BioBio--P RemovalP Removal-- Principles Principles ppand examples in MI and and examples in MI and elsewhereelsewhereelsewhereelsewhere

S. Joh Kang, Ph.D., P.E.S. Joh Kang, Ph.D., P.E.Tetra Tech IncTetra Tech IncTetra Tech, Inc.Tetra Tech, Inc.Ann Arbor, MI Ann Arbor, MI 20102010

Presentation OutlinePresentation OutlinePresentation OutlinePresentation Outline

Optimization of Chemicals and EnergyOptimization of Chemicals and EnergyOptimization of Chemicals and EnergyOptimization of Chemicals and EnergyBioBio--P Removal P Removal -- ReviewReviewE lE l MI d l hMI d l hExamples Examples –– MI and elsewhereMI and elsewhereEnergy : self sufficiency in the U.S. Energy : self sufficiency in the U.S. Summary Summary

Why are we talking Why are we talking about Bioabout Bio--P at MWEA?P at MWEA?about Bioabout Bio--P at MWEA?P at MWEA?

25 years track records in MI25 years track records in MI-- we we started it in the cold region started it in the cold region S t i bl tS t i bl t i i l lif li i l lif lSustainable systemSustainable system-- minimal life cycle minimal life cycle costs: costs: energy, chemicals, and sludgeenergy, chemicals, and sludge

Save Save jobsjobs

Reality CheckReality Check-- how much how much yyare we spending?are we spending?

At 5 MGD Plant in MIAt 5 MGD Plant in MI–– Chemicals $70,000Chemicals $70,000Chemicals $70,000Chemicals $70,000–– Chemical Sludge disposal $20,000Chemical Sludge disposal $20,000--

30,00030,000,,–– Electricity $200,000Electricity $200,000-- $250,000$250,000

7 7 –– 8 Cents /KW8 Cents /KW--Hr, averageHr, average// , g, gPeak demand chargePeak demand chargeYour mileage may varyYour mileage may vary

Phosphorus RemovalPhosphorus RemovalPhosphorus RemovalPhosphorus Removal

Phosphorus removal in a WWTP is Phosphorus removal in a WWTP is typically a combination of BPR and typically a combination of BPR and yp yyp yCPRCPRThe goal is to incorporate influent TPThe goal is to incorporate influent TPThe goal is to incorporate influent TP The goal is to incorporate influent TP into cell mass for BPRinto cell mass for BPRThe goal is to precipitate residualThe goal is to precipitate residualThe goal is to precipitate residual The goal is to precipitate residual soluble P with alum or ferric into a soluble P with alum or ferric into a settleablesettleable solidssolidssettleablesettleable solidssolids

How Much can we save How Much can we save from Optimization?from Optimization?

Electrical : 15 to 25% to begin withElectrical : 15 to 25% to begin withElectrical : 15 to 25% to begin withElectrical : 15 to 25% to begin withChemicals : Most of them, but it Chemicals : Most of them, but it depends on wastewater characteristicsdepends on wastewater characteristicsdepends on wastewater characteristics depends on wastewater characteristics of your plantof your plantSl d dittSl d dittSludge : dittoSludge : ditto

Process OverviewProcess OverviewProcess OverviewProcess Overview

Clarifier FilterPreliminary Treatment

Biological

Raw Influent

Disinfection

Biological Process

Solids Handling

Final EffluentEffluent

How do you do Remove How do you do Remove yyP biologically?P biologically?

Cultivate Phosphorus Accumulating Cultivate Phosphorus Accumulating Organisms(PAO)Organisms(PAO)g ( )g ( )–– Need carbon substrateNeed carbon substrate-- VFAVFA–– Time to grow themTime to grow themTime to grow themTime to grow them–– No oxygen environmentNo oxygen environment

P can be 4P can be 4 –– 6 % of cell biomass6 % of cell biomassP can be 4 P can be 4 –– 6 % of cell biomass 6 % of cell biomass compared to 1 to 1.5% by weightcompared to 1 to 1.5% by weight

Design ConsiderationsDesign Considerations-- wastewater wastewater ggcharacteristics characteristics

Waste Characteristics Waste Characteristics : : pastpast and futureand future–– CBODCBOD55CBODCBOD5 5

–– TSS TSS -- VSSVSS–– TN / TKNTN / TKN–– TN / TKNTN / TKN–– TP TP -- OrthoOrtho-- PP

AlkalinityAlkalinity Volatile acidsVolatile acids–– Alkalinity Alkalinity -- Volatile acidsVolatile acids–– pHpH

CODCOD dil bi d d bl CODdil bi d d bl COD–– COD COD -- readily biodegradable CODreadily biodegradable COD

To meet 1 mg/l TP by To meet 1 mg/l TP by g/ yg/ yBPR, we need VFA BPR, we need VFA parameters Minimum

COD: TP 40-45

BOD: TP 20

rb COD: TP 10- 16

VFA:TP 4 16VFA:TP 4-16

Volatile Fatty acidsVolatile Fatty acidsVolatile Fatty acidsVolatile Fatty acidsVFA P Update/VFA COD % in WastewaterVFA P Update/VFA COD % in Wastewater

Acetic Acid 0.37 60

Propionic 0.10 30

Butyric 0.12 10 for the rest

isobutyric 0.14 “

Valeric 0.15 “

Isovaleric 0.24 “

Sources of Volatile Fatty Sources of Volatile Fatty Acids : we need 15Acids : we need 15 2020Acids : we need 15Acids : we need 15--20 20 mg/lmg/lg/g/

Sewers Sewers –– the longer, the better the longer, the better InIn--Plant Recycles :Plant Recycles :InIn Plant Recycles : Plant Recycles : thickeners/anaerobic digesters/holding thickeners/anaerobic digesters/holding tankstankstankstanksFermentation of primary sludge or RAS Fermentation of primary sludge or RAS at the plant in new tanksat the plant in new tanks a 2a 2ndndat the plant in new tanks at the plant in new tanks –– a 2a 2ndnd

choicechoiceC i lC i l 33rdrd h ih iCommercial sourcesCommercial sources-- a 3a 3rdrd choicechoice

IF you do not have IF you do not have yyenough VFA, two optionsenough VFA, two options

Retrofit existing thickeners or other Retrofit existing thickeners or other tanks tanks Build a new Build a new fermenterfermenter

FermenterFermenter for Primary for Primary SludgeSludgeSludgeSludgeHRT : 6HRT : 6-- 12 hours12 hoursSRT : 4 SRT : 4 –– 8 days8 days

0.3 g VFA/g solids0.3 g VFA/g solidsg /gg /g0.06 0.06 –– 1.5 g VFA/total solids on COD1.5 g VFA/total solids on COD

TemperatureTemperatureTemperatureTemperature

Pontiac, MIPontiac, MIGenesee County MIGenesee County MIGenesee County, MIGenesee County, MI

Secondary ReleaseSecondary Release--causes and theircauses and theircauses and their causes and their preventionpreventionpp

Low pHLow pHChemical toxicityChemical toxicityExcess anaerobic respiration/digestionExcess anaerobic respiration/digestionExcess anaerobic respiration/digestionExcess anaerobic respiration/digestionLong SRTLong SRT

bbNitrate in anaerobic zoneNitrate in anaerobic zoneExcessive sludge blanketExcessive sludge blanket

D.O. Control : manual vs. D.O. Control : manual vs. automatic controlautomatic control

At Significant energy savingsAt Significant energy savings–– Aerobic ConditionsAerobic ConditionsAerobic ConditionsAerobic Conditions

2.0 mg/L2.0 mg/Las low as 1.0 mg/L at peak conditionsas low as 1.0 mg/L at peak conditions

–– Anoxic ConditionsAnoxic ConditionsD.O. “No”D.O. “No”Nitrates “Yes”Nitrates “Yes”

–– Anaerobic ConditionsAnaerobic ConditionsD.O. “No”D.O. “No”Nitrates “No”Nitrates “No”

BPR DesignBPR DesignBPR DesignBPR Design

Design to include an anaerobic zoneDesign to include an anaerobic zoneDesign HRT for anaerobic zone usually Design HRT for anaerobic zone usually g yg yranges from 0.5 hours to 1.5 hoursranges from 0.5 hours to 1.5 hoursDO and DO and NOxNOx must be exhausted to workmust be exhausted to workBaffling is a common design techniqueBaffling is a common design techniqueAnaerobic zone is almost always the first Anaerobic zone is almost always the first yyprocess basin to maximize VFAs in the raw process basin to maximize VFAs in the raw influentinfluent

Retrofit Examples in MIRetrofit Examples in MIRetrofit Examples in MIRetrofit Examples in MI

Pontiac, MIPontiac, MI-- First Cold Weather First Cold Weather Demonstration in 1984Demonstration in 1984--66Genesee County, MI: Best BPR plant Genesee County, MI: Best BPR plant w/o chemical or filterw/o chemical or filterw/o chemical or filterw/o chemical or filterKalamazoo, MI : under construction, Kalamazoo, MI : under construction, 2010201020102010

A/O Process: Anaerobic & A/O Process: Anaerobic & //aerobic zonesaerobic zones

1 hr HRT 5 hr HRT

Genesee Co., MI, 20 MGD, AS/Land , , ,Application of Biosolids

BPR ClarifierPrimarySettling Clarifierg

Lime StabilizationBiosolids Land

ApplicationStorage

Genesee CountyGenesee CountyGenesee County Genesee County 100.0000

10.0000

L

Raw Influentmean = 4.45 mg/Lst. dev = 0.66 mg/LCOV = 15%

1.0000

hosp

horu

s, m

g/L

Primary Effluentmean = 3.71 mg/Lst. dev = 0.63 mg/LCOV = 17%

0.1000

Tota

l Ph

Final Effluentmean = 0.26 mg/Lst. dev = 0.068 mg/L

0.0100

5030201051 20.05 70 80 90 95 98 99.5 99.95

gCOV = 26%

Percent Less Than or Equal To

Raw Influent Primary Effluent Final Effluent

10

6

79

L 6

2

3

8

4

5

1

Phos

phor

us, m

g/L

1

810

0.1Tota

l P

0.01

Percent Less Than or Equal To0.1 504030201051 20.50.05 60 70 80 90 95 98 99 99.5 99.9599.9

1 - Step Feed w/ Fermenter-Piscataway, MD 6- Five-stage Bardenpho-Northeast, Clearwater, FL2 - EBPR w/ VFA Addn + Filters-Kalispell, MT 7 - Denitrification Filters + Chem Addn-Johnston Co., NC3 - Five-stage Bardenpho-Marshall St., Clearwater, FL 8 - A/O--Genesee Co., MI4 - A2O with VFA, chemical, and filter-Durham, OR 9 - Phased Isolation Ditch-North Cary, NC5 - Westbank--Kelowna, BC 10 - Triple sludges---Western Branch, MD.

Medium-Level Phosphorous Removal Plants

1

10

56

0.1

1

spho

rus,

mg/

L

1

234

7

0.01

Tota

l Pho

s

0.0010.1 504030201051 20.50.05 60 70 80 90 95 98 99 99.5 99.9599.9

Percent Less Than or Equal To1 - Chem Addn + Tert Clarifiers + Land Application-Brighton, MI2 - Biofor, DensaDeg, and MBR-Breckenridge, CO (only Ann. Ave. and Max Month available)3 - MBR-Lone Treek Creek, CO4 - 5 Stage Bardenpho w chemical and filter, Pinery, CO5 - Tert Clarifier + Chem Addn + Filter-McMinnville, OR6 - MBR + Chem Addn-Hyrum, UT7-Denite filter Lee County, FL

Low Level Phosphorus Removal Plants

Brighton, MI, 1.3 MGD, OD/Filter/Land g , , ,Application

FeCl3FeCl3Slow SandFilt Land

FeCl3

Oxidation

Filter Land Application

DitchClarifier

ClariconeFi lFinal

Effluent

Typical Energy Usage in Typical Energy Usage in yp gy gyp gy gU.S. WWTPsU.S. WWTPs

Average Plant : 1500 KWh/Million Gallons Average Plant : 1500 KWh/Million Gallons (MG) treated for secondary treatment(MG) treated for secondary treatmentAdvanced Treatment Plant: 2000 Advanced Treatment Plant: 2000 –– 3000 3000 KWh/MGKWh/MG/ G/ G

Where do we use Where do we use electricity?electricity?

Is Energy SelfIs Energy Self--Sufficiency Sufficiency gygy yyFeasible in the U.S.?Feasible in the U.S.?

Proven in concept and practice inProven in concept and practice inProven in concept and practice in Proven in concept and practice in Strass, Austria, a 10 MGD plantStrass, Austria, a 10 MGD plant

Strass, Austria WWTPStrass, Austria WWTP

3000000

3500000Power Generated > Power Used

2000000

2500000

year

1000000

1500000

kW-h

r/y

500000

1000000

0

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

Power Used Power Generated

Wett, Buchauer, and Fimml, Asian Water Conference, 2007

Technical Features at Technical Features at StrassStrass

TwoTwo--stage biological process to stage biological process to transfer maximum amount of organic transfer maximum amount of organic ggmatter from liquid phase to solid matter from liquid phase to solid phasephaseppOnOn--line control of aerationline control of aerationNew CHP equipment: 38% efficiencyNew CHP equipment: 38% efficiencyNew CHP equipment: 38% efficiency New CHP equipment: 38% efficiency in power generationin power generationSidSid t t t tt t t tSideSide--stream treatmentstream treatment

Comparison of U.S. to Comparison of U.S. to ppStrass: UsageStrass: Usage

PerPer--person water usage is twice in the U.S.person water usage is twice in the U.S.PerPer--person energy usage is higher than that of person energy usage is higher than that of StSt d td tStrassStrass due to:due to:–– Traditional U.S. practices in design and operationTraditional U.S. practices in design and operation–– Increased mixing power needsIncreased mixing power needsg pg p–– Increased pumping power needsIncreased pumping power needs

StrassStrass is more aggressive at optimization than is more aggressive at optimization than t i l US tit i l US titypical US practicetypical US practice

Roadmap to SelfRoadmap to Self--ppSufficiencySufficiency

100BNR-optimization

Side-Stream Treatment

On-Line Sensors

Automatic Controls and HVAC

Turndown Capabilities

Swing Zones50 Min

Ratio3:1

Anaerobic Digestion/Co-Digestion

Turndown Capabilities

Commitment, Regulations, Incentives and Trainingg g

0Feasibility Study and Technology Innovation and Demonstration

BioBio gas Factsgas FactsBioBio--gas Facts gas Facts

Average PE generates wastewater at Average PE generates wastewater at 100 100 gpdgpdgpgpApprox. 1 cubic foot of digester Approx. 1 cubic foot of digester gas/d/PE via anaerobic digestiongas/d/PE via anaerobic digestiongas/d/PE via anaerobic digestiongas/d/PE via anaerobic digestion600 BTU/c.f.600 BTU/c.f.100kW f l t i it f 4 5 MGD100kW f l t i it f 4 5 MGD100kW of electricity from 4.5 MGD 100kW of electricity from 4.5 MGD plantplant

Optimization at your Optimization at your p yp yplant?plant?

Feasibility studyFeasibility studyMonitoring of wastewaterMonitoring of wastewater –– influentinfluentMonitoring of wastewater Monitoring of wastewater influent influent and inand in--plant recyclesplant recyclesEnergy analysis and contracts w/utilityEnergy analysis and contracts w/utilityEnergy analysis and contracts w/utilityEnergy analysis and contracts w/utilityDevelopment of alternatives : Energy, Development of alternatives : Energy, Ch i l Sl dCh i l Sl dChemical, SludgeChemical, SludgeFunding Funding –– Local or Pay as you go from Local or Pay as you go from savingssavingsImplementationImplementation

Pilot Demonstration?Pilot Demonstration?Pilot Demonstration?Pilot Demonstration?

Take one train and testTake one train and testConvert a thickener on siteConvert a thickener on siteConvert a thickener on siteConvert a thickener on siteOther tanks Other tanks

Summary (1)Summary (1)Summary (1)Summary (1)

Bio Phosphorus removal is proven, Bio Phosphorus removal is proven, reliable, and efficient with reliable, and efficient with fermenterfermenter..,,–– VFA is VFA is neeedneeed from the wastewater or from the wastewater or

fermenterfermenter–– PAO has specific needs to growPAO has specific needs to grow–– FermenterFermenter design has improveddesign has improvede e tee e te des g as p o eddes g as p o ed

Energy Optimization is a way to keep Energy Optimization is a way to keep the funds at the citythe funds at the citythe funds at the citythe funds at the city

Summary(2)Summary(2)Summary(2)Summary(2)

BPR BPR -- meet the permitmeet the permitSaves chemical energy and sludgeSaves chemical energy and sludgeSaves chemical, energy and sludge Saves chemical, energy and sludge management costsmanagement costsEnvironmentally sustainable operationEnvironmentally sustainable operationEnvironmentally sustainable operationEnvironmentally sustainable operationQuality of Life is enhancedQuality of Life is enhancedSaves jobsSaves jobs