IMPACT OF NOM AND NITRATE ON THE FEASIBILITY OF UV/H O 2 2 TREATMENT FOR ORGANIC MICROPOLLUTANT CONTROL

Transcription

1 IMPACT OF NOM AND NITRATE ON THE FEASIBILITY OF UV/H O 2 2 TREATMENT FOR ORGANIC MICROPOLLUTANT CONTROL Bram J. Martijn PWN Water Supply Company North Holland James P. Malley University of New Hampshire Joop C. Kruithof Wetsus Centre of Excellence for Sustainable Water Technology

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3 wtp Andijk 1968 Lake IJssel microstraining breakpoint chlorination coagulation rapid sand filtration post chlorination

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5 Lake IJssel wtp Andijk 1978 microstraining breakpoint chlorination coagulation rapid sand filtration GAC filtration GAC filtration microstraining chlorine dioxide dosage

6 PWN masterplan wtp Andijk pretreatment n coagulation with sludge blanket clarifiers not suitable for automation n pretreatment upgraded with modern technology: ultrafiltration posttreatment n retrofit with advanced treatment for disinfection and organic contaminant control: UV/H 2 O 2 treatment

7 surface water treatment at PWN retrofit wtp Andijk 2004 Lake IJssel coagulation rapid sand filtration UV/H 2 O 2 treatment GAC filtration GAC filtration ClO 2

8 PWN masterplan wtp Andijk pretreatment n coagulation with sludge blanket clarifiers not suitable for automation n pretreatment upgraded with modern technology: ultrafiltration posttreatment n retrofit with advanced treatment for disinfection and organic contaminant control: UV/H 2 O 2 treatment

9 surface water treatment at PWN retrofit wtp Andijk Lake IJssel IX-UF UV/H 2 O 2 treatment GAC filtration GAC filtration ClO 2

10 impact IX-UF pretreatment on feasibility UV/H O treatment, 2 2 wtp Andijk conditions and probe selection n water type: IX-UF n reference water types: direct UF (= raw), CSF, milliq n probe for photolysis: NDMA n probes for OH oxidation: 1,4-dioxane, pcba

11 impact IX-UF pretreatment on feasibility UV/H O treatment, 2 2 wtp Andijk outline research n water quality n UV spectra n photon flow n probe degradation by photolysis n probe degradation by OH-radical oxidation n application R UV, OH model n impact matrix

12 water quality results n UV transmittance determined by nitrate and NOM only reconstitution by dosing NOM and nitrate

13 NOM and nitrate content in direct UF, CSF and IX-UF treated IJssel Lake water 8 concentration [mg/l] 6 nitrate DOC UF CSF treatment IX-UF treatment

14 impact pretreatment on UV absorbing constituents: NOM and nitrate results n significant NOM removal and no nitrate removal by CSF n no NOM and nitrate removal by direct UF n significant NOM and nitrate removal by IX-UF

15 UV spectrum ultrafiltered IJssel Lake water 2 direct UF (raw water) UV absorbance [cm ] wave length [nm]

16 UV spectrum ultrafiltered IJssel Lake water and reconstituted water 2 direct UF (raw water) UV absorbance [cm ] reconstituted water wave length [nm]

17 UV spectrum CSF treated IJssel Lake water 2 UV absorbance [cm ] CSF treated water wave length [nm]

18 UV spectrum CSF treated IJssel Lake water and reconstituted water 2 CSF treated water UV absorbance [cm ] reconstituted water wave length [nm]

19 UV spectrum IX-UF treated IJssel Lake water UV absorbance [cm ] 2 IX-UF treated water wave length [nm]

20 UV spectrum IX-UF treated IJssel Lake water and reconstituted water 2 IX-UF treated water UV absorbance [cm ] reconstituted water wave length [nm]

21 UV spectra 2 UV absorbance [cm ] direct UF (raw water) CSF treated water IX-UF treated water wave length [nm]

22 impact pretreatment on UV spectra n confirmation NOM and nitrate removal n reconstitution based on NOM and nitrate only representative

23 percentage photon flow absorbed in UF, CSF and IX-UF matrix by 6 mg/l H O 2 2 UF CSF IX-UF 254 nm 2.6% 5.3% 14.7% 240 nm 4.5% 8.2% 19.4% increase absorbance H 2 O 2 with extended pretreatment increase absorbance H 2 O 2 at lower wave length

24 percentage photon flow absorbed in direct UF, CSF and IX-UF matrix UF CSF IX-UF H 2 O 2 NDMA 1,4-dioxane matrix n 6 mg/l H 2 O 2 n 500 μg/l NDMA n 200 μg/l 1,4-dioxane n wavelength distribution nm

25 percentage photon flow absorbed in direct UF, CSF and IX-UF matrix UF CSF IX-UF H 2 O 2 4% 6% 11% NDMA 1,4-dioxane matrix n 6 mg/l H 2 O 2 n 500 μg/l NDMA n 200 μg/l 1,4-dioxane n wavelength distribution nm

26 percentage photon flow absorbed in direct UF, CSF and IX-UF matrix UF CSF IX-UF H 2 O 2 4% 6% 11% NDMA 7% 9% 17% 1,4-dioxane matrix n 6 mg/l H 2 O 2 n 500 μg/l NDMA n 200 μg/l 1,4-dioxane n wavelength distribution nm

27 percentage photon flow absorbed in direct UF, CSF and IX-UF matrix UF CSF IX-UF H 2 O 2 4% 6% 11% NDMA 7% 9% 17% 1,4-dioxane 0% 0% 0% matrix n 6 mg/l H 2 O 2 n 500 μg/l NDMA n 200 μg/l 1,4-dioxane n wavelength distribution nm

28 percentage photon flow absorbed in direct UF, CSF and IX-UF matrix UF CSF IX-UF H 2 O 2 4% 6% 11% NDMA 7% 9% 17% 1,4-dioxane 0% 0% 0% matrix 89% 85% 72% n 6 mg/l H 2 O 2 n 500 μg/l NDMA n 200 μg/l 1,4-dioxane n wavelength distribution nm

29 photon flow calculations results n significant competition for photons between H 2 O 2 and matrix: UF > CSF > IX-UF n photolysis H 2 O 2 : significant impact wavelength n photolysis NDMA n no photolysis 1,4-dioxane: degradation by OH- radical oxidation only n highest impact on photon flow by matrix

30 NDMA degradation by UV/H O 2 2 in CSF treated IJssel Lake water UV dose [mj/cm 2 ] ln (c/c 0 ) [-] mg/l H2O2-6 6 mg/l H2O2

31 NDMA degradation by UV/H O 2 2 in IX-UF treated IJssel Lake water UV dose [mj/cm 2 ] ln (c/c 0 ) [-] mg/l H2O2 3 mg/l H2O2 5 mg/l H2O2 11 mg/l H2O2 15 mg/l H2O2-4 -6

32 NDMA degradation by UV/H O 2 2 in pretreated IJssel Lake water UV dose [mj/cm 2 ] UV dose [mj/cm 2 ] ln (c/c 0 ) [-] mg/l H2O2 3 mg/l H2O2 5 mg/l H2O mg/l H2O2 15 mg/l H2O mg/l H2O2 6 mg/l H2O2 IX-UF CSF

33 EEO for NDMA degradation by UV/H O treatment 2 2 in CSF and IX/UF pretreated IJssel Lake water 3 EEO [kwh/m 3 ] CSF kwh/m H 2 O 2 dose [mg/l]

34 EEO for NDMA degradation by UV/H O treatment 2 2 in CSF and IX/UF pretreated IJssel Lake water EEO [kwh/m 3 ] 3 2 IX-UF CSF 1.2 kwh/m kwh/m H 2 O 2 dose [mg/l]

35 degradation NDMA by UV/H O 2 2 treatment results n no impact H 2 O 2 dosage: photolysis only n no impact pretreatment on UV dose needed for degradation n pretreatment strong impact on EEO: EEO CSF > EEO IX/UF

36 1,4-dioxane degradation by UV/H O 2 2 in CSF treated IJssel Lake water UV dose [mj/cm 2 ] ln (c/c 0 ) [-] mg/l H2O2 6 mg/l H2O2 15 mg/l H2O2

37 1,4-dioxane degradation by UV/H O 2 2 in IX-UF treated IJssel Lake water UV dose [mj/cm 2 ] ln (c/c 0 ) [-] mg/l H2O2 3 mg/l H2O2 5 mg/l H2O2 11 mg/l H2O2 15 mg/l H2O2

38 1,4-dioxane degradation by UV/H O 2 2 in pretreated IJssel Lake water ln (c/c 0 ) [-] -1 UV dose [mj/cm 2 ] UV dose [mj/cm 2 ] mg/l H2O2 6 mg/l H2O2 15 mg/l H2O mg/l H2O2 5 mg/l H2O2 15 mg/l H2O2 CSF IX-UF

39 EEO for 1,4-dioxane degradation by UV/H O treatment 2 2 in CSF and IX-UF treated IJssel Lake water 3 EEO [kwh/m 3 ] 2.9 kwh/m 3 CSF H 2 O 2 dose [mg/l]

40 EEO for 1,4-dioxane degradation by UV/H O treatment 2 2 in CSF and IX-UF treated IJssel Lake water EEO [kwh/m 3 ] kwh/m 3 IX-UF CSF kwh/m H 2 O 2 dose [mg/l]

41 degradation 1,4-dioxane by UV/H O treatment 2 2 results n impact H 2 O 2 dosage: OH-radical oxidation n impact pretreatment on UV dose required for degradation: OH-radical scavenging by matrix n strong impact pretreatment and H 2 O 2 dose on EEO: EEO CSF > EEO IX-UF

42 radical exposure as a function of H O dose 2 2 for milliq,, CSF and IX-UF treated IJssel Lake water 3,0E-13 R OH, UV [M s m 2 J ] 2,0E-13 milliq CSF IX-UF 1,0E-13 0,0E+00 0,0 0,2 0,4 0,6 H 2 O 2 dose [M]

43 radical exposure as a function of NOM and nitrate concentration in milliq water 2,0E-13 R OH, UV [M s m 2 J ] milliq; 5.4 mg/l H2O2 1,0E-13 0,0E DOC / nitrate [mg/l]

44 radical exposure as a function of NOM and nitrate concentration in milliq water 2,0E-13 milliq; 5.4 mg/l H2O2 R OH, UV [M s m 2 J ] nitrate in milliq; 6.0 mg/l H2O2 1,0E-13 0,0E DOC / nitrate [mg/l]

45 radical exposure as a function of NOM and nitrate concentration in milliq water R OH, UV [M s m 2 J ] 2,0E-13 milliq; 5.4 mg/l H2O2 DOC in milliq; 6.8 mg/l H2O2 nitrate in milliq; 6.0 mg/l H2O2 1,0E-13 0,0E DOC / nitrate [mg/l]

46 impact matrix on radical exposure results n significant impact matrix on radical exposure: exposure IX-UF > exposure CSF n superior exposure in milliq water : exposure milliq >> exposure IX-UF n impact NOM on radical exposure larger than impact nitrate

47 IJssel Lake retrofit 2013 wtp Andijk IX-UF UV/H 2 O 2 treatment GAC filtration GAC filtration ClO 2

48 relation EED for 80% atrazine degradation as a function of UVT 254 EED 80% atrazine degradation (kwh/m 3 ) 1,0 0,8 0,6 CSF 0,4 IX-MF 0,2 0, UVT 254 (%)

49 conclusion n water matrix constituents NOM and nitrate determine the efficacy of the UV/H 2 O 2 process MP UV/H 2 O 2 reliable barrier for organic contaminant control in an integrated treatment approach

50 IMPACT OF NOM AND NITRATE ON THE FEASIBILITY OF UV/H O 2 2 TREATMENT FOR ORGANIC MICROPOLLUTANT CONTROL Bram J. Martijn PWN Water Supply Company North Holland James P. Malley University of New Hampshire Joop C. Kruithof Wetsus Centre of Excellence for Sustainable Water Technology

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