Ohio Water Environment Association Present and Future Technologies for Nutrient Removal

Transcription

1 Ohio Water Environment Association Present and Future Technologies for Nutrient Removal James L Barnard, Ph.D., D.Ing. h.c. BCEE, WEF Fellow, Dist. MASCE

2 Contents Problems relating to Nutrients Wastewater as Resource Basics of present nutrient removal and recovery Future developments Nutrient Roadmap

3 Microcystis Poisoning Dr. Anthony Turton, Keynote Address CSIR RSA November 18, 2008

4 Fishkill Ocean life on the brink of mass extinctions overfishing, excessive nutrients causing dead zones. News Daily Posted 2011/06/21 at 5:50 am EDT Photo by Gerald Simons Lee Kuan Yew Water Prize 2011

5 Olympic Sailing Craft in Algae at Qingdao

6 Foreign Policy May/June 2011 As the new year begins, the price of wheat is setting an all-time high in the United Kingdom. Food riots are spreading across Algeria. Russia is importing grain to sustain its cattle herds until spring grazing begins. India is wrestling with an 18-percent annual food inflation rate, sparking protests. China is looking abroad for potentially massive quantities of wheat and corn. The Mexican government is buying corn futures to avoid unmanageable tortilla price rises. the U.N. Food and Agricultural organization announced that its food price index for December hit an all-time high. Increased cost of Fertilizer

7 Possible Resource Recovery Cooling Towers Potable Water Used Water Urine Separation BNR Protein Recovery Gas Power Irrigation Heat Recovery Fertilizer Composting Pelletization Incineration

8 Comparative Energy Requirement Energy used for B&V - 8 kwh/c/a BNR Wastewater Treatment 40 Average pumping for 21 treatment plants 69 Switching one lamp to low energy fixtures (Saving/lamp/a) 102 Pumping water from Missouri River to Kansas City 60 Pumping water from north to south of California 355 Desalination of brackish water 200 Desalination of seawater 525 Office lights for one person at 12 hours per day 1,750 Household per person (2 persons) 9,600

9 Heat recovery from effluent Community College

10 The Nitrogen Cycle Precipitation Nitrogen in atmosphere (N 2 ) Plants Nitrogen-fixing bacteria in root nodules of legumes Nitrogen-fixing soil bacteria Ammonification Decomposers (aerobic and anaerobic bacteria and fungi) Assimilation Nitrification Nitrifying bacteria Denitrifying bacteria Nitrates (NO 3- ) Ammonium (NH 4 +) Nitrites (NO 2 -) Nitrifying bacteria

11 Nitrogen removal

12 The Nitrogen Cycle 4.77gC/g N 1.7 go/gn H-B Process 2.8 go/gn N/DN Uses O 2 for NN and Carbon for DN Can be reduced if not going all the way to Nitrate Anammox bacteria can eliminate carbon while reducing oxygen to 60% Nitrification by slow growing temperature sensitive autotrophs

13 What is denitrification Conversion of Nitrates to Nitrogen gas Nitrogen gas N2 Sugar C 12 H 22 O 11 Bacterium Carbon Dioxide + Water CO 2 + H 2 O Oxygen O 2 Nitrates NO 3

14 Suspended growth systems MLE Bardenpho Channel systems MBR SBR Granular activated sludge

15 Single Stage Denitrification MBE (MLE) ANOXIC AEROBIC CLARIFIER Q MIXED LIQUOR RECYCLE 4Q NH 3 < 0.5 mg/l NOx < 6 mg/l TN < 8 mg/l RETURN ACTIVATED SLUDGE WASTE SLUDGE

16 Bardenpho Process Optional Carbon Settled Used Water N Gas Methanol Optional N Gas Air P Air Effluent Anaerobic Anoxic Aerobic Anoxic Aerobic P Waste Solids with Phosphate Effluent Ammonia N = 0.5 mg/l TN < 3 mg/l TP < 1 mg/l

17 The future in BNR Membrane Tank Anaerobic Anoxic Aerobic Post Anoxic Water Sludge

18 Cauley Creek Membrane BNR Bioreactor DeOx/DeNit Anaerobic Anoxic Aerobic

19 Vienna plant uses SND - Saves energy

20 Fixed Film Processes Nitrification Biological Aerated Filter (Biofor, Biostyr) MBBR Trickling Filter Fluidized Bed Denitrification Biological Filter (Biofor, Biostyr) MBBR Deep Bed Sand Filter (Tetra) Upflow Fluidized Bed (Envirex)

21 Multi-stage N/DN Carbon Source Carbon Nitrification Denitrification Hi Rate AS CEPT BAF TF MBBR BAF Fluidized bed Denite Filter MBBR BAF

22 Add on N/DN Systems Methanol High Rate Activated Sludge BAF Tetra Sand Filter

23 Nitrogen recovery Only viable if less energy is used than fixing Nitrogen from the atmosphere Can only be considered from high concentration return streams Cambi as high as 2,000 mg/l Methods used Ion Exchange Stripping and capture of ammonia Haber-Bosch process uses about 12 kwh/kg nitrogen fertilizer Anammox Demon Anitamox make recovery even less viable `

24 Clinoptilolite Ion Exchange for Ammonia Recovery

25 Ammonia Stripping and capture from return streams - Oslo Norway From Evans 2009 HNO 3 used for absorption

26 Lower portion of adsorption column Final Product 54% NH 4 NO 3 90% nitrogen removal

27 0 gc/g N 1.7 go/gn

28 Phosphorus removal Options Biological or chemical

29 Chemical Phosphorus Removal Add chemical to precipitate soluble phosphorus Alum, ferric chloride, ferrous chloride, magnesium hydroxide, polyaluminum chloride, etc. Multiple dosing locations Increases sludge production, consumes alkalinity Al 3+ /OP Ratio Alum Dosage vs. Target Effluent Phosphorus Effluent OP, mg/l Median Literature Dosage Influent PC Aeration RAS SC Tertiary P removal Filters Effluent Raw PS WAS

30 Benefits of Combined systems It is practically possible to reduce soluble phosphorus to levels as low as 0.07 to 1.1 mg/l biological means only in phosphorus removal plants Further polishing with chemicals in tertiary treatment can reduce this to an effluent total P of less than 0.05 mg/l Durham, OR used 175 mg/l of Alum when operating chemical only, added to primary, aeration and post treatment Reduced to 25 mg/l when applying biological plus chemical polishing to get 0.07 mg/l as P Pinery Water achieves LT 0.03 mg/l TP with a biological/chemical sequence

31 Microbiology

32 Bio-P Organisms Store PHB and Release P in the Anaerobic Zone RbCOD Influent Facultative heterotrophs Influent Volatile Fatty Acids PHB Energy Poly-P Phosphate No dissolved oxygen or nitrates VFA from outside source or MLSS fermention These are obligate aerobes. They can store but not process 3/12

33 PHB Poly-P Electron microscope Poly stains black, PHB stains white Poly-P

34 Bio-P Organisms Oxidize PHB and Remove P in the Aerobic Zone Poly-P Phosphate Stored in anaerobic zone. Consumed in aeration basin providing energy for storage of phosphorus Energy PHB Oxygen (Nitrate) Phosphorus taken up to <0.1 mg/l Carbon Dioxide +H 2 O

35 Poly-phosphate stored in the aerobic zone. Phosphorus is removed with the WAS Poly-P

36 Biological Phosphorus Removal Fuhs & Chen, 1975

37 Typical Flow sheets When using SND much simpler process flow sheets are possible

38 rbcod/p ratio VFA and rbcod Requirements for P Removal At this point there is no VFA VIP McDowell Creek Durham These plants are getting fantastic results With Fermenter Eagle s Point Reedy Creek SC This line is used in BNR models 5.0 w/o fermenter At this point all rbcod is VFA Fraction of rbcod that is VFA

39 Fermenters

40 Static Fermenter Primary tank Anoxic Grimstad Norway anaerobic VFA to anaerobic zone VFA Oversized Thickener retain sludge for 6 to 8 days to digesters Westbank BC

41 Primary Anaerob Anoxic 1 Anoxic 2 Anoxic 3 Aerobic 1 Aerobic 2 Aerobic 3 Phosphorus mg/l Westbank WWTP Primary Anaerob Anoxic 1 Anoxic 2 Anoxic 3 Aerobic 1 Aerobic 2 Aerobic Bioreactor Profile Phosphorus by Zone Note P uptake in Anoxic Zone 08/06/08

42 Unconventional Flow-sheets

43 Bio-P through Operations St. Cloud, MN(turning the air down in the first pass) Effluent Total P (mg/l) /1/02 4/11/02 7/20/02 10/28/02 2/5/03 5/16/03 8/24/03 12/2/03 3/11/04 6/19/04 9/27/04 1/5/05 4/15/05 7/24/05 11/1/05 2/9/06 5/20/06 8/28/06 12/6/06 3/16/07 6/24/07 10/2/07 1/10/08 4/19/08 7/28/08 11/5/08 Total P 30-day Moving Avg (Total P)

44 Fermentation of Secondary Sludge Influent Wastewater Aerated Settling Effluent Sludge partially settled in this zone and fermented, providing VFA Lime Stripper Anaerobic Anaerobic Anoxic Return Biomass Lime Sludge Wasted Biomass Influent ON OFF Influent Wastewater Anaerobic Changed from Pho-strip to this Aerated Settling Effluent RAS Pinery Water CO RAS Wasted Biomass Return Biomass Stripper Fermenting portion of RAS Truckee Meadows NV

45 Metric Tons Total P Million Gallons Flow EBPR Operation at Kalispell, MT City of Kalispell WWTP Yearly Phosphorus Loading to Flathead Lake Flow Trendline Phosphate detergent ban; alum addition BNR Plant on-line Improved D.O. Improved D.O. Control Metric Tons Total P Million Gallons Flow Linear (Million Gallons Flow) From Joni Emrick

46 Future Roadmap Where are we and where would we like to be

47 Lo-Tech Option Biogas to vent or use? Anaerobic Zone Aerobic Nitrifying treatment (Rock Media TF or other?) Flow forced through settled sludge by baffles High void-space rock media growing methanotrophic and other denitrifying biomass biofilm Recycle Pump with high DO + nitrate rich effluent (Bio-gas powered?!)

48 Hi-Tech Option Biogas Gas Generator/Flare UASB? MBB R Air A-recycle Blower Methanotrophic Denitrification using Biofilm Reactor (Anoxic MBBR or SAF)

49 McCarty fluidized bed membrane reactor

50 Anaerobic Fluidized Membrane Bioreactor (AFMBR)

51 Concerns Since most all the carbon is removed how to remove nutrients Utilize methane remaining in the effluent of the anaerobic process Convert to methanol and use for denitrification Use chemicals for phosphorus removal Alternatively use dedicated Ion Exchange for nitrogen and phosphorus removal with recovery of the nutrients

52 The Ultimate in SND Granular activated sludge SBRs with feed during decant, leading to SND and P removal

53 Nereda Technology Nereda Websitehttp://

54 Granular activated sludge Dublin 160 mgd plant uses same technology

55 Epe - Netherlands

56 Present Dublin Plant

57 Fill during decant

58 Fill during decant

59 Fill during decant

60 Fill during decant

61 SBR Operation Four basins operated in series all a the same level with fixed weirs Two basins aerated at any time One basin in sedimentation mode One basin in fill/decant. Flow automatically goes where valves are open for decanting Continuous flow Black & Veatch design/operating a plant treating a maximum flow of 260 mgd Very good settling sludge SVI 60 ml/g Could be operated to produce granular sludge.

62 Anammox for side-stream and main stream treatment

63 Return Stream Characteristics Temperature is high, C Ammonia concentration is high Typically mg/l NH4 N Higher concentrations for high solids digesters Low alkalinity Typical side=stream contains 50% alkalinity needed for nitrification of the ammonia ~3.5 mg Alkalinity as CaCO3/mg NH4 N Relatively low BOD (or COD) Recycle nitrogen constitutes 15 25% of nitrogen in the influent

64 0 gc/g N 1.7 go/gn

65 Anammox Physiology Anammox bacteria: Form biofilms and are often observed as suspended granules or on the surface of synthetic media. Are strictly anaerobic - reversibly inhibited by DO concentrations as low as 0.03 mg/l. Are inhibited by high NO 2-, but the threshold concentration is controversial. Have a remarkably slow growth rate. Reported doubling times are often as slow as 10 to 20 days.

66 Principle One Step Anammox Pacques presentation O 2 NH 3 NO 2 - N 2 NO - 3 NH NH NH O NO NH N NO 3 -

67 DEMON installation with cyclones for separating the Anammox granules for return to the process

68 Benefits of One Step ANAMMOX

69 B&V DESIGNING BLUE PLAINS WWTP FILTRATE TREATMENT FACILITY: DEMON PROCESS 69

70 BLUE PLAINS WWTP ANAMMOX: DEMON PROCESS Largest Anammox installation in the US designed to: Treat 1 MGD from liquid stream filtrate of sludge processing facility Removal rate: 12,400 kg-n/day Schedule: Design to be completed by late 2013 Final completion date in 2016 Estimate of Probable Construction Cost $ Million 70

71 Paques Plant - Rijn & IJsel Olburgen STW

72 CASE STUDY: Rijn & IJsel Olburgen STW Influent PHOSPAQ & ANAMMOX: UASB Effluent Reject water Flow 3, m³/d COD 2, kg/d TKN 1, kg/d PO4-P kg/d P.E. 47,500 10,000 Performance PHOSPAQ & ANAMMOX - effluent to STW: COD removal 50 % P removal 80 % TKN removal 90 % P.E. 8,600 Characteristics

73 Application of Anammox to Main-stream plant

74 For more information see Full-Plant Deammonification for Energy Positive Nitrogen Removal Joint WERF/WEF Webcast Thursday, November 7th, :00 3:00 pm Easter

75 Concept Energy efficient nitrogen removal Grow Anammox bacteria in side-stream at high temperature Waste surplus Anammox bacteria to main stream plant Use some selection process such as cyclones to concentrate Anammox bacteria from the waste activated sludge Feed back to main plant

76 Hi-rate A-B Process used in the Strass plant Plant is energy self-sufficient Second stage SND plant achieves denitrification with minimal energy input Side-stream DEMON process for energy efficient ammonia removal Successful experiments with main plant nitrogen removal enhancement with surplus DEMON organisms

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78 Future choices for Nutrient removal BNR with MBR with little chemicals Anaerobic membrane with IE for nutrient reduction and capture A-B process with chemicals for phosphorus removal but energy selfsufficient Granular activated sludge with little chemicals and possible phosphorus recovery

79 Membrane Bioreactor (MBR) Developed technology for N and P removal to very low levels Small footprint High quality effluent Replaces final clarifiers, filters and disinfection Disadvantage Energy intensive

80 Anaerobic membrane reactor Produces energy Very little sludge production Methane in solution could be used for denitrification Needs further polishing for low levels of N & P Phosphorus must be removed by chemicals thus no recovery

81 A-B process with SND Energy self-sufficient Established technology Normal footprint Applicable to existing high rate plants Needs further polishing for low levels of N Phosphorus removal by chemicals recovery expensive

82 Granular activated sludge New but proven technology Small footprint Reduced energy use Very simple operation low level of mechanical equipment SND a biological phosphorus removal Allow for phosphorus recovery Needs some filtration to reduce effluent TSS and nutrients

83 Phosphorus Recovery

84 Phosphorus is a limited resource US produces 25% of world resources Morocco has 6 times the deposits of the US Production limited to a few countries In less than 50 years high grade ore will run out At the present rate of consumption we may have enough for another 200 years The USA has stopped exporting phosphorus We cannot afford to use it once and waste it It is irreplaceable

85 Future Scenarios Towards global phosphorus security: A systems framework for phosphorus recovery and reuse options D. Cordell, A. Rosemarin, J.J. Schröder, A.L. Smit - Chemosphere 84 (2011)

86 North America Struvite Mg.NH 4.PO 4. 6 H 2 O Also recovers up to 20% of nitrogen

87 Incinerator Ash Deposit in dedicated site for future recovery

88 Summary Conventional BNR systems have served us well but uses energy and may have a large footprint Footprint becomes an issue for larger plants Energy and chemical use needs to be reduced Alternatives exist for most starting points Phosphorus recovery is serious

89 Personal Information James L. Barnard, Ph.D., D.Ing. hc., BCEE, WEF Fellow, Dist MASCE Global Practice and Technology Leader Black & Veatch Cambridge Terrace, Leawood KS Telephone Work Mobile

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