Group members : Student ID :

Susan Silvarajoo 112415012

Nuramelia Syahirah bt Kushaini 112415011

Nur Halimah Hamizah binti Hamdan B10090051

Nick Othman Abdullah B12090007

Field Trip Report to Indah Water Konsortium (IWK) Sdn. Bhd

Due date : 25 / 11 / 2013

Lecturer’s name : Ms. Sherina Binti Kamal

Field Trip Report to Indah Water Konsortium (IWK) Sdn. Bhd, Putrajaya

Sewage Treatment Plant, Indah Water Konsortium (IWK), Putrajaya

Company History

Indah Water Konsortium (IWK) is a company owned by Minister of Finance Incorporated.

IWK is Malaysia's national sewerage company in developing and maintaining a modern and

efficient sewerage system for all the Malaysians. Indah Water has taken the sewerage services

from local authorities in all areas except the states of Sabah, Sarawak, Kelantan and the Majlis

Perbandaran Johor Bahru, Majlis Perbandaran Pasir Gudang, Ketengah and Kejora. An efficient

sewerage system is vital for the country to ensure that wastewater is treated before being

discharged into our rivers to help preserve the country's waste resources, protect public health

and provide a cleaner and safer environment.

Introduction

Sewage pollution is defined as ‘Loadings’ to the environment which exceeds the prescribed

upper limits. Sewage pollution used two most important parameters, they are Biological Oxygen

Demand (BOD) and Suspended Solid (SS). BOD is defined as a measure of the amount of

oxygen that sewage consumes over a given time. High BOD, more rapidly sewage will consume

all the naturally-dissolved oxygen in streams, rivers and lakes, thus killing off all aquatic life.

Furthermore, SS is a measure of the undissolved material in sewage. Higher SS leads to sludge

deposits in the waterways, thus causing significant environmental deterioration.

Main causes of deterioration of river water quality are discharges of sewage and domestic

wastewater, discharges from restaurants, wet markets and foodcourts, animal farming, land

clearing and earthworks, sand mining as well as agricultural and manufacturing activities.

Sources of sewage pollution are effluent from public sewage treatment plants (STP) , effluent

from private STPs, effluent from individual septic tanks, discharge of raw sewage, sewage from

primitive systems and wet markets.

Putrajaya Sewage Treatment Plant (STP 1) is designed to treat an average sewage flow of

22,500 m3 per day. Sewage is characterized in terms of its chemical, physical and biological

composition. The main physical, chemical and biological constituents of domestic sewage

summarized as follows; physical properties such as colour, odor, solids, temperature. Chemical

constituents such as organic (carbohydrates, fats, oil, grease, proteins, and surfactants),

inorganic (pH, chlorides, citrogen, phosphorus, sulphur) and gases (hydrogen sulphide, methane,

oxygen). Developments of sewage treatment systems are mainly concerned with the removal of

suspended and floatable materials, the treatment of biodegradable organic and elimination of

pathogenic organisms.

On the other hand, domestic sewage treatment is designed to produce an effluent low in

solids and organic. Other treatments, which remove the nutrients alter the pH depending on the

receiving environment for the effluent. Two standards (A and B) have been established for the

quality of effluent that discharged from treatment plants to receiving waters. Effluents from

treatment plants are tested in laboratories to ensure that these standards are being met and that

treatment plants are being operated correctly. The pollutants in sewage are measured to better

understand and thus facilitate the treatment of sewage as well as to examine the effects of

effluent or treated sewage on the environment.

Besides that, effluent from all public sewage treatment plants is sampled at regular intervals

to ensure that it meets the required standards. Standard A, should be meet by effluent that is

discharged upstream of a water supply intake, while effluent that is discharged downstream has

to meet Standard B.

Parameters Standard A Standard B

pH value 6.0 – 9.0 5.5 – 9.0

Temperature (oC) 40 40

BOD (mg/L) 20 50

SS (mg/L) 50 100

COD (mg/L) 50 100

Therefore, IWK is now well-positioned to undertake the vital task of ensuring that Malaysians

today and in the future will be able to enjoy a clean and healthy environment through a proper

and well-maintained sewerage system. The field trip allow students to explore their interest in

improving the performance of the sewage treatment plant by learning more about the science and

exploring career options.

Objectives

To understand the behaviour of bio-chemical products in sewage treatment process.

To study and understand the effectiveness of biochemical products in the treatment plant

through :

- Quality of effluent before, during and after application

- Sludge minimisation

- Maintenance efficiency

To ensure the best possible performance of the sewage systems to keep the environment clean as

well as explore new opportunities.

To be highly committed to providing efficient sewage services to all customers towards a

sustainable and friendly environment.

Methodological

On the 18th

of November 2013, Malaysian University of Science and Technology (MUST) had

conducted a field trip to Indah Water Konsortium (IWK) Sdn. Bhd, Putrajaya. Attendees

inclusive of sixteen students from Environmental Biotechnology (BNV 3043) course and headed

by the lectures, Ms. Sherina Binti Kamal, Dr. Tang Sui Yan, Dr. Yan Yi Wei, Miss Yap Pooi

Yan and Miss Akalpita Tendulkar. The list of attendees is available in Appendix A. We arrived

at IWK Putrajaya around 2.30pm. It began with a shorty and informative briefing about IWK

Putrajaya.

Various methods of sewage treatment systems have been developed to protect public health

and the environment. There are two sewage treatment system at IWK, they are individual septic

tank and connected sewage system. Individual septic tank is a settlement tank which only

provides partial treatment of the sewage and waste water that are discharged into it and needs to

be desludged regurlarly. This is mainly to prevent sewage from being released into the

waterways and pollute the environment. While, connected sewerage systems consists of a

network of underground sewer pipes, pump stations, sewage treatment plants and sludge

treatment facilities which operated by gravity. As a result, sewage treatment plants are located at

drainage catchment outlets so that they can capture all the sewage easily without requiring high

cost for pumping.

The starting point where it all started, we went down the steps to ground floor to begin our

tour. The tour began at the sump pump, where we could hear gushing sewage sound come

rushing in from the whole town of Putrajaya. The IWK’s staff explained the processes from the

septic tank to the sewerage plant. We kept looking for gross stuffs and gross smells.

Furthermore, we were told how the sump pump works. We did not get the chance to have a

closer look at the pipes. Sump pump are monitered 24 hours by plant operator. In addition, from

the sump pump, sewage water will be filtered off paper, hairs, bags and others through the screen

chamber before processing the waste. At last, we were told throwing rubbish in the toilet clog up

the system.

After that, domestic waste water pump directed to screen chamber from sump pump. The raw

sewage is distribured between two screen channel for primary and secondary screening. Screen

chamber use conveyor to collects rubbish that people throw in the toilet or drain such as tissue

papers, stocking, pampers and others. Here, we started to feel such a strong bad smell. Next, the

sewage flows through grits channels for further removal of sand and heavy particles. This grit

removal will removes large particles by air lift system and transferred to grit classifier for

separation and storage. Next, we walk in between the yellow lines.

After grit channels, the sewage overflow to aeration tank. In the aeration tanks, organic

material are oxidized by microorganisms into non-harmful material such as carbon dioxide,

water and other inert materials. Microorganisms are suspended with uplift bubbles and the

organic subtances are oxidized to reduce biological oxygen demand (BOD). Besides, oxygen and

air being pumped into the waste to allow the aerobic bacteria to break down the waste.

Clarifier tank are component of secondary clarifier. The treated water is flowed to

clarificaton, where microorganism cells are settled and separated from treated water. The treated

effluent is overflowed through weir plates and discharged to the nearby river. We observed that

the sludge which contain mircroorganism cells settles at the bottom of clarififier, then pump to

sludge to sludge dewatering area where the sludge is flocculated with polymer. Later, it collected

by mechanical scrapper and pumped back to the aerated tank for continuous operation. Sludge

dewatering and drying is an area where the sludge processing takes place. The dewatering sludge

that produced is 12-18 % dried. Thus, the dewatered sludge then further dried for 92% dry solids

by dryer and ready for disposal. Finally, one of the end products are produced, biosolid. It is a

great natural fertilizer.

Finally, we end up our trip around 4.30pm. We were told that if all the processes were

completed properly, there should not be any smell. We found the trip very educational. We learnt

a lot by asking much questions. So, wastewater treatment is not an easy and expensive process.

Conclusion

As a conclusion, the trip to Indah Water Konsortium (IWK) Sdn. Bhd had given us wide

exposure in various methods of sewage treatment systems and its processes. The briefing

conducted by IWK’s staff was educational and beneficial. Waste sludge is an end process of all

aerobic treatment, being it sludge from waste water plant or from drinking water treatment plant.

Proper operation and maintenance including charging and periodical monitoring is required for

sustainable management of decentralised domestic wastewater treatment system. Therefore, the

process flow of sewage treatment plant (STP 1) can be summarized as follow :

Influent Sump pump Screen chamber Grit chamber Aeration

tank Clarifier tank Treated effluent discharged to nearby river.

Influent :

BOD : 250mg/l

SS : 300mg/l

Effluent :

BOD : not more than that 10mg/l

SS : 50mg/l

APPENDIX A

Name of Attendees Matrix No.

1. Susan Silvarajoo

2. Nuramelia Syahirah bt Kushaini

3. Nur Halimah Hamizah binti Hamdan

4. Nick Othman Abdullah

112415012

112415011

B10090051

B12090007

Attachments

Figure 1 show incoming channel of sump pump.

Figure 2 show four inlet pump, where the incoming sewer pumped by four duty into primary and

secondary screen chamber.

Figure 1 Figure 2

Figure 3 and 4 shows four mechanical screen chambers which control by timer to remove

rubbish.

Figure 5 show grit removal to removal sand and heavy particles.

Figure 3 Figure 4

Figure 5

Figure 6 and 7 shows aeration tank which the sewage overflow from the grit channels to the tank

to oxidize organic materials by microorganisms into non-harmful material.

Figure 8 and 9 shows the manual process of sludge using diffuser.

Figure 7 Figure 6

Figure 9 Figure 8

Figure 10 and 11 shows secondary clarifier which is the last process to discharge the clean water

to river.

Figure 12 show sludge dewatering and drying area to process wasted sludge.

Figure 13 show treated water going out of the plant.

Figure 11 Figure 10

Figure 13 Figure 12

Figure 13 show final product as fertilizer.

Figure 14