ScorePP Dissemination Workshop (2-3 February 2010)

1. ScorePP Dissemination Workshop (2-3 February 2010) Comparison of technological treatment optionsMiddlesex University, Danish Technical University, University of Ljubljana, ENVICAT, Anjou Recherche.

2. Overall objectives To address the technologies available for eliminating the discharge of priority pollutants to receiving waters as a result of different activities and to carry out a comparative analysis to assess the most appropriate and feasible reduction technologies

3. Treatment options considered in ScorePP • Stormwater BMPs • Greywater treatment and reuse systems for household wastewater • Industrial wastewater treatment • Municipal wastewater treatments • Sludge disposal • Assessment of the feasibility of the different treatment options for PPs

4. Stormwater Best Management Practices

5. Stormwater BMPs • Structural and non-structural • Constructed wetlands • Detention basin • Retention pond • Lagoon • Green roof • Settlement tank • Filter strips • Swales • Infiltration basins • Soakaways • Porous asphalt • Porous paving • Stormwater control systems close to the source • Control water quantity & quality • Provide social amenity • Infiltration/detention followed by discharge at a controlled rate • Used individually, in a treatment train or in combination with conventional piped systems

6. Fundamental unit Physical processes Biological processes Chemical processes Adsorption, Settling, Filtration, Volatilisation Flocculation, Precipitation, Photolysis Plant/algal uptake, Microbial degradation BMP characteristics which influence removal processes: dry & wet area/volumes; retention & drain down times; surface exposure times; hydraulic/flow attenuation; vegetative, algal & microbial components; presence of sorption sites/nature and pore sizes of substrate; existence of aerobic/anaerobic conditions Pollutant behaviour: Susceptibility of a particular pollutant to the identified processes Identification of the potential pollutant removal efficiency within a specific BMP

7. Order of preference for the use of BMPs to remove Pb and Benzo (a) pyrene

8. Comparison of theoretical ranking with measured data: Organic PPs in SSF CW

9. Summary of the ability of stormwater BMPs to remove PPs • In the absence of field data, enables end-users to evaluate BMPs from the perspective of the removal of non-standard pollutants of concern; demonstrates critical discrimination across BMPs although infiltration basins and sub-surface flow constructed wetlands consistently rank most highly for the removal of priority pollutants • BMP order of preference for the removal of PPs compares well with field data available to date but more field data required to refine and calibrate this approach • Provides input to development of emission control strategies (e.g. ScorePP) • Does not take into consideration the suitability of different options for specific geographical locations, e.g. potential for groundwater contamination due to infiltration in unsuitable soil type.

10. Household Greywater Treatment and Reuse Systems

11. Household greywater • GREYWATER = BATHROOM (sinks, baths and showers) KITCHEN (sinks, dishwashers) LAUNDRY (sinks, washing machines) NO TOILET WASTE • Previous research has concentrated on conventional water quality monitoring parameters (e.g. BOD, TSS, nutrients, and pathogens). • Increasing support for decentralised WWT – increasing pressures on water supplies, improved potential for recycling, water savings etc. • Difficult to draw conclusions about the efficiency of the various treatment options (individually or in a train) for PS/PHS in greywater • The majority of removal efficiency studies relate to treatment of combined wastewater • Greywater treatment is highly site-specific, wide range of treatment trains, many still in development or pilot stage • Lack of data on micropollutant treatment efficiency. Only 1 greywater study reporting both inlet and outlet concentrations of PS/PHS.

12. Information reviewed Priority substance properties Priority substance sources Greywater Pre-treatment systems Priority substance presence Recycling systems Priority substance concentrations/ loads Greywater reuse Removal efficiencies Operational risks Electricity consumption Chemical consumption Cost-benefit analysis Health risks connections Risks to the environment Operational costs Installation costs Water savings Nutrient recycling

13. RBC, Nordhavnsgården, Copenhagen A0 A2 A3 A4 A6 A7 A1 A5 Primary settling tank Service water tank Sand- filter UV-filter Multi-stage Rotating Biological Contactor Secondary settling tank • Proportional potable water use volumes and wastewater volumes based on Danish water use statistics (DANVA, 2007; Kjellerup and Hansen, 1994; Nordhavnsgården monitoring data).

14. GW treatment and reuse scenarios

15. Example of a treatment and reuse scenario

16. Greywater pollutant dynamics (cadmium) Irrigation 0 µg p-1 d-1 Irrigation Greywater Treatment Plant 3.039 µg p-1 d-1 [A] Bathroom 3.039 µg p-1 d-1 Laundry 0 µg p-1 d-1 Potable water Laundry 4.65 µg p-1 d-1 [D] [B] Toilet 11.155 µg p-1 d-1 Sludge 2.735 µg p-1 d-1 Kitchen 1.58 µg p-1 d-1 [C] Surplus 0.109 µg p-1 d-1 No decrease in load to WWTP unless sludge is removed Toilet 0 µg p-1 d-1 Municipal Wastewater Treatment Plant 20.229 µg p-1 d-1 [E] Decrease in WWTP Cd influent loading of 2.74 µg p-1 d-1 [F] Potential Cd removal efficiency of 13.5 % Potable H2O saving = 27 l p-1 d-1 (23 %) WWTP influent reduction = 11 %

17. Summary of Greywater Treatment scenarios • Domestic greywater is a significant source of micropollutants to the urban water cycle but there is a lack of knowledge about micropollutant presence and fate in greywater • Wide range of potential greywater treatment trains and reuse options; combined with the variable pollutant characteristics makes modelling difficult. • Sludge management is critical in determining the emission barrier potential • WFD PS/PHS not necessarily highest priority in terms of quantity used and/or risks associated with use • Need to employ source control measures for decreasing the Greywater pollutant contents (e.g. green labeling and procurement, substitution options, information campaigns, and regulatory controls).

18. On-site treatment systems for industrial wastewater

19. Classification of BAT techniques Industrial wastewater treatment processes appropriate for the removal of suspended solids and insoluble liquids (6 techniques identified as A1 to A6) • Industrial wastewater treatment processes appropriate for the removal of inorganic/non-biodegradable/poorly biodegradable soluble pollutants (15 techniques identified as B1 to B15) • Biodegradable soluble pollutants (4 techniques identified as C1 to C4)

20. Industrial wastewater treatment database for individual PPs • CAS number • Emission String number • Production process • NOSE-P classification • Production activity • NACE classification • Possibilities for substitution • Applicable treatment processes • BREF code of relevant document • Treatment efficiency and/or achievable emission levels

21. Extract from Cd database (specific treatment)

22. Extract from Cd database (generic treatment)

23. Summary of Industrial Wastewater Treatment • Databases for 25 non-substitutable industrial PPs showing on-site reductions (removal efficiencies or achievable effluent levels) show a variability of data availability and a wide range of different performances. • Information relating to a specific pollutant is often limited and therefore generic techniques relating to similar pollutant characteristics or overall treatment type are also included. • The scientific principles involved in the treatment processes together with the equipment and process details are well established.

24. Municipal wastewater treatment plants

25. Topics addressed • Removal of pollutants in conventional and alternative wastewater treatment plants • Fate of priority pollutants in different treatment stages in conventional waste water treatment plants • Tools to predict the removal and fate of priority pollutants in WWTP

26. Example of modelling results for primary treatment Percentage removal per mechanism during primary wastewater treatment according to the three tested models

27. Example of modelling results for secondary treatment Percentage removal per mechanism during secondary wastewater treatment according to the three tested models for pollutants with log Kow < 4.5

28. Summary of municipal wastewater treatment • Experimental data exists for 14 of the priority substances originally identified in the WFD • The removal and fate of an additional 19 priority substances has been predicted using a combination of models (Byrns; FATE; STPWIN) • Overall, the data collected on 33 priority pollutants can be summarised as: • 19 pollutants presented a removal efficiency higher than 80% (benzene, naphthalene, tetrachloroethylene, chlorfenvinphos, 1,2,4-trichlorobenzene, pentachlorophenol, endrin, p-p-DDT, fluoranthene, nonylphenols, hexachlorobenzene, 4-para-nonylphenol, benzo(b)fluoranthene, aldrin, benzo(g,h,i)perylene, o-p-DDT, DDE, DEHP and PBDE), • 12 PPs exhibited removal efficiencies between 50 and 80% (methylene chloride, chloroform, trichloroethylene, carbon tetrachloride, lindane, α-endosulphan, HCH, octylphenols, anthracene, dieldrin, DDD and benzo(a)pyrene) • 2 PPs (simazine and atrazine) demonstrated removal efficiencies lower than 40%.

29. PP behaviour in wastewater sludges and evaluation of sludge disposal options

30. Sludge production and treatment WW treatment systems producing sludge • Municipal wastewater treatment • e.g. Anaerobic digestion (focus in ScorePP), membrane bioreactors • Industrial wastewater treatment • e.g. Sedimentation tanks, Coagulation/flocculation, membrane filtration systems • Stormwater treatment systems • e.g. Sedimentation tank, detention ponds/basins (dry ponds), retention ponds/basins (wet ponds), constructed wetlands • Greywater treatment systems • e.g. multi-stage rotating bioreactors, membrane bioreactors, soil filter systems – normal removal process leads to a build-up of sludge/sediment. Sludge treatment options • Thickening, dewatering (centrifugal, pressure based, electrokinetic), stabilisation, conditioning, thermal reduction, sludge pasteurisation, aerobic digestion, anaerobic digestion (mesophilic and thermophilic), drying, composting, storage.

31. Summary of sludge treatment • Primarily designed to reduce volume, odour and pathogenic risk prior to disposal/reuse • Guideline limits will become increasingly stringent for sludges being disposed of by agricultural land application, landfilling or incineration. • Reuse options encouraged where feasible e.g. sewage sludge in building materials, metal recovery from electroplating sludge, exploitable by-products. • The sustainability of many reuse options need careful examination

32. Assessment of the feasibility of treatment options.

33. Priority Pollutant Focus Feasibility assessment has concentrated on 12 PPs. • Benzene • Benzo(a)pyrene • Cadmium • Chlorpyrifos • DEHP (Di-(2-ethylhexyl)-phthalate) • Diuron • EDC (ethylene dichloride) • Lead • Mercury • Nonylphenol • PBDE (pentabromodimethylether)

34. Agreed criteria for treatment techniques

35. Scored matrices – Lead example

36. Summary of treatment feasibility approach • A treatment feasibility approach has been developed despite the existence of data gaps and the problems associated with non-comparability of inconsistent units • Scoring protocols have been allocated according to the available data but may not be suitable for all situations e.g. the relevance of the local context • Some parameters (e.g. pollutant removal efficiencies; dilution ratios) may be oversimplifications in representing specific criteria.

37. Application to substance flow analysis (SFA) approach

38. Treatment barrier database Treatment Barrier Database Information on a selected treatment Assessment of the potential treatments

39. Conclusions • A unit process based approach applied to stormwater treatment by BMPs enables removal of PHS/PS to be assessed. • Greywater treatment and reuse can make a valuable contribution to potable water savings and WWTP flow reductions but quality improvements are strongly dependent on sludge management • The existing BAT techniques together with developing treatment options demonstrate taht a comprehensive range of efficient options are available for the industrial control of PPs in process waters.

40. Conclusions (continued) • A combination of experimental and modelling data provides relevant information regarding the removal of PHS/PS in conventional WWTPs. • Sludge treatment needs serious future consideration as it is becoming increasingly unacceptable to practice current disposal routes for contaminated sludges. • A treatment feasibility approach has been developed and provides the basis for a multi-criteria analysis.