Micropollutants in the aquatic environment:The Swiss strategy

Adriano Joss, Hansruedi Siegrist (eawag),

Michael Schärer, Christian Abegglen (Bafu, VSA)

Hilversum, 21 November 2013

Overview

The Swiss strategy

The Technologies• Powdered activated carbon• Ozone

Costs and Energy

slide 2

Prioritization of sources and pathways

Agriculture

traffic

Atmospheric deposition

Waste water treatment plants

Urban water management (storm flow)

Land fillsOther activities (shipping, leisure, ..)

Agriculture

slide 3

Analysis of situation in Switzerland -Regional problems with micropollutants

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Regional problems with micropollutants

• Wastewater load in (surface) waters related to population density• WWTP are a major source

Anteil gereinigtes Abwasser in grossen und mittleren FliessgewässernPercentageof treated waste water in Swiss streams

Population density

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Development of an assessment concept

see Götz et al. 2010, Kase et al. (2011)

see http://www.bafu.admin.ch

slide 6

Evaluation of measures

see http://www.bafu.admin.ch

measure effectiveness

Primary measuresInformation Depends on substance (group),

only applicable for limited amount of substances

Regulation of production and application of substances

applicable for limited amount of substances

Ban of substances applicable for limited amount of substances

Source separationMeasures at primary pollution sources (production plants)

applicable for limited amount of substances

Complete change of urban waste water management (urine separation etc.)

Very high costs, only applicable on the long term (> 50 y)

End of pipe measuresComplementary treatment (z. B. ozone, active carbon)

Reduction of a broad range ofpollutants

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Source control measures have highest priority:- Registration and regulation of products- Green chemistry- Behavior of consumers – information of public- Use and disposal of substances

But:- “long-term options”- Thousands of substances can hardly be regulated- Replacement of some substances is very difficult (pharmaceuticals) or impossible (natural estrogens).

Possible measures

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Adaptation of water protection ordinanceResults of consultation 2009-2010

1. Problem and need for measures supported

Over 80 % of the statements support a goal-oriented extension of municipal WWTPs

2. Need for adaptation:

• Financing: Need for a nationwide funding based on the polluter-pays-principle

• More experience with technical processes necessary

• National coordination of planning

Several interventions in federal assemblyfor example discussion in the Committees for the Environment, Spatial Planning and Energy CESPE of the council of states

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parliamentary interventionof the Committee for the Environment, Spatial Planning and Energy (CESPE ) of the council of states

Development of financing solution in agreement with the “polluter pays principle”

Establishment of legal requirements for financing and implementation of measures

Accepted by federal council and council of states

Accepted by national council on March 15 2011

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WWTPs today represent relevant point sources of MP

Heavily loaded receiving waters mainly in high populated areas (low dilution)

Advanced treatment foreseen in 100 out of 750 WWTPs (provisional):

• big WWTPs (load reduction; ≥ 100’000 pe)

• sensitive waters

• waters serving as drinking water resources (precautionary principle)

Treatment aim (provisional): 80% removal of representative compounds

benzotriazole, carbamazepine, diclofenac, mecoprop and sulfamethoxazole

No technology prescribed; current focus: ozonation and PAC

Swiss ordinance on micropollutants

• Investment costs: 1.2 bn CHF (= 1 bn €)• Increase of total annual costs: 130 m CHF per year

= 6 % of actual costs of wastewater disposal in Switzerland

• Adaptation of federal water act: Financing 75 % of investment costsslide 11

Energy consumption and costs

Electricity

Per WWTP 10 – 30 % increase National increase: 0.1 % of national electricity consumption

<0.1 % of national primary energy consumption

Costs

Per WWTP 5 – 35 % increase National increase: 12 % of annual costs of wastewater treatment

6 % of annual costs of wastewater disposal

See www.bafu.admin.ch/micropoll (or www.micropoll.ch)

Ongoing work• Collaboration with stakeholders

• Adoption of Swiss Water protection act in progress• Spring 2013 – submission to

council of states• Public consultation ended by

end of august 2012

• Further development based on• Statements during public

consultation of water protection ordinance

• Parlamentary intervention of CESPE

Financing solutionWorking group• Federal Office for the Environment (lead)• Cantons• Operators/Owners of WWTPs

Strategic board• Federal Office for the Environment (lead)• Cantons• Operators/Owners of WWTPs• Swiss water association• Research• Industry

Planning of measuresWorking group• Federal Office for the Environment (lead)• Cantons• Operators/Owners of WWTPs

Processes for waste water treatmentWorking group within Swiss Water Association

slide 13

Ongoing work

financing solution (adaptation of water protection act)

Earmarked financing solution based on polluter pays principle (limited in time)

Planning of measuresPlanning on a watershed level

proportionality

Experience with technical processes (waste water treatment)Working group within Swiss water assiciation (VSA)National and international build up of expertise International collaboration (NL, D-BW, D-NRW, ……..)

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Overview

The Swiss strategy

The Technologies• Powdered activated carbon• Ozone

Costs and Energy

slide 15

Requirements for advanced treatment

Broadband removal: effective on a broad mixture of organic compounds

Transformation products: the formation of toxic or stable transformation products to be avoided

Applicability: Integration into existing infrastructure and operation by current personnel must be feasible

Cost/benefit: Material, energy, personnel, costs must be justifiable and competitive

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Initial Position

• Variety of processes from laboratory tests, industrial wastewater treatment, drinking water treatment

• Selection of 2 promising method for pilot testing "strategy Micropoll" (2006), graduating with pilot tests in 2010

• Applicability to large-scale implementations for municipal wastewater treatment in Switzerland?

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Overview of suitable processes

Adsorption• Activated carbon (PAC, GAC) • Precipitation• Ion exchanger• Zeolithe

Biologic degradation• Natural treatment (reed bed,

ponds, soil passage) • Technical process (sandfilter,

fluidized bed, …)

Oxidation• AOP • Chlorin/Chlordioxide • Ferrate • Ozone

Physico-chemical• Nanofiltration• Reverse osmosis

slide 18

Overview

The Swiss strategy

The Technologies• Powdered activated carbon• Ozone

Costs and Energy

slide 19

Process

Layout

Backwash Effluent

Filter bed

Contact Separation

Incineration

Adsorbent

Effluent2. clarifier

Effluent2. clarifier

PAC GAC

slide 20

Powdered activated carbon (PAC): Layout

Biologische Stufe

PAK-Abtrennung

Kontaktreaktor

RezirkulationÜberschuss: Rezirkulationoder Entsorgung

PAK-LagerungBenetzung und Dosierung

Fäll- und Hilfs-Mittel-Dosierung

PAC storageWetting + dosing

ConventionalWWTP

Spent PAC: returned to biologyor disposed incineration

Return

Separation

Additivesfor separation

Contactor

Experiences:• Swiss: Pilot trials Eawag,

Lausanne, Kloten/Opfikon • D: full scale WWTP• 2015: WWTP Herisau

slide 21

PAC: Mannheim

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PAC: Results

ARA-Mikroverunreinigungen, 2.-4.11.2011 Seite 23

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PAC: Characteristics

Broad band effectivity: very goodlittle removal for only few compounds (dependent on PAC

dose)Transformation products: none (complete mineralization in

case of incineration of spent PAC) PAC loss in the effluent unknown.

Applicability: simple integration in existing WWTPseveral layout options (separation): footprint vs. energyCorrosion/Abrasion

Cost/benefit: low energy requirement on site PAC activation energy demandingCosts ca. 0.05 – 0.4 Fr./m3

Good elimination of micropollutants, DOC, color, odour

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Overview

The Swiss strategy

The Technologies• Powdered activated carbon• Ozone

Costs and Energy

slide 25

Process

Layout

Inflow Effluent

Oxidant

Reactorslide 26

Ozonation: Layout Experience:• Swiss: Regensdorf,

Lausanne• D: various installations• 2014: WWTP Dübendorf

In biologische Stufe

OzongeneratorAbgasbehandlung

OzonungsreaktorSandfilter

Sauerstofftank Verdampfer

Nachklärung

Off gas treatmentO3 generator

Vaporizer Oxygen tank

2nd clarifier

Ozone reactor

To biology

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Piloting ozonation at full scale: Regensdorf

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Ozonation: Results

Dosing:0.67 gO3/gDOC (Regensdorf) 0.76 gO3/gDOC (Lausanne)

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80%

100%

Elim

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Regensdorf Lausanne

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Ozonation: Characteristics

Broadband removal: very goodLimited elimination for few compounds (dependent on ozone dose)

Transformation products: mostly unknown oxidation productsClear decrease of most toxic effects, no increaseFormation of bromate, nitrosamines (dependent on WW composition)

Applicability: goodknown safety regulationsMaintenance by specialists

Cost/benefit: increased energy consumption on site (+ 10 – 30%)Costs ca. 0.05 – 0.2 Fr./m3

Good elimination of micropollutants, color, odour, pathogens

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Overview

The Swiss strategy

The Technologies• Powdered activated carbon• Ozone

Costs and Energy

slide 31

PAC & Ozone: Piloting confirm good elimination

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Water quality: ecotoxicology

In-vitro biotests:clear toxicity reduction

In-vivo biotest: toxicityreduction or no increase

Energy consumption (local)Ozonation and PAC

Today Ozone (5 mg/L) PAC (12 mg/L)WWTP

Flow kWh/m3 0.36 0.06 0.02PE kWh/PE/y 38 8 2

Primary energyFlow kWh/m3 1 0.27 0.37PE kWh/PE/y 105 33 50

Total energy consumption in Switzerland: Wastewater treatment 480 GWh/a 0.8%Total electric power 57’670 GWh/a 100%

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Costs (local, full charge)Ozonation and PAC

Untersee Furt Au Zürich

Size PE 6100 37700 66000 600000

Average CHFlow Fr./m3 1.05 0.80 0.55 0.55

PE Fr./PE/y 118 87 61 61

Ozone (5 mg/L)Flow Fr./m3 0.18 0.09 0.08 0.04

PE Fr./PE/y 34 12 11 5

PAC(10 mg/L)Flow Fr./m3 0.30 0.18 0.15 0.09

PE Fr./PE/y 58 23 19 12

SandfilterFlow Fr./m3 0.16 0.13 0.07 0.05

PE Fr./PE/y 30 16 10 6

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Relative costs decrease with sizeAdvanced treatment costs ≤30% of today’s treatment costs

Conclusion

• Reducing the micropollutant load discharged to our surface waters makes sense and is feasible

• Centralized municipal wastewater treatment is a relevant point source

• Different technological options

• Feasible and competitive today are adsorption on PAC and ozonation

• Knowledge transfer and gathering full scale experience is important for allowing efficient solutions

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Thank you