic

equipment. Risks arise

from vinyl

chloride since this

compound is toxic and

the DEHP used to soften

In the amounts present in

the environment, there is

no proof that DEHP

causes damage to humans

beings but it been proven

that it can damage to lab

animal kidneys. Recent

debates about this

compound suggest that it

This compound is

disseminated in the

environment because of

its extended usage, being

soluble in water if oils or

grease are present. Bonds

easily with soil but also

degrades easily in contact

with

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PVC

carries great risks to

human health

can cause endocrine and

gender anomalies in

embryos

oxygen.

Arsenic (As) Arsenic is present in

small amounts

inelectronic equipment

in forms such as Gallium

Arsenide Gas, which

hassemiconductor

properties and can

befound in electronic

equipment diodes.

Gas is carcinogen and

causes skin and lung

cancers. The most

common means of

exposure is direct contact

with dust containing this

compound especially by

workers of semiconductor

manufacturers.

Gallium Arsenide is an

inorganic compound with

low water solubility. It is

transformed into an

organic compound when

bio-accumulated in fish

and crustaceans.

Barium (Ba) Barium is generally use

in cathode

ray tubes (CRT) in

computer monitors.

When functioning in the

monitor this

metal reacts with CO,

CO2, N2, O2,

H2O y H2 which

produces a series of

barium compounds

including oxides,

hydroxides and

carbonates.

Barium compounds’

toxicity is link to its

solubility in water. Some

of these compounds

produced in monitors are

extremely soluble. Intake

of these compounds can

cause gastrointestinal

disorders and muscle

weakness. Higher doses

can cause changes in

heart beat rate, paralysis

and death. Direct contact

with dust containing

barium can cause eye and

skin irritation.

Its impact on the

environment depends on

its solubility. Barium

compounds that are

highly soluble in water are

very mobile and tend to

cumulate in aquatic

organisms

Beryllium (Be) Beryllium is a metal that

generally

forms alloys with copper

to increase its

Beryllium is only

dangerous if inhaled, as

dust or fumes, which

could occur when

This metal doesn’t

dissolve in water and it

remains into soil

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endurance, conductivity

and elasticity. Initially,

Beryllium was used in

the production of

motherboards but its

major usage is in

contact circuits,

relays and in some laser

printer

mechanisms

electronic equipment is

disassembled, burned or

crushed. Its inhalation can

cause pneumonia,

respiratory inflammation

(chronic illness of

Beryllium) and can raise

the risk of lung cancer

Cadmium (Cd) Cadmium is a heavy

metal included in many

electronic components,

such as

contact plates, switches,

or used to

prevent corrosion.

Cadmium is particularly

found in chip resistors,

infrared detectors, and

semiconductors. Old

monitors contain

around 5 to 10 grams of

Cadmium and some

batteries are made of

Nickel Cadmium. It is

added as a plastic

stabilizer and pigment

to wiring,

motherboards, pcs,

monitors and printed

circuit boards.

Cadmium exposure

commonly occurs through

inhalation and ingestion

of food or contaminated

water. Inhaling large

amounts of Cadmium can

cause lung damage and

death. Exposure to small

amounts over a long

period of time can cause

high pressure and kidney

damage. This metal is

arcinogen.

Cadmium enters the

environment through

water and soil that is

absorbed by plants. Low

concentrations can cause

alterations in the ecology

and balance of soil

nutrients. This metal can

bio-accumulate in

mushrooms, oysters,

shrimps, mussels and fish.

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Chromium VI

(Cr+6)

Chromium VI, i.e.

chromium ions with a

charge of +6, is

chromium’s only toxic

form. Its presence is

small in electronic

equipment where it is

used as a plastic

hardener and protection

layer for some metal

components. When

electronic components

are burned, 99% of

Chromium VI stays in

residuals and ashes,

contaminating soil in a

toxic way, which could

reach water currents

with significant higher

risk.

The effect of this

compound on humans

depends on the type of

exposure. For example,

inhalation can cause

catarrh, nose bleeding,

ulcers and sinus

perforations. Ingestion of

contaminated water and

food can damage the

stomach, kidneys, liver

and cause ulcers,

convulsions and even

death. If there is a direct

contact with skin it can

cause ulcers. This metal is

carcinogen only when

inhaled.

Chromium VI is hardly

found in nature. Its

presence in the

environment (air) is

attributed to industrial

plant emissions, fuel

combustion in commercial

and residential zones.

Lead (Pb) Lead is found in many

electronic

equipment components.

For example,

in a PC, the largest

amount of this

metal is found in the

CRT of the

monitor: 0 to 3% in the

panel, 70% in

the frit, 24% in the

funnel and 30% in the

Humans are exposed to

this metal by particle

inhalation and through

contaminated foods. The

first effects and symptoms

of lead exposure are

anorexia, muscle pain,

malaise and headache but

an extended exposure can

cause a decrease in

nervous system

performance, weakness,

The chemical structure of

this metal is directly

affected by its pH but

most lead compounds are

insoluble in water and

remain in that state. They

are difficultly accumulated

in plants or transferred to

food. Lead doesn’t bio-

accumulate in fish but it

does in other seafood. If

broken or incinerated to

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neck. Lead is also

present in

weldings (40%),

motherboards, circuits

and wiring plastic.

brain damage and even

death. Likewise, it can

affect the reproductive

system both in men and

women and is considered

carcinogen.

the environment, particles

will be transmitted by air

and soil.

Lithium (Li) Lithium is present in

computer batteries and

modern electronic

equipment. Typically

batteries contain an

anode of lithium or

lithium oxide, a

magnesium dioxide

(magnesium oxide and

carbon) cathode and

lithium salt dissolved in

an organic solvent. This

type of batteries

replaces alkaline and

NiCd batteries. It is

environmentally more

sustainable than its

predecessors.

Lithium doesn’t cause

toxicological problems as

lead, cadmium or mercury

do. But, a great risk exists

for workers that have a

direct contact. Lithium is

classified as a corrosive

alkali that can burn skin,

eyes and, if inhaled, lungs.

To avoid these risks

lithium batteries must not

be exposed to hot

environments or broken,

factors that can cause the

battery to explode.

Not many studies about

the effects oflithium on

the environment have

beenpublished. These

compounds tend to stay

dissolved in water and

they aren’t easily

absorbed through soil.

Mercury (Hg) Mercury is found in

three specific

places in a computer.

The largest

amount is found in LCD

screen

fluorescent light,

computer or monitor

All forms of mercury

represent a risk to human

health, but mercury in

metal form that is not

combined with other

components and organic

methyl mercury are the

ones that possess the

The impact of mercury on

the environment has been

thoroughly studied.

Mercury in pure form is

extremely volatile and

mining, incineration and

manufacture release this

compound to the

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switches, which enable

them to shut

down while idle, and

finally in batteries.

Mercury is very volatile

and easily liberated by

incineration or breaking,

which could liberate up

to 90% of the mercury

contained in the

monitor screen, for

example.

greater risk, especially to

the nervous system.

Short-term exposures to

this compound cause lung

damage, nausea,

vomiting, diarrhea, high

pressure, and, skin and

eye irritation. Long or

permanent exposure

might cause permanent

damages to the brain,

kidneys and fetus

development, besides

neurological changes,

irritability, tremors, short-

sightedness, deafness,

memory problems,

delirium, hallucinations

and suicidal tendencies.

atmosphere. When

mercury, in any of its

forms, gets in contact with

water or soil, turns into

organic methyl mercury

by bacteria action. In

organic form mercury is

more accessible to living

organisms and food. Many

studies have shown

mercury presence in fish,

causing great concern in

many regions worldwide.

Níckel (Ni) Nickel is present in the

batteries of

some electronic

equipment (NiCd),

which are being

gradually replaced

with lithium batteries.

Likewise, nickel

is used in CRT of

computer monitors

Nickel causes skin

damages and asthma

symptoms in about 10 to

20% of the population

that has direct contact.

Workers that are exposed

to dust containing nickel

suffer bronchitis and lung

damages. There is

evidence that many nickel

compounds such as nickel

hydroxide are carcinogen

Nickel generally enters the

environment through air.

These particles are then

placed in water and soil,

especially if they contain

magnesium and steel.

Nevertheless, this

compound does not bio-

accumulate in living

organisms.

Antimony (Sb) Antimony is present in Elevated exposure to Antimony released into

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electronic

equipment in small

quantities.

Antimony trioxide is

added to plastic as a

flame-retardant. This

compound is also used

in the CRT glass of

monitors and wire

welding.

antimony via electronic

equipment is unlikely.

Experiments in animals

have emonstrated that

short-term exposure can

cause eye and skin

irritation, hair loss, lung

and heart damages, and

fertility problems.

Antimony trioxide is

considered as possibly

carcinogen

the environment is

commonly found in soil

and sediments. Its

mobility greatly depends

on soil structure, the form

which it takes, and its pH.

This element is better

absorbed in soils

containing steel,

magnesium or aluminum.

Zinc Sulfide (ZnS) Zinc Sulfide is mixed

with other metals

to create a phosphor

coating, which is

used in the inside of the

monitor glass.

Exposure to this

compound happens

when the monitor

breaks.

This element is corrosive

to the skin and lungs and

its ingestion can be very

harmful because it forms

a toxic gas (hydrogen

sulfide) within the

stomach

Zinc is one of the most

common minerals in

nature.

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9. Life Cycle of E-waste.

To ensure proper and nearly complete collection of used electronic equipments after they are

rendered useless, it is important to study the processes, which the equipment has undergone. That is

to say, the study of the life cycle of the equipment is equally relevant. The Fig. 5 shows the life span

of electronic equipments, taking into account that it may have switched users during the course of its

operational life. This course will have to be considered for effective collection so that maximum or

all of the E-Waste can be recycled.

For instance, computer hardware would appear to have up to 3 distinct product lives: the original life

or first product life (when it is being used by the primary user) and up to 2 further lives depending on

reuse. Fig. 5 depicts the flow of computer hardware units from point-of-sale to the original purchaser

and on to the reuse phases. The duration of the product’s first life is estimated to be between 2 and 4

years for corporate users and between 2 and 5 years for domestic users. The life cycle of computer

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waste is defined as, the period from when it is discarded by the primary user to when it goes for

recycling or is disposed of in a landfill.

Product manufacturer

Material recycling

Primary user second user third/fourth user landfill

Fig-4Flow of E-waste During Its Life Cycle

10. MANAGEMENT OF E-WASTES

It is estimated that 75% of electronic items are stored due to uncertainty of how to manage it. These

electronic junks lie unattended in houses, offices, warehouses etc. and normally mixed with

household wastes, which are finally disposed off at landfills. This necessitates implementable

management measures.

In industries management of e-waste should begin at the point of generation. This can be done by

waste minimization techniques and by sustainable product design. Waste minimization in industries

involves adopting:

inventory management,

production-process modification,

volume reduction,

recovery and reuse.

10.1.Inventory management

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Proper control over the materials used in the manufacturing process is an important way to reduce

waste generation (Freeman, 1989). By reducing both the quantity of hazardous materials used in the

process and the amount of excess raw materials in stock, the quantity of waste generated can be

reduced. This can be done in two ways i.e. establishing material-purchase review and control

procedures and inventory tracking system.

Developing review procedures for all material purchased is the first step in establishing an inventory

management program. Procedures should require that all materials be approved prior to purchase. In

the approval process all production materials are evaluated to examine if they contain hazardous

constituents and whether alternative non-hazardous materials are available.

Another inventory management procedure for waste reduction is to ensure that only the needed

quantity of a material is ordered. This will require the establishment of a strict inventory tracking

system. Purchase procedures must be implemented which ensure that materials are ordered only on

an as-needed basis and that only the amount needed for a specific period of time is ordered.

Production-process modification

Changes can be made in the production process, which will reduce waste generation. This reduction

can be accomplished by changing the materials used to make the product or by the more efficient use

of input materials in the production process or both. Potential waste minimization techniques can be

broken down into three categories:

i) Improved operating and maintenance procedures,

ii) Material change and

iii)Process-equipment modification.

Improvements in the operation and maintenance of process equipment can result in significant waste

reduction. This can be accomplished by reviewing current operational procedures or lack of

procedures and examination of the production process for ways to improve its efficiency. Instituting

standard operation procedures can optimise the use of raw materials in the production process and

reduce the potential for materials to be lost through leaks and spills. A strict maintenance program,

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which stresses corrective maintenance, can reduce waste generation caused by equipment failure. An

employee-training program is a key element of any waste reduction program. Training should

include correct operating and handling procedures, proper equipment use, recommended

maintenance and inspection schedules, correct process control specifications and proper

management of waste materials.

Hazardous materials used in either a product formulation or a production process may be replaced

with a less hazardous or non-hazardous material. This is a very widely used technique and is

applicable to most manufacturing processes. Implementation of this waste reduction technique may

require only some minor process adjustments or it may require extensive new process equipment.

For example, a circuit board manufacturer can replace solvent-based product with water-based flux

and simultaneously replace solventvapor degreaser with detergent parts washer.

Installing more efficient process equipment or modifying existing equipment to take advantage of

better production techniques can significantly reduce waste generation. New or updated equipment

can use process materials more efficiently producing less waste. Additionally such efficiency

reduces the number of rejected or off-specification products, thereby reducing the amount of

material which has to be reworked or disposed of. Modifying existing process equipment can be a

very cost-effective method of reducing waste generation. In many cases the modification can just be

relatively simple changes in the way the materials are handled within the process to ensure that they

are not wasted. For example, in many electronic manufacturing operations, which involve coating a

product, such as electroplating or painting, chemicals are used to strip off coating from rejected

products so that they can be recoated. These chemicals, which can include acids, caustics, cyanides

etc are often a hazardous waste and must be properly managed. By reducing the number of parts that

have to be reworked, the quantity of waste can be significantly reduced.

Volume reduction

Volume reduction includes those techniques that remove the hazardous portion of a waste from a

non-hazardous portion. These techniques are usually to reduce the volume, and thus the cost of

disposing of a waste material. The techniques that can be used to reduce waste-stream volume can be

divided into 2 general categories: source segregation and waste concentration. Segregation of wastes

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is in many cases a simple and economical technique for waste reduction. Wastes containing different

types of metals can be treated separately so that the metal value in the sludge can be recovered.

Concentration of a waste stream may increase the likelihood that the material can be recycled or

reused. Methods include gravity and vacuum filtration, ultra filtration, reverse osmosis, freeze

vaporization etc.

For example, an electronic component manufacturer can use compaction equipments to reduce

volume of waste cathode ray-tube.

Recovery and reuse

This technique could eliminate waste disposal costs, reduce raw material costs and provide income

from a salable waste. Waste can be recovered on-site, or at an off-site recovery facility, or through

inter industry exchange. A number of physical and chemical techniques are available to reclaim a

waste material such as reverse osmosis, electrolysis, condensation, electrolytic recovery, filtration,

centrifugation etc. For example, a printed-circuit board manufacturer can use electrolytic recovery to

reclaim metals from copper and tin-lead plating bath.

However recycling of hazardous products has little environmental benefit if it simply moves the

hazards into secondary products that eventually have to be disposed of. Unless the goal is to redesign

the product to use nonhazardous materials, such recycling is a false solution.

Sustainable product design

Minimization of hazardous wastes should be at product design stage itself keeping in mind the

following factors*

Rethink the product design: Efforts should be made to design a product with fewer amounts

of hazardous materials. For example, the efforts to reduce material use are reflected in some

new computer designs that are flatter, lighter and more integrated. Other companies propose

centralized networks similar to the telephone system.

Use of renewable materials and energy: Bio-based plastics are plastics made with plant-

based chemicals or plant-produced polymers rather than from petrochemicals. Bio-based

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toners, glues and inks are used more frequently. Solar computers also exist but they are

currently very expensive.

Use of non-renewable materials that are safer: Because many of the materials used are non-

renewable, designers could ensure the product is built for re-use, repair and/or

upgradeability. Some computer manufacturers such as Dell and Gateway lease out their

products thereby ensuring they get them back to further upgrade and lease out again.

11. Waste management concepts:

The waste hierarchies there are a number of concepts about waste management, which vary in their

usage between countries or regions. The waste hierarchy:

reduce

reuse

recycle

Classifies waste management strategies according to their desirability. The waste hierarchy has

taken many forms over the past decade, but the basic concept has remained the cornerstone of most

waste minimization strategies. The aim of the waste hierarchy is to extract the maximum practical

benefits from products and to generate the minimum amount of waste. Some waste management

experts have recently incorporated a 'fourth R': "Re-think", with the implied meaning that the present

system may have fundamental flaws, and that a thoroughly effective system of waste management

may need an entirely new way of looking at waste.

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Some "re-think" solutions may be counter-intuitive, such as cutting fabric patterns with slightly

more "waste material" left -- the now larger scraps are then used for cutting small parts of the

pattern, resulting in a decrease in net waste. This type of solution is by no means limited to the

clothing industry. Source reduction involves efforts to reduce hazardous waste and other materials

by modifying industrial production.

Source reduction methods involve changes in manufacturing technology, raw material inputs, and

product formulation. At times, the term "pollution prevention" may refer to source reduction.

Another method of source reduction is to increase incentives for recycling. Many communities in the

United States are implementing variable rate pricing for waste disposal (also known as Pay as You

Throw - PAYT) which has been effective in reducing the size of the municipal waste stream. Source

reduction is typically measure by efficiencies and cutbacks in waste. Toxics use reduction is a more

controversial approach to source reduction that targets and measures reductions in the upstream use

of toxic materials.

Toxics use reduction emphasizes the more preventive aspects of source reduction but due to its

emphasis on toxic chemical inputs, has been oppose more vigorously by chemical manufacturers.

Resource recovery

A relatively recent idea in waste management has been to treat the waste material as a resource to be

exploited, instead of simply a challenge to be managed and disposed of. There are a number of

different methods by which resources may be extracted from waste: the materials may be extracted

and recycled, or the calorific content of the waste may be converted to electricity.

The process of extracting resources or value from waste is variously referred to as secondary

resource recovery, recycling, and other terms. The practice of treating waste materials as a resource

is becoming more common, especially in metropolitan areas where space for new landfills is

becoming scarcer.

There is also a growing acknowledgement that simply disposing of waste materials is unsustainable

in the long term, as there is a finite supply of most raw materials. There are a number of methods of

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recovering resources from waste materials, with new technologies and methods being developed

continuously.

In some developing nations some resource recovery already takes place by way of manual laborers

who sift through un-segregated waste to salvage material that can be sold in the recycling market.

These unrecognized workers called waste pickers or rag pickers, are part of the informal sector,

but play a significant role in reducing the load on the Municipalities' Solid Waste Management

departments.

There is an increasing trend in recognizing their contribution to the environment and there are efforts

to try and integrate them into the formal waste management systems, which is proven to be both cost

effective and also appears to help in urban poverty alleviation. However, the very high human cost

of these activities including disease, injury and reduced life expectancy through contact with toxic or

infectious materials would not be tolerate in a developed country.

Recycling

Recycling means to recover of other use a material that would otherwise be consider waste.

The popular meaning of ‘recycling’ in most developed countries has come to refer to the widespread

collection and reuse of various everyday waste materials. They are collected and sorted into common

groups, so that the raw materials from these items can be used again (recycled).

In developed countries, the most common consumer items recycled include aluminum beverage

cans, steel, food and aerosol cans, HDPE and PET plastic bottles, glass bottles and jars, paperboard

cartons, newspapers, magazines, and cardboard. Other types of plastic (PVC, LDPE, PP, and PS) are

also recyclable, although not as A materials recovery facility, where different materials are separated

for recycling commonly collected. These items are usually composed of a single type of material,

making them relatively easy to recycle into new products.

The recycling of obsolete computers and electronic equipment is important, but more costly due to

the separation and extraction problems.

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Electronic waste is send to Asia, where recovery of the gold and copper can cause environmental

problems Recycled or used materials have to compete in the marketplace with new (virgin)

materials.

The cost of collecting and sorting the materials often means that they are equally or more expensive

than virgin materials. This is most often the case in developed countries where industries producing

the raw materials are well established. Practices such as trash picking can reduce this value further,

as choice items are removing (such as aluminum cans).

In some countries, recycling programs are subsidized by deposits paid on beverage containers. The

economics of recycling junked automobiles also depends on the scrap metal market except where

recycling is mandated by legislation (as in Germany). However, most economic systems do not

account for the benefits to the environment of recycling these materials, compared with extracting

virgin materials. It usually requires significantly less energy, water and other resources to recycle

materials than to produce new materials. For example, recycling 1000 kg of aluminum cans saves

approximately 5000 kg of bauxite ore being mined (source: ALCOA Australia) and prevents the

generation of 15.17 tones CO2eq greenhouse gases; recycling steel saves about 95% of the energy

used to refine virgin ore (source: U.S. Bureau of Mines).

In many areas, material for recycling is collect separately from general waste, with dedicated bins

and collection vehicles. Other waste management processes recover these materials from general

waste streams. This usually results in greater levels of recovery than separate collections of

consumer-separated beverage containers, but are more complex and expensive.

Waste management techniques

Managing municipal waste, industrial waste and commercial waste has traditionally consisted of

collection, followed by disposal. Depending upon the type of waste and the area, a level of

processing may follow collection. This processing may be to reduce the hazard of the waste, recover

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material for recycling, produce energy from the waste, or reduce it in volume for more efficient

disposal.

Landfill:

Disposing of waste in a landfill is the most traditional method of waste disposal, and it remains a

common practice in most countries. Historically, landfills were often established in disused quarries,

mining voids or borrow pits.

A properly-designed and well-managed landfill can be a hygienic and relatively inexpensive method

of disposing of waste materials in a way that minimizes their impact on the local environment.

Older, poorly-designed or poorly-managed landfills can create a number of adverse environmental

impacts such as

Wind-blown litter,

Attraction of vermin, and

Generation of leach ate which can pollute groundwater and surface water.

Another byproduct of landfills is landfill gas (mostly composed of methane and carbon dioxide),

which is produced as organic waste breaks down an aerobically. This gas can create odor problems,

kill surface vegetation, and is a greenhouse gas.

Design characteristics of a modern landfill are:-

Include methods to contain leach ate, such as clay or plastic lining material.

Disposed waste is normally compacted to increase its density and stabiles the new landform,

covered to prevent attracting vermin (such as mice or rats) and reduce the amount of wind-

blown litter. landfills also landfill compaction vehicles in operation have a landfill gas

extraction system installed after closure to extract the landfill gas generated by the

decomposing waste materials.

Gas is pumped out of the landfill using perforated pipes and flared off or burnt in a gas

engine to generate electricity.

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Even flaring the gas is a better environmental outcome than allowing it to escape to the

atmosphere, as this consumes the methane, which is a far more potent greenhouse gas than

carbon dioxide.

Many local authorities, especially in urban areas, have found it difficult to establish new landfills

due to opposition from owners of adjacent land. Few people want a landfill in their local

neighborhood. As a result, solid waste disposal in these areas has become more expensive as

material must be transported further away for disposal.

This fact, as well as growing concern about the impacts of excessive materials consumption, has

given rise to efforts to minimize the amount of waste sent to landfill in many areas. These efforts

include taxing or levying waste sent to landfill, recycling the materials, converting material to

energy, designing products that use less material, and legislation mandating that manufacturers

become responsible for disposal costs of products or packaging. A related subject is that of industrial

ecology, where the material flows between industries is studied. The by-products of one industry

may be a useful commodity to another, leading to a reduced materials waste stream.

Some futurists have speculated that landfills may one day be mined: as some resources become

scarcer, they will become valuable enough that it would be economical to 'mine' them from landfills

where these materials were previously discarded as valueless. A related idea is the establishment of a

'mono-fill' landfill containing only one waste type (e.g. waste vehicle tyres), as a method of long-

term storage.

Incineration:

Incineration is a waste disposal method that involves the combustion of waste at high temperatures.

Incineration and other high temperature waste treatment systems are described as "thermal

treatment". In effect, incineration of waste materials converts the waste into heat, gaseous emissions,

and residual solid ash.

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Other types of thermal treatment include pyrolysis and gasification. A waste-to-energy plant (WtE)

is a modern term for an incinerator that burns wastes in high-efficiency furnace/boilers to produce

steam and/or electricity and incorporates modern air pollution control systems and continuous

emissions monitors.

This type of incinerator is sometimes called an energy-from-waste (EfW) facility. Incineration is

popular in countries as Japan where land is a scarce resource, as they do not consume as such area as

a landfill.

Sweden has been a leader in using the energy generated from incineration over the past 20 years.

Denmark also extensively uses waste-to-energy incineration in localised combined heat and power

facilities supporting district-heating schemes.

Incineration is carried out both on a small scale by individuals, and on a large scale by industry. It is

recognised as a practical method of disposing of certain hazardous waste materials (such as

biological medical waste), though it remains a controversial method of waste disposal in many

places due to issues such as emission of gaseous pollutants.

Composting and anaerobic digestion :

Active compost heap Waste materials that are organic in nature, such as plant material, food scraps,

and paper products, are increasingly being recycled. These materials are put through a composting

and/or digestion system to control the biological process to decompose the organic matter and kill

pathogens.

The resulting stabilized organic material is then recycled as mulch or compost for agricultural or

landscaping purposes. There are a large variety of composting and digestion methods and

technologies, varying in complexity from simple windrow composting of shredded plant material, to

automated enclosed-vessel digestion of mixed domestic waste. These methods of biological

decomposition are differentiated as being aerobic in composting methods or anaerobic in digestion

methods, although hybrids of the two methods also exist.

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Mechanical biological treatment;

Mechanical biological treatment (MBT) is a technology category for combinations of mechanical

sorting and biological treatment of the organic fraction of municipal waste.

MBT is also sometimes termed BMT- Biological Mechanical Treatment however; this simply refers

to the order of processing.

The "mechanical" element is usually a bulk handling mechanical sorting stage. This either removes

recyclable elements from a mixed waste stream (such as metals, plastics and glass) or processes it in

a given way to produce a high calorific fuel given the term refuse derived fuel (RDF) that can be

used in cement kilns or power plants. Systems, which are configure to produce RDF, include

Herhofand Ecodeco. It is a common misconception that all MBT processes produce RDF. This is not

the case. Some systems such as Arrow Bio simply recover the recyclable elements of the waste in a

form that can be sending for recycling. Arrow Bio UASB anaerobic digesters, Hiriya, Tel Aviv,

Israel The "biological" element refers to either anaerobic digestion or composting.

Anaerobic digestion breaks down the biodegradable component of the waste to produce biogas and

soil conditioner. The biogas can be use to generate renewable energy. More advanced processes such

as the Arrow-Bio Process enable high rates of gas and green energy production without the

production of RDF. This is facilitate by processing the waste in water. Biological can also refer to a

composting stage.

Here the organic component is treat with aerobic microorganisms. They break down the waste into

carbon dioxide and compost. There is no green energy produced by systems simply employing

composting. MBT is gaining increased recognition in countries with changing waste management

markets where WSN Environmental Solutions has taken a leading role in developing MBT plants.

Pyrolysis & gasification:

Pyrolysis and gasification are two related forms of thermal treatment where waste materials are

heated to high temperatures with limited oxygen availability.

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The process typically occurs in a sealed vessel under high pressure. Converting material to energy

this way is more efficient than direct incineration, with more energy able to be recovered and used.

Pyrolysis of solid waste converts the material into solid, liquid and gas products. The liquid oil and

gas can be burn to produce energy or refined into other products.

The solid residue (char) can be further refined into products such as activated carbon.

Gasification is use to convert organic materials directly into a synthetic gas (syn-gas) composed of

carbon monoxide and hydrogen. The gas is then burn to produce electricity and steam. Gasification

is use in biomass power stations to produce renewable energy and heat.

12. Recycling of e-waste

The conventional e-waste processing and recycling is basically a five-step process

1. Generation and Stockpiling

Many different “economic actors” purchase, use, and then stockpile or discard electronic waste.

These range from manufacturers such as MNCs to large and small businesses, households,

institutions, and non-profit organizations.

2. Collection

There are wide varieties of possible collection alternatives for this e-waste. Varieties of entities are

providing these services including the electronics industry, private or nonprofit recycling services,

and the public sector through the solid waste management and recycling infrastructure.

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3. Handling & Brokering

The next link in the cycle is the handling and brokering services. Here computers, TVs, monitors and

other collected electronics are consolidated and made ready for processing and/or sorted to

determine what equipment can be refurbished or reused as whole units and what equipment must be

disassembled for commodity processing.

4. Processing

After electronic equipment is dismantling, it is then process into either feedstock for new production

or refurbished into new equipment. Outputs from de-manufacturing activities include scrap

commodities such as glass, plastics, and metals the primary elements from which all electronic

hardware is made. For export, and to a lesser extent national processing markets, there are significant

issues associated with the environmental and health practices of current service providers in this part

of the cycle.

5. Production

The final step in this cycle is to turn the processed commodities or refurbished whole electronics

back into new products for sale and consumption by end users. There are many different players and

industries involved in this production process. The recycling fraction is miniscule compared with the

production of product using virgin materials. The substances procured by recycling may be use for

several purposes, even for manufacturing the very same equipments they were derived from.

Recycling/Recovery System

First of the operations involves dismantling and rapid separation of primary materials. The following

materials are separate for further recycling:

· Material containing copper: Including printer and other motors, wires and cables, CRT yokes,

circuit boards, etc

· Steel: Including internal computer frames, power supply housings, printer parts, washing

machines, refrigerator, etc.

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· Plastic: Including housings of computers, printers, faxes, phones, monitors, keyboards, etc.

· Copper: Extracted from transformer and CRT after their dismantling

· Circuit Boards: These come from many applications including computers, phones, disc drives,

printers, monitors, etc. Each of these processes has been described below. Following describes the

conventional way of recycling a personal computer.

Bifurcation of electronic scrap

11.2.1. Printed Circuit Boards (PCBs)

The printed circuit boards contain heavy metals such as antimony, gold, silver, chromium, zinc, lead,

tin and Copper. According to some estimates, there is hardly any other product for which the sum of

the environmental impacts for raw material, industrial refining and production, use and disposal is as

extensive as for printed circuit boards. The methods of salvaging material from circuit boards are

highly destructive and harmful as they involve heating and open burning for the extraction of metals.

Even after such harmful methods are used, only a few of the materials are recovered. The recycling

of circuit boards, drawn from monitors, CPU, disc and floppy drives, printers, etc. involves a number

of steps.

Characteristics of PCB Scrap

PCB scrap is characterise by significant heterogeneity and relatively high complexity, although with

the levels of complexity being somewhat greater for populated scrap boards. As has been seen in

respect of materials composition, the levels of inorganic in particular are diverse with relatively low

levels of precious metals being present as deposited coatings of various thicknesses in conjunction

with copper, solders, and various alloy compositions, non ferrous and ferrous metals. In spite of the

inherent heterogeneity and complexity, there are too many differences in the intrinsic physical and

chemical properties of the many materials and components present in scrap PCBs, and indeed

electronic scrap as a whole, to permit recycling approaches that separate such into their individual

fractions.

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The following characteristics ultimately govern mechanical and hydrometallurgical separation and it

is based upon such that current and potential recycling techniques and infrastructures have been

envisaged, developed and implemented:-

Density Differences

Differences in density of the materials contained within scrap PCBs have formed the basis for

separation methods subsequent to their liberation as free constituents. The specific gravity ranges of

typical materials are as shown below:-

Table-3

Materials Specific Gravity Range (g/cm3)

Gold, platinum group, tungsten 19.3 - 21.4

Lead, silver, molybdenum 10.2 - 11.3

Magnesium, aluminium, titanium 1.7 - 4.5

Copper, nickel, iron, zinc 7.0 - 9.0

GRP 1.8 - 2.0

With these densities not being significantly affected by the addition of alloying agents or other

additives, it is predictable that the deployment of various density separation systems available within

the raw materials process industry may be utilized to effect separation of liberated constituents of a

similar size range.

The utilization of density differences for the recovery of metals from PCB scrap has been

investigated on many occasions and air classifiers have been used extensively to separate the non

metallic (GRP) constituents, whilst sink-float and table separation techniques have been utilised to

generate non ferrous metal fractions.

Air techniques that effectively combine the actions of a fluidised bed, a shaking table and an air

classifier, have been successfully implemented in applications involving a diversity of electronic

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scrap separations. It is essential, as has been noted, that the feed material must be of a narrow size

range to guarantee effective stratification and separation.

Magnetic and Electrical Conductivity Differences

Ferrous materials may be readily separate with the application of low intensity magnetic separators

that have been well developing in the minerals processing industry.

Many non-ferrous materials in respect of their high electrical conductivity may be separated by

means of electrostatic and eddy current separators. Eddy current separation has been developing

within the recycling industry since strong permanent magnets, such as iron boron- neodymium, have

become available.

Rotating belt type eddy current separation is the most extensively used approach for the recovery of

nonferrous metal fractions. In application, the alternating magnetic fields caused by the rapidly

rotating wheel mounted with alternating pole permanent magnets result in the generation of eddy

currents in non-ferrous metal conductors, which in turn, generate a magnetic field that repels the

original magnetic field.

The resultant force, arising from the repulsive force and the gravitational force permits their

separation from non-conducting materials.

Polyformity

One of the important aspects of both PCB and electronic scrap is the polyformity of the various

materials and components and the effect this can have on materials liberation. It is essential that any

shredding and separation processes take this into account. In eddy current separation, the shape of

conducting components, in addition to their particle sizes and conductivity/density ratios, has a

significant effect on the generated repulsive forces that ultimately govern the separation efficiency.

For instance, multiple induced current loops may be establishing in conductors with irregular shapes

with the induced magnetic fields counteracting each other and reducing the net repulsive force.

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Liberation Size

The degree of liberation of materials upon shredding (to cut or tear into small pieces) and

comminuting (to pulverize) is crucial (trying) to the efficiency and effectiveness of any subsequent

separation process in respect of yield, quality of recovered material and energy consumption of the

process.

This is especially critical in mechanical separation approaches. The comminuting of scrap PCBs has

been shows to generate a high level of material liberation and levels as high as 96% to 99% have

been report for metallic liberation after comminuting to sub 5mm particulates. It must noted,

however, that a continual observation from recyclers is that liberation levels such as these are

atypical (not typical) of actual yields and that a fundamental constraint on mechanical processing is

the loss, particularly of precious metal content, that appears to be inherent due primarily to the nature

of many plastic-metal interfaces.

Chemical Reactivity

Hydrometallurgical approaches depend on selective and non-selective dissolution to achieve a

complete solublesation of all the contained metallic fractions within scrap PCBs. Although all

hydrometallurgical approaches clearly benefit from prior comminution this is primarily undertaken

to reduce bulk volume and to expose a greater surface area of contained metals to the etching

(corrosive action of an acid instead of by a burin) chemistry.

Selective dissolution approaches may utilise high capacity etching chemistries based on cupric

chloride or ammonium sulphate for copper removal, nitric acid based chemistries for solder

dissolution and aqua regia for precious metals dissolution, where as non selective dissolution may be

carried out with either aqua regia or chlorine based chemistry.

Electropositivity

Dissolved metals generated via chemical dissolution are present as ionised species within an aqueous

media and may be recovered via high efficiency electrolytic recovery systems.

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In the instance of selective dissolution, a single metal is recovered as pure electrolytic grade

material, usually in sheet form; from the spent etching solution with certain etching chemistries

permitting regeneration of the liquors for reuse as etch chemistries. In the instance of selective

dissolution, use may be made of the differing electro-positivity of the contained ionised metallic

species to selective recovery metals at discrete levels of applied voltage.

Disassembly

Disassembly in practice

In the practice of recycling of waste electric and electronic equipment, selective disassembly

(dismantling) is an indispensable process since:

(1) The reuse of components has first priority,

(2) Dismantling the hazardous components is essential,

(3) It is also common to dismantle highly valuable components and high-grade materials such as

printed circuit boards, cables, and engineering plastics in order to simplify the subsequent recovery

of materials.

Most of the recycle plants utilize manual dismantling. The main obstacles preventing automated

disassembly from becoming a commercially successful activity are:

(1) Too many different types of products,

(2) the amount of products of the same type is small,

(3) General disassembly-unfriendly product design,

(4) General problems in return logistics and

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(5) Variations in returned amounts of products to be disassembled. Fortunately, research in

the field of product design for disassembly has gained momentum in the past decade.

One good idea is self-disassembly, which is called active disassembly using smart materials

(ADSM). Chiodo reported the application of shape memory polymer (SMP) technology to the active

disassembly of modern mobile phones. The smart material SMP of polyurethane (PU) composition

was employed in the experiments. This method provides a potential dismantling scenario for the

removal of all components if this material was to be developed for surface mount components.

Research into using ADSM in other small electronics also has been done to handle units such as

telephones, cell phones, PCB/component assemblies, cameras, battery chargers, photocopier

cartridges, CRTs, computer casings, mice, keyboards, game machines nd stereo equipment.

Mechanical/physical recycling process

1. Screening:

Screening has not been only utilized to prepare a uniformly sized feed to certain mechanical process,

but also to upgrade metals contents. Screening is necessary because the particle size and shape

properties of metals are different from that of plastics and ceramics.

The primary method of screening in metals recovery uses the rotating screen, or trammel, a unit,

which is widely used in both automobile scrap and municipal solid waste processing. This unit has a

high resistance to blinding, which is important with the diverse array of particle shapes and sizes

encountered in waste. Vibratory screening is also commonly used, in particular at non-ferrous

recovery sites, but wire blinding is a marked problem.

2. Shape separation:

Shape separation techniques have been mainly developed to control properties of particles in the

powder industry. The separation methods were classified into four groups by Furuuchi. The

principles underlying this process makes use of the difference:

(1) The particle velocity on a tilted solid wall,

(2) The time the particles take to pass through a mesh aperture,

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(3) The particle’s cohesive force to a solid wall, and

(4) The particles settling velocity in a liquid.

Shape separation by tilted plate and sieves is the most basic method that has been used in recycling

industry. An inclined conveyor and inclined vibrating plate were used as a particle shape separator to

recover copper from electric cable waste printed circuit board scrap and waste television and

personal computers.

3. Magnetic separation:

Magnetic separators, in particular, low-intensity drum separators are widely used for the recovery of

ferromagnetic metals from non-ferrous metals and other non-magnetic wastes. Over the past decade,

there have been many advances in the design and operation of high-intensity magnetic separators,

mainly because of the introduction of rare earth alloy permanent magnets capable of providing very

high field strengths and gradients.

In Table 6, we can see that the use of high-intensity separators makes it possible to separate copper

alloys from the waste matrix. An intense field magnetic separation is achievable at least for the

following three alloy groups

• Copper alloys with relatively high mass susceptibility (Al multi-compound bronze);

• Copper alloys with medium mass susceptibility (Mn multi-compound bronze, special

brass);

• Copper alloys with low mass susceptibility and/or diamagnetic material behavior(Sn and Sn

multi-compound bronze, Pb and Pb multi-compound bronze, brass with low Fe content).

4 Electric conductivity-based separation:

Electric conductivity-based separation separates materials of different electric conductivity (or

resistivity) (Tables 5). There are three typical electric conductivity-based separation techniques:

(1) Eddy current separation,

(2) Corona electrostatic separation, and

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(3) Triboelectric (electricity generated by friction) separation.

In the past decade, one of the most significant developments in the recycling industry was the

introduction of Eddy current separators whose operability is base on the use of rare earth permanent

magnets. The separator were initially developed to recover non-ferrous metals from shredded

automobile scrap or for treatment of municipal solid waste, but is now widely used for other

purposes including foundry casting sand, polyester polyethylene terephthalate (PET), electronic

scrap, glass cullet, shredder fluff, and spent pot liner.

Currently, Eddy current separators are almost exclusively used for waste reclamation where they are

particularly suited to handling the relatively coarse sized feeds. The rotor-type electrostatic

separator, using corona charging, is utilised to separate raw materials into conductive and non-

conductive fractions. The extreme difference in the electric conductivity or specific electric

resistance between metals and non-metals supplies an excellent condition for the successful

implementation of a corona electrostatic separation in recycling of waste.

To date, electrostatic separation has been mainly utilized for the recovery of copper or aluminum

from chopped electric wires and cables, more specifically the recovery of copper and precious

metals from printed circuit board scrap Triboelectric separation makes it is possible to sort plastics

depending on the difference in their electric properties (Table 4). For the processing of plastics

waste, research has shown many obvious advantages of triboelectric electrostatic separation, such as

independence of particle shape, low energy consumption, and high throughput

TABLE-4 Mechanical separation processes based on electric characteristics of Materials

Processes Separatio

n

criteria

Principles of separation Sorting task Workable

particle

size

ranges

Eddy current

separation

Electric

conductivi

Repulsive forces exerted in

the electrically conductive

Non-ferrous

metal/nonm

>5mm

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ty

and

density

particles due to the

interaction between the

alternative magnetic field

and the Eddy currents

induces by the magnetic field

(Lorentz force)

etal

separation

Corona

electrostatic

separation

Electric

conductivi

ty

Corona charge and

differentiated discharge lead

to different charges of

particles and this to action of

different forces (particularly,

image forces)

Metal/

nonmetal

separation

0.1–5mm

(10mm

for

laminar

particles)

Triboelectric

separation

Dielectric

constant

Tribo-charge with different

charges (+ or −) of the

components cause different

force directions

Separation

of Plastics

(nonconduc

tors)

<5 (10)

mm

5 Density-based separations:

Several different methods are employed to separate heavier materials from lighter ones. The

difference in density of the components is the basis of separation. Table 4 shows that density-based

separation processes have found widespread application in non-metal/metal separation.

Gravity concentration separates materials of different specific gravity by their relative movement in

response to the force of gravity and one or more other forces, the latter often being the resistance to

motion offered by a fluid, such as water or air. The motion of a particle in a fluid is dependent not

only on the particle’s density, but also on its size and shape, large particles being affected more than

smaller ones. In practice, close size control of feeds to gravity processes is required in order to

reduce the size effect and make the relative motion of the particle specific gravity dependent.

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TABLE-5 Density separation processes utilized for non-metal/metal separation

Utilized for following sorting tasks

Density

separation

Process

Workable

piece

Sizes

(mm)

Plastics

waste

Aluminum

scrap

Lead

battery

scrap

Cable

scrap

Electronic

scrap

Light

steel

scrap

Sink-float separation

In liquids * * * *

In heavy media

Gravity separator 5–150 * * * *

Hydro cyclone + <50 *

In aero suspensions

In aero chutes 0.7–3 *

In fluidized bed

Trough separators

0.7–5

Sorting by jigging

Hydraulic jigs 2–20 *

Pneumatic jigs <3 *

Sorting in chutes and on tables

Aero-chutes 0.6–2 *

Aero-tables <4 *

Up-stream separation

Up-stream

hydraulic

Separation

5–150 * * *

Up-stream

pneumatic

Separation

<300 *

Mechanical Approaches of recycling electronic scrap

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As may be anticipated, all of the work undertaken on mechanical systems has been with the primary

objective of enhancing separation yield of the various fractions, particularly the precious metal

bearing ones.

The basic mechanical techniques deployed in the treatment of scrap PCBs and electronic assemblies

have been adapted or adopted from the raw materials processing sector and refinement has sought to

address both yield constraints and ultimately cost effectiveness either of the approaches, used singly

or in an integrated manner.

The problems associated with yield were apparent from early attempts to produce a model

methodology for handling all types of electronic scrap as instanced by the US Bureau of Mines

(USBM) approach in the late 1970s and early 1980s. The separation route, developed up to a 250 kg

per hour pilot plant, comprised shredding, air separation, and magnetic, eddy current and

electrostatic separation to generate aluminum rich, copper rich (including major precious metal

fraction), light air classified and ferrous fractions.

The yield, however, was such that no commercial uptake of this approach has been instanced. The

relatively poor yields or levels of separation obtained from this approach, were undoubtedly a result

of the use of a standard hammer mill having no provision, or levels of refinement, to cope with clear

comminution (pulverize) of aluminium, the use of a ramp type eddy currentseparator of low capacity

and selectivity and the use of a high tension separator for metals/non metals, which has been since

demonstrated as having low capacity and high susceptibility to humidity.

There was little further meaningful development work on the implementation of mechanical

treatment approaches until the early 1990s when Scandinavian Recycling AB in Sweden

implemented their mechanical concept for electronic scrap handling which did not specifically

address the treatment of scrap PCBs but rather removed PCBs for specialist treatment as part of the

pre sorting stage. Subsequent to this development, work in both Germany and Switzerland has seen

the implementation of mechanically based approaches for the handling and separation of electronic

scrap with the work at FUBA dedicated to scrap PCBs being a notable example of this activity.

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In 1996, Noell Abfall and Energietechnik GmbH in Germany implemented a 21,000 tonnes per

annum plant with the capability of handling a wide variety of electronics scrap but specifically

intended for redundant telecommunications scrap. The system again involves PCB scrap and the

inherent precious metal content being subject to prior manual disassembly. The overall methodology

deploys a three stage liberation and sequential separation route with ferromagnetic removal via

overhead permanent magnets and eddy current techniques because of their ability to optimise the

handling of fractions in the 5 to 200 mm particle size range.

Air table techniques were utilised for the separation of particulate fractions in the 5 to 10 mm, 2 to 5

mm and less than 2 mm ranges respectively. Mechanical and physic mechanical approaches to the

treatment of scrap PCBs may be deployed as standalone treatment stages, (i.e. pulverisation,

magnetic separation, or integrated into a complete treatment system with the output being metallic

and non-metallic fractions). The metallic output would be destined for hydrometallurgical

refinement via smelting where as the nonmetallic output would find applications in the secondary

plastics marketplace or be utilised within dedicated developed applications.

As reported, FUBA has developed its total mechanical treatment system, albeit only currently

utilised for nonpopulated board scrap or ancillary laminate waste through this latter route. There are

commercially available turnkey mechanical systems for the treatment of

a wide range of electronic scrap materials including populated and non-populated PCBs. One such is

that developed by hamos GmbH in Germany, which is an automated integrated mechanical system,

comprising the following stages:

• Primary coarse size reduction, accomplished with a shredder having multi-use rotational

knives;

• Coarse ferrous metal separation, accomplished with rare earth magnets sited above an

oscillating conveyor belt feed to allow high efficiency ferrous separation across a range of

particle sizes;

• Pulverisation in which circuit board assemblies are pulverised within a hammer mill

utilising high abrasion resistance hammers and liners and proprietary grates with the action

of the mill inducing a 'spherising' effect on the metallic articulates;

• Classification, utilising self-cleaning sieves;

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• Electrostatic separation, allowing virtually complete separation of metallic fractions with

recirculation of mid-range particulate fractions

• Further size reduction, cosisting of secondary pulverisation to effect size reduction on

oversized particulates.

The hamos system can additionally incorporate density separation for aluminium extraction and dust

generation treatment of any such outfall from the hammer mills via secondary electrostatic

separators. The complete conveyor based systems are operated at negative pressures to eliminate any

airborne pollution and are currently available with treatment capabilities up to 4 tonnes per hour of

input feed.

All products from the system viz mixed plastic, metallic and extracted ferrous and aluminium is

bagged automatically for onward shipment. Considerable work has been undertaken on enhancing

the effectiveness of mechanical treatment systems. For example, the development of newer

pulverizing process technology via the application of multiple pulverising rotors and ceramiccoated

systems has enabled the generation of sub-millimetre particulate comminution. This in turn has

enabled the efficiency of subsequent centrifugal separation techniques to realize 97% copper

recovery yields.

The effectiveness of the pulverising process has been improved by the adoption of dual pulverising

stages: a crushing process and a fine pulverising process. The crushing process combines cutting and

shearing forces and the fine pulverising process combines shearing and impact forces. With such

effective particulate comminution both screen separation and gravity separation have been

investigated and conclusions drawn that the most effective approach was by gravity using a

centrifugal classifier with a high air vortex system.

Researchers at Daimler-Benz in Ulm, Germany, have developed a mechanical treatment approach

that has the capability to increase metal separation efficiencies, even from fine dust residues

generated after particulate comminution in the treatment of scrap PCB assemblies. They considered

a purely mechanical approach to be the most cost effective methodology and a major objective of

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their work was to increase the degree of purity of the recovered metals such that minimal pollutant

emissions would be encountered during subsequent smelting.

Their process comprises the initial coarse size reduction to ~2 cm x 2 cm dimensioned fractions

followed by magnetic separation for ferrous elements. A low temperature grinding stage then

follows this. The embrittlement of polymeric components at temperatures less than 70°C was found

to enable enhanced separation from non-ferrous metallic components when subjected to grinding

within a hammer mill. In operation the hammer mill was fed with liquid nitrogen at minus 196°C,

which served to both impart brittleness to the plastic feedstock constituent and to effect process

cooling. Additionally, the grinding of material within such an inert atmosphere eliminated any 17

likelihood of oxidative by product formation from the plastics, such as dioxins and furans.

Subsequent to this enhanced grinding stage the metallic and non metallic fractions were separated

via sieving (an instrument with a meshed or perforated bottom, used for separating course from fine

parts of loose matter, for straining liquids) and electrostatic stages. Cost analyses undertaken by

Daimler-Benz engineers have indicated that such a process may be economically viable even when

dealing with relatively low-grade PCB scrap having little precious metal content.

Ongoing activities are concerned with development of the treatment of separated polymeric fractions

in conjunction with Mitsubishi Heavy Industries that have set up a gasification and methanol (a

colorless, volatile, water-soluble, poisonous liquid, CH4O, obtained by the destructive distillation of

wood or the incomplete oxidation of natural gas, or produced synthetically from carbon monoxide

and hydrogen, used chiefly as a solvent, a fuel, and an automobile antifreeze and in the synthesis of

formaldehyde) sis plant to such effect. Air table separation systems have been researched with a

view to effecting separation of metallic and plastic components from an input feed of screened 7 mm

shredded particulate scrap PCBs post ferromagnetic separation. Recovery rates for copper, gold and

silver of 76%, 83% and 91% respectively were considered to validate the approach, but only for low-

grade PCB scrap or general electronic scrap.

Hydrometallurgical Approaches

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A number of hydrometallurgical (the technique or process of extracting metals at ordinary

temperatures by leaching ore with liquid solvents)approaches have been developed through to pilot

plant stage with preliminary cost studies indicating the potential recovery of all materials, with the

exception of discrete components, at an operational profit. In the USA, a methodology based on

solvolysis has been developed to enable both the more efficient recovery of metals and the recovery

of plastic materials such as epoxides at high quality and with the additional benefit of having the

capability to extract both halogens and brominated hydrocarbon derivatives. On a relatively small

scale there have been a number of hydrometallurgical approaches traditionally pursued in the

recovery specifically of gold from pins and edge connectors.

Such methodologies have usually been deployed on discrete edge connectors and gold-coated

assemblies that have been manually separated from the scrap board via the use of air knives etc. The

approaches have either liberated gold as metal flake via acidic dissolution of the copper substrates or

dissolution of the gold in cyanide or thiourea based lea chants followed by electro winning or

chemical displacement or precipitation with powdered zinc.

The use of non-selective leachants to dissolve the non precious metal content of scrap PCBs has also

received attention. Various studies have been undertaken into the viability of utilising dilute mineral

acids in conjunction with subsequent metal recovery techniques based on concentration and

separation such as solvent extraction, ion exchange, adsorption and cementation.

In the UK, there have been two potentially significant development projects undertaken on

hydrometallurgical approaches to the recycling of scrap PCBs with both having demonstrated

viability to a pre pilot plant stage.

The first of these approaches is from a Cambridge University led consortium, which deploys a

selective dissolution electrolytic recovery route for discrete metal constituents. The solder recovery

stage employs a solder selective (non copper etching) regenerable leachant based on fluoroboric

acid. This may or may not be deployed prior to mechanical pre treatment, from which the dissolved

solder can be electrolytically recovered in pure metallic form. Subsequent selective leaching of

copper and PMG metals is then carried out. The ability to remove selectively solder prior to

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mechanical comminution has specific advantages in enabling disassembly and component integrity

and recovery. Mechanical pre treatment methodologies followed by the Cambridge group have

included shredding, magnetic separation, eddy current separation and classification.

The second development is that of the Imperial College, London (ICL) consortium which has taken

shredded and classified sub 4mm PCB populated PCB scrap through a single leachate route

comprising electro-generated chlorine in an acidic aqueous solution of high chloride ion activity.

This has produced a multi metal leach electrolyte containing all of the available metal content at

generally mass transport controlled rates with respect to dissolved chlorine. The viability of

subsequent metal recovery via electrolytic membrane cells with discrete metal separation has also

been demonstrated. To summarize the above discussions:

• Hydrometallurgical approaches offer a viable methodology in maximising the recovery of

intrinsic metal value, particularly precious metals, and should be further developed through

pilot plant stages to commercialisation.

• No single treatment approach will be appropriate for the handling of all scrap PCBs because

of their diversity and varying intrinsic worth. Rather, an integrated hierarchy of approaches

that encompasses disassembly and mechanical and hydrometallurgical methodologies will be

needed to generate either materials or components for direct reuse or downstream application

or a non-toxic feedstock for pyrolytic refining.

PWB Waste

Crushing process

Pulverising process

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Fine pulverising

Gravity Separation

Copper Rich Powder Glass Fiber & Resin

Recycling of copper filler in construction materials

Fig-5 97% recovery of Copper from PWBs

Extraction of IC/ other components from PCB

IC/other components from PCBs are manually extracted as shown in figure This process is common

for PC, TV and cell-phone. The E-waste stream from cell-phone joins the E-waste stream of PC and

TV.

Fig-6 Extraction of IC/ other components from PCB

Recovery of Gold

Gold recovery techniques and hazards

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Three processes to recover gold from e-waste are described. The main materials used are determined

and partly quantified. From this information, the major hazard-“hot spots” to health and environment

are identified.

Methodology

The system is described using the material flow analysis (MFA). “Material flow analysis (MFA) is

a systematic assessment of the flows and stocks of materials within a system defined in space and

time.” (Brunner and Rechenberger, 2004). The goal of an MFA is to determine the in- and outputs of

a process and to understand the flows within a system. The analysis of material fluxes is an essential

approach to gain a system comprehension and an understanding of the processes occurring within

the anthrop sphere (Binder et al., 2001). “Because of the law of the conservation of matter, the

results of an MFA can be controlled by a simple material balance comparing all inputs, stocks, and

outputs of a process. It is this distinct characteristic of MFA that makes the method attractive as a

decision-support tool in resource management, waste management, and environmental management”

(Brunner and Rechberger, 2004). In this analysis the used terminology has been developed according

to the terminology defined in the Practical Handbook of Material and Flow Analysis (Brunner and

Rechenberger, 2004).

Subsequent the mainly used terms in this thesis are defined:

A substance is any (chemical) element or compound composed of uniform units. All

substances are characterised by a unique and identical constitution and are thus homogenous.

The term material is use for a solid matter composed of heterogeneous units. A solution is

the product of mixed substances and materials and is a heterogeneous liquid.

A mixture is the product of mixed substances and is a homogeneous liquid.

Process is a term used for the transformation and transport of materials and substances.

A technique is defined to be a sequence of processes.

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A process step is an activity within a process (sub-process).

The system is defined by a group of processes, the interaction between these processes and

the system boundaries.

The conducted material flow analysis comprises four steps:

System description: The system is characterised determining the system border and the

single process steps referring to the processes of each technique. Using information from

literature and various experts the processes and process steps of the system are described.

Quantification: The in- and outputs of the system are measured and calculated/estimated

applying the principle of mass conservation.

Interpretation: The environmental hazard hot spots are detected with the beforehand

evaluations and are discussed.

Discussion: An overview of each evaluated system is given. In addition, some features

determined in the description and in the quantification of each process are discussed.

System DescriptionSystem definitionThe investigated system is part of the e-waste management system is illustrated in Figure. It consists

of the gold recovery technique of pre-processed (dismantled) printed wiring boards (PWBs).

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The system consists of a gold recovery technique divided in several processes that are required in

order to recover gold from the input material. The technique is divided into three processes:

Leaching, Separation and Purification. In the context of gold extraction, leaching is the dissolution

of a metal or mineral in a liquid (Marsden and House, 1992). During the separation, the gold is

extracted out of a solution or separated from a material. Purification is the procedure of rendering

something pure, i.e. cleaning it from impurities.

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The description of the techniques is based on different data sources: Observations, photographs,

documentation, literature research and interviews. techniques are used to recover gold is based on

gold mines from the ore as they are used to recover gold from pre-processed PWBs.

Currently about 20 informal facilities in and around Bangalore are involved in the recovery of

precious metals from e-waste (Rodriguez, 2005). All of them presumably use the same technique to

recover gold. Consultants of GTZ and EMPA are closely working together with an informal

association of recyclers called Eco BIRD. With the help of GTZ and EMPA, it was possible to use

these contacts and to work together with a gold recovery unit of Eco BIRD. The following paragraph

gives a short description of Eco BIRD and the investigated unit.

Eco BIRD

Fig-8 Eco BIRD (Rizwan’s) facility

In the informal sector in Bangalore, a recently founded association consisting of 11 recycling units

called Eco BIRD exists. The word “Eco” stands for “Eco-friendly” and BIRD is an acronym for

Bifurcation, Identification, Recycling and Disposal. The 11 recycling units either deal with scrap,

dismantle the equipment or recover precious metals. The examined facility belongs to Rizwan Khan

(president of Eco Bird) and is situated on a roof (approx. 46m2) in Gowripalya, Padarayanapura, a

suburb of Bangalore. There is a room (approx. 16 m2) on top of the roof, where the furnace is

situated and the materials and substances are stored in. The containers with acidic liquids are placed

outside. Rizwan employs three workers between the age 10 and 20. Several other people are also

using his facility. The material that is treated by Rizwan per year is estimated to be 1800 kg with a

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gold production of 7200g (Bineesha, 2006). To recover gold from e-waste two different techniques

are conducted according to the quality of the input material. If the gold concentration in the input

material is low (lowgrade material), “cyanide leaching” is used. If the input material is high-grade

material, they conduct “mercury amalgamation”.

Both of the processes are described in the following :-

Formal sector

In the formal sector, only one company, Surface Chem Finishers, is known conducting a gold

recovery process. It was possible to collaborate with this company and investigate the exercised

process. In the following paragraph a short description and scope of the company is given

Surface Chem Finishers

Fig-9 E-Parisaraa Pvt. Ltd.

“Surface Chem Finishers” is an ISO 9001 – 2000 certified gold plating unit in Peenya Industrial

Estate, Bangalore. It is a sister company of “E-Parisaraa Pvt. Ltd.” Which recycles and dismantles e-

waste. The vision of the director of the two companies is to be eco-friendly and low cost. “E-

Parisaraa” is located on the outskirt of Bangalore. About 5 % of the gold used for the gold plating in

“Surface Chem Finishers” is recovered from ewaste pre-processed at “E-Parisaraa”. Thus, gold

recovery is only a side task of Surface Chem Finishers.

Today there are 45 people working in the two companies. Three persons are involved in the gold

recovery process. At present, E Parisaraa is handling about one ton of e-waste per day. According to

Prakashchandra (Engineer of Surface Chem Finishers, E-Parisaraa Pvt. Ltd.), approximately 920 kg

of material is processed per year to recover gold. Thereof 440 g of gold is recovered per year.

Cyanide leaching at Eco BIRD

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Cyanide has been used in the mining industry for more than 100 years to recover gold. It is

universally used because of its relatively low cost and great effectiveness of gold dissolution.

The reaction takes place in an alkaline environment, which is important for economic and safety

reasons. It has been shown that the maximum dissolution of gold, silver, platinum and palladium in

cyanide solution is at pH 10-10.5. The observed cyanide leaching technique was conducted at around

pH 12.

This is almost ideal for the leaching process as the loss of cyanide is very low at pH 11.5 because the

loss due to hydrogen cyanide (HCN) formation is very low. The main chemical reaction consists of

four starting materials and substances: water, oxygen, gold and cyanide.

Cyanide is acting as the complexing agent in the process and oxygen as an oxidiser. However, other

elements contained in the electronic devices disturb this chemical reaction. For example, the present

copper will form cyanide complexes and cause an increased use of cyanide. These copper-cyanide

complexes will tend to inhibit the dissolution of gold.

Detailed description of the techniqueDuring a participating observation, this process had been investigated. The input material is provided

to the informal facility with this material, the process is conducted as it would be conducted with

purchased material and it is therefore an acceptable representative for the “usual” process. In the

following description the denominations (L1… P6) refer to the detailed and quantified flowchart in

Leaching

L 1: Lixiviation

The connectors are put into a plastic container and are doused with hot water. The gold leaching is

initiated by adding substance 1 (most probably potassium or sodium cyanide).Under mildly

oxidising conditions, the gold is dissolved. Adding cyanide results in a strong complex between

cyanide and gold. The reaction known as Elsner's Equation is:

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4 Au(s) + 8 CN-(aq) + O2(g) + 2 H2O(l) 4 Au(CN)2-(aq) + 4 OH-(aq)

Because cyanide is one of the strongest ligands several other complexes are formed (ex.: [Ag(CN)2]-,

[Cu(CN)2] -, [Ni(CN)4]-2).

Fig-10 Lixiviation with cyanide

L 2: Sieving / Washing

The components are removed from the pregnant (gold-bearing) solution and are washed with water.

This is important in order to deplete the waste components as good as possible of their gold. These

components are sometimes kept to recover copper in a separate process.

Fig-11 Sieving of components

The pregnant solution has a brownish colour.

Fig-12 Pregnant solution

Preparation of silver-salt

The silver-salt is prepared separately, conducting following process steps:

PS 1: Heating

A silver ingot, nitric acid and hot water are mixed together and heated for approx. 5 minutes to

dissolve the silver. The remaining silver biscuit is then taken out, the solution is poured into a plastic

bucket, and the tin container is washed with water.

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Ag + 2 HNO3 -> AgNO3+ NO2 + H2O

Fig-13 Silver nitrate

PS 2: Precipitation

Sodium chloride and water are added to the silver solution. The silver-salt precipitates as silver

chloride, which is a white precipitation. Sodium nitrate has a high solubility in water and is dissolved

in the solution.

AgNO3 + NaCl -> AgCl + NaNO3

PS 3: Decantation

The liquid part of the reaction mixture is poured into another container. Silver chloride remains on

the bottom of the bucket. Hot water is used to clean the remaining slag from the nitric acid by

decantation.

Fig-14 Silver chloride

PS 4: Mixing

Water, an unknown salt and caustic soda are mixed with the white precipitation. The reason for

adding caustic soda (NaOH) is to keep an alkaline environment. After a further decantation, the

silver-salt enters the main process.

Separation

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S 1: Gold formation

The separation is performed using the principles of the Merril-Crowe process3 (cementation with

zinc). Aluminium-foils and the silver-salt are added to the gold bearing solution. Aluminium

precipitates the gold and some silver because Al has the higher affinity to the cyanide ion than gold

and silver. The silver reacts with the free cyanide to prevent that the gold is dissolved again.

3 [Au(CN)2]- + 2 Al -> 2 Al3+ + 6 CN- + 3 Au(s)

4 Ag(s) + 8 CN-(aq) + O2(g) + 2 H2O(l) 4 Ag(CN)2-(aq) + 4 OH-(aq)

Fig -15 Adding aluminium

S 2: Decantation / Filtering

The grey sludge is separated from the solution by pouring the solution from one container to the

other and keeping the precipitation in the container. After doing so, the remaining slag is filtered

through a cloth.

Fig-16 Decantation

Fig-17 Filtering the mixture

3 The Merril-Crowe process is a separation technique for removing gold from cyanide solution,

usually using zinc.

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Purification

P 1: Melting

The cloth with its content is put into a crucible and is melted. During the melting process lime

(CaCO3) and two unknown substances are added. These substances are flux materials that help to

purify the gold. The purpose of substance 2 is to liberate the aluminium. Lime is then used to remove

the substance 2. Lime precipitates base metals such as aluminium as gelatinous hydroxides.

Substance 3 is added because the quality of the aluminium had been low grade. During the melting

process flux, slag is taken out for grinding.

Fig-19 Melting

Fig-20 Flux slag

P 2: Pouring

The rest of the melted slag is poured into water.

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Fig-21 Pouring

P 3 Grinding

The process flux is grinded with an iron ball.

P 4: Boiling

Fig-22 Grinding

The solid (gold) pieces from the “Pouring” and the grinded flux are mixed and boiled to remove the

residual water.

P 5: Partition

Nitric acid is added to separate the silver from gold. Silver nitrate is soluble in water and a gold

material precipitates.

Ag + 2HNO3 -> AgNO3+ NO2 + H2O

Fig-23 Partition of gold and silver

P 6: Melting

The gold material is placed in a crucible and melted. Substance 3 is added to absorb impurities. The

flux slag that hardens is removed mechanically. The remaining material in the crucible is pure,

liquified gold. It is poured out and a button is formed with a hammer ike instrument.

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Fig-24 Crucible containing gold after melting

Fig-25 Recovered gold button

The following flowchart illustrates the above-described technique.

Input material

Water Leaching Water vapour

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Substances1 Body components

From "silver- Silver-salt Separation Waste solutionsaltpreparation" Preparations Aluminum foils

Water

Cloth Purification

Lime Silver solution2 Ag - recoveryUnknown Water vapoursubstance NitrogenWater dioxide Nitric acid organic waste

Gold

Fig-26 Simplified flowchart of the „cyanide leaching“.

Mercury amalgamation at Eco BIRD

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The gold recovery with mercury goes back to the 11th century. In the Middle Ages alchemists tried

to produce gold with base metals (which did not work). The mercury amalgamation is based on the

fact that mercury forms an amalgam4 with gold. With this procedure, the gold can be separated from

the other metals present and from impurities. The attraction of mercury is based on the fact that it is

readily available, cheap and efficient in recovering fine-grained gold (Commission of the European

Communities, 2000). It is a quite simple process using only three substances (mercury, nitric acid

and sodium bicarbonate) to recover the gold. However, it is an old technique and no longer used in

modern gold plants because of the known health and environmental problems arising.

Detailed description of the technique

Leaching

The input material is filled in plastic containers (V=approx. 100l). At first water is poured into the

container, than the nitric acid (62%) is added. Throughout this process, the metals (e.g. Cu) which

are contained in the input material, except gold, are dissolved in the solution. Thus, the attaching

parts of the gold pins to the mold are dissolved and the gold pins and flakes are released. The

dissolving takes about 3 hours. During this time, it is stirred from time to time and nitric acid and

some water are added.

2 NO3- + 4 H+ + Cu -> 2 NO2 ↑+ H2O + Cu++

With a sieve (mesh aperture approx. 4 cm x 4 cm) the remaining components are taken out, washed

with water and kept to process them again in the cyanide leaching process. In the bluish solution,

gold flakes remain and copper is dissolved. The solution is filtered through a cloth to abstract the

gold pins. The remaining solution is then put into a big container to recover the copper by adding an

iron to the liquid. The iron is left in the container for several weeks. At the end, the copper sticks to

the iron and can be removed manually.

Fig-27 Lixiviation

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Fig-28 Filtering

4 Amalgam is any mixture or blending of mercury with another metal.

Separation (Amalgamation)

The gold residues are put into a pan, inclusive the cloth used for filtration. Mercury and some drops

of nitric acid are added and mixed in the pan. The resulting alloy of gold and mercury is called

amalgam. The cloth is washed with water and remaining non-gold-components are removed from

the mixture. Sodium Bicarbonate is added to the mixture and the mixture is decanted. The decanted

slag is squeezed through the cloth the excess mercury is recovered. The residue in the cloth is a hard

lump of amalgam with a high concentration of gold. A small amount of mercury and water is added

to the amalgam lump to make it softer. Then the lump is scrunched with a hammer-like instrument.

Fig-29 Goldmercury- amalgam

Purification

Nitric acid is added to the amalgam and the resulting mixture is decanted. Nitric acid dissolves part

of the mercury, which is recovered in a separate process. The decanted mixture is boiled in a

furnace. Because mercury and nitric acid vaporise at a much lower temperature than gold, these two

substances can be removed by heat leaving the gold behind (Beard, 1987). The residual product in

the pan is a yellow gold powder. In a last step, magnetic impurities are sorted out with a magnet.

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Fig-30 Nitrogen dioxide during silver dissolving

Fig-31 Recovered gold powder

The following flowchart illustrates the above-described technique.

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Connectors

Nitric acid Leaching Gas / Fumes

Water Body components

Copper Solution Copper recovery Separation

Mercury Waste solutionNitric acid WasteWater components

Sodium Mercurybicarbonate Purification

Nitric acid Gas / Fumes

Water Mercury solution Mercury recovery

Gold

Fig-32 Simplified flowchart “ of the mercury amalgamation”.

Gold stripping at Surface Chem Finishers

The director of Surface Chem Finishers developed a gold stripping substance with the goal to

conduct a more environmentally sound process than by using cyanide or mercury. The concept is to

dissolve the gold with the solution and collect it with electrolysis.

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Detailed description of the technique

Leaching

The input material is put over night into a substance (gold stripper). During this time, the gold is

eached out of the components. The components are removed from the solution and are washed with

hot water in order to deplete the waste components as good as possible of their gold.

Fig-33 Lixiviation with “gold stripper“

Separation and Purification

The solution is filtered through a “Whatman Filter” and poured into a bucket. The anode and cathode

(titanium) are then put into this bucket. They are connected to a small motor working with 5 V and

0,5 A. Over night, the electrolysis is conducted and the gold is collected at the cathode.

Fig-34 Filtering

The cathode is removed from the solution and dried for 10 min at

178°C.

Fig-35 Electrolysis

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The solid gold on the cathode is dissolved with aqua regia (HCl : HNO3= 3 : 1). This step is done

under an exhaust to protect the worker from inhalation of the toxic fumes.

Au + 4 HCl + HNO3 = HAuCl3 + 2 H2O + NO

Fig-36 Dissolving gold in aqua regia

This solution is filtered again through a “Whatman Filter”. Ferrous sulphate is added in order to

precipitate the gold.

Fe+ + Au2+ -> Fe3+ + Au (s)

To accelerate the process the solution is heated. Purple colloids precipitate.

Fig-37 Heating the sulphate solution

The precipitation is then separated by decanting. The remaining material is washed with water

filtered through a “Borosil Glass”. The Glass is put into a heater to dry the material. The result is a

yellow gold powder.

Fig-38 Gold powder after drying

The following flowchart illustrates the above-described technique.

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Connectors

Leaching Gold Stripper Vapour

Water Body components (BC)

SeparationAqua regia Waste solution 1Water

PurificationFerrous Wastesulphate solution2 Water

Gold

Fig-39 Simplified flowchart of the “gold stripping”.

Quantification

Data collection

During the observations made for the description of the three gold recovery techniques

measurements were conducted to quantify the in- and outputs of the processes. The in- and outputs

were weighed with an electronic scale, measured with a measuring cup or calculated by multiplying

the volume with the density (assumed to be 1000 g / l). To find out the volume, the diameter of the

cylindrical containers and the height of the contained liquid were measured. According to the

received figures the mass flow could be completed applying the law of conservation of mass (Input =

Output), making feasible assumptions and considering the chemical equations. In a further step the

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amounts of in and outputs were converted according to the functional unit “one gram recovered

gold”.

The cyanide leaching and the gold stripping are quantified using provided material.The mercury

amalgamation is only partly quantified during an investigation of the informal facility doing usual

business.

Cyanide leaching at Eco BIRD

The measurements for the different used and produced materials, substances, solutions,

mixtures and vapours are made according to following descriptions:

• All the inputs of this process were measured except the cloth.

• All the liquid outputs and the silver salt (which was also a mixture) were calculated

(volume * density).

• The wet output components were weighed. The estimation was made that the weight of the

dry output components correspond approximately with the weight of the input components

(the amount of leached metals was neglected).

• The amount of “water vapour 1” results from subtracting the weight of the input

components from the wet weight of the output components.

• The estimations for the produced nitrogen dioxide were made according to the chemical

equation of the silver dissolution with nitric acid.

• The deficiency of the mass in the flowchart was identified that it is most probably the

water, which had vaporised (especially during heating). This is proved plausible considering

that the evaporation enthalpy of water is 2257 kJ / kg, charcoal produces 25 MJ / kg and

assuming a 30 % efficiency factor. Following for 4,91 kg (4880 g + 30 g) water vapour

approximately 1,3 kg charcoal is used.

The quantified mass flows are shown in the subsequent flowcharts.

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Input material 1

Energy (coal) L 1: Lixiviation water vapour

Hot water

Substance 1

Water L 2: Sieving/Washing body components water vapour

From “silver-salt- silver-salt S 1 : Gold formationPreparation” aluminum foils Water Cloth S 2: decantation/ waste solution Filtering

Energy (coal) Lime P 1: Melting Substance 2 Substance 3 P 2: Pouring Process flux

Water P 3: Grinding silver solution 2 Ag- Recovery Solid(gold) Pieces P 4: Boiling Water vapour

Water P 5: Partition silver solution 2 Ag- Recovery Nitric acid nitrogen dioxide

Substance 3 P 6: Melting organic waste

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Gold

Fig-40 Quantified flowchart of the cyanide leaching (main process); unit of numbers is gram.Chapter 2 Gold recovery techniques and hazards

Energy (coal) Silver PS 1: Heating Nitrogen dioxide Nitric acid Silver

Water

Sodium chloride PS 2: Precipitation Water

Hot water PS 3: Decantation

Water PS 4: Mixing Silver-salt

Unknown salt silver solution 1 Ag-recovery

Caustic soda

Fig-41 Preparation of silver-salt used in the main process of the cyanide leaching; unit ofnumbers is gram.

The following tables (Table 6and Table 7) give an overview of all the in- and outputs and are

quantified according to the functional unit (“one gram recovered gold”). In addition, the further

destinations of the outputs are noted.

Table 6: Input materials of the cyanide leaching per gram recovered gold

Input g / g gold

Input material 2,07E+04

Water 5,36E+04

Substance 1 (containing cyanide) 1,85E+02

Aluminium 4,67E+01

Nitric acid 6,77E+02

Lime 4,67E+01

Silver 1,17E+02

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Sodium chloride 3,93E+02

Caustic soda 2,45E+02

Unknown salt 1,35E+02

Unknown substances (2, 3) 2,00E+01

Table 7: Output materials of the cyanide leaching per gram recovered gold

Output g / g gold Destination

Body components 2,07E+04 Solid waste stream

Water vapour 8,41E+03 Air

Waste solution 3,02E+04 Drain

Silver solutions 1,68E+04 Recovery

Fumes (Nitrogen dioxide) 8,00E+01 Air

Silver 6,67E+00 Process cycle

Gold 1,00E+00 Sale

The silver solutions are further treated with a silver recovery technique. This technique is not

included in the system boundary. However, a short description of the process is given in the

subsequent paragraph.

Silver Recovery

The silver from the silver solutions (output) is recovered using sodium chloride, which reacts with

silver producing silver chloride. In a further step iron is added which precipitates the silver, acting as

a reducing agent. The precipitation is then melted and solid silver is recovered. Using this procedure

in the above process 50 grams of silver, were recovered. Thus per gram of produced gold 83 grams

of silver are recovered. This means that during the cyanide leaching 27 grams of silver are lost per

gram recovered gold.

Mercury amalgamation at Eco BIRD

This technique was investigated during a visit of the informal facility doing usual business. The in-

and outputs were only partly measured. The input material of the observed process was connectors

assumingly from PWBs of telephones. From 14,3 kilograms of connectors 54 grams of gold was

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recovered. During this technique, more than 130 g of mercury was used. The other used materials

have not been measured. The in- and outputs and their further destinations are listed below.

Table 8: Input materials of the mercury amalgamation per gram recovered gold

Input g / g goldInput material (connectors) 2,64E+02Mercury 3,59E+00

Sodium bicarbonateWater

Table 9: Output materials of the mercury amalgamation per gram recovered gold

Output g / g gold DestinationBody components Solid waste streamGas / Fumes (i.e. water vapour, nitrogen dioxide) AirCopper solution RecoveryWaste solution DrainMercury solution RecoveryMercury 0,07E+00 Process cycleGold 1,00E+00 Sale

Gold stripping at Surface Chem Finishers

The measurements for the different in- and outputs are made according to following descriptions:

• All the inputs of this process were measured except the water used for the purification.

• The wet output components were weighed. The estimation was made that the weight of the

dry output components correspond approximately with the weight of the input components

(the amount of leached metals was neglected).

• The amount of the vapour results from subtracting the weight of the input components

from the wet weight of the output components.

• The waste solution 1 was measured using a measuring cup.

• The waste solution 2 was not measured.

The processes and the quantified in- and outputs of gold stripping, showing the mass flow as it was

determined during the on site observation. A flowchart illustrating the different process steps

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Connectors

Gold stripper Leaching vapour

Water body components

aqua regia separation waste solution

water

ferrous purification waste sulphate solution water gold

Fig-42 Simplified and quantified flowchart of the “gold stripping”; unit of numbers is gram.

The following tables (Table 10 and Table 11) give an overview of all the in- and outputs of the

process and their further destinations are noted.

Table 10: Input materials of the “gold stripping” per gram recovered gold

Input (g) Per g goldInput material 6,48E+03Water >2,75E+04Gold Stripper 1,23E+03Hydrochloric acid 5,93E+02Nitric acid 2,16E+02Ferrous sulphate 4,07E+02

Table 11: Output materials of the “gold stripping” per gram recovered gold

Output (g) Per g gold DestinationBody components 6,48E+03 Solid waste streamVapour 3,09E+02 Air

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Waste solution 1 1,48E+04 Treatment plantWaste solution 2 >1,48E+04 Treatment plantGold 1,00E+00 Gold plating

Interpretation

Based on the system descriptions and quantifications the critical outputs, concerning the

environment and human health, of the three gold recovery processes were identified. These

hazard-“hot spots” are listed and described for each process. From some of these critical outputs

samples were taken and tested for a range of metals that are known to have a high potential to bio-

accumulate in the environment. Additional on site observations during the conducted processes are

qualitatively discussed.

Cyanide leaching at Eco BIRD

Major hazard-“hot spots”

1. Fumes: The most obvious contamination during the observation was the nitrogen dioxide, a red-

brown fume that was generated during the dissolution of silver, which irritated the eyes and

provoked dizziness. The corresponding chemical equation is:

Ag + 2 HNO3 -> AgNO3 + NO2 ↑+ H2O.

2. Waste solution: The waste solution is poured untreated into the drain. Since there is no

canalisation system, which ends up in a wastewater treatment plant the waste solution ends up

directly into the environment (water, soil and air) and can pollute the adjacent communities and

waters.

3. Body components: The body components probably end up in the solid waste stream. This means

that they are piled up on the streets for some time and in the best-case end up in the landfill. In both

cases over a certain amount of time, the contents in the body components will be released to the

environment. A study from Jang and Townsend (2003) showed that lead will leach out from PWB

when landfilled. Samples of the waste solution and the body components were collected and tested

for the concentration of a range of metals. The most relevant metals to the environment according to

Smidt (2006) and their concentration in the body components, respectively in the waste solution are

presented in Table 13 and Table 12. In addition, aluminium is also listed in Table 2.7 because of its

elevated concentration in the wastewater.

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Table 12: Metal concentrations in the waste solution of the “cyanide leaching”

Element Concentration (ppm) Stdev [ppm]Aluminium (Al) 1315 55

Arsenic (As) <0.5Cadmium (Cd) <1

Copper (Cu) 185 6Mercury (Hg) <0.5

Nickel (Ni) 9Lead (Pb) 4Zinc (Zn) 17 1

Table 13: Metal concentration in the body components of the “cyanide leaching”

Element Concentration (ppm) Stdev (ppm)Copper (Cu) 229250 2333Nickel (Ni) 3200 141Lead (Pb) 22650 1626Tin (Sb) 5100 283Zinc (Zn) 23950 4596

Additional on site observations

The handling of the materials, which contain cyanide salts and nitric acid, is very frivolous and no

personal protection like gloves, goggles or masks are used. All of the workers have small burns in

the skin of the palms and a yellowish discoloration of skin and nails which are most probably

symptoms of the contact with nitric acid. Beverages and food are consumed while handling the

different and often hazardous substances. Thus, the substances can enter the body through absorption

or ingestion.

Comparison to the Swiss legislation

To give a quantitative statement to the possible hazards the results of the sampling are put into

relation with the allowed concentrations to discharge industry effluents into water in Switzerland,

according to Annex 3, GschV (Schweizerische Eidgenossenschaft, 1998). The Swiss “regulation of

water pollution control” limits the effluent concentration from industry, amongst others, of the pH,

eight metals and the free cyanide ion. These metals (plus mercury, molybdenum and thallium) are

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the most relevant heavy metals to the environment. In the following table, the requirements of the

Swiss regulation are compared with the concentration of the wastewater of the “cyanide leaching” at

Eco BIRD. The ratio indicates the deviation of the values of the waste effluent from the cyanide

leaching conducted at Eco BIRD, in Bangalore, to the Swiss thresholds.

Table 14: Comparing the thresholds of the Swiss legislation of industrial

waste water with the found concentration in the waste solution of the “cyanide leaching”

Parameter Request GschV Ratio Waste water Eco BIRDpH-value 6.5 to 9.0 12

Arsenic (As) 0.1 mg / l < 5 <0.5 mg / lLead (Pb) 0.5 mg / l 8 4 mg / l

Cadmium (Cd) 0.1 mg / l < 10 <1 mg / lChromium (Cr) 2 mg / l n.a.

Cobalt (Co) 0.5 mg / l n.a.Copper (Cu) 0.5 mg / l 370 185 mg / lNickel (Ni) 2 mg / l 4.5 9 mg / lZinc (Zn) 2 mg / l 8.5 17 mg / l

The concentration of copper in Eco BIRD’s effluent exceeds Swiss industrial wastewater thresholds

370 times. In addition, the concentrations of all the other heavy metals are above the Swiss

thresholds. These high concentrations of metals in the effluent are because the cyanide salt, which is

used to dissolve the gold, also dissolves all other metals. Another concern is the high pH of the

tested effluent, which makes the water environmentally hazardous.

Mercury amalgamation at Eco BIRD

Major hazard-“hot spots”

1. Fumes: The most obvious exposure to a hazard has been observed during the first step in the

mercury amalgamation process when almost the whole workplace had been covered with a redish

fume. Nitrogen dioxide is produced, corresponding to the chemical equation:

2 NO3- + 4 H+ + Cu -> 2 NO2 + H2O + Cu++.

It was observed that the mercury is heated and vaporises during the purification. Thus, it ends up in

the air. The production of gold using mercury amalgamation is stated tobe an important source of

anthropogenic releases of mercury (UNEP, 2002). It is known that during this process extensive

amounts of mercury end up in the atmosphere and biosphere. For example: The mean value of

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mercury loss in mines of the Madeira Rivers, Brazil is 1,32 kg mercury per 1 kg gold (Stüben, 2004).

In the Mindao Region, Philippines there is a mean value of mercury loss of 5 kg Hg/kg Au. The

exposition to mercury during gold recovery in the Philippines has been studied by Maydl (2004).

The practice is discouraged, because “…poor management of both liquid mercury and the vapour

arising from volatilising mercury contributes to serious health problems…” (Logsdon et al., 1999).

2. Waste solution: It is known that from the waste solution copper is recovered in a further process.

Therefore, the copper concentration is probably lower than it is measured in the waste solution of the

“cyanide leaching”. However, after the copper recovery the solution is also poured into the drain. An

important difference between this solution and the before described solution is the acidity. Using

such a high amount of nitric acid will lead to a low pH. The acidification of the water and sediments

make toxic metals more mobile and therefore more likely to have toxic effects on aquatic life

(Brigden et al., 2005).

3. Body components: The body components of the “mercury amalgamation” are sometimes again

processed with the “cyanide leaching”. Afterwards they are also dumped in the streets and the metals

that are still contained in the components will leach out sooner or later.

Additional on site observations

See additional on site information for cyanide leaching in the above subchapter.

Gold stripping at Surface Chem Finishers

Major hazard-“hot spots”

1. Waste solution: The waste solution is given to an effluent treatment plant (PAI & PAI Chemicals

(India) Pvt. Ltd.), thus it will be treated and the hazardous substances within should be eliminated.

2. Body components: The body components also land in the solid waste stream. As mentioned

before several (heavy) metals are still present within the remaining components and leach out

eventually. A sample from the body components could be taken and was tested for the concentration

of a range of metals.

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Table 15: Metal concentration in the body components of the “gold stripping”

Element Concentration (ppm)Copper (Cu) 223000Nickel (Ni) 5000Lead (Pb) 2000Tin (Sb) 11000Zinc (Zn) 33000

Additional on site observations

During the on site observations no obvious hazards could be observed. The handling of the

substances has been very careful and both an exhaust system and personal protection equipment has

been used.

Discussion

Suitability of the method

The method is based on the scientific concept of the mass flow analysis and was adjusted according

to the encountered situations and the available resources. It has been a suitable tool to make a

quantitative evaluation of the processes. The method helps increase the knowledge of the conducted

processes and the gained data are transparent and objective. “One of the major problems in using this

method (MFA) in regions in developing countries is the availability of reliable data” (Binder et al.,

2001). Addressing this problem experimental data is collected in addition to literature research and

interviews. Within the time limits of this thesis and having a certain amount of provided material,

only two of the three encountered gold recovery techniques could be fully quantified. Furthermore, a

repetition and improvement of the measurements was not possible. Thus, it is a momentary

recording of the process using the provided material. This leads to the fact that statistical procedures

cannot be applied to give the data more weight. Nevertheless, it was possible to describe all

investigated gold recovery processes qualitatively in detail and to quantify two of the processes.

Evaluation of the systems

In the following subchapters, an overview of the conducted techniques is presented. Further it is

discussed whether the characterisation of the different techniques presented in this thesis can be

regarded as representative in general for these techniques in Bangalore. This is a very important

issue as the investigation is based only on a few measurements. Consequently, this might not be

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sufficient to use the data for the definition of standard processes. Despite of the restrictions in

sampling and measuring the identification of the ‘hot spots’ was possible.

INPUT MATERIAL

Water

Cyanide Fumes (NO2)

Nitric acid

Aluminum Cyanide leaching Waste solution environment

Silver

Other Body components

Substances

Gold

Fig-43 Major flows of the “cyanide leaching”.

Discussion

In the investigated experimental technique the same processes, containers, etc. are used as in a usual

cyanide leaching technique. The quantity of the provided input material was below the usual

quantity. Nevertheless, the investigation gives adequate indications of the used amount of materials

in a usual technique conducted in this facility. To recover one gram of gold in the investigated

technique approximately 200 grams of a substance containing cyanide was used. In another observed

cyanide leaching technique, conducted at the same unit doing usual business, they used 10 grams of

the cyanide containing substance to recover one gram of gold. With the chemical equation

4 Au(s) + 8 CN-(aq) + O2(g) + 2 H2O(l) 4 Au(CN)2-(aq) + 4 OH-(aq),

it can be calculated that approximately 0,66 g of potassium cyanide, respectively 0,5 g of sodium

cyanide would be needed to leach out one g of gold. Explanations of the much higher amount of

cyanide used in the processes could be:

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• The concentration of cyanide salt in the substance is low.

• The input material contains many other metals, which leads to a high cyanide use.

Gold has a high standard reduction potential and is therefore the last metal to be dissolved.

Thus, to calculate the exact needed amount of cyanide the exact composition of the input material

would have to be known. Hence, the amount of needed cyanide increases with each present metal.

This could explain the conducted segregation for apparent gold before the material enters the gold

leaching process.

It also leads to the assumption that rather more cyanide is used as required to make sure all the gold

is dissolved. In the investigated process, 21 kg of input material to recover one gram of recovered

gold is needed. In another observed process, 3 kg of input material per one gram of recovered gold is

used and from the estimated figures, the average recovery rate would be one g gold per 250 g of

input material. This wide-ranging amount of input material used to recover one gram of gold might

be because of the different gold content in the input material and because of different people

conducting the process. A piece in the process, which is surprising, is the preparation of silver-salt

(see PS 1 – PS 3). Theoretically, silver-salt is not needed to precipitate/form the gold (see S 1 (ETH)

and literature resources, gold can be precipitated using only zinc or aluminium. Due to the addition

of silver-salt 27 grams of silver are lost per gram recovered gold, which is a lot considering that it is

a precious metal and thus valuable.

Possible explanations could be:

• In the first process, excess cyanide is added to be sure all possible gold is dissolved.

The silver salt is used to bind the excess cyanide in the “Gold formation” process step

(S 1). Maybe it is cheaper to add the silver that can be recovered and used again than

to add more aluminium or zinc to precipitate the gold (Schönberg, 2006)

• The used silver is not pure enough to be sold and is therefore a waste product that

has no better use than to decrease the amount of aluminium needed in the separation

process.

• “The purpose of adding silver is to obtain a more impure gold alloy. If there is more

silver than gold present in the alloy, it is easier to separate them” (Parthasarathy,

2006).

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Regarding the purification process (see P 1 to P 6), the question is raised why it is composed of so

many steps. The essential steps are the melting (P 6) and the partition (P 5), where the gold is

separated from silver and other impurities. Theoretically, the process could be simplified

concentrating on the essential steps. However, the experience of the workers goes back several

generations and the made assumptions would have to be discussed with them and evaluated.

Mercury amalgamation at Eco BIRD

Overview

Input material

Water Fumes (NO2, mercury vapour)

Mercury mercury waste Environment amalgamation solution

Sodium Body bicarbonate components

Gold Fig-44 Major flows of the “mercury amalgamation”.

Discussion

During the mercury amalgamation in the worst case 3,5 grams of mercury is lost per gram recovered

gold. This is a very dangerous loss to health and environment. Some of this mercury is recovered in

a subsequent mercury recovery technique, which has not been further investigated. However, the

loss due to vaporisation could be easily decreased by collecting and condensing the mercury vapour

as it is done in several gold mines using this process.

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Gold stripping at Surface Chem Finishers

Overview

Input material

Water Waste Gold solutionStripper cyanide

Leaching environmentAqua regia BodyFerrous componentssulphate Gold

Fig-45 Major flows of the “gold stripping”.

Discussion

The conducted experimental technique was a miniaturised example of the usual technique. Usually

around 100 kg of input material is treated together. Because of the small amount of material, some

adaptations had to be made: no additional oxygen was pumped into the solution, which is left over

night; the cathode was titanium instead of stainless steel; the cathode was put directly into aqua regia

(usually the gold is scraped off before). According to the director of the facility, the experiment is

nevertheless comparable with his usual technique.

Taking the figures given from the Engineer of E-Parisaraa 2 kg input material are needed to recover

one g gold. In the experiment 6,5 kg of input material would be needed to recover one gram gold.

This is an indication that the input material of the experiment is a little less concentrated on gold or

the gold is easier to leach out when the quantity of used material and substance is higher. In order to

take the right amount and not waste anything the different auxiliary substances are always measured

carefully. Thus, it seems that this process is standardised and it is known that qualitative checks are

regularly executed by the director of the facility.

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Monitors

Monitors are much sought after by scrap dealers as they contain good quantity of copper yoke,

besides circuit board and picture tube. The different recovery processes observed in MMR are given

below. Dissembling of CRT and Extraction of Components The first step in monitor recycling

involves physical removal of plastic casing, picture tube (cathode ray tube), copper yoke and plates.

The intact and functional CRT is used for the manufacture of colour and black & white televisions

for local brands. Re-gunning is possible only for those monitors whose terminal pin (diode pin) of

electron gun has not broken in the process of removing yoke from gun.

Recovery of Glass from CRT

Defective CRT is broken down to recover iron frames from the glass funnel as shown in Figure

46,47. The iron frames are found only in color CRTs and not in black & white monitors. The glasses

and iron frames from picture tubes are given to waste traders. Yoke Core,

Yoke Core, Metallic Core and Copper from Transformers

The copper and yoke core recovered from yoke coils found around the picture tube end is sold to

copper smelters and re-winders as shown in Figure 48 and Figure49. Apart from the yoke, copper

and metallic core is also recovered from transformers mounted on the circuit board of the computer.

The circuit tray also contains a number of condensers of different sizes. Depending upon their

condition and demand they again enter into the secondary market for reuse. If they are defective,

they are sold along with the motherboard. Rare Earth Core of Transformer and Copper These small

transistors and rare earth transformers are boiled in water with small amount of caustic soda, which

results in loosing of joint between the core resulting in core and copper extraction as shown in

Figure 11.

Copper Extraction from Wires

Two kinds of processes are being followed under this category as listed below:

1. Manual drawing of wires for copper

2. Extraction of copper by burning the wire

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Plastic casing of ether ABS or high Separated for sale

Opening the plastic case CRT with PWB and other casing

CRT of breakage separation of PWB York and CRT

York for core and copper extraction separated PWB

Fig-46 Dissembling of CRT and Extraction of Components

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Fig-47.a Glass Recovery by CRT Breaking

York with component

York core cutting of copper form core is shown

Copper

Fig-47.b Extraction of Yoke Core and Copper

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Metallic transformer cutting of cooper with nail and hammer

Metallic core copper

Fig-48 Extraction of Metallic Core of Transformer and Copper

Rear earth transformer boiling of transformer rear earth core

Copper

Fig-49 Extraction of Rare Earth Core of Transformer and Copper

Manual drawing of Wires for Copper

Under this process with the use of knife the edge of wire is cut and then with the help of pliers the

copper is extracted from PVC as shown in Figure 50. The process is as shown below copper goes for

sale to copper smelters and PVC is used for plastic graining.

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copper

Computer wire cutting the wire edge and pull the copper

PVC

Fig-50 Computer Cable

Plastic Shredding and Graining

The plastic casings of monitors are made either of PVC (polyvinyl chloride) or ABS (acrylonitrile-

butadiene styrene). PVC was used more commonly in the early models of computers. Now

computer-manufacturing companies have shifted to ABS plastic in the production of monitors.

Though both types of plastics are currently being recycled as shown in Figure 51, the PVC one

cannot be recycled. This is due to the high percentage of silicate being added for making it fire

retardant. The silicate plastic often ends up at kilns as an alternate source of energy. The plastic

casing is recycled into EBS or High Impact Plastic. These kinds of plastics are frequently used in

manufacturing toys.

Dismantling of compressor & segregation of compressor & cooling box

Refrigerator is dismantled for metal recovery, plastic recovery, insulating material

and compressor as shown in Figure 51.

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In 02: manual labor Ou 01: separated cooling box

In 01 end life of refrigerator P 01: manual breaking using hammer and punches

Ou 02: segregation of insulating material

Ou 03: separated compressor

Fig-51 Dismantling of Refrigerator and Segregation of Compressor and

Cooling Box

Disposal

It has been observed in many parts of the world that the most common practice of disposing e-waste

is simply throwing it away with domestic waste, which eventually ends up in landfills or gets

incinerated. However, this may result in several environmental hazards and hence, the waste must be

disposed off in a proper manner.

Fig-52 Plastic Shredding

Advantages of Recycling e-waste:

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· It will give way to Perfect Management of E-Waste.

· As there will be virtually no landfilling or incineration, the hazards to the environment will be

avoided.

· Waste disposal costs will be reduced for organizations handling their own EWaste.

· It will generate good quantity of raw materials for various other industries. Moreover, the cost of

this raw material will be much less than that obtained from its original source.

· Widely used metals like copper, platinum have to be dug out from their ores. Acquiring them this

way will not only be a cheaper, less time consuming mean, but will also result in reduction of waste,

and its hazards by reuse.

· Plastics can be reused relatively many times. So recycling them from E-Waste makes use of this

advantage of plastics.

· It will have better and safer working conditions relative to backyard stripping corporations. This

means protected means of dismantling and recycling of EWaste.

· It will generate many employment opportunities for people from many disciplines.

13. Responsibilities of government, industries, and citizen.

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Considering the severity of the problem, it is imperative that certain management options be adopted

to handle the bulk e-wastes. Following are some of the management options suggested for the

government, industries and the public.

Responsibilities of the Government

(i) Governments should set up regulatory agencies in each district, which are vested with the

responsibility of co-coordinating and consolidating the regulatory functions of the various

government authorities regarding hazardous substances.

(ii) Governments should be responsible for providing an adequate system of laws, controls and

administrative procedures for hazardous waste management (Third World Network. 1991). Existing

laws concerning e-waste disposal be reviewed and revamped. A comprehensive law that provides e-

waste regulation and management and proper disposal of hazardous wastes is required. Such a law

should empower the agency to control, supervise and regulate the relevant activities of government

departments.

Under this law, the agency concerned should

Collect basic information on the materials from manufacturers, processors and importers

and to maintain an inventory of these materials. The information should include toxicity

and potential harmful effects.

Identify potentially harmful substances and require the industry to test them for adverse

health and environmental effects.

Control risks from manufacture, processing, distribution, use and disposal of electronic

wastes.

Encourage beneficial reuse of "e-waste" and encouraging business activities that use

waste". Set up programs so as to promote recycling among citizens and businesses.

Educate e-waste generators on reuse/recycling options

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(iii) Governments must encourage research into the development and standard of hazardous waste

management, environmental monitoring and the regulation of hazardous waste-disposal.

(iv) Governments should enforce strict regulations against dumping e-waste in the country by

outsiders. Where the laws are flouted, stringent penalties must be imposed. In particular, custodial

sentences should be preferred to paltry fines, which these outsiders / foreign nationals can pay.

(v) Governments should enforce strict regulations and heavy fines levied on industries, which do not

practice waste prevention and recovery in the production facilities.

(vi) Polluter pays principle and extended producer responsibility should be adopted.

(vii) Governments should encourage and support NGOs and other organizations to involve actively

in solving the nation's e-waste problems.

(viii) Uncontrolled dumping is an unsatisfactory method for disposal of hazardous waste and should

be phased out.

(viii) Governments should explore opportunities to partner with manufacturers and retailers to

provide recycling services.

Responsibility and Role of industries

1. Generators of wastes should take responsibility to determine the output characteristics of

wastes and if hazardous, should provide management options.

2. All personnel involved in handling e-waste in industries including those at the policy,

management, control and operational levels, should be properly qualified and trained.

Companies can adopt their own policies while handling

e-wastes. Some are given below:

Use label materials to assist in recycling (particularly plastics).

Standardize components for easy disassembly.

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Re-evaluate 'cheap products' use, make product cycle 'cheap' and so that it

has no inherent value that would encourage a recycling infrastructure.

Create computer components and peripherals of biodegradable materials.

Utilize technology sharing particularly for manufacturing and de

manufacturing.

Encourage / promote / require green procurement for corporate buyers.

Look at green packaging options.

3. Companies can and should adopt waste minimization techniques, which will make a

significant reduction in the quantity of e-waste generated and thereby lessening the impact on

the environment. It is a "reverse production" system that designs infrastructure to recover and

reuse every material contained within e-wastes metals such as lead, copper, aluminum and

gold, and various plastics, glass and wire. Such a "closed loop" manufacturing and recovery

system offers a win-win situation for everyone, less of the Earth will be mined for raw

materials, and groundwater will be protected, researchers explain.

4. Manufacturers, distributors, and retailers should undertake the responsibility of

recycling/disposal of their own products.

5. Manufacturers of computer monitors, television sets and other electronic devices

containing hazardous materials must be responsible for educating consumers and the general

public regarding the potential threat to public health and the environment posed by their

products. At minimum, all computer monitors, television sets and other electronic devices

containing hazardous materials must be clearly labeled to identify environmental hazards and

proper materials management.

Responsibilities of the Citizen

Waste prevention is perhaps more preferred to any other waste management option including

recycling. Donating electronics for reuse extends the lives of valuable products and keeps them out

of the waste management system for a longer time. But care should be taken while donating such

items i.e. the items should be in working condition.

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Reuse, in addition to being an environmentally preferable alternative, also benefits society. By

donating used electronics, schools, non-profit organizations, and lower-income families can afford to

use equipment that they otherwise could not afford.

E-wastes should never be disposed with garbage and other household wastes. This should be

segregated at the site and sold or donated to various organizations.

While buying electronic products opt for those that:

o are made with fewer toxic constituents

o use recycled content

o are energy efficient

o are designed for easy upgrading or disassembly

o utilize minimal packaging

o offer leasing or take back options

o have been certified by regulatory authorities. Customers should

opt for upgrading their computers or other electronic items to the

latest versions rather than buying new equipments.

NGOs should adopt a participatory approach in management of e-wastes.

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14. E-Waste Policy for India

Under the aegis of ASSOCHAM Expert Committee on Environment a Seminar on “E-Waste Policy

for India” was held in New Delhi on May 26, 2006. Designed with the aim of spreading awareness

on the hazards of E-waste in the country, discussing E-waste management & disposal options and

inviting inputs for framing an E-Waste policy for the country, this well-attended Seminar had

discussants representing industry, research and development institutions, environmental

organizations and consultants, legal practitioners, and E-waste recyclers.

The Keynote Speaker in the Seminar was Dr. R.S. Mahawar, Additional Director Central Pollution

Control Board.

Eminent speakers, such as Mr. P. Ravindranath, Director, Government and Public Affairs, Hewlett-

Packard India,

Mr. Amit Jain, Management Director – India Operations, IRG SSA,

Dr. T.K. Joshi, Director, Centre for Occupational and Environmental Health, Government of NCT of

Delhi,

Mr. Gaurang Baxi, Manager, Corporate HSE, Kodak India,

Mr. Rahul Sharma, Director, TRI International Limited,

Dr. S.K. Pachauri, Former Director General, National Productivity Council and Ex-Secretary to the

Government of India,

Mr. M.S. Nagar, Ex CMD, Indian Rare Earths Ltd. and former Consultant, Ministry of Environment

and Forests, Government of India,

Dr. Usha Dar, President, Council of Industrial Environmental Relations in Delhi, shared their views

and experiences in this Seminar.

In the backdrop of resurgent growth of the Indian economy and greater reliance on electronic

hardware for household, industrial and office automation, commitment to eco-responsibility was

seen as a sine qua non for the society, economy and the environment.

There was unanimity that electronic waste containing substances like lead, cadmium, mercury,

polyvinyl chloride (PVC) has immense potential to cause enormous harm to human health and

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environment, if not disposed properly since the extant prescriptions for its disposal and safeguard

were inadequate. Thus, the imperative need for early formulation of a holistic E-waste legislation

which will eventually lead to enabling policy. It was consensually agreed that such a policy must

appropriately reflect the concerns of various stakeholders besides views of practitioners in the field,

both in the organized and the unorganized sector.

The deliberations in the Seminar highlighted the likely enormity in the magnitude of E-waste to be

generated every year (approx 1,50,000 tonnes). Issues relating to poor sensitisation about this sector,

low organized recycling, cross-border flow of waste equipment into India, limited reach out and

awareness regarding disposal, after determining end of useful life, and lack of coordination between

various authorities responsible for E-waste management and disposal including the non-involvement

of municipalities in E-waste management were discussed threadbare. The emerging global trend of

producer responsibility for disposal after useful life becoming the governing principle globally by

the year 2008 and lack of steps in India in this regard were cited prominently during the

deliberations.

Conscious of the prevalent uncertainties regarding “when, where, and how” to dispose hazardous,

harmful E-waste, the role of informal sector in the process and the necessity of introducing a

comprehensive framework early, ASSOCHAM affirms its commitment to assist the Government in

carving out an inclusive E-waste management policy, as for meeting the need for finding an “India

Unique Solution”, that strikes a visionary balance between precepts and praxis for sustainable

management of E-waste, such a policy alone can bring the desired paradigm shift.

ASSOCHAM, in recognition of this urgent necessity of proper management of E-waste in the

country therefore recommends for consideration of the Government the following :

1. Promulgate an all-embracing national E-waste Management law, and an all-encompassing

policy thereunder, for substituting the existing Hazardous Waste (Management and Handling)

Rules 2003, as the latter are not comprehensive enough to attain the aforesaid objectives.

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2. Initiate the process for complete national level assessment, covering all the cities and all the

sectors. Such base line study must envelope inventories, existing technical and policy

measures required for emergence of national E-waste policy/strategy and action plan for eco-

friendly, economic E-waste management. The study should also culminate in identifying

potentially harmful substances and testing them for adverse health and environmental effects

for suggesting precautionary measures.

3. Create a public-private participatory forum of decision making, problem resolution in E-

waste management. This could be a Working Group comprising Regulatory Agencies,

NGOs, Industry Associations, experts etc. to keep pace with the temporal and spatial changes

in structure and content of E-waste. This Working Group can be the feedback providing

mechanism to the National Nodal Authority in the Government that will periodically review

the existing rules, plans and strategies for E-waste management.

4. ASSOCHAM as a Knowledge Chamber advocates creation of knowledge data base on end

of useful life determination, anticipating the risks, ways of preventing and protecting from

likely damage and safe and timely disposal of E-waste. It accordingly urges the Government

to promote Information, Education and Communication (IEC) activities in schools, colleges,

industry etc. to enhance the knowledge base on E-waste management using the PPP mode.

5. Creation of data base on best global practices and failure analyses for development and

deployment of efficacious E-waste management and disposal practices within the country.

6. Device ways and means to encourage beneficial reuse/recycling of E-waste, catalyzing

business activities that use E-waste.

7. Formulate and regulate occupational health safety norms for the E-waste recycling, now

mainly confined to the informal sector.

8. Review the trade policy and exim classification codes to plug the loopholes often being

misused for cross-border dumping of E-waste into India.

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9. Insist on stringent enforcement against wanton infringement of Basel convention and E-waste

dumping by preferring incarceration over monetary penalties for demonstrating deterrent

impact.

10. Foster partnership with manufacturers and retailers for recycling services by creating an

enabling environment so as dispose E-waste scientifically at economic costs.

11. Mandate sustained capacity building for industrial E-waste handling for policy makers,

managers, controllers and operators. Enhance consumer awareness regarding the potential

threat to public health and environment by electronic products, if not disposed properly.

12. Enforce labeling of all computer monitors, television sets and other household/industrial

electronic devices for declaration of hazardous material contents with a view to identifying

environmental hazards and ensuring proper material management and E-waste disposal.

13. Announce incentives for growth of E-waste disposal agencies so that remediation of

environmental damage, threats of irreversible loss and lack of scientific knowledge do not

anymore pose hazards to human health and environment. Simultaneously, as a proactive

step, municipal bodies must be involved in the disposal of e-waste lest it becomes too late for

their intervention, should large handling volumes necessitate it.

14. Consider gradual introduction of enhanced producer responsibility into Indian process,

practices and procedures so that preventive accountability gains preponderance over polluter

immunity.

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15. CONCLUSION

The requirement and usage of electronic equipments is increasing day by day, as new, cheaper and

better technologies replace the old ones. This renders the old equipments useless, and leaving huge

amounts of electronic waste behind. However, this waste still has valuable metals and substances

that can be used. Consequently, the dismantling and reuse of E-waste components has become quite

a lucrative industry. But a only a fraction of the total amount of E-Waste is found to be recycled, and

the rest discarded along with domestic waste. By discarding the rest of the waste, not only is the

environment being contaminated with hazardous substances, but also many reusable valuable

materials get are wasted.

The materials recovered from E-Waste are often in richer quantity than their original sources. In

addition to that, their recovery is much cheaper as well. Hence E-Waste can be considered to be a

rich yet cheap source of many valuable substances like plastics, gold, copper etc. This implies that

with better collection and processing techniques, an E-Waste recycling industry, set up with

contributions from the government and the consumers, can generate remarkable revenue, at the same

time providing a sustainable E-Waste management technique

16. REFERENCES

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HTTP://WWW.IIMM.ORG/NATIONAL_EXECUTIVE.HTM

HTTP://WWW.GOOGLE.CO.IN

HTTP://WWW.SCRIBD.COM

HTTP://WGBIS.CES.IISC.ERNET.IN/ENERGY/PAPER/RESEARCHPAPER.HTML

HTTP://EWASTEGUIDE.INFO/SYSTEM/FILES/KELLER_2006_ETH-EMPA.PDF

HTTP://WWW.NRCAN.GC.CA/MMS-SMM/BUSI-INDU/RAD-RAD/PDF/ELEC-SFR-ENG.PDF

112 E-waste recycling in India