The Development of Operational Tools for City-Wide Implementation of BNR in New York City. Sarah Galst, P.E. Hazen and Sawyer, P.C.

Transcription

1 The Development of Operational Tools for City-Wide Implementation of BNR in New York City Sarah Galst, P.E. Hazen and Sawyer, P.C. January 27, 2015

2 Outline Background to NYC Nitrogen Programs - East River - Jamaica Bay BNR Training - SOPs Lessons Learned - Case Studies - ph - DO - TSS Flow distribution Wet Weather

3 Background to NYC Nitrogen Concerns Long Island Sound Study - partnership between USEPA, NY, CT (1988) Water quality concerns Eutrophication Hypoxia - Nitrogen identified as causal agent

4 Background to NYC Nitrogen Concerns Reduction from 108,375 lb/d Phased approach to Nitrogen reduction to achieve an overall reduction in effluent TN of 59% to 44,325 lb/d Construction of BNR facilities for 4 wastewater treatment plants (WWTPs) on the Upper East River Wards Island Hunts Point Tallman Island Bowery Bay

5 4 Upper East River Plants Wards Island 275 mgd Hunts Point 200 mgd Tallman Island 80 mgd Bowery Bay 150 mgd

6 East River TMDL Step-downs 120, ,000 Combined East River Construction Bulge Time period Eff TN Limit lb/d Initial 108, ,000 Dec ,075 90,000 80,000 70,000 60,000 50,000 40,000 30,000 20,000 10, /1/2003 1/1/2004 1/1/2005 1/1/2006 1/1/2007 1/1/2008 1/1/2009 1/1/2010 1/1/2011 1/1/2012 Effluent Nitrogen (lbn/d) Consent Order Limit 1/1/2013 1/1/2014 1/1/2015 1/1/2016 1/1/2017 1/1/2018 Hunts Point WWTP Online Bowery Bay WWTP Online Wards Island WWTP Online Hunts Point Carbon Addition Tallman Island WWTP Online Carbon at TI, BB, WI July ,375 July ,275 Aug ,275 Jan ,325

7 Future East River TN Limits Step-down date Limit Stepdown UER Effluent TN Contingent Upon July , mg/l August , mg/l January , mg/l BNR operation of 3 UER WWTPs BNR Operation of all UER WWTPs, and carbon at one WWTP All BNR construction Complete AND Carbon addition at 4 UER WWTPs

8 Ongoing Nitrogen Removal Predicted and Observed Effluent Quality in the East River Effluent Nitrogen (lbn/d) 120, , ,000 90,000 80,000 70,000 60,000 50,000 40,000 30,000 20,000 10,000 0 Consent Order Limit Observed Effluent TN Estimated Avg Effluent, 12-Mo Rolling Avg 1/1/2003 7/1/2003 1/1/2004 7/1/2004 1/1/2005 7/1/2005 1/1/2006 7/1/2006 1/1/2007 7/1/2007 1/1/2008 7/1/2008 1/1/2009 7/1/2009 1/1/2010 7/1/2010 1/1/2011 7/1/2011 1/1/2012 7/1/2012 1/1/2013 7/1/2013 1/1/2014 7/1/2014 1/1/2015 7/1/2015 1/1/2016 Hunts Point WWTP Online 7/1/2016 Bowery Bay WWTP Online 1/1/2017 Wards Island WWTP Online 7/1/2017 1/1/2018 Tallman Island WWTP Online Hunts Point Carbon Addition Carbon at TI, BB, WI

9 Nitrogen Removal in Jamaica Bay Comprehensive Jamaica Bay Water Quality Plan Submitted October 2006 Nitrogen discharges from the four Jamaica Bay (26W, JA, CI, RK) contributes to marshland degradation $100 Million of BNR upgrades to reduce Nitrogen discharges

10 Jamaica Bay WWTPs 1 26 th Ward 85 mgd 2 Jamaica 100 mgd Coney Island 110 mgd Rockaway 45mgd

11 Implementation to Nitrogen Removal 26 th Ward (Level 3) and Jamaica (Level 2+) WWTPs ü Completed Level 2 BNR upgrades at 26W ü Completed Carbon addition to SCT ü Completed Jamaica WWTP BNR Operation 2014 ü Carbon to 26W and Jamaica in 2016 Future BNR upgrades at Rockaway and Coney Island (Level 1) ü Construction Completion 2019 and 2020

12 Jamaica Bay Total Nitrogen Limits Time period Consent Order Nitrogen Limits (lb/d) January 1, ,300 Starting November ,600 Starting January ,500 Starting October ,400 Starting July 2017 Starting July 2022 TBD TBD Future Nitrogen Limits for Jamaica Bay are performance based 95 th percentile of one-year of data

13 Jamaica Bay Performance Effluent TN Load (lb/day) 70,000 60,000 50,000 40,000 30,000 20,000 10,000 0 Jul-99 Jan-00 Jul-00 Jan-01 Jamaica Bay WWTP Effluent Total Nitrogen Loads Initial Bulge Permit Limit (49,500 lbs/day) Jul-01 Jan-02 Jul-02 Jan-03 Jul-03 Jan-04 Jul-04 Jan-05 Jul-05 Jan-06 Limit Stepdown 11/1/09 to 41,600 lbs/day Limit Stepdown 1/1/09 to 45,300 lbs/day Jul-06 Jan-07 Jul-07 Jan-08 Jul-08 Jan-09 Jul-09 Jan-10 Limit Stepdown 1/1/12 to 36,500 lbs/day Limit Stepdown 11/1/13 to 36,400 lbs/day Nov-14 Rolling Average 30,000 lbs/day Jul-10 Jan-11 Jul-11 Jan-12 Jul-12 Jan-13 Jul-13 Jan-14 Jul-14 Jan-15 Monthly Avg 12-Mo Rolling Avg

14 BNR Construction Completing Several construction projects have completed BNR operations ongoing Operators must now achieve BNR treatment

15 BNR Training Successful BNR operation requires new set of operational tools - SRT control - DO control - Alkalinity/pH control - Optimized flow splits - Wet weather management - Froth/scum removal Training sessions provide transition

16 Typical Training Outline i. New York Nitrogen Management Program ii. Plant Description and Recent Performance iii. Nitrification/Denitrification Fundamentals iv. BNR Implementation, Infrastructure, and Operational Aspects v. SOPs vi. BNR Lessons Learned NO 3 NO 2 NH 3 N 2

17 Aeration Tanks Zone flexibility Seasonal adjustments Flow distributions Operational Targets

18 Solids Inventory Control Primary Effluent Flow Distribution RAS WAS/SWAS

19 Wet Weather Operations Wet weather response to protect nitrifying biomass - Divert excess wet weather flow to downstream passes, achieving contact stabilization and reducing solids loading on FSTs Maintain solids inventory in the upfront passes, essentially parking solids for temporary storage by limiting the PE flow through those passes.

20 Typical Flow distribution PASS PE 10% A RAS MLSS 5000 mg/l B PE 30% MLSS 4000 mg/l PE 40% C MLSS 2500 mg/l D Effluent MLSS 2000 mg/l PE 20%

21 Storm flow solids parking PASS PE drop from 10% to 0% A RAS MLSS 5000 increase to 6000 B C PE Drop from 30% to 25% MLSS 4000 increase to 5000 MLSS 2500 increase to 3500 PE Drop from 40% to 25% D Effluent MLSS 2000 decrease to 1500 PE Increase from 20% to 50% Optimal Wet Weather PE flow distribution shown as 0:25:25:50

22 Aeration DO Control System DO Targets for Optimal operations Anoxic Zone DO<.5 mg/l Oxic Zone DO>2 mg/l Anoxic Zone DO<.5 mg/l

23 Alkalinity/pH Control Installed system Target ph Seasonal operations

24 Centrate Treatment Separate Centrate Treatment (SCT) operation in dedicated Aeration Tank Tank flexibility Instrumentation Seasonal Operations Recycle Centrate RAS Alkalinity Addition Alkalinity Addition Effluent Aerobic Fixed Anoxic Swing De-Ox ph meter

25 Froth Control Froth Hoods RAS Chlorination Polymer Surface Wasting - % wasting - Impact on SRT Surface Wasting Bell Weir Froth Hood Surface Wasting Polymer Addition

26 SOPs Plant Specific Poster - PE flow distributions - AEMLSS/Solids Inventory targets - Aerobic/anoxic configurations - SCT Operation Wet weather operation Froth Control DO targets Alkalinity/pH targets

27 On-site Assistance 6-12 month long sampling program - Profiles Nitrogen Solids DO ph - Evaluation of Instrumentation - Process Optimization - Control strategy Adjustment Provide plant process staff with important information Are SOPs being followed? Are any changes needed to SOPs for optimized future strategies? Assist with achieving overall acceptance by the regulator

28 Lessons Learned - Wards Island WWTP

29 Wards Island Low ph Conditions Routine ph profiles revealed low ph conditions in the Separate Centrate Treatment (SCT) Tank Nitrogen 7 Alkalinity profiles showed a leveling off in NH 3 -N concentrations at lower ph, indicating nitrification inhibition Centrate addition point Nitorgen Contentration (mgn/l) SCT Aeration Tank Profile (No Caustic Addition) NH 3 -N Concentrations Level Off with Drop in ph Mid End Mid End Head Mid End Mid End Mid End Head Mid End ph Anoxic Zone Aerobic Zone Aerobic Zone Anoxic Zone Aerobic Zone Aerobic Zone Pass A Pass B Pass C Pass D NH3-N ph 29

30 Wards Island Low ph Conditions Plant operators alerted to the low ph conditions in the SCT Tank and the resulting poor nitrification Recommended to add supplemental alkalinity Resulting Nitrogen profile Improved nitrification performance Nitorgen Contentration (mgn/l) Centrate addition 60 point Mid End Mid End Head Mid End Mid End Mid End Head Mid End Anoxic Zone SCT Aeration Tank Profile (With Caustic Addition) Steady decrease in NH3-N Concentrations Aerobic Zone Aerobic Zone Anoxic Zone Aerobic Zone Aerobic Zone ph Pass A Pass B Pass C Pass D 30 NH3-N ph

31 Lessons Learned - Battery E at the Wards Island WWTP

32 Battery E DO Impact on Nitrification Accepted DO Concentrations Produce Higher Than Expected Ammonia 14 Per. Mov. Avg. (Eff TN mg/l) 14 Per. Mov. Avg. (Eff NH 3 mg/l) 7 Per. Mov. Avg. (DO) Nitrogen Concentrations (mgn/l) Effluent Ammonia Concentrations as high as 6-7 mg/l with DO Concentrations at SOP suggestion of 2.0 mg/l Effluent Ammonia Concentrations dropped to 1 mgn/l with DO Concentrations around 4.0 mg/l Dissolved Oxygen Concentrations (mg/l) /15/2011 5/29/2011 6/12/2011 6/26/2011 7/10/2011 7/24/

33 Battery E DO Impact on Nitrification Accepted DO Concentrations Produce Higher Than Expected Ammonia 14 Per. Mov. Avg. (Eff TN mg/l) 14 Per. Mov. Avg. (Eff NH 3 mg/l) 7 Per. Mov. Avg. (DO) Nitrogen Concentrations (mgn/l) Effluent Ammonia Concentrations as high as 6-7 mg/l with DO Concentrations at SOP suggestion of 2.0 mg/l Effluent Ammonia Concentrations dropped to 1 mgn/l with DO Concentrations around 4.0 mg/l Dissolved Oxygen Concentrations (mg/l) DO Concentrations increased to 4.0 mg/l /15/2011 5/29/2011 6/12/2011 6/26/2011 7/10/2011 7/24/

34 Battery E DO Impact on Nitrification Accepted DO Concentrations Produce Higher Than Expected Ammonia 14 Per. Mov. Avg. (Eff TN mg/l) 14 Per. Mov. Avg. (Eff NH 3 mg/l) 7 Per. Mov. Avg. (DO) Nitrogen Concentrations (mgn/l) Effluent Ammonia Concentrations as high as 6-7 mg/l with DO Concentrations at SOP suggestion of 2.0 mg/l Effluent Ammonia Concentrations dropped to 1 mgn/l with DO Concentrations around 4.0 mg/l Dissolved Oxygen Concentrations (mg/l) /15/2011 5/29/2011 6/12/2011 6/26/2011 7/10/2011 7/24/

35 Lessons Learned - Bowery Bay WWTP

36 Bowery Bay Solids Profiles Aeration Tank Total Suspended Solids (TSS) Profiles are conducted for many reasons: Monitor solids inventory - Is the target solids inventory available? Determine actual Primary Effluent (PE) flow distribution when flow measurement not available - Do they line up with target PE flow splits? Quantify plant response to wet weather - How does flow distribution change? - Are solids maintained or washed out? 36

37 Bowery Bay PE Flow Distribution During Wet Weather, a temporary modified flow distribution is needed to avoid solids washout from the process Shift flow downstream, preserve solids in upfront passes Recommended target Wet Weather PE flow distribution: 0/25/25/50 % to Pass A/B/C/D TSS profiles conducted by on-site assistance team during Wet Weather to ensure: Washout of biomass is not occurring Gate settings provide the desired PE distribution 37

38 Bowery Bay Wet Weather Flow Distribution Bowery Bay 150 MGD DDWF Max of 225 MGD through secondary treatment Results from Wet Weather day at BB, plant flows averaged 300 MGD TSS profiles showed solids were preserved in early passes; gate settings matched target flow splits 8,000 Pass A Pass B Pass C Pass D 7,000 GOAL FLOW SPLIT 0% 25% 25% 50% NB Avg Flow Split 0% 29% 27% 44% Total Suspended Solids, mg/l 6,000 5,000 4,000 3,000 2,000 1,000 SB Avg Flow Split 0% 19% 27% 55% NB Avg AEMLSS 6,700 3,000 2,000 1,300 SB Avg AEMLSS 7,000 4,200 2,500 1,500 AT1 AT2 AT3 AT4 AT5 AT6 AT7 AT8 AT9 SB NB 38 0 Pass A Pass B Pass C Pass D

39 Bowery Bay Solids Profiles TSS profiles on all North Aeration Tanks AT8 exhibited strange profile low solids in A/B, but high solids in C? AT8 PE sluice gate in Pass A open 100% - causing backflow of RAS into PE channel Passes A and C both fed from same channel RAS escaping into the channel through A gates, and entering Pass C 3,500 Total Suspended Solids, mg/l 3,000 2,500 2,000 1,500 1, AT7 AT8 AT Pass A Pass B Pass C Pass D

40 Bowery Bay Solids Profiles Backflow also observed from head of Pass B to the end of Pass A with this hydraulic condition Low solids along with a low HRT in the early Passes of AT8 had a significant impact on nitrification performance Nitrogen Concentration, mgn/l Back mixing evident Bowery Bay Aeration Tank 8 - Nitrogen Profile 2,500 2,000 1,500 1, Total Suspended Solids, mg/l 0 A An Mid A An End A Ae Mid A Ae end B An Mid B An End B Ae Mid B Ae end C An Mid C An End C Ae Mid C Ae end D An Mid D An End D Ae Mid D Ae end 0 40 NH3 NO3 NO2 TSS Anoxic Zone

41 Bowery Bay Solids Profiles Plant alerted to flow conditions Plant adjusted the PE gate settings to Pass A Solids distribution and PE flow splits returned to the recommended operating range 4,500 Total Suspended Solids, mg/l 4,000 3,500 3,000 2,500 2,000 1,500 AT7 AT8 AT9 1, Pass A Pass B Pass C Pass D

42 Conclusions BNR training provides the information necessary to successfully transition from a traditional BOD and TSS removal facility to a step-feed BNR facility Development of SOPs and on-site assistance allows for optimization of processes and adjustment of control strategies BNR upgrades essentially completed! - No instances of non-compliance Carbon addition started in 2014, continuing through 2016

43 Acknowledgements - New York City Department of Environmental Protection Keith Mahoney Laura Grieco - Hazen and Sawyer, P.C. Michael Lynch, Robert D. Smith Paul A. Pitt, Ph.D.

44 Questions?