Bioscience, Bioscience, Inc. Inc. Allentown, PA Allentown, PA www.bioscienceinc.co www.bioscienceinc.co m m
Feb 01, 2016
Bioscience, Inc.Bioscience, Inc.
Allentown, PAAllentown, PA
www.bioscienceinc.comwww.bioscienceinc.com
The Biological Process of The Biological Process of Wastewater TreatmentWastewater Treatment
Jay HillJay Hill
Product ManagerProduct Manager
• Coarse Physical TreatmentCoarse Physical Treatment
• Settling of Suspended Settling of Suspended Solids/FloatablesSolids/Floatables
• Biological Treatment of Dissolved/ Biological Treatment of Dissolved/ Fine SolidsFine Solids
• Recovery of BiomassRecovery of Biomass
• Removal of InorganicsRemoval of Inorganics
• DisinfectionDisinfection
• Excess Biomass RemovalExcess Biomass Removal
Typical Wastewater Typical Wastewater Treatment StepsTreatment Steps
Primary TreatmentPrimary Treatment
• Bar ScreenBar Screen
• ClarifierClarifier– Primary sludgePrimary sludge
• Sand/gritSand/grit
• Coarse organic matterCoarse organic matter
– FloatablesFloatables• FOGFOG
• DAF or API SeparatorDAF or API Separator– FOG, petroleum HC, light solidsFOG, petroleum HC, light solids
Activated Sludge Activated Sludge SystemsSystems
Untreated Discharge
Aeration Tank Clarifier
Recycled Sludge
Biomass (Secondary
Sludge)
Clean Water
O2 CO2
Secondary ClarificationSecondary Clarification
• ClarifierClarifier– Secondary sludgeSecondary sludge
• Fine organic matterFine organic matter
– FloatablesFloatables• FOGFOG
Solids ProcessingSolids Processing
• Sludge ThickeningSludge Thickening
• Aerobic or Anaerobic DigestionAerobic or Anaerobic Digestion
• CentrifugeCentrifuge
• Belt PressBelt Press
• Incineration, Land Application, Fertilizer, Incineration, Land Application, Fertilizer, LandfillLandfill
Aerobic MicrobialAerobic Microbial
RespirationRespiration
C,H + O2 CO2 + H2O
+ protein
*
* bacteria, N, P, pH, temperature
Composition of Composition of WastewaterWastewater
InorganicsInorganics AmmoniaAmmonia NitrateNitrate PhosphatePhosphate CarbonateCarbonate MineralsMinerals
CalciumCalcium MagnesiumMagnesium IronIron Etc.Etc.
OrganicsOrganics Biodegradable (BOD)Biodegradable (BOD)
CarbohydratesCarbohydrates Proteins (TKN)Proteins (TKN) FOGFOG
Non-Biodegradable Non-Biodegradable (COD-BOD)(COD-BOD)
Large particlesLarge particles Complex polymers Complex polymers
(plastics, lignin)(plastics, lignin) Surfactants (some)Surfactants (some) Pesticides (some)Pesticides (some) Pharmaceuticals Pharmaceuticals
(some)(some)
TemperatureTemperature pHpH Water activityWater activity Energy sourceEnergy source NutrientsNutrients
CarbonCarbon NitrogenNitrogen PhosphorusPhosphorus MineralsMinerals Vitamins/growth factorsVitamins/growth factors
Requirements for Growth Requirements for Growth of Microbesof Microbes
ThermophilesThermophiles 40°C to >100°C40°C to >100°C
MesophilesMesophiles 10°C to ~45°C10°C to ~45°C
PsychrophilesPsychrophiles <5°C to ~35°C<5°C to ~35°C
TemperatureTemperature
AcidophilesAcidophiles pH 0-6pH 0-6
AlkaliphilesAlkaliphiles pH 8-13pH 8-13
Most bacteria prefer pH 6-8Most bacteria prefer pH 6-8 Most fungi prefer pH 4-7Most fungi prefer pH 4-7
pHpH
Salt content of waterSalt content of water Fresh water <1% NaCl (most bacteria)Fresh water <1% NaCl (most bacteria) Brackish water ~1-3% NaCl (limits some Brackish water ~1-3% NaCl (limits some
species)species) Seawater ~3.5% NaCl (salt tolerant only)Seawater ~3.5% NaCl (salt tolerant only) Saline water up to 30+% (saturated NaCl)- Saline water up to 30+% (saturated NaCl)-
(only few species)(only few species) Soils (moisture content and salts)Soils (moisture content and salts)
50-100% FMC (most bacteria)50-100% FMC (most bacteria) Fungi tolerate lower moisture contentFungi tolerate lower moisture content
Water ActivityWater Activity
Oxygen (aerobes) COxygen (aerobes) C66HH1212OO66+ 6 O+ 6 O226 CO6 CO22+6 +6 HH22OO AutotrophsAutotrophs
NHNH44+++ 2 O+ 2 O22 NO NO33
--+ H+ H22O + 2 HO + 2 H+ + (Nitrifiers)(Nitrifiers) HH22S + 2 OS + 2 O22 SOSO44 - - - - + 2 H+ 2 H+ + (sulfur oxidizers)(sulfur oxidizers) HH22S + 0.5 OS + 0.5 O22 SS0 0 + H+ H22O (sulfur oxidizers)O (sulfur oxidizers)
Nitrate (facultative) CNitrate (facultative) C66HH1212OO6 6 + 6 H+ 6 H22OO 6 CO6 CO22+ + 12 H12 H22 / 5 H / 5 H22 +2 NO +2 NO33 - - + 2 H+ 2 H+ + N N2 2 + 6 H+ 6 H22O O (denitrifiers)(denitrifiers)
Sulfate (anaerobes) CSulfate (anaerobes) C22HH44OO22COCO2 2 / SO/ SO44 ---- H H22S S (sulfate reducers)(sulfate reducers)
Carbon dioxide (anaerobes) COCarbon dioxide (anaerobes) CO22+ 4 H+ 4 H22 CHCH4 4
+2 H+2 H22O (methanogens)O (methanogens)
Fermentation CFermentation C66HH1212OO662 CO2 CO22+2 C+2 C22HH55OHOH
Energy SourcesEnergy Sources
Nutrients Required for Nutrients Required for GrowthGrowth
CarbonCarbon Usually from food source or COUsually from food source or CO22
NitrogenNitrogen Usually from ammonia, nitrate Usually from ammonia, nitrate
or simple organics (amino or simple organics (amino acids)acids)
PhosphorusPhosphorus Inorganic phosphateInorganic phosphate
SulfurSulfur Inorganic sulfate or simple Inorganic sulfate or simple
organicsorganics Minerals (Ca, Mg, K, Na, Fe)Minerals (Ca, Mg, K, Na, Fe) Trace elements (Ni, Co, Cu, Mo, Trace elements (Ni, Co, Cu, Mo,
Zn)Zn) Growth factors/vitaminsGrowth factors/vitamins
Operation LimitsOperation Limits
pH 6-9pH 6-9<4: Most bacteria dead or <4: Most bacteria dead or
inactiveinactive
<6: Bacteria activity drops, <6: Bacteria activity drops, fungi may create settling fungi may create settling problemproblem
<6.5: Nitrification very poor<6.5: Nitrification very poor
7.5: optimum for 7.5: optimum for hydrocarbons, fog, hydrocarbons, fog, nitrification, sulfidenitrification, sulfide
>9: Bacteria activity drops>9: Bacteria activity drops
NutrientsNutrientsBOD:N:P = 100:5:1BOD:N:P = 100:5:1
Effluent ammonium-N <2 mg/L Effluent ammonium-N <2 mg/L may limit BOD removal or slow may limit BOD removal or slow response to slug loadingresponse to slug loading
Effluent ammonium-N <0.5 mg/L Effluent ammonium-N <0.5 mg/L probably deficient unless probably deficient unless nitrifying (nitrate provides N)nitrifying (nitrate provides N)
Effluent ortho-phosphate <1 mg/L Effluent ortho-phosphate <1 mg/L may limit BOD removal or slow may limit BOD removal or slow response to slug loadingresponse to slug loading
Effluent ortho-phosphate <0.2 Effluent ortho-phosphate <0.2 mg/L probably deficient mg/L probably deficient
Operation LimitsOperation Limits
TemperatureTemperature<5°C Few bacteria are active<5°C Few bacteria are active
<15°C Nitrification and most <15°C Nitrification and most bacteria growth very slowbacteria growth very slow
20-35°C Optimum for most 20-35°C Optimum for most bacteriabacteria
39-45°C Bacteria activity 39-45°C Bacteria activity drops, death rate increasesdrops, death rate increases
>45°C Only adapted or >45°C Only adapted or thermophilic processes thermophilic processes occuroccur
BiomassBiomassMLSS normally 1500-6000 MLSS normally 1500-6000
mg/Lmg/L
<1500 poor settling, dispersed <1500 poor settling, dispersed
>6000 oxygen limited?; may >6000 oxygen limited?; may overflow clarifier weiroverflow clarifier weir
MLSS/MLVSS 80-90%MLSS/MLVSS 80-90%
<80% low viable percentage, <80% low viable percentage, possible accumulation of possible accumulation of inertinert
<70% may occur in aerobically <70% may occur in aerobically digested sludgedigested sludge
>90% light (poor settling) floc>90% light (poor settling) floc
Operation LimitsOperation Limits
Sludge Age/MCRTSludge Age/MCRT<3 days Poor settling/COD <3 days Poor settling/COD
removal/high sludge removal/high sludge productionproduction
<8 days May have poor <8 days May have poor nitrificationnitrification
>20 days May have filament >20 days May have filament problems or pin floc; good problems or pin floc; good for exotic chemical for exotic chemical degradation and sludge degradation and sludge digestiondigestion
SOURSOURComplete mix system 3-15 mg Complete mix system 3-15 mg
O2/g MLSS per hourO2/g MLSS per hour
<3 Inhibition or severe <3 Inhibition or severe underloadunderload
>15 Slug load/ possible >15 Slug load/ possible overloadingoverloading
Staged aeration –1Staged aeration –1stst Stage Stage
30-100 mg O2/g MLSS per hour30-100 mg O2/g MLSS per hour
<20 Inhibition<20 Inhibition
<30 Insoluble waste `<30 Insoluble waste `
>100 Overloading>100 Overloading
Operation LimitsOperation Limits
Dissolved OxygenDissolved Oxygen2-7 mg/L normal range2-7 mg/L normal range
<0.5 Anaerobic <0.5 Anaerobic
<1 General BOD removal slows<1 General BOD removal slows
<2 Nitrification slows<2 Nitrification slows
>7 Slow growth (inhibition) or >7 Slow growth (inhibition) or underloadedunderloaded
>9 Bacteria dead or inactive>9 Bacteria dead or inactive
Sludge Blanket Sludge Blanket Normal range 3-7 ft below Normal range 3-7 ft below
surfacesurface
<3 feet(1 meter) poor settling <3 feet(1 meter) poor settling or compaction; biomass or compaction; biomass may washout with flow may washout with flow increaseincrease
>7 feet (2 meters) Rapid >7 feet (2 meters) Rapid settling may leave settling may leave dispersed solids in effluentdispersed solids in effluent
Typical UpsetsTypical UpsetsHeavy Organic Load
Increased Growth/Respiration
Reduced Dissolved Oxygen
More Sludge to Clarifier
Reduced Growth/Respiration
Inadequate Removal
Deflocculation of the BiomassPoor Settling
Worse Effluent Elevated BOD/COD
High Effluent Suspended Solids
Common Wastewater Common Wastewater ProblemsProblems
Poor SettlingPoor Settling Effluent Violation (TSS or BOD)Effluent Violation (TSS or BOD) Filamentous FormsFilamentous Forms Poor NitrificationPoor Nitrification ToxicityToxicity OdorsOdors
Aerobic MicrobialAerobic Microbial
RespirationRespiration
C,H + O2 CO2 + H2O
+ protein
*
* bacteria, N, P, pH, temperature
Chemical Characterization of Chemical Characterization of VISC 25VISC 25
Parameter Result Comments
pH of 10% solution 10.5
Alkalinity 37 meq/100 g Titrated to pH 7 w/HCl
Ammonium-Nitrogen 400 mg/L
Nitrite-Nitrogen 5 mg/L Color fades rapidly
Nitrate-Nitrogen <5mg/L Turns yellow after cadmium addition
Phosphate-Phosphorus 30 mg/L
Chemical Oxygen Demand 71,000 mg/L
Wastewater Treatment Plant Wastewater Treatment Plant Performance Testing Performance Testing
Process control tests or performance evaluation tests to determine overall Process control tests or performance evaluation tests to determine overall treatment process efficiency, identify or investigate problems, or treatment process efficiency, identify or investigate problems, or evaluate specific ability to treat target compounds. Process control tests evaluate specific ability to treat target compounds. Process control tests generally must be quick turnaround tests usually performed on-site to generally must be quick turnaround tests usually performed on-site to allow process adjustment in response to problems. However, some allow process adjustment in response to problems. However, some longer time-frame tests may be set up to predict or determine the effect longer time-frame tests may be set up to predict or determine the effect
of process changes or identify trends in process efficiency.of process changes or identify trends in process efficiency.
Some of the investigations performed by Bioscience have been designed to:Some of the investigations performed by Bioscience have been designed to:
1.1. evaluate foam or settling problemsevaluate foam or settling problems
2.2. measure nitrification rates or nitrification potentialmeasure nitrification rates or nitrification potential
3.3. measure FOG degradation rates or potentialmeasure FOG degradation rates or potential
4.4. measure permissible loading rates for potentially toxic waste streams or measure permissible loading rates for potentially toxic waste streams or septageseptage
5.5. measure effectiveness of bioaugmentationmeasure effectiveness of bioaugmentation
6.6. measure biomass kinetic constants for process design.measure biomass kinetic constants for process design.
Wastewater Treatment Plant Wastewater Treatment Plant Performance Testing Performance Testing
Available methods include:
Standard Methods 5210D Biochemical Oxygen Demand
Respirometric Method (Respirometric Oxygen Uptake)
Standard Methods 2710B Oxygen-Consumption Rate (Specific Oxygen
Uptake Rate; Dissolved Oxygen Probe Method)
OECD 209 Activated Sludge, Respiration Inhibition Test
ASTM D5120 Standard test Method for Inhibition of Respiration in the
Activated Sludge Process
Short-Term BOD Test (EZ-BOD instrument test for influent or effluent
BOD-5 estimation)
Suspended Solids (Photometric Method)
CONTRAL Biodegradation Kinetics
Microscopic Evaluation of Biomass (Higher Forms and Filaments)
Wastewater Treatment Problems Wastewater Treatment Problems (AS)(AS)
ProblemProblem CauseCause CureCureFOG in collectionFOG in collection VariousVarious DNT-RF/GELDNT-RF/GEL
Odor/HOdor/H22SS Anaerobic conditionAnaerobic condition DNT-RF/ANLDNT-RF/ANL
FOG in aeration basinFOG in aeration basin Slow digestionSlow digestion DNT-RF/SXM/NPN/TMDNT-RF/SXM/NPN/TM
High temperature/low High temperature/low activityactivity
Hot process waterHot process water HTHT
No or partial No or partial nitrificationnitrification
Toxicity/low temp/low Toxicity/low temp/low SRT/nutrientsSRT/nutrients
XNC/XNL/TMXNC/XNL/TM
Low COD or specific Low COD or specific compound removalcompound removal
Low temp Low temp /various/industry /various/industry specificspecific
HX, XR, XP, etc.HX, XR, XP, etc.
Excessive filamentsExcessive filaments variousvarious XF, SXM, nutrientsXF, SXM, nutrients
Excessive sludgeExcessive sludge FOG/cellulose/etc FOG/cellulose/etc accumulation in sludgeaccumulation in sludge
SRSR
Poor sludge digestionPoor sludge digestion Nutrient Nutrient imbalance/FOGimbalance/FOG
AD, SXM, TMAD, SXM, TM
Wastewater Treatment Problems (Lagoon)Wastewater Treatment Problems (Lagoon)
ProblemProblem CauseCause CureCureOdor/HOdor/H22SS
Odor/NHOdor/NH33
Anaerobic conditionAnaerobic condition
High NHHigh NH33 /High pH /High pHANL/TN and/or aerationANL/TN and/or aeration
ECLECL
FOG in aeration basinFOG in aeration basin Slow digestionSlow digestion DNT-RF/SXM/NPN/TMDNT-RF/SXM/NPN/TM
High temperature/low High temperature/low activityactivity
Hot process waterHot process water HTHT
No or partial No or partial nitrificationnitrification
Toxicity/low temp/low Toxicity/low temp/low SRT/nutrientsSRT/nutrients
XNC/XNL/TMXNC/XNL/TM
Low COD or specific Low COD or specific compound removalcompound removal
Low temp Low temp /various/industry /various/industry specificspecific
LF, HX, XR, XP, etc.LF, HX, XR, XP, etc.
Excessive sludgeExcessive sludge FOG/cellulose/etc FOG/cellulose/etc accumulation in sludgeaccumulation in sludge
SRSR
Animal waste Animal waste consistencyconsistency
High solidsHigh solids DLDL
AlgaeAlgae High nutrients (N,P)High nutrients (N,P) AL/ALNAL/ALN
Poor denitrificationPoor denitrification Low facultative Low facultative populationpopulation
DENDEN
BioaugmentationBioaugmentation
How Does Bioaugmentation WorkHow Does Bioaugmentation Work??
• Numbers – By adding cultures regularly the minor cultures (but important cultures) gain a survival advantage (against the dominant cultures) .• Natural Genetic Interchange – Recent work indicates the possibility of transfer to the biomass of desirable and needed characteristics (but not permanently), particularly capabilities controlled by the plasmids in the cells and demanded by the conditions in the system.
Activated SludgeActivated Sludge- - Culture Selector Culture Selector
The biomass is comprised of thousands of cultures of bacteria, fungi, protozoans, etc.
The system “selects” cultures with both major/dominant populations and minor counts. Both populations are important in obtaining good effluent quality.
The combination of cultures in the biomass continuously changes and adapts to changes in ambient conditions.
Major Versus Minor Major Versus Minor CulturesCultures
• Major Cultures
Grow rapidly
settle well
control the general nature of the biomass• Minor Cultures
Produce important results
Are more difficult to maintain in the biomass
The Transfer The Transfer ofof PlasmidPlasmidss
a b
cd
Scientific American, January 1998, p. 68
Bioaugmentation Bioaugmentation BenefitsBenefits
Benefits for Wastewater Treatment:Benefits for Wastewater Treatment: Reduce Effluent Peaks (NPDES Reduce Effluent Peaks (NPDES
outages)outages) Reduce Effects of Toxic CompoundsReduce Effects of Toxic Compounds Improve Settling Thru Filament ControlImprove Settling Thru Filament Control Enhance Process StabilityEnhance Process Stability Reduce Sludge ProductionReduce Sludge Production Minimize Downtime/Reduce LaborMinimize Downtime/Reduce Labor
Filamentous Filamentous PopulationsPopulations
Individual microbes do the work
Microbes flocculate and form particles that settle
But the filamentous forms inhibit settling
NitrificaNitrificationtion
2NH4+ + 3O2 2NO2
- + 4H+ + 2H2O2NO2
- + O2 2NO3-
NH3 Treatment NH3 Treatment SystemSystem
Removal of insolubles
Removal of BOD
Removal of NOD
Clarifier
Clarifier
Recycle of Sludge
Recycle of Sludge
Discharge of Sludge
Discharge of Sludge