Removing microplastics from wastewater Dr. Bruno BARILLON SUEZ - - - PowerPoint PPT Presentation

Removing microplastics from wastewater

• Dr. Bruno BARILLON

SUEZ - CIRSEE

Workshop on emerging pollutants Brussels 24 October 2018

Global assessment

Workshop on Emerging pollutants, Brussels 2 I

WWTPs are a pathway for microplastics (MP) release in marine environment But only part of the overall microplastics emissions go through WWTPs To what extent do WWTPs act as a barrier for MP release ?

Microplastic Emission Pathway Model Graphical Representation

Source: EUNOMIA, final report, 2018

Project ECOSEASTEM

2013-2015

5 campaigns on WWTPs

 France, Italy  90,000 – 3,500,000 PE  Biological treatment (CAS, MBR) w/o primary treatment  Sampling: inlet /outlet

Remaining key questions

Sampling protocols and analytical methods not standardized: what do we measure ? Role of primary and secondary treatment in the microplastics removal ? Need for an add-on treatment ? In which cases ? Technology specifications ?

SUEZ commitment since 2013

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Retention rates: 80 - 95 % Mainly microfibers

Workshop on Emerging pollutants, Brussels

On-going collaborative MICROPLASTIC project

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Project

MICROPLASTIC 2015 - 2019

Funding

FUI (France)

Partners

Simplified operational method for quantification

Protocol definition Evaluation as part of GWRC round-robin test

Additional WWTP audits

 3 WWTPs in France with new analytical protocol  Focus on unit processes: primary, secondary and tertiary

Add-on treatment assessment

 Pre-selection of technologies: e.g. sand filter, dissolved Air Flotation,

mechanical filter

 Pilot implementation in France (2019)  Techno-economical assessment

Done To be done Done

Workshop on Emerging pollutants, Brussels

SUEZ commitment since 2013

5 I Workshop on Emerging pollutants, Brussels

Simplified operational method for MP quantification

Protocol definition

Sampling:

 Automatic samplers with glass bottles and Teflon pipes  Blanks for contamination assessment

 Analysis:

 Chemical pre-treatment: NaOH hydrolysis  Raw wastewater volume: 40 ml diluted with 160 ml deionized water  Treated wastewater: 200 ml  Filtration 2 µm on glass fibre  Visual counting with binocular magnifier

Raw wastewater X45 Analysis Sampling

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WWTP audits

Treatment lines

Sampling point Tertiary filtration

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WWTP audits

Microplastic removal

1735 210 185 50 5 12 500 1000 1500 2000 WWTP 1 WWTP 2 WWTP 3

MP / L

Inlet Outlet

 Variability in influent concentrations in the

range 200 – 1,500 MP/L

 Higher concentrations compared to literature

but sampling preparation with filtration @ 2µm

Significant role of primary decantation: 80

% MP removal in average

 MP removal inlet/outlet: 90 – 97 % when

primary and/or tertiary treatment

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Key questions

Where are we ?

Sampling protocols and analytical methods not standardized: what do we measure ?

 Development of an operational method for MP quantification by microscopy  Still, no standardized method in the literature

Role of primary and secondary treatment in the microplastics removal ?

 ~ 80 % of MP are removed by primary decantation  Global MP removal > 90 % if biological treatment with primary and/or tertiary treatment or if Membrane Bioreactor (> 95 %)  Global MP removal > 80 % if biological treatment but without primary and/or tertiary treatment

Need for an add-on treatment ? In which cases ?

 For WWTP without primary or tertiary treatment or WWTP not equipped with Membrane Bioreactor

Technology specifications ?

 Next phase of the MICROPLASTIC project with pilot implementation

Key points to be addressed

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 SUEZ has been advocating for EU action to be taken and considers that combined action

is required: at source, to prevent and reduce the presence of pollutants (micropollutants, microplastics,…) in effluents, and at end of pipe with the deployment of treatment technologies

 Contribution of stormwater drains should be assessed (as pathway for microplastics

emissions from tyres, for instance)

 Actions to be conducted / further investigated:

 Assess mass balances of microplastics going through WWTPs (% COD)  Quantify microplastics in sludge  Assess the impact on the disposal routes for the sludge

Workshop on Emerging pollutants, Brussels