A Shortcut Nitrogen Removal Process for a Wisconsin WWTP

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2 A Shortcut Nitrogen Removal Process for a Wisconsin WWTP CSWEA 90 th Annual Meeting May 24, 2017 Autumn Fisher, City of Fond du Lac Randy Wirtz, Strand Associates, Inc. Jeremy Cramer, Donohue and Associates (previously City of Fond du Lac) Kevin Berg, Strand Associates, Inc.

3 Outline Fond du Lac Regional WTRRF Background City s Drivers for Sidestream Treatment Brief Sidestream Deammonification Background Process Analysis and Comparisons Technology Selection and Next steps

4 Fond du Lac Regional Wastewater Treatment & Resource Recovery Facility Design Population 128,000 Average Daily Flow 8 MGD

5 2016 WEF Utility of the Future Today

6 Nutrient Focus Areas at Fond du Lac Influent Phosphorus N Effluent Ammonia Sidestream Ammonia Sidestream Phosphorus Effluent Phosphorous P Influent Nitrogen Biosolids Phosphorus

7 Daily Ammonia Loading

8 Why Sidestream Deammonification? Help local business stay and grow Ability to continue taking in HSW Cost Avoidance Postpone/avoid construction of 4 th aeration basin Free up capacity Set up for Bio-P Save carbon to drive bio-p Less nitrate to manage Lower cost for ammonia removal energy savings

9 Process Modeling leading up to Bio-P Experience Modeling Confirms Operational Modifications of WTRRF (as constructed) are Not Reliable for Bio-P Modeling Used to Predict Benefit of Deammonification for Bio-P

10 Process Modeling (Energy/Air Usage) Modeling Used to Predict Deammonification Benefits for Airflow Reduction

11 Sidestream Deammonification (SSD) Process Analysis and Technology Comparisons

12 Conventional Nitrification / Denitrification Autotrophic Aerobic Environment 1 mol Nitrate (NO 3- ) Heterotrophic Anoxic Environment 25% O mg O 2 /mg N 40% Carbon 1.14 mg COD/mg N 75% O mg O 2 /mg N 1 mol Nitrite (NO 2- ) 1 mol Nitrite (NO 2- ) 60% Carbon 1.71 mg COD/ mg N 2.9 lb O 2 recovered (~60%) 3.6 lb alk recovered (~50%) 1 mol Ammonia (NH 3 /NH 4+ ) ½ mol Nitrogen Gas (N 2 )

13 Deammonification: Partial Nitritation/Anammox Autotrophic Aerobic Environment 0.57 mol Nitrite 35-40% O mg O 2 /mg N (NO 2- ) Autotrophic Anoxic Environment 1 mol Ammonia (NH 3 /NH 4+ ) AnAOB 0.44 mol Nitrogen Gas 0.11 mol Nitrate

14 Fond du Lac Solids Schematic MLSS Waste Primary Clarification Biological Treatment Final Clarification RAS SSD Reactor Sludge Storage Centrate Equalization Centrifuge Dewatering TPAD Anaerobic Digestion 212,000 gal 5 days/week; ~7 hrs/day

15 Current Weekly and Average Centrate Flows

16 SSD Design Flow Summary Parameter Current Conditions Future Design Conditions Weekly Centrate Vol. 756, ,000 Operating Day Centrate Volume (gpd) 151, ,000 Fully Equalized Centrate Flow (gpd) 108, ,000

17 SSD Design Centrate Characteristics (Through Planning) * * * * *

18 SSD Concerns with Centrate Characteristics Total Alkalinity to NH 4 : Desired 4:1 or higher Currently ~ 3.5:1 average Lower ratios limit efficiency Metal salt use may be a concern Optimal temperature around 30 o C; up to o C permissible. TPAD operation can have meso temps > 40 o C Post EQ temps can be > 40 o C Centrate TSS concentrations can vary widely main concern with heavier solids. PO 4 concentrations have increased main concerns with struvite and micronutrients availability

19 SSD Location Options (Existing Tankage) UNOX Tanks 2 150,000 gal each Centrate EQ Tanks 106,000 gal each Solids Processing & Centrate Production

20 Alterative #1: Use One Centrate EQ Tank for SSD Design HRT ~ 1 day Controls and Blowers in Adjacent Solids Bldg Likely lowest cost location/install SSD Reactor Centrate EQ (same as existing) Concerns Reduced EQ Could limit future HSW acceptance HRT too low for some technologies

21 Alterative #2: Use One UNOX Tank for SSD Design HRT ~ 1.5 days Controls and blowers in adjacent tanks or on deck Maintains both EQ tanks Higher cost but improved future flexibility SSD Reactor

22 SSD Equalization Requirements Optimal vs. Practical ~340,000 gal Required for Complete EQ

23 SSD Equalization Requirements Optimal vs. Practical ~340,000 gal Required for Complete EQ. If less than 340,000 gal provided, will require variable flows to SSD. System suppliers indicated minimum flow desired is about 50% of average. Lower flows (or no flow) can be accommodated but NH 4 removal efficiency will be impacted.

24 SSD Equalization Evaluations Maintain 2 Centrate EQ Tanks (212,000 gal) Full EQ during weekdays; lower feed rates required on weekends

25 SSD Equalization Evaluations 1 Centrate EQ Tank (106,000 gal) Several flow setpoints required; Low weekend flows.

26 Krueger ANITA- Mox World Water Works Demon (condea) Paques AnammoPaq Anammox Microscreen

27 Sidestream Deammonification System Supplier Comparison Project Costs Parameter Kruger ANITA Mox WWW Demon Paques AnammoPaq Installation Location HPO Basins or New HPO Basins or New HPO Basins, Centrate EQ, or New Project Cost (millions) $3.2 $4.5 $3.0 Net Annual O&M $19,000 $10,000 $11, Year Present Worth (millions) $3.4 $4.5 $3.2

28 Sidestream Deammonification System Supplier Comparison Process Guarantees Parameter Kruger ANITA Mox WWW Demon Paques AnammoPaq Ammonia Removal guarantee (No Alkalinity Addition) Present Worth Cost per Guaranteed Pound NH 4 Removed 80% 85% 83% $3,900 $5,000 $3,500

29 Sidestream Deammonification System Supplier Comparison Nonmonetary

30 Process Selection Form a team for evaluation and research FDL WTRRF Staff Superintendent Operations Leader Maintenance Foreman Research Coordinator Strand Associates Engineering Staff

31 Selection Areas focused on Best Fit Energy consumption Ease of operation Technical support # of Installations/volume treated Mainstream treatment Ability to sell media Manufacturer Paques - Reuse EQ tank for Reactor World Water Works Kruger - Option 2 Technology Annamox DEMON ANITA Mox Worldwide 35 (7 municipal) ANAMMOX systems, 9 PHOSPAQ systems, ~40 Installations 116 ASTRASEPARATORS 6 Sidestream None in US - Several in Netherlands York River (Virginia), DC Water (Washington, DC), Greeley, CO Installations Egan (Chicago), James River (Virginia), Durham (North Carolina) Mainstream Current research on bioaugmentation and cold temps 1 pilot (Strass - 3 years and temps as low as 10 C) Installations IFAS trials First RFP Budget $650, $1,114,000 Price Detailed RFP Price $830,000 (includes TPS solids removal) $1,475,000 $997,000 Process 200 mg/l NH4-N (equates to about 87%) without caustic >85% removal NH4-N, >75% removal Total N 75% NH4-N Removal and 65% Total N Removal Guarantee dosing Removal Efficiency Process Upflow suspended growth with large granules Sequencing batch reactor with hydrocylone granule separation Attached growth on plastic media Description Biomass Large granules are retained by equalization of upflow velocity Hydrocyclone separates anammox granules from AOB/NOB. Stainless steel screens attached to tank walls prevent media Retention and gravity settling Anammox returned to SBR, others are washed out from leaving tanks. Main Controlling DO (fine bubble mg/l DO), Nitrate-Nitrite, and ph controlled intermittent aeration dependent on ph (7.0), DO (0.3 - ph and DO ( mg/l) Water level controlled during tank Parameter & Ammonia conc. In-line sensors 0.5 mg/l), and time. design through placement of effluent screens Monitoring Feed Style Continuous flow Sequencing batch reactor (15 minutes of feed/hour for five hours Continous flow per cycle with 4 total reactor cycles/day) Water Level Water elevation controlled by effluent weir/opening Centrate is pumped to reactor from low level (10.4 feet) to high Tank water level established by elevation of effluent weir. elevation and is not variable level (12.75 feet) in 15 minute feed cycles, for 5 hours. Decanter lowers water level back to 10.4 feet (30 minute cycle) after a settling cycle (30 min). Existing EQ Tank Utilize one eq tank (114,000 gallons) for equalization, utilize Utilize both tanks (212,000 gallons) for equalization Utilize both tanks (212,000 gallons) for equalization Use one eq tank for Anammmox Reactor. Install TPS settling system near EQ tank Additional EQ Potential for future flow to require additional EQ. NO Needs? NO Reactor Tank South EQ tank Existing HPO basins east of the UV building Existing HPO basins eas of the UV Building Placement Reactor Volume 112,000 gallons (remove fillet in EQ tank to increase from 185,000 gallons 200,000 gallons 106k to 112k) Additional No - NO NO Tankage? Solids Separation? YES - ASTRA separator (sloped screen) YES - proposed to use EQ tank as a type of solids settler NO separation required using average TSS in proposal (will likely require TSS removal at peak concentrations) Solids Max Conc. TPS required to remove solids prior to anammox reactor 420 mg/l - proposed 420 mg/l - proposed / other literature has mentioned max of Process Narrative Centrate is stored in the north EQ tank to provide continous Centrate is stored in the EQ tanks to provide storage volume for Centrate is stored in the existing EQ tanks. The existing flow to the TPS settler and the Anammox reactor. Fillet will SBR operation. Centrate is pumped from the EQ tanks to the SBR centrate pumps pump stored centrate to the anammox be removed from EQ tank and water level will be increased to tank via a new centrate forcemain routed through some existing reactor using a new forcemain through the tunnel and the provide 114,000 gallons of equalization volume. Centrate is tunnels and the yard. The SBR system operates on a 5 hour yard. Continous flow is provided to the tank and effluent flow pumped continuously from the EQ tank to the TPS for solids feed/0.5 hr settle/0.5 decant cycle, repeated 4 times daily. During is controlled by the weir in the effluent box. Effluent removal. Centrate flows by gravity from the TPS to the the feed cycle, the feed pump operates for 15 minutes per hour, for discharges by gravity to a sewer drain manhole to the head ANAMMOX reactor, where ammonia is removed biologically. a total of 75 minutes feeding per cycle (5 hours total/day). During of the plant or potentially to the aeration basins. Deammonified efluent is then pumped to the headworks or the active period, the tank water level increases from 10.4 feet to to aeration basins. Solids are pulled from the TPS by feet. During the active period, the anammox bacteria underflow pumps and discharged to the sludge mixing tanks biologically remove ammonia. The hydrocyclone operates once per prior to digestion. active period to waste AOB/NOB and return anammox granules to the tank. After 5 hours active, all action stops and the tank contents settle for 0.5 hours. The decanter then starts and decants the tank from feet to 10.4 feet over a 0.5 period. The active period then begins again. Weekend Fill the EQ tank to capacity before end of operation on Friday. Fill the EQ tanks to capacity before end of operation on Friday. Fill the EQ tanks to capacity before end of operation on Operation Operate at reduced flow rate throughout the weekend Operate normally until centrate is used up (early morning on Friday. Operate at reduced flow until centrifuge operation on period. Conditions may indicated that extended centrifuge Sunday anticiapted). System enters standby mode when centrate is Monday. operating hours are beneficiail to the system. used up. Restart on Monday when enough centrate is avaiable to start the cycle. Reactor Mixing Aeration Only Two 9 HP Landia mixers on VFD Two 15 HP top entry mixers Aeration Type Annamox - Fine bubble diffusers Messner aeration panels (fine bubble thermoplastic polyurethane) Medium bubble - stainless steel header tube Aeration ANAMMOX SCFM 894 SCFM 874 SCFM (PROCESS AIR) Requirements Aeration ANAMMOX SCFM 1194 SCFM 1020 SCFM (PROCESS AIR Requirements Suggested Blower Annamox - 2 Duty + standby to 400 cfm 10 Duty + standby XX psig (60 HP) Duty + standby - 1,059 scfm psig (75 HP) Design psig (previous proposal indicated around 40 HP) Scope of Supply TPS settler; ANAMMOX reactor internals (settler, diffusers, Design and engineering; Decanter with 6-inch flange; 6-inch Decant 8510 cf media; 2 effluent screen assemblies; 1 medium Summary piping); ANAMMOX blowers (3 (2 duty 1 standby)); control valve; 52 aeration panels; SS drop pipes to supply aeration; bubble aeration system (SS headers, laterals, and hardware); Instruments (NH4, NO3, NO2, DO, ph, EC); 6000 gallons of Demon biomass separation system; Two biomass separation 2 top entry mixers; Four airlift pumps with flow distribution startup biomass; 1 week supervised installation, 2 weeks pumps (44 5 hp); One pressure sensor, two radar level assembly for scum/foam control(operated off blower air); 2 biological startup inlcuding travel and labor sensors (1 EQ and 1 Demon); two centrate feed pumps (450 gpm); PD blowers; Four Hach SC200 controllers with SST two PD blowers ( HP); two 9.0 HP landia mixers; enclosures; 1 HWL float; 1 ph probe; 1 DO probe; 2 Seed sludge; Demon Control program; 1 ph and DO probe; 1 NH4/NO3 probes; 1 thermal mass flow meter; 1 mag meter; conductivity probe; 1 air flow meter and 1 water flor meter; 4 Indoor Control panel with Allen Bradley controls trip/15 days start up services; analytical services for 20 samples for performance test; 3-4 months of remote monitoring services Additional Centrate Feed Pumps (may be able to use existing); 50% HPO Basin conversion; Centrate Forcemain through tunnel and HPO Basin Conversion, Centrate forcemain through tunnel Equipment NaOH Tote with Pump (peristaltic likely); Micronutrient Tote yard; Effluent piping and yard. Additional 1395 cf of media to meet 2035 load Required by FDL with Micronutrient Pump, Antifoam Solution Tote with One antifoam pump (peristaltic 1 gpd); Two Sludge pumps on separator; piping and renovations to the utility room in the basement of the solids processing building. Startup Services 2 weeks startup 4 trips/15 days - Initial startup shall include filling the unit with Field Services = 2 trips totaling 10 man-days. Training = 1 trip Provided water, adjustment of chemical feed systems, adjustment of any of 2 man days at start-up. Startup = three trips totalling 15 other pretreatment systems, electrical checkout of chemical and man-days. Performance testing = 1 trip totalling 5 man-days. pretreatment systms, and electrical checkout of control panels or Additional services billed at $1400/man-day plus T&L loops. Table 1 on page 26 of proposal details the parameters. expense Ongoing Technical Data review and technical support via phone/ up to months remote observation, weekly conference call. Additional Weekly conference call and remote data review and Assistance hrs/week for three months after startup. Specialist present support billed at $1,000/day plus expenses, minimum 2 day bill. consultation during start-up and testing. Provided during some of performance test. One year of tech support (under separate proposal) including phone/ (2 hrs/wk) following startup commissioning, two site visits of 2 days each (max 10h/d) including T&L, and summary reports. One year of tech support billed at $30,000. Performance Test Continous 14 day test. 24-hour composite sample gathered 30 day acceptance test operated by Owner. Sampling and analytical 30 day acceptance test. Contingent on sufficient alkalinty to at outlet of EQ tank and outlet of Anammox system. Owner support by Owner. Owner reponsible for all items as directed in maintain ph between 6.0 and 8.5 in process tanks, responsible for all sample gathering/prep and analysis. - O&M manual. Testing shall be conducted to maintain 1198 lb/day characteristics match Table 1 (page 19), no toxicity, average Acceptance based on average ammonia-n removal efficiency influent NH4-N ±10% and 1200 mg/l NH4-N; alkalinity to ammonia influent ammonia concentration shall be at least the design over 14 day period. System operated by Owner according to ratio 4.5; 7 day average demon temperature > 25C. concentration, NO SINGLE DAY AMMONIA CONCENTRATION O&M manuals. Nutrient dosage controlled by Paques. LESS THAN 95% OF THE DESIGN VALUE. Owner responible for Influent to system must match design parameters. full operationg of the system, sample collection, sample prep, License --- Licensed for treating max month of 1359 lb/day average load --- Biomass Value Estimated at 45,000/year. Depends on new installations and To be discussed - also interested in becoming a research market for biomass. facility for Kruger ideas. Media Required c.f Media Required c.f Nitrite toxicity? mg/l mg/l - had a major incident where anammox survived (at what levels?) nitrite concentration +200 mg/l Other toxicity Handles toxic shock well and recovers, polymer overdosing Polymer overdosing, AOB inhibition from dryer condenser water High nitrites - have done extensive testing showing how the issues? has effect on floculant and lowers O2 transfer, ph <6, Sulfides system responds to upsets/shutdowns/toxicity (LA County) (S2-) <1-5 Energy Input ~1 kwh/kg N removed 1.4 kwh/kg NH3-N removed ~ 1 kwh/kg NH3-N removed Maintenance Settle tank, drain supernatant, pump biomass out and hold, Clean/calibrate probes, decanter, cyclones, blowers Blowers, pumps, screens, mixers? clean blowers and sparger and put biomass back in tank Lab Testing Needs Verify in-line measurements, start up more extensive than NH3N, NO3N, NO2N, TSS, ph NH3N, NO3N, NO2N, ph daily maintenance Chemical Addition Possibly micronutrients, in some cases caustic, anti-foam Possibly micronutrients, unlikely to need alkalinity Biggest Concerns operation error, polymer overdose, communcation of good Operational changes being made to the system, issues with installs centrifuge operations, feed rates and ramp up and down - at Greeley, CO and Harvest Power - Requires forcemain to direct communication during troubleshooting - may require screen centrate to HPO basins - new technology coming with Demon upstream of the system most moving parts - sidewater depth limitations with decanter - modificaitons to equalization anticiapted to help with solids removal Best Features no forcemain - Simple operation based on DO control - Oldest Highest number of total installations in the world - have recently company working with anammox - Potential for future won major contracts in the US (7 in the US, 5 operating) - closely alignment with other Paques nutrient removal systems linked with Strass WWTP for research and development - No (sulfur/phosphorus) concerns with weekend shutdown, would just continue mixing without aeration - DEMON 2.0 is continuous feed - adjust SWD to accomodate loading Purchase seed Yes, contract agreement available Yes (paid per kg of seed sludge) back? (cost/lb) Licensing Fee No Yes, built into bid price and charge at a per kg removed rate No

32 Ovivo Paques AnammoPAQ

33 Selection 40+ Installations 215,000+ lbs-n/day cumulative treatment capacity ANAMMOPAQ Cumulative N load installed (lbs/d)

34 Quick Startup Selection

35 Selection Granular biomass with simplistic recovery 90-95% ammonia removal capacity Easy, continuous flow operation Lower cost

36 Summary Deammonification has benefits compared to conventional nitrification/denitrification Deammonification minimizes carbon use for nutrient removal, allowing increased emphasis on energy recovery Sidestreams from anaerobic processes are ideal candidates for deammonification Targeting sidestreams should be considered when analyzing nutrient removal alternatives Research on mainstream deammonification is advancing

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