SLIDE 1
What is Bio P Removal?
- It is NOT a mysterious brown box
Biological Phosphorous Removal An Operators Guide Glenn Burkhardt, - - PowerPoint PPT Presentation
Biological Phosphorous Removal An Operators Guide Glenn Burkhardt, - - PowerPoint PPT Presentation
Biological Phosphorous Removal An Operators Guide Glenn Burkhardt, PE Engineered Logic LLC What is Bio P Removal? It is NOT a mysterious brown box Bio P Model Two Step Process (Anaerobic then Aerobic) Acetate + Poly- P PHA + ATP
SLIDE 2
SLIDE 3
Bio P Model
- Two Step Process (Anaerobic then Aerobic)
Acetate + Poly-P → PHA + ATP → H20 + CO2 ← Anaerobic → ← Aerobic →
SLIDE 4
Bio P Process Discussion
- Anaerobic Step
- Carbon Conversion to Volatile Fatty Acids
- Volatile Fatty Acid Conversion to Acetate
- Acetate & Poly-P Conversion to PHA & ATP
PHA Polyhydroxyalkanoic Acid ATP Adenosine Triphosphate
- Aerobic Step
- PHA & ATP Conversion to Glycogen, H2O & CO2
SLIDE 5
Phosphorous Uptake Diagram
Anaerobic→← Aerobic
10 20 30 40 50 60 25 50 75 100 150 200 300
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Treatment Process Diagram
- A/O Process
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Anoxic Zone
SLIDE 8
Aerobic Zone
SLIDE 9
Important Design Parameters
- BOD to P ratio > 20
- COD to P ratio > 45
- VFA to P ratio > 7
- Anaerobic HRT 1 to 2 hours
- Aerobic SRT 15 to 20 days
- Nitrate Loading < O2 Demand of Waste
SLIDE 10
Important Operating Parameters
- Anaerobic Zone pH 8.0 to 8.5
- Anaerobic Zone ORP -100 to -200 mV
- Aerobic Zone pH 7.0 to 7.5
- Aerobic Zone ORP +100 to +300 mV
- Return Sludge Rate Manage ML Conc.
Maintain ORP Limits
SLIDE 11
pH and ORP Monitoring
SLIDE 12
Bio P Troubleshooting
- Phosphorous Increasing (normal NH3 & SS)
- P uptake could be due to low VFA production
- ATP production could be affected by anaerobic pH
- Nitrates could be affecting anaerobic conditions
- Parameters to Check
- VFA to P ratio (greater than 7)
- Anaerobic reactor pH (8.0 to 8.5)
- Anaerobic reactor ORP (-100 to -200 mV)
SLIDE 13
Bio P Troubleshooting
- Rapid P Increase (normal NH3 & SS)
- Side Stream with High P Being Introduced
- P Release from Clarifier Sludge Blanket
- P Release from High Solids Retention time
- Parameters to Check
- P Concentration to Anaerobic Reactor
- ORP of Sludge Blanket ( 0 to 100 mV is the goal )
- Soluble P of Mixed Liquor ( < 0.5 mg/l is the goal )
SLIDE 14
Bio P Troubleshooting
- High Effluent P ( high effluent SS)
- Could be due to High Effluent Solids
- Could be due to P Release
- Could be due to Aerobic Reactor pH
- Parameters to Check
- Check P of Filtered Effluent Sample
- Check P Profile of Anaerobic and Aerobic Reactors
- Check pH of Anaerobic and Aerobic Reactors
SLIDE 15
Bio P Performance
- Improved Solids Settling Characteristics
- Less Risk of Aerobic Reactor Foaming
- More Stable Under Shock Loading Conditions
- No Chemicals Required
- Less Sludge Production
- Effluent P Typically 0.2 to 0.5 mg/l
- Effluent NH3 Typically < 0.5 mg/l
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