Biological and Chemical Systems for Nutrient Removal
Table of Contents
Chapter
1. Nutrients and Their Effects on the Environment
Overview
Point Source Control
Nonpoint Source Control
Nutrient Control Strategies
Effect on the Environment
General
Flowing Water Bodies
Ammonia-Nitrogen
Nitrogen and Phosphorus
Stationary Water Bodies
Land Environment
Irrigation
Nutrient Removal
Groundwater Recharge
Deep Well Injection
Surface Spreading and Percolation
Nutrient Forms, Sources, and Cycles
Nitrogen Compounds
Nitrogen Sources
Typical Nitrogen Concentrations
Phosphorus
Typical Phosphorus Concentrations
Effluent Limits
Concentration and Mass Loadings Criteria
Ammonia Toxicity
Analytical Techniques
Nitrogen Analyses
Phosphorus Analyses
References
Overview of Nutrient Removal Processes
Nitrogen Removal
Biological Nitrogen Removal
Suspended-Growth Processes
Fixed Film Processes
Biological Nitrogen Removal Schemes
Physical/Chemical Nitrogen Removal Processes
Breakpoint Chlorination
Air Stripping
Phosphorus Removal Processes
Biological Phosphorus Removal
Chemical Phosphorus Removal
References
2. Chemical Phosphorus Removal
Principles of Chemical Phosphorus Removal
Ferrous Iron
Ferric Iron and Aluminum
Calcium
Design Examples
Chemical Phosphorus Removal Process Design
Phosphorus Removal by Alum Addition to Raw Wastewater and Aeration Basin
Alum Dose Determination
Chemical Requirements and Storage
Sludge Generation from Alum Addition
Phosphorus Removal by Ferric Chloride Addition to Raw Wastewater before Primary Treatment
Ferric Iron Dose Determination
Chemical Requirements and Storage
Sludge Generation from Ferric Chloride Addition
References
Principles of Biological Nitrogen Removal
Nitrification
Stoichiometry
Kinetics
Value of Biokinetics Coefficients
Toxicity
Attached-Growth Systems
Denitrification
Biochemistry and Microbiology
Stoichiometry
Substrate Requirements
Alkalinity Production
Kinetics
Toxicity
References
3. Principles of Biological Phosphorus Removal
Enhanced Biological Phosphorus Removal
Microbiology
Biochemistry
Temperature and pH
Settleability of Enhanced Biological Phosphorus Removal
Activated Sludges
Oxygen Consumption
References
4. Nitrification Design
Overview and Process Options
Nitrification
Suspended-Growth Systems
Choice of Design Solids Retention Time
Single-Stage Nitrification
Two-Stage Nitrification
Mid-Step Nitrification
Selection of Configuration
Attached-Growth Systems
Trickling Filters
Single-Stage Trickling Filter
Two-Stage Trickling Filter
Rotating Biological Contactors
Single-Stage Rotating Biological Contractor
Two-Stage Rotating Biological Contactor
Biological Fluidized-Bed Reactors
Biological Aerated Filters
Design Examples
Single-Stage Activated-Sludge Process
Two-Stage Activated Sludge Process
References
5. Nitrogen Removal and Design of Combined Nitrification and Denitrification Processes
Separate-Stage Denitrification
Characteristics
Suspended Growth
Design Criteria
Design Equations
Design Example
Case History - River Oaks Advanced Wastewater Treatment Plant, Hillsborough County, Florida
Single-Sludge Nitrification-Denitrification
General Characteristics
Predenitrification System
Design Criteria
Design Equations
Aerobic Zone Calculations
Anoxic Zone Calculations
Oxygen Requirements
Alkalinity Requirements
Predenitrification Design Example
Metro Denver Wastewater Treatment Plant Case
History
Postdenitrification Systems
Design Criteria
Design Equations
Aerobic Zone Calculations
Anoxic Zone Calculations
Oxygen Requirements
Alkalinity Requirements
Postdenitrification Design Example
Main Street Wastewater Treatment Plant Case History
Combined Pre- and Postdenitrification Systems
Design Criteria
Design Equations
First-Stage Aerobic Zone Calculations
First-Stage Anoxic Zone Calculations
Calculations for Second Aerobic Zone
Check the Overall Design
Combined Pre- and Postdenitrification Design Example
Calculations for Second Aerobic Zone
Check the Overall Design
Case History
References
6. Design of Biological Phosphorus Removal Processes
Design Principles
Requirements for Enhanced Biological Phosphorus Removal
Poly-P Microbial Population Dynamics
Readily Available Substrate in the Anaerobic Zone
Phosphorus in Excess of Growth Needs
Magnesium and Potassium
Required PH Range
Factors Affecting Performance
Influent Available Substrate: Available Phosphorus Ratio
Phosphorus Limitation Versus Biochemical Oxygen Demand Limitation
Percent Phosphorus
Effect of Solids Retention Time
Anaerobic Hydraulic Retention Time
Temperature Effects
Effects of Primary Settling and Sludge Processing
Fundamentals of Prefermentation
Biological Prefermentation
Design of Systems for Optimizing Volatile Fatty Acid Production
Return of Organic Carbon
Monitoring of the Process
Practical Points about Prefermenters
Factors Affecting Substrate Storage
Electron Acceptor Recycle/Entrainment
Temperature Effects
Determination of Design Requirements
Sizing the Anaerobic Zone
Aeration Requirements
Mixing Requirements
Baffle Design
Secondary Clarifier Design and Operation
Supplemental Chemical Addition
Design Steps for Enhanced Biological Phosphorus Removal
Design Example
Alternate Design
Enhanced Biological Phosphorus Removal Configurations
Sidestream Continuous-Flow System
Mainstream Continuous-Flow System
Four-Stage Design
Five-Stage Design
Design Example
Cyclic Process Designs
Oxidation Ditch Configurations
Bio-DenitroTM/BioDeniphoTM Processes
Schreiber Processes
Sequencing Batch Reactor Process
Effluent Limitations
References
7. Structured Process Models for Biological Nutrient Control
Development of Models for Biological Nutrient Removal
Aspects of Nitrification, Denitrification, Enhanced Biological Phosphorus Removal
Model Development
Anoxic Growth of Poly-P Organisms
Conversion of Soluble Readily Biodegradable Chemical
Oxygen Demand to Short-Chain Fatty Acids
Under Aerobic Conditions
Sequestration of Short-Chain Fatty Acids by Poly-P Organisms
Nitrogen Source for Cell Synthesis
Growth of Non-Poly-P Heterotrophs on Short-Chain Fatty Acids
Hydrolysis/Solubilization of Slowly Biodegradable
Chemical Oxygen Demand
Decay of Poly-P Organisms under Anoxic Conditions
Conversion of Organic Nitrogen to Ammonia
Yield of Heterotrophs in Anoxic Growth
Switching Functions for Phosphorus Limitation
Releasable/Fixed Polyphosphate Components
General Dynamic Model for Nutrient Removal Systems
Model Component for Non-Poly-P Heterotrophs and Autotrophs
Model Component for Poly-P Heterotrophs
Evaluation and Calibration of the General Model
Simplified Steady-State Model
Date Required for the Steady-State Model
Steady-State Model Design Algorithm
Application of the Activated-Sludge Models
Application of the Activated-Sludge Models
Application of the General Model
Application of the Steady-State Model
Operating and System Parameters
Design Algorithm
Conclusion
References
8. Nutrient Removal by Aquatic Systems
Aquatic Systems
Ponds and Shallow Reservoirs
Wetland Systems
Main Components of Wetlands and Aquatic Systems
Hydrology
Soils/Substrate for Rooting Media
Vegetation
Physicochemical Characteristics
Nutrient Storage/Uptake Capacity of Aquatic Plants
Nutrient Removal Processes
Carbon Removal Processes
Aerobic Respiration
Facultative Anaerobic Respiration
Anaerobic Respiration
Nitrogen Removal Processes
Phosphorus Removal Processes
Design of Constructed Wetlands
Inflow/Outflow Concentrations
Hydraulic Retention Time
Hydraulic Loading Rate
Design Example
References
9. Testing and Evaluation of Full-Scale Nutrient Removal Facilities
Benefits of Full-Scale Testing
Limitations of Full-Scale Testing
Procedures for Conducting Full-Scale Testing
Testing Plan
Sampling Plan
Parameters of Interest
Sample Types and Locations
Schedule
Testing Facilities and Equipment
Process Control and Maintenance of Testing Conditions
Examples of Full-Scale Nutrient Removal Systems Testing
Suspended Growth
Nitrogen Removal Process Testing
Phosphorus Removal Process Testing
Combined Nitrogen and Phosphorus Process Testing
Fixed Film Processes
References
10. Costs for Nutrient Removal
Estimating Procedures
Factors
Implications of Design for Nutrient Control
Effect of Reaction Rate Safety Factors
Nitrification
Denitrification
Effect of Preaeration Anoxic Zones
Biological Versus Chemical Phosphorus Removal
Effect of Nutrient Removal (Long solids Retention Time Operation) on Aeration Power Costs
Selection of Optimum Mixed Liquor Suspended Solids Concentration
Effects of Seasonal Nutrient Removal on Capital and Operating Costs
Costs for Existing Biological Nutrient Removal Facilities
Survey
Capital Costs
Comparisons with Previous Work
Operations and Maintenance Costs
References
Appendix: Wastewater Characterization
Organic Material
Biodegradable and Nonbiodegradable Fractions
Biodegradable Subfractions
Nonbiodegradable Subfractions
Quantifying the Division
Nitrogenous Material
Free and Saline Ammonia and Organically
Bound Fractions
Biodegradable Organically Bound Total Kjeldahl Nitrogen
Nonbiodegradable Organically Bound Total Kjeldahl Nitrogen
Quantifying the Division
Phosphorus Content
Nitrification Rate
Measurement of Wastewater
Characteristics
Index