The Future of Treatment: Advanced Technologies for Emerging Contaminants

Transcription

1 The Future of Treatment: Advanced Technologies for Emerging Contaminants

2 Drivers for Advanced Technologies As water resources are stressed, utilities often forced to consider less pristine sources Wastewater reuse Indirect Potable Reuse Direct Potable Reuse Polluted sources Everyone is downstream from someone What does treatment for EC s in DPR Look Like? 2

3 Full Available Treatment (FAT) EMERGING CONTAMINANT TREATMENT 3

4 Alternative Treatment (As Conditions Allow) EMERGING CONTAMINANT TREATMENT 4

5 How Much Treatment is Needed? 5

6 Process Descriptions Oxidation / Transformation Adsorption / Removal

7 A Recurring Theme Treatment processes either remove or change chemicals in water Removal is good but leaves you with a concentrated waste stream Change is good but leaves you with questions about what remains in the water Membranes and adsorption remove chemicals from water Ozone, UV, and Advanced Oxidation processes change chemicals in water 7

8 Membranes Thin barrier to constituents in water What gets through depends on size Feed Side Microfiltration (MF) Ultrafiltration (UF) Nanofiltration (NF) Reverse Osmosis (RO) Particle Removal Molecule Removal Molecule removal requires much more energy Reject H 2 O Permeate 8

9 Size Ranges of Membrane Processes and Contaminants Molecular Weight , , ,000 Micron Scale Typical Size Range of Selected Water Constituents Salts Dissolved Organics Viruses Colloids Bacteria Giardia Cryptosporidium Sand Membrane Processes Nanofiltration Reverse Osmosis Ultrafiltration Microfiltration 9

10 Sorption If substances don t like being in water (hydrophobic) they will prefer interactions with a solid material We can take advantage of this to remove many organics Activated carbon, ion exchange, zeolites H 2 O Carbon 10

11 Advanced Oxidation An effective process for disinfection and chemical oxidation, capable of providing barriers for protecting public health and improving public perception Pharmaceuticals, Personal Care Products, EDCs Crypto, Viruses, E. coli, etc. AOPs work by creating hydroxyl radicals ( OH) ( OH) then blast away organic chemicals Usually an expensive chemical process Complex chemistry 11

12 How Do We Make OH Light Oxidation Processes: UV Light + Ozone (UV/O 3 ) UV Light + Peroxide (UV/H 2 O 2 ) UV Light + Ozone + Peroxide (UV/O 3 /H 2 O 2 ) UV Light + Titanium Dioxide Dark Oxidation Processes: Ozonation at high ph (>8.5) Ozone + Peroxide (O 3 / H 2 O 2 ) Fenton System (H 2 O 2 /Fe 2+ ) Ozone + EfOM (Wastewater) 12

13 Differences between UV Disinfection and AOP Some fundamental differences in: Levels of Applied UV Energy Fundamental Mechanisms UV Dose (i.e. what does it mean?) Different Targets Disinfection Photolysis AOP 13

14 Ozonation O 3 is a very strong chemical oxidant When O 3 decays naturally, OH are formed Always some AOP going on when you ozonate O 3 produces more OH at higher ph ( > 8.5) (Note: higher ph can result in more bromate formation) Highly effective at oxidizing EDCs and PPCPs especially: Alkene Amine Phenol 14

15 Ozone + H 2 O 2 Very effective way to make OH, and fairly simple design Generally improved removal by only to 15 % Should be considered when contact time is unavailable for destruction by ozone alone 2O 3 + H 2 O 2 2 OH + 3O 2 15

16 How Effective are Advanced Processes for Treatment of Emerging Contaminants?

17 MBR HiPOx - RO Units MBR Influent MBR Filtrate RO Permeate (no oxidation treatment) RO Permeate (1. 5 mg/l O3 preoxidation) Atenolol ng/l 3, < 25 < 25 Atrazine ng/l < 10 < 10 < 10 < 10 Carbamazepine ng/l < 10 DEET ng/l < 25 < 25 Meprobamate ng/l 2, < 10 < 10 Dilantin ng/l < 10 < 10 Primidone ng/l < 10 < 10 Sulfamethoxazole ng/l 2,800 1,400 < 25 < 25 Trimethoprim ng/l 1, < 10 < 10 TCEP ng/l < 200 < 200 Bisphenol A ng/l 250 < 50 < 50 < 50 Diclofenac ng/l < 25 < 25 Gemfibrozil ng/l 5, < 10 < 10 Ibuprofen ng/l 30, < 25 < 25 Musk Ketone ng/l < 100 < 100 < 100 < 100 Naproxen ng/l 29, < 25 < 25 Triclosan ng/l < 25 < 25 MBR is a low-pressure membrane (with biological activity). Capable of removing 16-99% RO is a high-pressure membrane. Capable of removing to detection limit 17

18 Scottsdale CEC Removal Comparison (New and Old Membrane) Compound Avg. ROF ng/l Avg. ROP ng/l New Membrane % removal Acetaminophen Caffeine Carbamazepine Fluoxetine Gemfibrozil Ibuprofen Meprobamate Sulfamethoxazole Trimethoprim Old Membrane % removal Tricolsan, Estrodial, Ethnyestrodial, Progesterone not in feedwater 18

19 Scottsdale Nitrosamine Removal Comparison (New and Old Membrane) Compound Avg. ROF ng/l Avg. ROP ng/l New Membrane % removal N-Nitrosodiethylamine NDEA ND N D Old Membrane % removal N-Nitrosodimetylamine, NDMA N-Nitrosodi-N-Butylamine, NDBA ND ND N-Nitrosodi-N-Propylamine, NDPA ND ND N-Nitrosomethylethylamine, NMEA ND ND N-Nitrosomorpholine, NMOR N-Nitrosopiperidine, NPIP N-Nitrosopyrolidine, NPYR

20 Activated Carbon 0% % Log K OW = Caffeine Carbamazepine Atrazine DEET Acetaminophen Log K OW = 2.18 % Removal Dilantin Diclofenac Estriol Triclosan Ibuprofen Log K OW = 3.91 Testosterone Data compiled from AwwaRF,

21 Adsorption Processes MIEX >80% Removal Diclofenac Triclosan Bed Volumes to 10% Breakthrough >50,000 BVs 20,000 50,000 BVs <20,000 BVs Androstenedione Estradiol Estrone Ethinylestradiol Fluoxetine Oxybenzone Progesterone Testosterone Triclosan GAC Acetaminophen Atrazine Caffeine Carbamazepine DEET Diazepam Erythromycin Estriol Hydrocodone Pentoxifylline Trimethoprim Dicolfenac Dilantin Gemfibrozil Ibuprofen Iopromide Meprobamate Naproxen Sulfamethoxazole TCEP 50 80% Removal Naproxen 20 50% Removal < 20% Removal Dilantin Estradiol Ethinylestradiol Gemfibrozil Ibuprofen Oxybenzone Sulfamethoxazole Acetaminophen Androestenedione Atrazine Caffeine Carbamazepine DEET Diazepam Estriol Estrone Fluoxetine Hydrocodone Iopromide Mebrobamate Pentoxifylline Progesterone TCEP Testosterone Trimethoprim 21

22 Full-Scale Ozonation Water Treatment Plant 0% % Testosterone DEET Caffeine Erythomycin % Removal Galaxolide Estrone 17B-Estradiol Ibuprofen TCEP Naproxen Triclosan Data compiled from AwwaRF, Removal of EDCs and Pharmaceuticals in Drinking and Reuse Treatment Processes,

23 Ozonation of Wastewater Effluent 0% % % Removal Caffeine DEET Erythomycin Hydrocodone Ibuprofen Naproxen TCEP Oxybenzone Trimethoprim AwwaRF, 2007, Removal of EDCs and Pharmaceuticals in Drinking and Reuse 23

24 % Removal Ozone AOP Removal of Sulfamethoxazole Ozone Ozone/Hydrogen Peroxide Applied Ozone Dose (mg/l) % Removal Removal of TCEP Ozone Ozone/Hydrogen Peroxide Applied Ozone Dose (mg/l) % Removal Removal of DEET Ozone Ozone/Hydrogen Peroxide Applied Ozone Dose (mg/l) % Removal Removal of Dilantin Ozone Ozone/Hydrogen Peroxide Applied Ozone Dose (mg/l) 24

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26 UV Advanced Oxidation UV light alone at disinfection ( mj/cm 2 ) and chemical treatment ( mj/cm 2 ) doses is not effective at EDC/PPCP degradation UV + Hydrogen Peroxide (UV+H 2 O 2 2 OH) % Degradation 1000 mj/cm 2 LP, 0 mg/l H 2 O 2 MP, 0 mg/l H 2 O 2 LP, 15 mg/l H 2 O 2 MP, 15 mg/l H 2 O 2 Rosenfeldt and Linden, Environmental Science and Technology,

27 UV/H2O2 Oxidation of Estrogenic Activity UV + H 2 O 2 capable of removing > 90% estrogenic activity at < 400 mj cm -2 UV Dose 27

28 Not All AOPs are effective for all contaminants Chemical Log Reduction per Unit of Power Draw TCE UV-Oxidation UV-Photolysis NDMA 1,4-Dioxane ppm H2O2 14 ppm H2O2 7 ppm H2O2 14 ppm H2O2 7 ppm H2O2 14 ppm H2O2 28

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30 Case Study - Pilot Advanced Treatment Evaluation in Hollywood, FL 30

31 Emerging contaminant removal Complying with CA Rules Demonstrate >0.5 log (69%) Removal of surrogates from A - G Functional Group (A) Hydroxy Aromatic Example Compounds Acetominophen, Bisphenol A, Estrone, Triclosan (B) Amino/Acylamino Aromatic Atorvastatin, Sulfamethoxazole (C) Nonaromatic C=C (D) Deprotonated Amine (E) Alkoxy Polyaromatic (F) Alkoxy Aromatic (G) Alkyl Aromatic Carbamazepine, Codeine, OTNE Fluoxetine Caffeine, Trimethoprim Naproxen, Propranolol Gemfibrozil, Hydrocodone DEET, Dilantin, Ibuprofen, Primidone 31

32 Demonstrate >0.3 log (50%) Removal of surrogates from H or I Functional Group (H) Saturated Aliphatic (I) Nitro Aromatic Example Compounds Iopromide, Meprobamate Atrazine, Musk ketone, Musk xylene 32

33 Treatment Trains Evaluated Monitored ALL regulated contaminants + surrogate framework for unknowns 33

34 Pilot setup at SRWWTP (continued) DBF IX Secondary Effluent BAC UV AOP or Ozone 34

35 Pilot demonstrated appropriate emerging contaminant oxidation for key parameters Emerging Contaminant Functional Group Anticipated Drinking Water Guideline Pilot Influent Scheme 1 UV Dose of 400 mj/cm 2 Scheme 2 Ozone Dose of 5-8 mg/l 1,4 Dioxane < 2.0 (2) < 2.0 (2) < 2.0 (2) Atrazine I 3, < 1.3 (2) < 1.6 (2) Carbamazepine C < 10 (2) < 10 (2) Dilantin G < 103 (2) < 103 (2) Fluoxetine D 3, < 26 (2) < 26 (2) Gemfibrozil F 15, < 26 (2) < 26 (2) Iopromide H 1,750,000 < 51 (2) < 51 (2) <115 (2) Naproxen E 45,500 < 51 (2) < 51 (2) < 51 (2) Sulfamethoxazole B 151, < 10 (2) < 16 (2) Triclosan A 105, < 52 (2) < 52 (2) NDMA

36 Process scheme 1: NDMA formation in the BAC 36

37 Process scheme 2: NDMA limit not met 37

38 Additional process scheme 2b tested for NDMA oxidation post BAC filters DBF IX OZONE UV BAC 38

39 Process scheme 2b: NDMA limit met 39

40 Emerging contaminant removal summary Emerging Contaminant Functional Group CA Log Removal Scheme 1 UV Dose of 400 mj/cm 2 Scheme 2 Ozone Dose of 5-8 mg/l Scheme 2b UV Dose of 1000 mj/cm 2 1,4 Dioxane Not found Not found --- Atrazine I 0.3 >1.1 > Carbamazepine C 0.5 >1.0 > Dilantin G 0.5 >0.1 > Fluoxetine D 0.5 >0.1 > Gemfibrozil F 0.5 >1.7 > Iopromide H 0.3 Not found Not found --- Naproxen E 0.5 Not found > Sulfamethoxazole B Triclosan A 0.5 >0.7 > NDMA N/A N/A >0.7 *N/A = effluent concentrations above influent concentrations **Representative of pilot operation sampling data from Jan to Nov

41 Emerging contaminant summary Emerging Contaminant Functional Group CA Log Removal Scheme 1 Scheme 2 1,4 Dioxane Not found Not found Atrazine I 0.3 Yes Yes Carbamazepine C 0.5 Yes Yes Dilantin G 0.5 Yes Yes Fluoxetine D 0.5 Yes Yes Gemfibrozil F 0.5 Yes Yes Iopromide H 0.3 Yes Yes Naproxen E 0.5 Yes Yes Sulfamethoxazole B 0.5 Yes Yes Triclosan A 0.5 Yes Yes NDMA Yes After BAC Stabilization *Representative of pilot operation sampling data from Jan to Nov Yes With Process Scheme 2B 41

42 Summary Two classifications for advanced treatment processes Oxidation processes destroy contaminants, but leave you with unknown byproducts Removal processes separate contaminants from water, but leave you with a concentrated residual Advanced oxidation capable of degrading trace organics Destroy contaminants, and also destroy activity of contaminants Not all AOPs are equally effective for all contaminants High pressure membranes provide effective barriers against emerging contaminants Capable of removing contaminants to the limits of detection Lots of ways to get rid of micro-pollutants, but at what cost?? 42

43 One Final Thought As analytical detection continues to improve, we will find new emerging contaminants in drinking water. Advanced treatment processes will effectively treat EDCs and pharmaceuticals, but more than that, they can be studied in such a way that we understand whether they will be effective in treating the next set of emerging contaminants. How can advanced treatment processes be beneficial as you aim to do more than what the public asks to protect health? 43