Environmental and Social Life Cycle Assessment - Climate Change

Environmental and Social Life Cycle Assessment

Leonor Patricia Güereca, Adba Musharrafie, Edgar Martínez, Flor Hernández, Alejandro Padilla, Liliana Romero, Margarita Cisneros-Ortiz, J. M. Morgan-Sagastume, Adalberto Noyola.

XIV IWRA World Water Congress. Porto de Galinhas Pernambuco Brazil. September 25-

29, 2011.

Content

• Introduction

• Life Cycle Assessment (LCA) Inventory for five WWTP

• Life Cycle Assessment of two inflow scales of wastewater treatment

• Social Life Cycle Assessment

• Conclussions


29, 2011.

Introduction

In Latin America and the Caribbean:

• There is a common belief that : any kind of technology used will avoid environmental pollution

• New wastewater treatment plants must been installed

• Life Cycle Assessment (LCA) analysis the environmental impacts from an holistic approach

• In this project, the Life Cycle Assessment approach is applied to evaluate the environmental and social impacts of wastewater treatment systems


29, 2011.

Background

LCA studies the environmental impacts through the complete life

cycle of a product, process or service; from the raw materials extraction to the final disposal;

considering all the affected vectors (air, water, soil) and a broad time

framework.

Introduction


29, 2011.

Life Cycle Assessment Structure

Interpretation

Goal definition and scope

Inventory analysis

Impact assessment

Pre-treatment Primary

treatment

Secundary

treatment

Sludges

Wastewater

Wastewater

treatedInput

Solid waste management

Production of chemicals raw

material

Transport of chemicals raw

material

Deodori

zation

Electricity

generation

Fuels generation

Water useEmissions

Discharges

Wastes

Raw material extraction, manufacturingand transport of equipment

Emissions Discharges Wastes

Electricity

generation

Electricity

generation

INVENTORY

Introduction

• Acidification

• Eutrophication

• Photo-oxidants

formation

• Climate Change

• Aquatic toxicity

Introduction

Impact Categories

0

0.2

0.4

0.6

0.8

1

Lodos Activados Laguna de estabilización

Photo-oxidants formationt eq etileno

0

500

1000

1500

2000

2500

3000

3500


Greenhouse Gases Emissionst eq CO2 (100 años)

0

2

4

6

8

10

12

14

16


Acidification t H+

0

50

100

150

200

250


Aquatic toxicity eq 1,4-DCB

Life Cycle Inventory for five WWTP


Methodology

System Abbreviation Caudal

(l/s)

Activated sludge (small) AS-S 18

Stabilization ponds (small)

SP-S 12

Activated sludge (big) AS-B 1437

Primary treatment (big) PT-B 1344

Representative scenario activated sludge (small)

RSAS-S 13

The Life Cycle Inventory presented corresponds to the analysis of specific data obtained from four real wastewater treatment plants and one representative scenario of

wastewater treatment for Latin-America and Caribbean.

Equipment

manufacturin

g

Equipment

transportation

Influent

Civil works

Operation

Effluent

Wastewater Treatment Plants description Processes considered in the LCI


Results and discussions

Description

Units per m3 of

wastewater

treated during 20

years AS-S SP-S AS-B PT-B RSAS-S Construction

Concrete g 36 140 23 0.69 *

Equipment fabrication Steel g 1.26 0.68 0.33 0.04 *

Operation Electricity kJ 4915 0.33 3550 200 2316

Chloro

(hypochlorite) g 18 NO 3.62 NO

36

86

Lime (CaO) g NO 2.11 NO NO NO

Ferric chloride g NO NO NO NA NO

* In process, NO=not applicable

Energy and raw materials used in each WWTP, related to m3 of wastewater treated during 20 years.


29, 2011.

Life Cycle Inventory Results and discussion

The stabilization pond (SP-S) and the activated sludge (AS-S) are the systems with highest BOD5 removed

System Flux BOD5 (g/m3) BOD5 removed

(g/m3) Removal

Efficiency (%)

AS-S Influent 262.2

259 99 Effluent 3.17

SP-S Influent 380

266 70 Effluent 114

AS-B Influent 103

98 96 Effluent 4.6

PT-B Influent 267.4

150 56 Effluent 117.7

RSAS-S Influent 244

214 88 Effluent 30


29, 2011.

Life Cycle Inventory

• Preliminary results of the Life Cycle Inventory

– The stabilization pond studied, used more raw materials than the other systems analyzed in the construction stage

– Operation is the stage with most electricity requirements

– The stabilization pond analyzed is the system with the highest quantity of BOD5 removed, the lowest electricity consumption and the only system with methane emissions

– Activated sludge systems present the highest removal efficiencies and the highest electricity consume


29, 2011.

Life Cycle Assessment of two inflow scales of

wastewater treatment

LCA of two inflow scales of wastewater treatment

Methodology

Two scenarios of wastewater treatment are analyzed according to their scales of operation:

Equipment

manufacturin

g

Equipment

transportation

Influent

Civil works

Operation

Effluent

Scope of the LCA Processes considered in the LCA

Small WWTP Big WWTP

Single Inflow 12 l/s 1437 l/s

Quantity 120 plants 1 plant

Lifetime 20 years 20 years

Total inflow during lifetime

7,568,640 m3 X

120

906,344,640 m3

FUNCTIONAL UNIT = 906,344,640 m3 .

Methodology

• Construction

• Equipment fabrication and transport

• Operation

• Direct and indirect air emissions

• Landfill leachates

• Chemicals

• Fuel extraction

• Physicochemical parameters of wastewater and treated water

In order to facilitate the comparability, the water quality of the influent and effluent were taken from the Big WWTP for both

scenarios


29, 2011.

Abreviation Impact category

AC Acidification

AT Aquatic toxicity

AD Abiotic depletion

EU Eutrophication

GW Global warming

HT Human toxicity

PF Photo-oxidants formation

TT Terrestrial toxicity

LCA for two inflow scales of WW treatment

Results and discussions

•The Life Cycle Impact Assessment (LCIA) was developed using the CML2000 methodologies and the software TEAM 4.0.

•The relative performance of Big WWTP is better than Small WWTP for all the impact categories analyzed. The difference is more than 100% in almost all categories.

•Aquatic toxicity (AT) and eutrophication (EU) present similar impacts because in the operation stage, the same water quality is considered for both scenarios.

0

50

100

150

200

250

300

AC AT AD EU GW HT PF TT

Rela

tive

per

form

ance

(%

)

Impact Categories

Big WWTP

Small WWTP


29, 2011.


• The scenario of several small WWTP generates higher impacts for all the impact categories analyzed, but in eutrophication and aquatic toxicity, the impacts are almost equivalents.

• Operation is the stage with most environmental impact due to the secondary treatment in which the aeration systems demand more electricity.

• The results suggest that the installation of one big WWTP is better, in environmental terms that several small WWTP for all the impact categories analyzed. However, in order to extrapolate the results obtained to other locations, special attention should be taken to wastewater transport, electricity mix and sludge management.


29, 2011.

Preliminary Conclusions


Social Life Cycle Assessment

Backgroung Sustainability = Economic + Environmental+ Social



29, 2011.


Methodology:

• Guidelines for S-LCA for products and services (UNEP, 2009) Social Impact Categories:

• Workers

• Local comunity

• Society (National / global)

• Customers

• Value chain


29, 2011.

Instalation

Wastewater treatment

Final disposition

Equipment fabrication

Transport

Construction

Workers Comunity Society Customers Value chain

CATEGORIAS DE IMPACTO =

• Work hours • Income • Forced work • Equity • Health and security • Capacitation

• Local employment • Contribution to education

• Development of society • Contribution to technological development

• Responsability with customers

• Capacitation and reinforcement of the value chain



Preliminary results

Aerobio52%

Anaerobio4%

Mixto44%

Tipo de tratamiento

Mecanizadas68%

No mecanizadas

32%

Tipo de PTAR

Si92%

No8%

Seguridad social

Basico21%

Educacion Media

26%

Basico y media11%

Educacion media y profesionistas

42%

Nivel de estudios

25 WWTP visited in Mexico, Chile, Domican Republic, Colombia and Guatemala.


Preliminary results

Buena63%

Mala5%

Sin importancia

32%

Imagen de la comunidad de la PTAR

% de hombres trabajando

89%

% de mujeres trabajando

11%

Relacion hombres vs mujeres

1 a 1064%

11 a 2012%

20 a 508%

> 5016%

No. de trabajadores

Municipal50%

Estatal14%

Federal9%

Concesion privada

27%

Operacion de las PTAR

Life Cycle Inventory Conclussions

• According to preliminary Social Life Cycle Assessment in 25 WWPT of Latinamerica and the Caribbean region::

– The workers in the WWTP are principally men, with elementary and high

school education and they has social security

– Only a minority of the WWTP has a bad image with the community, which is due principally to the odor emissions

– The WWTP has between 1 to 10 workers, which is in concordance with the treated flux


29, 2011.

Recommendations

• It is necessary to obtain precise information about:

– chemical raw material used during operation stage – physic-chemical and biological parameters of the influent

and effluent for all the analyzed systems – to estimates the nitrous oxide emissions for all the analyzed

systems

• It is imperative to broad the sample of WWTP and their communities and strength the analysis in order improve the quality of the social life cycle assessment


29, 2011.

Acknowledgements

International Development Research Center (IDRC) for supporting this research.

Thank you!

Patricia Güereca

[email protected]


29, 2011.

Environmental and Social Life Cycle Assessment - Climate Change

Documents

Transcript of Environmental and Social Life Cycle Assessment - Climate Change