| |
| |
| |
Solids Separation Problems | |
| |
| |
| |
Introduction | |
| |
| |
| |
Solids Separation Problems | |
| |
| |
| |
Activated Sludge Floc | |
| |
| |
| |
Solids Separation Problems in Terms of Floc Structure | |
| |
| |
| |
Dispersed Growth | |
| |
| |
| |
Viscous Bulking | |
| |
| |
| |
Pin Floc | |
| |
| |
| |
Filamentous Bulking | |
| |
| |
| |
Foam/Scum | |
| |
| |
| |
Differentiation of Microbial and Process-Related Solids Separation Problems | |
| |
| |
| |
Methods | |
| |
| |
| |
Introduction | |
| |
| |
| |
Microscopic Examination Methods | |
| |
| |
| |
Filament Counting Methods | |
| |
| |
| |
Total Extended Filament Length | |
| |
| |
| |
Filament Count | |
| |
| |
| |
Nocardioform Filament Organism Counting | |
| |
| |
| |
Floc and Filamentous Microorganism Characterization | |
| |
| |
| |
Introduction | |
| |
| |
| |
Sampling Points | |
| |
| |
| |
Sampling Frequency | |
| |
| |
| |
Sample Transport and Storage | |
| |
| |
| |
Microscope | |
| |
| |
| |
Cameras | |
| |
| |
| |
Staining Procedures | |
| |
| |
| |
Sample Preparation | |
| |
| |
| |
Floc Characteristics and Overall Filament Abundance | |
| |
| |
| |
Floc Size | |
| |
| |
| |
Floc Characteristics | |
| |
| |
| |
Protozoa and Other Macroorganisms | |
| |
| |
| |
Nonbiological Organic and Inorganic Particles | |
| |
| |
| |
Bacterial Colonies | |
| |
| |
| |
Cells Dispersed in Bulk Solution | |
| |
| |
| |
Effects of Filamentous Organisms on Floc Structure | |
| |
| |
| |
Filamentous Organism Abundance | |
| |
| |
| |
Filamentous Organism Characteristics | |
| |
| |
| |
Branching | |
| |
| |
| |
Motility | |
| |
| |
| |
Filament Shape | |
| |
| |
| |
Location | |
| |
| |
| |
Attached Bacteria | |
| |
| |
| |
Sheath | |
| |
| |
| |
Cross-Walls (Cell Septa) | |
| |
| |
| |
Filament Width | |
| |
| |
| |
Filament Length | |
| |
| |
| |
Cell Shape | |
| |
| |
| |
Cell Size | |
| |
| |
| |
Sulfur Deposits | |
| |
| |
| |
Other Granules | |
| |
| |
| |
Staining Reactions | |
| |
| |
| |
Additional Observations | |
| |
| |
| |
Filamentous Organism Identification | |
| |
| |
| |
Using the Dichotomous Key | |
| |
| |
| |
Building Your Skills | |
| |
| |
| |
Filamentous Organism Descriptions | |
| |
| |
| |
Sphaerotilus natans (Figures 2.9c, 2.13b, 2.14f, and 2.21a) | |
| |
| |
| |
Type 1701 (Figure 2.21b) | |
| |
| |
| |
Haliscomenobacter hydrossis (Figure 2.21c) | |
| |
| |
| |
Type 021N (Figures 2.11b, 2.13d, 2.14d, 2.14e, 2.15c, 2.18a, 2.19b, and 2.22a) | |
| |
| |
| |
Thiothrix I (Figures 2.14b, 2.15a, 2.19c, and 2.23a) | |
| |
| |
| |
Thiothrix II (Figures 2.19d, 2.23c, and 2.23d) | |
| |
| |
| |
Type 0914 (Figures 2.15d, 2.24a, and 2.24b) | |
| |
| |
| |
Beggiatoa sp. (Figures 2.15b, 2.22c, and 2.22d) | |
| |
| |
| |
Nostocoida limicola I (Figure 2.25a) | |
| |
| |
| |
Nostocoida limicola II (Figures 2.10e, 2.11c, 2.17b, 2.18e, and 2.25b) | |
| |
| |
| |
Nostocoida limicola III (Figure 2.25c) | |
| |
| |
| |
Type 0411 (Figure 2.26a) | |
| |
| |
| |
Type 0961 (Figure 2.26b) | |
| |
| |
| |
Type 0092 (Figures 2.18d and 2.26c) | |
| |
| |
| |
Type 0581 (Figure 2.26d) | |
| |
| |
| |
Type 0041 (Figures 2.10a, 2.12a, 2.13c, 2.14a, 2.17c, 2.18f, and 2.27a) | |
| |
| |
| |
Type 0675 (Figure 2.27b) | |
| |
| |
| |
Type 1851 (Figures 2.17d and 2.27c) | |
| |
| |
| |
Type 0803 (Figure 2.27d) | |
| |
| |
| |
Microthrix parvicella (Figures 2.17e, 2.18c, 2.28a, 5.1e, and 5.1f) | |
| |
| |
| |
Nocardioforms (Figures 2.9b, 2.10f, 2.14g, 2.17f, 2.18b, 2.28b, 5.1a, 5.1b, 5.1c and 5.1d) | |
| |
| |
| |
Type 1863 (Figures 2.10c, 2.14c, and 2.28c) | |
| |
| |
| |
Type 0211 (Figure 2.28d) | |
| |
| |
| |
Flexibacter sp. (Figure 2.29a) | |
| |
| |
| |
Bacillus sp. (Figure 2.29b) | |
| |
| |
| |
Cyanophyceae (Figure 2.29c) | |
| |
| |
| |
Fungi (Figures 2.9a and 2.29d) | |
| |
| |
| |
Progress in Identifying Filamentous Organisms | |
| |
| |
| |
Protozoa And Metazoa | |
| |
| |
| |
General | |
| |
| |
| |
Microscopic Evaluation | |
| |
| |
| |
Taxonomic Classification | |
| |
| |
| |
Flagellates | |
| |
| |
| |
Amoebae | |
| |
| |
| |
Free-Swimming Ciliates | |
| |
| |
| |
Attached Ciliates | |
| |
| |
| |
Rotifers | |
| |
| |
| |
Higher Invertebrates | |
| |
| |
| |
Use of Protozoa and Metazoa as Indicator Organisms | |
| |
| |
| |
Physical and Chemical Methods | |
| |
| |
| |
Settling Tests | |
| |
| |
| |
Foaming Tests | |
| |
| |
| |
Methods for Differentiating Microbiological and Process-Related Solids Separation Problems | |
| |
| |
| |
Dispersed SS (DSS) | |
| |
| |
| |
Flocculated SS (FSS) | |
| |
| |
| |
Secondary Effluent SS (ESS) | |
| |
| |
| |
Applications and Results of Microscopic Examination of Activated Sludge | |
| |
| |
| |
Introduction | |
| |
| |
| |
Filament Counting | |
| |
| |
| |
Filamentous Organism Identification in Activated Sludge | |
| |
| |
| |
Results of Filamentous Organism Surveys | |
| |
| |
| |
Diagnosis of Causes of Solids Separation Problems through Microscopic Examination | |
| |
| |
| |
General | |
| |
| |
| |
Nonmicrobial Particles | |
| |
| |
| |
Other Microbiological Features | |
| |
| |
| |
General | |
| |
| |
| |
Limited Diversity | |
| |
| |
| |
Dispersed Growth | |
| |
| |
| |
Neisser-Positive Cell Clumps | |
| |
| |
| |
Yeast | |
| |
| |
| |
Zoogloeas | |
| |
| |
| |
Selector Flocs | |
| |
| |
| |
Nitrifying Bacteria | |
| |
| |
| |
Denitrifying Bacteria | |
| |
| |
| |
Spirochaetes, Spirillum, and Flexibacter | |
| |
| |
| |
Exocellular Material | |
| |
| |
| |
Algae | |
| |
| |
| |
Filamentous Organisms | |
| |
| |
| |
Relationship to Causes of Bulking | |
| |
| |
| |
Nutrient Balance | |
| |
| |
| |
Readily Metabolizable Soluble Organics | |
| |
| |
| |
Sulfide | |
| |
| |
| |
Lipids | |
| |
| |
| |
Other Particulate Substrates | |
| |
| |
| |
Case Study | |
| |
| |
| |
Net Growth Rate (MCRT, F/M) | |
| |
| |
| |
Aeration Basin Configuration and Redox Conditions | |
| |
| |
| |
Wastewater Feeding Regime | |
| |
| |
| |
Foam Trapping Features | |
| |
| |
| |
Upstream Biological Treatment Units, Sewer Surfaces, and In-Plant Surfaces | |
| |
| |
| |
DO Concentration | |
| |
| |
| |
pH | |
| |
| |
| |
Temperature | |
| |
| |
| |
Summary | |
| |
| |
| |
Control of Activated Sludge Bulking and Other Settling Problems | |
| |
| |
| |
Introduction | |
| |
| |
| |
General Approach | |
| |
| |
| |
Rapid, Nonspecific Bulking Control Methods | |
| |
| |
| |
Manipulation of RAS Flow Rates and Aeration Basin Feed Points | |
| |
| |
| |
Secondary Clarifier Operating Principles | |
| |
| |
| |
Activated Sludge Process Schematic and Definitions | |
| |
| |
| |
Secondary Clarifier Process Operating Relationships | |
| |
| |
| |
Degree of Thickening Achieved by Secondary Clarifier | |
| |
| |
| |
Required RAS Flow Rate | |
| |
| |
| |
Secondary Clarifier Capacity | |
| |
| |
| |
Sludge Thickening Theory | |
| |
| |
| |
Secondary Clarifier Analysis and Operation | |
| |
| |
| |
System Analysis and Operation | |
| |
| |
| |
Addition of Chemicals and Inert Solids to Enhance Activated Sludge Settling Rates | |
| |
| |
| |
Addition of Disinfectants to Selectively Kill Filamentous Organisms | |
| |
| |
| |
General | |
| |
| |
| |
Use of Chlorination for Bulking Control | |
| |
| |
| |
Chlorination Criteria | |
| |
| |
| |
General Guidelines | |
| |
| |
| |
Chlorination System Design | |
| |
| |
| |
Monitoring Effects of Chlorine Addition | |
| |
| |
| |
Case Histories of Bulking Control Using Chlorination | |
| |
| |
| |
General | |
| |
| |
| |
City of Albany, GA | |
| |
| |
| |
City of San Jose/Santa Clara Water Pollution Control Plant, CA | |
| |
| |
| |
Stroh Brewing Co., Longview, TX | |
| |
| |
| |
Plastics Manufacturing Wastewater Activated Sludge System, WV | |
| |
| |
| |
Use of Hydrogen Peroxide for Bulking Control | |
| |
| |
| |
General | |
| |
| |
| |
City of Petaluma, CA | |
| |
| |
| |
Use of Ozone for Bulking Control | |
| |
| |
| |
Filamenticides | |
| |
| |
| |
Specific Methods of Bulking Control | |
| |
| |
| |
Nutrient Deficiency | |
| |
| |
| |
General | |
| |
| |
| |
Macronutrient Deficiency | |
| |
| |
| |
General | |
| |
| |
| |
Factors Affecting Macronutrient Requirements | |
| |
| |
| |
Availability of Macronutrients | |
| |
| |
| |
Satisfying Macronutrient Demands | |
| |
| |
| |
Required Residual Macronutrient Concentrations | |
| |
| |
| |
Micronutrients | |
| |
| |
| |
Low Dissolved Oxygen (DO) Concentrations | |
| |
| |
| |
General | |
| |
| |
| |
Case Histories | |
| |
| |
| |
Orange County Sanitation District Plant, Fountain Valley, CA | |
| |
| |
| |
Pulp and Paper Wastewater Activated Sludge Plant | |
| |
| |
| |
City of Woonsocket, RI | |
| |
| |
| |
Effect of Aeration Basin Configuration, Wastewater Feeding Method, and Redox Conditions on Activated Sludge Settling Characteristics | |
| |
| |
| |
Effect of Aeration Basin Configuration | |
| |
| |
| |
Selectors | |
| |
| |
| |
Selector Effect | |
| |
| |
| |
General Observations | |
| |
| |
| |
Selector Mechanisms | |
| |
| |
| |
Effects of Selectors | |
| |
| |
| |
Selector Design (Sizing) | |
| |
| |
| |
General | |
| |
| |
| |
Initial Contact Zones | |
| |
| |
| |
Aerobic Selectors | |
| |
| |
| |
Anoxic Selectors | |
| |
| |
| |
Anaerobic Selectors | |
| |
| |
| |
Main Aeration Basin | |
| |
| |
| |
Selector Case Histories | |
| |
| |
| |
Leopoldsdorf Sugar Mill, Austria | |
| |
| |
| |
Hamilton, OH | |
| |
| |
| |
Davenport, IA | |
| |
| |
| |
Tri-City, Clackamas County, OR | |
| |
| |
| |
Fayetteville, AR | |
| |
| |
| |
Hyperion Treatment Plant, Los Angeles, CA | |
| |
| |
| |
23rd Avenue Plant, Phoenix, AZ | |
| |
| |
| |
Situations Where Selectors Are Not Effective | |
| |
| |
| |
High Effluent SS Due to Clarification Problems | |
| |
| |
| |
General | |
| |
| |
| |
Problem Definition | |
| |
| |
| |
Method of Investigation | |
| |
| |
| |
Results | |
| |
| |
| |
Problem Resolution | |
| |
| |
| |
Inadequate Flocculation, Floc Break-Up (High ESS, High DSS[subscript i], Low FSS) | |
| |
| |
| |
Clarifier Hydraulic Problems (High ESS, Low DSS, Low FSS) | |
| |
| |
| |
Bioflocculation Problems (High DSS[subscript i], High FSS, High ESS) | |
| |
| |
| |
Activated Sludge Foaming and Control | |
| |
| |
| |
Activated Sludge Foaming | |
| |
| |
| |
Types of Activated Sludge Foam | |
| |
| |
| |
Nocardioform Foaming | |
| |
| |
| |
Extent and Significance of Problems | |
| |
| |
| |
Foaming Organism Surveys | |
| |
| |
| |
Foaming Problems | |
| |
| |
| |
Activated Sludge | |
| |
| |
| |
Anaerobic Digesters | |
| |
| |
| |
Pathogenic Nocardioforms | |
| |
| |
| |
Proposed Mechanisms of Foaming | |
| |
| |
| |
Introduction | |
| |
| |
| |
Physical/Chemical Factors | |
| |
| |
| |
Nature of Foam | |
| |
| |
| |
Solids-Containing Foams | |
| |
| |
| |
Roles of Surfactants | |
| |
| |
| |
Anaerobic Digester Foaming | |
| |
| |
| |
Foam Trapping and Recycling | |
| |
| |
| |
Foaming Tests | |
| |
| |
| |
Microbiological Factors | |
| |
| |
| |
Factors Affecting Growth | |
| |
| |
| |
MCRT and Temperature | |
| |
| |
| |
pH | |
| |
| |
| |
Nocardioform Control | |
| |
| |
| |
Nocardioform Growth in Activated Sludge | |
| |
| |
| |
Introduction | |
| |
| |
| |
Aerobic Selectors | |
| |
| |
| |
Anoxic Selectors | |
| |
| |
| |
Anaerobic Selectors | |
| |
| |
| |
Classifying Selectors and Selective Foam Wasting | |
| |
| |
| |
Chlorination | |
| |
| |
| |
Cationic Polymer Addition | |
| |
| |
| |
Automatic MCRT Control | |
| |
| |
| |
Microthrix parvicella | |
| |
| |
| |
Factors Affecting M. parvicella Growth | |
| |
| |
| |
General | |
| |
| |
| |
Substrates | |
| |
| |
| |
Operating Conditions | |
| |
| |
| |
Control | |
| |
| |
| |
Case Histories | |
| |
| |
| |
Upper Occoquan Sewage Authority (UOSA), VA | |
| |
| |
| |
Northside Wastewater Treatment Plant, Tulsa, OK | |
| |
| |
| |
Anaerobic Digester Foaming | |
| |
| |
Bibliography and References | |
| |
| |
Index | |