6.2 Low-Rate, High-Rate, and Super-Rate Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
6.3 Single- and Multi-stage Trickling Filter Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
7 Performance Models and Design Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
7.1 National Research Council Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
7.2 Velz Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
7.3 Upper Mississippi River-Great Lakes Board Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
7.4 Howland Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
7.5 Eckenfelder Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
7.6 Galler and Gotaas Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
7.7 Biofilm Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
7.8 US Army Design Formulas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
7.9 US Environmental Protection Agency Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
8 Design and Construction Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
9 Recent Advances in Biological Waste Treatment Processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
Abstract Current practice in the secondary treatment of wastewater for pollution
control calls for the use of biological oxidation to remove organic substances. When
it comes to selecting the method of biological oxidation, a pollution control engineer
has at his or her disposal a variety of treatment processes, among which activated
sludge and trickling filters are the most popular. The function and limitations of the
activated sludge processes are reviewed. The principles of biological oxidation and
of the energy flow concept are described, and the relationship of synthesis and
respiration is discussed in relation to the importance of activated sludge process
control.
A contact bed, contact aerator, trickling filter, rotating disks, or other attachedgrowth systems consist of a bed of coarse contact media such as granite, limestone,
clinkers, wood slats, plastic tubes, corrugated plastic sections, hard coal, or other
material over which wastewater is distributed or contacted. Wastewater flows over
the contact media on which a biological slime layer develops. Dissolved organic
pollutants in the wastewater are transported into the slime layer, where biological
oxidation takes place. Organic pollutants are removed by the biological slime film,
which consists of various microorganisms. In the outer portions of the film, organic
pollutants are degraded by aerobic and facultative bacteria. Transfer of oxygen in
slime layer and liquid film, transfer of substrate in liquid film and slime layer, types
of trickling filters, performance models, and design procedures are discussed. This
book chapter also introduces recent advances in biological wastewater treatment
processes involving the use of dissolved air flotation for primary flotation clarification, secondary flotation clarification, tertiary flotation clarification, flotation
sequencing batch reactor, and flotation sludge thickening.
Keywords Biological treatment · Biological oxidation · Activated sludge ·
Trickling filters · Zoogleal slime film · Synthesis · Respiration · Attached-growth
system · Models · Design · Dissolved air flotation · Primary flotation clarification ·
Secondary flotation clarification · Tertiary flotation clarification · Flotation sludge
thickening · Flotation sequencing batch reactor
74
L. K. Wang et al.
6.3 Single- and Multi-stage Trickling Filter Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
7 Performance Models and Design Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
7.1 National Research Council Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
7.2 Velz Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
7.3 Upper Mississippi River-Great Lakes Board Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
7.4 Howland Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
7.5 Eckenfelder Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
7.6 Galler and Gotaas Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
7.7 Biofilm Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
7.8 US Army Design Formulas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
7.9 US Environmental Protection Agency Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
8 Design and Construction Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
9 Recent Advances in Biological Waste Treatment Processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
Abstract Current practice in the secondary treatment of wastewater for pollution
control calls for the use of biological oxidation to remove organic substances. When
it comes to selecting the method of biological oxidation, a pollution control engineer
has at his or her disposal a variety of treatment processes, among which activated
sludge and trickling filters are the most popular. The function and limitations of the
activated sludge processes are reviewed. The principles of biological oxidation and
of the energy flow concept are described, and the relationship of synthesis and
respiration is discussed in relation to the importance of activated sludge process
control.
A contact bed, contact aerator, trickling filter, rotating disks, or other attachedgrowth systems consist of a bed of coarse contact media such as granite, limestone,
clinkers, wood slats, plastic tubes, corrugated plastic sections, hard coal, or other
material over which wastewater is distributed or contacted. Wastewater flows over
the contact media on which a biological slime layer develops. Dissolved organic
pollutants in the wastewater are transported into the slime layer, where biological
oxidation takes place. Organic pollutants are removed by the biological slime film,
which consists of various microorganisms. In the outer portions of the film, organic
pollutants are degraded by aerobic and facultative bacteria. Transfer of oxygen in
slime layer and liquid film, transfer of substrate in liquid film and slime layer, types
of trickling filters, performance models, and design procedures are discussed. This
book chapter also introduces recent advances in biological wastewater treatment
processes involving the use of dissolved air flotation for primary flotation clarification, secondary flotation clarification, tertiary flotation clarification, flotation
sequencing batch reactor, and flotation sludge thickening.
Keywords Biological treatment · Biological oxidation · Activated sludge ·
Trickling filters · Zoogleal slime film · Synthesis · Respiration · Attached-growth
system · Models · Design · Dissolved air flotation · Primary flotation clarification ·
Secondary flotation clarification · Tertiary flotation clarification · Flotation sludge
thickening · Flotation sequencing batch reactor
74
L. K. Wang et al.