Membrane Thickening Aerobic Digestion Processes - PNCWA
Membrane Thickening AerobicDigestion Processes2012 PNCWA ConferenceBryen Woo, PE
DIGESTION EXPERTISE WEFTEC 1997-2001AEROBICDIGESTIONWORKSHOPVOL III 1999AEROBICDIGESTIONWORKSHOPFine Tuningthe ControlledAerobic DigestionProcessVOL I 1997The ChallengeOf MeetingClass BWhile DigestingThicker Sludges recognized as the industry leader in aerobicdigestion and thickening at high solidsconcentrationsCD-ROM
Membrane Thickening Digestion Aerobic digestion process using a Flat Plate Membrane UnitIdeal for:Facilities obligated to meetstringent nutrient dischargelimits, specifically totalnitrogen and phosphorusDecentralized facilities orReduced operations staffClass B Applications
How Does Membrane Thickening Work? How Does Sludge Get Thickened With a Membrane? A membrane thickening (MBT) submerged unit is used tocreate a physical barrier across which to extract clear waterfrom sludge. Air diffuser incorporated on the lower part of the cassette.
Air Scouring
Membrane Thickener Key Ingredients Key Ingredients Flux Rate of filtration per unit area of membrane material. Since thickeningis typically three times more than an MBR process, flux rates are significantlylower MBR flux @ 20 C 17.2 gfd vs MBT flux @ 20 C 5.1 gfd Transmembrane Pressure (TMP) The pressure across the membraneduring filtration. Typical TMP at design flux rates 0.5 to 0.75 psig Maximum TMP 3.0 psig Air Scour Air flow required to scour membranes to prevent fouling Biofilm Complex dynamic of microorganisms. The interdependencybetween biological process conditions and membrane filtration performancethrough a biofilm is termed BioHydraulics
The Importance of Biofilm Biofilm Basics YOU DON’T GET TO CHOOSE: All submerged membranes have a biofilm.As soon as filtration starts and biological solids are brought to themembrane surface, biofilm formation occurs. Benefits Biofilm serves as a secondary dynamic filter and represents a changing to filtrateflow. Create a dense secondary membrane that can allow for enhanced nutrient removaland degradation of refractory organics. Biofilm management is the key to operating a successful membranethickening system.
Biofilm gh TMPTMPIncreasedTMP
Biofilm ConditionsGOODBAD
Membrane Thickener Facts Membrane Thickener Flat Plate Membrane Thickener Facts PE membrane ultrasonically welded to ABS plate. Nominal pore size 0.4 micron, effective pore size 0.1 micron Effective air filtration area 8.6 ft2 per cartridge MBT Design flux 5 gfd @ 20 C MBT Cross flow velocity is 2.25 ft / sec
Minimum Maintenance Requirements Automated Diffuser Cleaning, approximately 30 min/day Membrane Relax, approximately 1 min/10 min Chemical Cleaning, in-situ cleaning every 6 months, approximately 2hour durationNO NEED TO DRAIN TANKS OR TAKE OUT OF SERVICE FORCHEMICAL CLEANING.
Why use a Membrane Thickening ProcessOperational Benefits of Membrane Thickening1. Improved and Reliable ThickeningPolymerandDecanting
Why use a Membrane Thickening ProcessOperational Benefits of Membrane ThickeningSO Polymer andDecantingReduced Operator Attention
Why use a Membrane Thickening ProcessEconomic Benefits of Membrane Thickening2. Reduced FootprintDigestion withMembrane ThickeningTraditional Digester Class B Stabilization in a Reduced volume Reduced Tanks Sizes and Ideal for Retrofits Less air requirements/energy usage.
Why use a Membrane Thickening ProcessProcess Benefits of Membrane Thickening3.Produces a High Quality Permeate that features: Minimal Total N and P without chemical addition Reuse quality that can be recycled to head of plant orsent to disinfection Protects effluent quality of BNR Process
Aerobic Digestion Processes vs Activatedsludge processesAerobic Digestion is a biological process similar toActivated Sludge.Activated Sludge GrowthAerobic Digestion Decay
Aerobic Digestion Processes vs Activatedsludge processesPractical Approach To Help Understand theDifference!Activated SludgeAerobic Digestion
Aerobic Digestion Chemistry1. Digestion:C5H7NO2 5O2 4CO2 H2O (NH4HCO3)BiomassAmmonium Carbonate2. Nitrification:NH4 2O2 H2O 2H NO3AmmoniaAcid Nitrate3. Digestion with Nitrification:C5H7NO2 7O2 5CO2 3H2O HNO3BiomassNitric Acid
Aerobic Digestion Chemistry4. Digestion with Nitrification:C5H7NO2 7O2 5CO2 3H2O HNO3BiomassNitric Acid5. Denitrification:C5H7NO2 4NO3- H2O NH4 5HCO3- 2N2Biomass NitrateAmmoniaN GasAlkalinity6. Complete Nitrification / Denitrification:C5H7NO2 5.75O2 5CO2 3.5H2O 0.5N2BiomassN Gas
Membrane Thickening Aerobic DigestionProcessDigestSludg eate
Case StudiesCase Studies Membrane Thickening AerobicDigestion Processes
Dundee WWTP, MichiganFirst U.S. Installation
Dundee WWTP, MichiganCommissioned:Liquid Process:MBT Size:Solid Conc.:Chemical Cleaning:2005MBR (1.2 MGD)800 plates3%-5.25%2-3 / year (scheduled)
Dundee WWTP, MichiganEngineer: ArcadisDigester#2"History:"Digester #1"MBTObjective was to reduce the haulingto 2 times per year. Tanks aredesigned to store 180 days at 3%solids.Operator friendly when comparedto other systems.
Dundee WWTP, MichiganThickening PerformanceSep & Oct 2005 Operation654WASMBT ThickenerDigester #1Digester #2% solids 3210Date
Dundee WWTP, MichiganSeptember 2005 to June 2008 DataSustainable Permeate mg/lmg/lmg/lmg/lmg/l
Dundee WWTP, MichiganSludge Hauling Cost SummaryYearsGallons HauledDry TonsYearly Cost2004 (0.6 MGD)248,885 – Belt943,200 – Truck1,192,100 - Total22.67 – Belt99.39 – Truck122.06 - Total 16,850 – Belt 30,088 – Truck 46,938 - Total2005 (1.2 MGD)MBT operational for2nd half of year only572,400 – Belt432,000 – MBT1,004,400 - Total55.62 – Belt47.55 – MBT103.17 - Total 39,135 – Belt 14,623 – MBT 53,758 – Total2006887,400 - MBT130.48 – MBT* 32,739 - MBTBelt press was needed for years 2003 -05 due to lack of storagespace.Sludge Hauling costs for first full year of operation of MBT in2006 was 32,739 which is cheaper than the last 5 years* Sludge Production minimized due to N/DN
McFarland Creek WWTP, OhioEngineer: CT ConsultantsTwo Stage Membrane Thickening AerobicDigestion Process
McFarland Creek WWTP, OhioMembrane Units Installed Directly Inside theDigesters
McFarland Creek WWTP, OhioCommissioned:Waste Type:Liquid Process:MBT Size:Solids Conc.:2005MunicipalMBR (1.8 MGD)400 plates3.5%-5.5%
McFarland Creek WWTP, Ohio60,00050,000TSS (mg/L)Thickening tank /2511/141/32/22DateThickening tank 2Membrane thickening at McFarland CreekWWTP was able to thicken up to 5% solids.
McFarland Creek WWTP, OhioMcFarland Creek WWTP Improved Dewatering OperationsAnnual BFP run time w/o PAD -K8,736 hoursAnnual BFP run time with PAD -K3,744 hoursReduction BFP run time57.14%MORE EFFICIENCY MEANS BETTER RESULTS .41% Reduction in CUBIC YARDS PRODUCED36.5% Reduction in DRY TONS PRODUCED41% Cost Reduction in POLYMER41% Cost Saving in SLUDGE DISPOSAL
Woodside WWTP, New YorkBiological Process: Concentric Circular PlantGOAL: Reduce Number of Sludge Hauling TripsLess gallons to haul per year:Sludge hauling reduction625,783 gal.Savings per year 59,449ROI of 2.57 years based solely on hauling
Cayce WWTP, South CarolinaEngineer: American Engineering ConsultantsMembrane Thickening Digestion Following a CarrouselBiological Process: Coming To A Theatre Near YouCurrent Site8 MGD Cap.To be expanded to25 MGDMembraneThickeningDigestion selectedto protect BioPCarrousel Ditch
Cayce WWTP, South CarolinaPlant Layout at 25 MGDBioP CarrouselSolids Handling
Cayce WWTP, South CarolinaCayce WWTP Carrousel MD ProcessStart-up Plant Flow Intermediate Plant Flow Design Influent Plant Flow WAS concentration Design digestion SRT Membranemodules inSeries8 MGD12 MGD25 MGD 10,000 mg/l20 days
Cayce WWTP, South Carolina"Benefits"Eliminated construction of thickener building."Reduced number and size of digesters by operating at 4% TS."Provided flexibility for a gradual flow increase."Reduced O&M costs by eliminating use of polymer for thickening."Reduced O&M costs due to less aeration / energy needs."Reduced O&M costs due to less supervision needs.SAFEGUARD HIGH QUALITY BIO-P CARROUSEL EFFLUENT
ConclusionsMEMBRANE THICKENING AEROBIC DIGESTION PROCESSES BRING:ECONOMIC VALUE: Reduced Tank Sizes and Ideal for RetrofitsSavings on Energy, Disposal, Chemical, and Concrete CostsPROCESS VALUE: Class B StabilizationReuse Quality Permeate with Low Total N and POdor ControlIncreased Solids Storage Capacity in existing or new tanksOPERATIONAL VALUE: Reduced Operator AttentionThickening Without PolymersNo Attention to Decanting
Any Questions?ANY QUESTIONS?
Thank YouTHAT’S ALL FOLKS!Bryen Woo, PEAerobic Digestion/Aeration ProductManager512-652-5818Bryen.woo@ovivowater.com
Aerobic Digestion is a biological process similar to Activated Sludge. Activated Sludge Growth Aerobic Digestion Decay. Aerobic Digestion Processes vs Activated sludge processes Practical Approach To Help Understand the Difference! Activated Sludge Aerobic Digestion . Aerobic Digestion Chemistry 1. Digestion: C 5H 7NO 2 5O
Aerobic Digestion Process. Class B Of Meeting While Digesting Thicker Sludges The Challenge. VOL I 1997. WORKSHOP DIGESTION AEROBIC. CD-ROM recognized as the industry leader in aerobic digestion and thickening at high solids concentrations. Digestion Expertise. 4.
Thickened liquids are made by mixing a thickening powder with your usual drinks. There are different brands of thickening powder available but they all do the same thing. Thickening powders do not add extra calories or essential nutrients to your drinks. Thickening powders may cause choking and obstruction if swallowed dry, so make sure
(Aerobic Digestion) Stored Food Aerobic Digestion Endogenous Stabilization High CRT allows for the microbes to feed off of the cell contents of other dying/decaying microbes under digestion. 20 to 25% by weight inert solids Fine inorganic solids, organic solids, and cell components that are not degradable Not all solids can be digested Aerobic .
14.1 Principles of starch digestion In all animals, digestion occurs via a combination of microbial and enzymic digestion. Microbial digestion relies on enzymes produced by microbes whereas the host’s digestion system relies on endogenous enzymes secreted into the digestive tract. Microbes possess a far wider range of
Aerobic digestion of waste is the natural biological degradation and purification process in an oxygen-rich environment, whereas anaerobic digestion is accomplished without oxygen in a closed system. Aerobic digestion technologies have been widely applied in organics wastewater treatment due to high degree of .
and aerobic digester is optimized for effective nitrogen removal. 12minutes aerobic and 12 minutes anoxic phase gave better nitrogen removal compared to all the cycles. Over all the aerobic digester gave about 92% ammonia removal, 70% VS destruction and 70% COD removal. The oxygen uptake rates (OUR's) in the aerobic digester are measured
MOP 11 Operation of Municipal WWTP Volume III: Solids Processes Chapter 31: Aerobic Digestion Author: Elena Bailey. Digestion Expertise 5 MOP No. 8 5th Ed., 2009 Design of Municipal WWTPs Volume III: Solids Processing and Management .
Architectural Drafting Line Work Arrowheads are drawn freehand. The length of an arrowhead is the same dimension used for the height of lettering. The proportion of the length of the arrowhead to the width is 3:1 respectively. Arrowheads can be either open, closed, solid, or the traditional slash as shown. Other types of symbols can be used in place of the arrowhead or slash. These include .
