Peter Schauer Chris debarbadillo PNCWA 2009

Transcription

1 Pushing the Envelope with Low Phosphorus Limits Peter Schauer Chris debarbadillo PNCWA 2009

2 Agenda Phosphorus removal overview Getting even lower Types of treatment Pilot testing Concluding remarks 2

3 Phosphorus Removal Overview Generally remove 1/3 to 1/2 of influent P through primary and secondary treatment Primary Settling removes some particulate P Conventional Biological Treatment Hydrolyzes much of the remaining particulate P Utilizes some soluble P for bacterial growth Additional P removal Chemical precipitation Biological 3

4 Phosphorus Removal Overview Effluent TP = 1 to 3 mg/l Convert to bio-p and/or add chemicals Effluent TP = 0.15 to 1 mg/l Add filters Chemical trim at clarifiers Effluent TP < 0.1 to 15 mg/l Need tertiary polishing with chemicals le Cost Relative Life Cycl Chemical Addition Effluent TP in mg/l Conversion to BNR 4

5 McDowell Creek WWTP Biological Phosphorus Removal + Filters Effluent TP (mg/l) 30 per. Mov. Avg. (Effluent TP (mg/l)) 1999 Average = 0.40 mg/l 2000 Average = 0.28 mg/l 2001 Average = 0.20 mg/l 2002 Average = 0.14 mg/l 2003 Average = 0.15 mg/l 2004 Average = 0.13 mg/l 2005 Average = 0.21 mg/l Phosphorus, mg/l Historical Monthly Avg P Limit = 1 mg/l 0 12/1/1999 3/1/2000 6/1/2000 9/1/ /1/2000 3/1/2001 6/1/2001 9/1/ /1/2001 3/1/2002 6/1/2002 9/1/ /1/2002 3/1/2003 6/1/2003 9/1/ /1/2003 3/1/2004 6/1/2004 9/1/ /1/2004 3/1/2005 6/1/2005 9/1/ /1/2005 3/1/2006 5

6 Northwest Cobb WRF Chemical Phosphorus Removal + Filters FY 2001 Average = 0.13 mg/l TP FY 2002 Average = 0.16 mg/l TP FY 2003 Average = 0.10 mg/l TP mg/l 30 per. Mov. Avg. (mg/l) Total Phosphorus, s, mg/l Monthly Average TP Limit = 0.6 mg/l MDL for Effluent TP reduced to 0.05 mg/l /01/00 03/01/00 04/30/00 06/29/00 08/28/00 10/27/00 12/26/00 02/24/01 04/25/01 06/24/01 08/23/01 10/22/01 12/21/01 02/19/02 04/20/02 06/19/02 08/18/02 10/17/02 12/16/02 02/14/03 04/15/03 06/14/03 Monthly Average TP Limit = 0.23 mg/l 6

7 Impact from Effluent Solids Effluent TP Concentra ation, mg/l Impact of Effluent TSS on TP OP = 0.01 mg/l OP = 0.10 mg/l OP = 0.30 mg/l OP = 0.50 mg/l OP = 0.70 mg/l Effluent TSS Concentration, mg/l 7

8 Some Phosphorus Sensitive Watersheds 0.35 Phospho orus Limit, mg/l Chesapeake Bay Potomac River Lower Catawba River Atlanta Metro Limits Tualatin River Lake Simcoe, Ontario Colorado Lakes Spokane River 8

9 Getting Even Lower Less than 0.1 mg/l TP Chemical reactive P Filtration particulate P Chemical reactions at low concentrations are an area of research Indications are that 0.01 to 0.02 mg/l is achievable, but very difficult 9

10 Forms of Phosphorus Total Phosphorus Dissolved Particulate Acid Hydrolysable P Organic P Ortho P Complex Phosphates 10

11 Type of Treatment Tertiary Clarifier + Filters Ballasted Flocculation + Filters Dual Filtration Membranes 11

12 Tertiary Clarification + Filters Tertiary clarifiers Conventional, solids contact, lamella Filters needed to further reduce solids Well established technology Larger footprint compared to some of the newer technologies 12

13 Some Full Scale WWTPs Operating for Ultra-low P Using Tertiary Clarifier or Lamella Settlers WPCP Capacity (mgd) Technology Effluent TP (mg/l) Farmer s Korner WPCP (CO) 3 Tertiary clarifiers, sand filters <0.01 Snake River WPCP (CO) 2.6 Rock Creek AWWTF (OR) 39 Durham AWWTF (OR) 24 F. Wayne Hill (GA) 60 Flocculation/ sedimentation, mixed media filtration Tertiary clarification, granular media filtration BPR + tertiary clarification, granular media filtration Tertiary clarification with lime, filters + membranes < <0.08 Alexandria (VA) 54 Inclined plate settlers + filters <0.07 UOSA (VA) 42 Tertiary clarification with lime, filters <0.09 Fairfax County WPCP (VA) 67 Tertiary clarification, filtration <

14 Ballasted Flocculation + Filters Ballast, such as microsand, sludge, or magnetite is added to the wastewater to enhance settling Small footprint ( high-rate ) settling Filters needed to further reduce solids Actiflo, Densadeg, CoMag 14

15 Some Full Scale WWTPs Operating for Ultra-low P Using Ballasted Flocculation Processes WPCP Capacity (mgd) Technology Effluent TP (mg/l) Iowa Hill WPCP (CO) 1.5 DensaDeg + filters Lindsay (Ontario) 5.7 Actiflo + filters 0.03 to 0.09 West Palm Beach (FL) Actiflo + filters 0.04 Concord (MA) 2 CoMag + filters 0.04 Notable Pilots Actiflo (Everglades, FL; New Tecumseth, Ontario) Densadeg (New Tecumseth, Ontario) Co-mag (Concord, MA) 15

16 Dual Filtration Two filters in series DynaSand D2 Blue Water Technologies Adsorption on Iron Oxide Coated Sand Reactive filtration FeCl 3 Secondary Clarifier Pre-reactor time + dose IOCS Effluent P 0.05 mgp/l with one pass filters 0.01 mgp/l with two pass filters 16

17 Some Full Scale WWTPs Operating Dual Filtration Processes for Ultra-low P WPCP Capacity (mgd) Technology Effluent TP (mg/l) Walton (NY) 1.55 D to 0.05 Stamford (NY) 0.5 D Manotick (Ontario) D Hayden (ID) 1.2 BluePro 0.02 Notable Pilots D2 (Coeur d Alene, ID; Spokane, WA) BluePro (Coeur d Alene, ID; Spokane, WA, Florida pilot) 17

18 Membranes Membrane Bioreactors BioP with chemical addition Chemical addition only Tertiary filtration membranes With chemical addition 18

19 Some Full Scale WWTPs Operating for Ultra-low P Using membranes or MBR WPCP Capacity (mgd) Technology Effluent TP (mg/l) City of Ashland (OR) 2.3 ZeeWeed MBR Process <0.05 Lonetree WPCP (CO) 2.4 ZeeWeed MBR Process Cauley Creek (GA) 5 ZeeWeed MBR Process <0.13 Broad Run WRF (VA) 10 ZeeWeed MBR Process <0.04 F. Wayne Hill (GA) 60 Tertiary clarification with lime, filters + membranes <

20 Some Other Options Dissolved Air Flotation followed by filters Absorptive medias Granulated ferric hydroxide (e.g., Kemiron CFH-12) Activated aluminum oxide Asahi Kasei orthophosphate-selective adsorbent 20

21 Reverse Osmosis Bundamba reuse scheme, Brisbane, Australia Pretreatment including chemp removal MF, RO UV-Peroxide RO permeate TP typically <0.01 mg/l 21

22 Bundamba Western Corridor Recycled Water Project Total Phosp phorus, mg/l /17/2008 4/22/2008 4/27/2008 5/2/2008 5/7/2008 5/12/2008 5/17/2008 5/22/2008 5/27/2008 Date 22

23 Innisfil Pilot Test Target Effluent TP Concentrations Based on phosphorus allocation of 351 kg TP/year or 0.96 kg TP/day Parameter Phase 1 Phase 2 Effluent Average Month Total Phosphorus, mg/l Effluent Maximum Month Total Phosphorus, mg/l

24 Goal of Pilot Study Meeting 0.01 mg/l? Removal using different technologies Ballasted flocculation Double filtration Membranes Absorption? Pilot Phase Optimization Steady State Operation Diurnal Flow Variation Stress Testing Activities Steady state, dose variation Steady State MMF 60% - 140% MMF PDF PHF 24

25 GE Tertiary Ultrafiltration Membrane System 25

26 Blue PRO Iron Oxide Coated Sand Dual Filtration System 26

27 Veolia ACTIFLO Process followed by Gravity Filters 27

28 Parkson DynaSand D2 Dual Filtration System 28

29 Conclusions / Areas of Research Phosphate complexation recent Water Environment Research articles Sampling and analytical accuracy at very low levels Ongoing development of phosphorus adsorption processes for wastewater treatment Further development of phosphorus recovery processes 29

30 For More Information EPA Report, April 2007 Advanced Wastewater Treatment to Achieve Low Concentration of Phosphorus WERF Nutrient Challenge website WEF/WERF Workshop 101 at WEFTEC 2008 Neethling et al, 2007 (WEF Nutrient Conference, paper on phosphorus speciation) Some recent articles in Water Environment Research Newcombe et al, 2008a and 2008b (articles on hydrous ferric oxide reactive filtration, March 2008) Szabo et al, 2008 (chemp design and operational variables) Smith et al, 2008 (phosphate complexation model) 30

31 B&V - 31 Discussion

32 5.0m 3.6m 1.4m Adsorption Adsorption Unit 7.5m Desorption Control Panel Adsorption Tower 3.3m & Recovery 2.3m Plant Layout Desorption & Recovery Unit Control Panel 32