LCA & drinking water treatment

03/09/2012

1

LCA & drinking water treatment

Desirée Marín CETaqua (Water technology Centre)

XII INTERNATIONAL SUMMER SCHOOL FOR THE ENVIRONMENT

Life Cycle Assessment and Water Issues

04/09/12Universitat de Girona, 3rd-7th September

20121

Contents

1. Introduction

2. Drinking water treatment processes

3. Dealing with LCA and drinking water

4. Conclusions

5. Discussion


2012

03/09/2012

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1. Introduction

Aim: Assure safety in water supply + reduce impacts of water discharge to nature


2012

Avoided impacts vs. Induced impacts?

Outcomes from studies on LCA & drinking water


2012

Energy consumptionmain cause of env.

impacts(Sombekke et.al., 1997; Mahgoub et.al., 2010)

Transport impactsusually insignificant

(Tarantini and Ferri, 2001; Racoviceanu et.al., 2007)

Construction and decommissioning

negligible impacts(Friedrich, 2001; Raluy et.al., 2005;

Stokes and Horvath, 2006)but important when analysing

water transfers( Raluy et.al. 2005, Peters and

Rouse, 2005)

Alternativetreatment

processes havehigher env. burdens

than conventionaltreatments

(Vince et. al. 2008)

Detailed review on the

Summerschool’s book !

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2. Drinking water treatment processes

Objective of a DWTP:

Reduce or eliminate

undesired components in water (e.g particulate matter, oils and fats, toxic chemicals, viruses, pathogen agents, bacteria, etc.)


2012

Drinking water regulations

98/83/EC Stablishes thelegal quality requirementsof water for humanconsumption including:

• Microbiological

• Chemical

• Other parameters


2012

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98/83/EC


2012

Mandatory compliance

98/83/EC


2012

Mandatory compliance

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98/83/EC


2012

To be controlled

Drinking water regulations


2012

75/440/CEE Defines 3 types of surface water intended for drinking water abstraction in terms of quality/treatment needed:

• Type A1: simple physical + disinfection

• Type A2: normal physical + chemical + disinfection

• Type A3: intensive physical + chemical + extendedtreatment + disinfection

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Treatment processes

• Physical treatment

� Clarification

� Filtration

� Membrane treatments

• Chemical Treatment

• Disinfection

• Other treatments


2012

Extraction

Pre-treatment

Treatment

Advanced treatment

Post-treatment

Disinfection

Clarification

Objective: Eliminate

particulate matter

(diluted compounds mainly organic matter from nature)

Particulate

matter colours

water

Main processes:

� Coagulation

� Flocculation

� Decantation

� Flotation


2012

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Clarification: Coagulation-flocculation


2012

Coagulants: salts based on Al or Fe (Al3SO4, FeCl3, …) or acid/basic polymers aluminum based (PAC, Wac, Alba 18, etc.)

Flocculants: inorganics (activated silica, clays, sand or calcite) or organics (starch, alginates or polyacrylamides polyDADMAC)

Clarification: Decantation


2012

Rectangular static vertical clarifier

lamellas

�Static/Dynamic

�Rectangular/Circular

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Clarification: Decantation


2012

Circular dynamic sludge recirculation clarifier (Accelator®)

� Dynamic: sludge recirculation/ sludge blanket

Clarification: flotation

Dissolved/induced air flotation eliminates light flocs (algae, oils, etc.)


2012

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Filtration

Objective: Remove

particulate matter that cannot be sedimentated by its retention in a bed

of a porous material or in a fixed support

� Structure: Open/closed

� vfiltration: low /high

� Material:

� Sand

� Activated Carbon

� Dual-media (multi- layer)

� Anthracite, etc.


2012

Membrane treatments


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Membrane treatments

Microfiltration Ultrafiltration


2012

� Submergible

� Pressurised

(in-out/ out-in)

Nanofiltration

Membrane treatmentsReverse Osmosis


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Membrane treatments

Electrodialysis reversal

Removes ions and other charged species by using electricity


2012

Chemical treatment

Acidification

Reduces pH by dosing CO2

in order to remineralise water from membranes

or stripping

Stripping

Eliminates dissolved gases (H2S, CO2, etc.) and VOC’s by an aeration (G-L exchange) �


2012

Stripping /CO2 towers

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Chemical treatment

Softening

Reduce carbonate in remineralised water by:

� Lime addition

� Catallytic process

� Clarification

� Ion exchange resins


2012

Neutralisation

Post-treatment based on a remineralisation (pH adjustment) by dosing calcite (calcium carbonate), calcium hydroxide, etc. �

Other: Adsorption

Objective: eliminate pesticides, detergents, chlorinated solvents, phenols, PACs, odours, colour, etc.

Regeneration of AC needed!


2012

GAC

bed filter

Activated Carbons:

� Powdered (PAC)

� Granular (GAC)

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Disinfection

Objective: Remove dissolved

mineral matter, eliminate pathogen agents, eliminate taste and odours, ammonia, etc. by an oxidation process

This is a key step!

Not disinfected =

Main types:

� UV radiation

� Ozonation

� Chlorine andderivatives

� Potassiumpermanganate

� Electro-chlorination


2012

Disinfection


2012

UV disinfection lamps Ozone (produced in-situ)

� Oxidation efficiency: O3>ClO2>HClO>OCl->NH2Cl� Permanence: NH2Cl (days) > ….> O3 (30 min)

Potassium permanganate

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3. Dealing with LCA in drinking water

ISO 14040 & 14044 (2006)

Clearly identify in a report important decisions made along the LCA stages

ILCD Handbook http://lct.jrc.ec.europa.eu/assessment/publications


2012

Goal

Definition of:

� Aim of study

� Limitations

� Target Audience

� Intended application

� Decision context


2012

LCA Direct applications

(from ISO 14040/44)

• Product development and improvement

• Strategic planning

• Public policy making

• Marketing

• Other

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Goal: Aim of study

State and keep in mind:

� Main reasons for the study

� Commissioners

Study results and report shouldprovide satisfactory answers to commissioner’s objective


2012

Goal: Limitations

Identify limitations on the usability of the LCA resultsdue to the goal or methodology:

� Limited impact-coverage

� Assumptions made

� Method-related


2012

Limited impact-coverage Method-relatedAssumptions made on

the system or scenarios

Carbon

footprinting

Primary energy

consumption

LCIA method:

Site-specific

results

LCI method approach:

market-price allocation in eco-efficiency studies

Representativeness:

time, location, use-

pattern, etc.

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Goal: Target audience

Identify to whom the results will be communicated

� Critical review needs

� Form and technical level of the report


2012

Citizens

Local/

regional

authorities

National/

international

authorities

Water utilitiesScientific

community

Know env. impacts of a DWTP in the

neighborhood

Supportdecision-

making on aninvestmenton a DWTP

Support policy-making on a

chemical used forwater purification

Improve eco-efficiency of a

plant, help decision-makingon a technology

Compare results or take them as

a basis for other studies

Examples of potential target audience in LCA-drinking water studies and intended applications

Goal: Intended applications

Identification of Key Environmental Performance Indicators

(KEPI) of a product group for Ecodesign / Simplified LCA

Weak point analysis of a specific product

Detailed Ecodesign / Design for recycling

Perform simplified KEPI-type LCA / Ecodesign study

Comparison of specific goods and services

Benchmarking of specific products against the product group’s

average

Green Public or Private Procurement (GPP)

Development of life cycle based Type I Ecolabel criteria

Development of Product Category Rules (PCR) or a similar

specific guide for a product group

Development of a life cycle based Type III environmental

declaration for a specific good or service

Development of the “Carbon footprint”, “Primary energy

consumption” or similar indicator for a specific product

Greening the supply chain

Clean Development Mechanism (CDM) and Joint

Implementation


2012

Providing quantitative life cycle data as annex to an Environmental

Technology Verification (ETV) for comparative use

Policy development: Forecasting and analysis of the

environmental impact of pervasive technologies, raw material

strategies, etc. and related policy development

Policy information: basket-of-products (or product groups) type of

studies

Policy information: identifying product groups with the largest

environmental impact

Policy information: identifying product groups with the largest

environmental improvement potential

Monitoring environmental impacts of a nation, industry sector,

product group, or product

Corporate or site environmental reporting including calculation of

indirect effects in Environmental Management Systems (EMS)

Accounting studies that according to their goal definition do not

include any interaction with other systems

Development of specific, average or generic unit process or LCI

results data sets for use in specified types of LCA applications

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Goal: Decision context


2012

LCI Modelling framework:

Attributional or consequential

Goal: Attributional LCA


2012

PROCESS DATA

LCA- IMPACTS ACCOUNTING

ENVIRONMENTAL

PROFILE

HOT-SPOTS IDENTIFICATION

PROCESS IMPROVEMENT

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Goal: Consequential LCA


2012

≠ POSSIBLE SCENARIOS

PROCESS

LCA MODEL

≠ ENVIRONMENTAL

CONSEQUENCES

SCENARIOS COMPARISON

STRATEGIC PLANNING

POLICY and DECISION-MAKING

Goal: Example

�Project: (CEN-2008-1027)

�Task: Carbon footprint of drinking water treatment processes

�Commissioner: Agbar with funding of CDTI (Spanish Ministry)

�Aim: Compare different drinking treatment processes in terms of CO2 equivalent emissions

�Audience: water utility (Agbar) + CDTI + scientific community


2012

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Goal: Example

�Intended applications:

� Comparison of specific goods and services

� Development of the “Carbon footprint”, “Primary energy consumption” or similar indicator for a specific product

�Decision context: Situation C: accounting

�LCI modelling framework: Attributional LCA

�Limitations: inventory focused on carbon footprint


2012

Goal: Example

Attributional LCA


2012

3.2 M inhabitants

250 hm3/year

3 river basins(surface and groundwater) and seawater

High water stress and industrial activity

6 waterworks

12 treatmenttechnologies

Barcelona MetropolitanArea, Spain

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Goal: Example

Attributional LCA

Environmental assessment of all the treatment facilities in the BMA at a process-unit level and focused on carbon footprint


2012

Pre

-tre

atm

en

t

Pre

-tre

atm

en

t

Goal: Example

Consequential LCA


2012

BMA Drinking water tre

atment

carbon footprint (T

n CO2 eq)

Scenario analysis

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Scope

Definition of:

� System’s description

� System’s function

� Functional unit / Reference flow

� Boundaries

� Cut-off criteria

� Impact categories to be covered


2012

Scope: System’s description

Knowing the system is important to:

� Define properly the functional unit

� Interpret results correctly and re-adjust LCI/LCIA if needed


2012

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Scope: Functional unit


2012

Example of functional unit: 1 m3 produced waterwith legal minimum quality requirements forhuman consumption according to 98/83/ECEuropean Directive

System’sfunction?

E.g. To produce drinkingdrinking water

According to:

� Goal & scope

� Comparisons to be madebetween system’s

Recommendation: look at previoussimilar studies

Scope: Boundary and cut-off criteria example


2012

� Cut-off criteriabased on literature

� Boundary: cradle to gate

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Scope: Impact categories and method req.


2012

� Method selection:

e.g. CML 2 baseline

LCA Aim?Quantify GHG

emissions

�Identification of impact categories:

Climate change (kg CO2 eq.)

Calculationmethod

requirements?

Midpointmethod withCC category

IPCC ,Time horizon

100 years

LCI: Data sources


2012

Drinking watertreatment plant

Energy consumption

Chemicals consumption

Generated waste

Etc.

Databases(i.e Encoinvent )

Production of 1kwh of Electricity in Spain

Production of 1 kg of NaOH

Disposal of 1 kg of inert waste to landfill

Etc.

Literature Production of 1 kg of Granular Activated Carbon

(Muñoz 2006, Bayer et.al. 2005)

Activation of 1 kg of Granular Activated Carbon

(Muñoz 2006, Bayer et.al. 2005)

Own developed Production of 1 kg of aluminium polychloride

Production of 1 kg of antiscalant

Production of 1 kg polyDADMAC

Production of 1 kg polyacrylamide

EXAMPLESDATA SOURCE

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LCI: Data from DWTP

Types:

� Construction

� Operational data� Financial data (for further analysis such as LCC)

Sources:

� Water utility

� Local/regional authorities

Steps:

� Identification of data needed

� Design of a data collectionform

� Know data quality andcollection procedure

� Assess data apropiateness

� Identify data gaps


2012

LCI: Example of data form


2012

Comments: � Transport data is missing

but many suppliers arespecified

� Only sludge as a waste is specified (sand, GAC, etc. missing) and transport is missing

� Sludge treatmentchemicals are not linked to a specific treatmentprocess

2006 2007 2008 2009 2010

kg XXXXXX XXXXXX XXXXXX XXXXXX

kg XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX

kg XXXX XXXXX XXXXXX XXXXXX

kg XXXXXX XXXXXX XXXXX XXXXXX

kg




kg XXXXXX

kg XXXXXX


kg XXXXX XXXXXX XXXXXX XXXXXX XXXXXX

kg XXXXXX XXXXXX

kg XXXXXX XXXXX

kg XXXXXX XXXXX

kg XXXXXX XXXXXX

kg XXXXXX XXXXXX

kg XXXX XXX XXX XXXXX


kg XXXX XXXXX XXXX XXXXX XXXX

kg XXXX XXXX XXXX XXXX


kg XXXXXX XXXXXX XXXXXX XXXXXX XXXXX

kg XXXXXX XXXXXX XXXXXX XXXXXX XXXXXkg XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX

NEW kg XXXXXX XXXXX

REGENERATED kg XXXXXX XXXXXX XXXXXX

NEW kg XXXXXX XXXXX

REGENERATED kg XXXXX XXXXXX XXXXXX XXXXXX XXXXXX

kg XXXXX

GAS / KG SPRAY

DRYIED m3 XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX

GAS / KG REGEN. m3 XXXXXX

kWh XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX




kWh XXXXXX XXXXXX


kWh XXXXXXkWh XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX



m3 XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX




m3 XXXXXX XXXXXX

% XXXXXX XXXXXX

Surface

Reverse Osmosis

Ozonation

Pumping (water elevation)

Water extraction (surface and groundwater)

Pre-treatment (Pre-oxidation, Decantation & Sand-

% of total produced water coming from RO

Osmotised water (produced)

Groundwater

Surface

Groundwater

GAC NORIT

GAC CHEMV.

GAC regenerated on-site

GAC REGENERATION on-

SPRAY DRYING

Spray drying

Thickening

Sludge pumpingGAC reactivation on-site

Produced water pumping to storage tanks

PAX

ALBA - 18

PAX - XL60

PAX - 18

SPRAY DRYIED TO CIMENT KILNS SPRAY DRYIED TO LANDFILL

DEWATERED TO LANDFILL

SULPHURIC ACID

ANTISCALANT

IRON CHLORIDE (FeCl3)

SODIUM BISULFITE

NITROGEN OZONE

OXYGEN OZONE

DEFLOCULANT (NaOH)

PROSEDIM ASP-34

POLYELECTROLITE OPTIFLOC A -

CHLORINE CARBUROS METÁLICOS

CHLORINE KEMIRA

CALCITE

CHLORINE KEMIRA

CHLORINE CARBUROS METÁLICOS

SODIUM CHLORITE ARAGONESAS

SODIUM CHLORITE ATOFINA (L)

ALUMINA

ALUMINA H40

Wa

ter

Water intake

Produced water

Osmotised

water

En

erg

y

Natural Gas

Wa

ste

Sludge disposed

Ma

teri

als

Activated

carbon

Electricity

(Water

treatment)

Electricity

(Sludge

treatment)

Drinking Water Treatment plant X

Ch

em

ica

ls

Water

treaatment

Pre-oxidation

Coagulation-

Decantation

Ozonation

Reverse

Osmosis

Disinfection

Sludge

treatment

Sludge

treatment

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LCI: Example of data formTreatment process Flow 2007 2009 Unit Description / Assumptions

Extraction

Electricity xxxxxxx xxxxx kWh Groundwater extraction pumps

Waterxxxxx xxxxxxxx m3 Surface water

xxxxxxx xxxx m3 Groundwater

Pre-treatment

Electricity xxxxxx xxxxxxxx kWh

Chlorinexx xxxxx kg Distance to supplier 170 Kmxx kg Distance to supplier 15 Km

Sodium chloritex kg Distance to supplier 350 Km

xx kg Distance to supplier 650 KmAluminum polichloride x xxx kg Distance to supplier 170 KmAluminum sulphate xxx Kg Distance to supplier 170 Km

Sand waste xx xx kg Distance to landfill 45 km

Pumping (elevation) Electricity xxxxxx xxxxxx kWh

Ozonation

Electricity xxxxxxx xxxxxxx kWh Ozone in-situ production Oxygen xxxx xxxx kg Distance to supplier 25 KmNitrogen xxxx xxxx kg Distance to supplier 25 Km

GAC filtration

GAC newxxxxx kg Distance to supplier 1300 Km

xx kg Distance to supplier 1300 Km

GAC regeneratedxxx kg Distance to supplier 1300 Km

xxxxx Kg Distance to supplier 1300 Km

Reverse Osmosis

Electricity xxxxxxxx kWhOsmotised water xxxxxxx m3

Sulphuric acid xxx KgIron Chloride xx kg CoagulantSodium bisulfite x kgAntiscalant x kg RO Pre-treatmentCalcite xxxx kg Remineralisation

Post-treatmentChlorine

xxxx xxxx kg Distance to supplier 170 Kmxxx xxx kg Distance to supplier 15 Km

Water xxxxxxxx xxxxxxx m3 Produced at plant


2012

LCI: DatabasesLink DWTP data to DB’s process datasets:


2012

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LCI: Databases


2012

Flow/Process Database LCI Process dataset

Electricity Ecoinvent 2.0 Electricity, low voltage, at grid/ES S

Chlorine Ecoinvent 2.0 Chlorine, liquid, production mix, at plant/RER S

Chlorine Transport Ecoinvent 2.0 Transport, lorry 3.5-7.5t, EURO3/RER S

Sodium chlorite Ecoinvent 2.0 Chlorine dioxide, at plant/RER S

Coagulant transport Ecoinvent 2.0 Transport, van <3.5t/RER S

Coagulants/flocculants x Own inventory data set

Sand to landfill Ecoinvent 2.0Process-specific burdens, inert material landfill/CH S

Oxygen Ecoinvent 2.0 Oxygen, liquid, at plant/RER S

Nitrogen Ecoinvent 2.0 Nitrogen, liquid, at plant/RER S

Reactivated GAC x Adapted from: (Muñoz, 2006)

GAC production x Adapted from: (Muñoz, 2006)

Sodium Bisulfite Ecoinvent 2.0 Sulphite, at plant/RER S

Sulphuric acid Ecoinvent 2.0 Sulphuric acid, liquid, at plant/RER S

Calcite Ecoinvent 2.0 Limestone, milled, packed, at plant/CH S

Hydrochloric acid Ecoinvent 2.0 Hydrochloric acid, 30% in H2O, at plant/RER S

Iron chloride (III) Ecoinvent 2.0 Iron (III) chloride, 40% in H2O, at plant/CH S

Natural gas Ecoinvent 2.0Natural gas, burned in industrial furnace >100kW/RER S

Sodium hydroxide Ecoinvent 2.0Sodium hydroxide, 50% in H2O, production mix, at plant/RER S

Not found in DB butassumption ismade bysubstitution

Literature

LCI: LiteratureProduction of Granular activated Carbon from «I. Muñoz, PhD. Thesis UAB 2006» :


2012

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LCI: Own developedExample: Anionic copolymer (flocculant)*:


2012

Info from:

� Supplier’s

� Literature**

� Calculations (mainly stoichiometric and thermodynamic)

Not in DB’s nor

in literature

Sodium hydroxide,

50% in H2O,

production mix, at

plant/RER S

(ECOINVENT)

Acrylic acid, at

plant/RER S

(ECOINVENT)

Water,

deionised, at

plant/CH S

(ECOINVENT)

Acrylonitrile E

(Industry data

2.0 )

*All rights reserved. No part of this information may be used, reproduced or transmitted in any form or by anymeans without previous permission of the authors .

**Chemical Engineer's Handbook - Robert H. PerryEncyclopedia of Industrial Chemistry- ULLMANN’S

LCIA


2012

Classification

Midpointimpacts

calculation

Endpointsimpacts

calculations Normalisation Weighting

METHOD

Inventory

• Compound 1

• Compound 2

• …

• Compound n-1

• Compound n

Impact categories

•• ClimateClimate changechange• Ozone layer dep.

• Acidification

• Human toxicity

• Photochemicaloxidation

• …

Damage categories

• Human health

• Ecosystems

• Resources

• …

Normalisationfactors

• Default values • Regional factors•…

Weighting factors

• Default values

• 1 for all impacts

• Own criteria

• Etc.

� SimaPro 7.2 Software � CML 2 baseline

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LCIA: impact categories

Impact categories most important in DWTP’s:

� Climate change

� Ozone layer depletion

� Human toxicity

� Water use


2012

LCIA: method-attached limitations

Human toxicity

Impacts on human health due to waterconsumption cannot be estimated through LCA � Riskassessment

Water use

Further research is needed in order to ‘know’ theregionalised impacts of fresh-water use (consumptiveand degradative)


2012

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Interpretation of results

�Identification of significant issues :

LCI weak point analysis

Key impact categories

�Scenario analysis

�Sensivity and uncertainity analysis


2012

Int. of results: examples


2012

Pre-treatment, pumping and EDR are the process-units with higher environmental impacts.

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�energy consumption is the main source of impacts on climate change

�chemicals consumption (e.g. coagulants, oxidants) is the principle cause of impacts on the ozone layer depletion


2012


�Plants with membrane treatments have higher GHG emissions related to energy consumption

�Transport presents high GHG emissions in the conventional plants assessed mainly due to GAC transport outside Spain.


2012

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�Conventional plants: pre-treatment has high GHG emissions due to chemicals consumption.

�Membrane treatment: pre-treatment is not significant but high GHG emissions associated to the electricity consumption.

EDR: 0.40 kg CO2 eq./produced m3

RO (Brackish): 0.52 kg CO2 eq./produced m3

RO (seawater): 1.67 kg CO2 eq./produced m3


2012

Car

bo

nfo

otp

rin

t


During drought (2007) the plant prioritised groundwater extraction:

-High extraction impacts due to pumping

-Low chemicals and energy consumption in pre-treatment and GAC filtration

The impacts of adding a new

process (UF+RO) to meet new THM regulations increased 0.04 kg CO2/m3 the plant’s carbon footprint. However, it also improved its water quality.


2012

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�Sludge treatment presented lower impacts (20%) than water treatment (80%).

�Recycling in cement industry can reduce the environmental impact of cement

production and avoid the impacts from sludge landfilling. However, additional

sludge treatment (e.g. drying), may be required.

�Need to use consequential LCA to decide whether to treat sludge previous to its valorisation or not, depending on the amount of sludge and its requirements .


2012



2012

5 MW installed7 GWh/year produced

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33


�GAC is produced and reactivated in Italy or The Netherlands (1300 km from Barcelona)

�Impact reductions up to 18% should have been achieved in the BMA if there was a GAC generation and reactivation plant in Spain.

�There are > 260 drinking water treatment plants using GAC in Spain


2012

9% impactreduction

18% impactreduction

-2.000 4.000 6.000 8.000

10.000 12.000 14.000 16.000 18.000

BMA Savings (average 2007, 2009)

Tn C

O2

eq

./ye

ar

GHG's emissions savings

Plant located in Madrid (Spain)

Plant located in Catalonia (Spain)


�NaClO2 causes around 30% of the chemicals’ impacts.

�The substitution of NaClO2 by Cl2 in conventional plants:

75% the disinfection carbon footprint

5% the plant’s carbon footprint

40% the disinfection impacts on ozone layer depletion

90% the plant’s impacts on ozone

layer depletion.


2012

3%

4%

5%

5%

HCl; 11%

NaClO2; 28%

PAC; 44%

Carbon footprint of chemicals- conventional

plants

PolyDADMAC

Lime

Others

CO2

HCl

NaClO2

PAC

03/09/2012

34



2012

�Carbon footprint of a drinking water treatment plant: 0.1 - 2.2 kg CO2 eq. /m3

�The carbon footprint of the water treatment in the BMA is around 0.4 kg CO2

eq. /m3


Sensivity analysis: how results change when...?


2012

Own inventory for polyelectrolyte

Iron Chloride inventory for polyelectrolyte%

Ozo

ne

laye

r d

eple

tio

n

% C

limat

e C

han

ge

03/09/2012

35

Conclusions

� Centralised or decentralised solutions for environmentalproblems? � Need for a holistic approach (LCA)

� The impact of a DWTP depends on inlet water quality andon its location and design (Carbon Footprint 0.1-2.7 kg CO2/m3)

� Membrane technologies have higher GHG emissions but also produce higher quality water (EDR 0.4 ; RO (Brackish) 0.52; SWRO 1.67 kg CO2 eq./m3) � Include water quality

parameters in order to also quantify the environmental benefits of water treatments

� Need of specific research on inventories of chemicals,

materials and waste disposal in the water sector


2012

Documents

LCA & drinking water treatment