hopper at one end, either by scrapers called “flights” set on parallel chains or by a
single bottom scraper set on a traveling bridge. In a circular sedimentation
clarifier, the wastewater usually enters in the middle and flows toward the outside
edge. Settled sludge is pushed to the hopper that is in the middle of the circular
clarifier’s tank bottom.
Secondary treatment: It is a wastewater treatment step after primary treatment
(either primary sedimentation clarification or primary flotation clarification).
Secondary treatment may be either biological treatment (such as activated sludge
aeration plus secondary clarification) or physicochemical treatment (such as
chemical precipitation/coagulation plus secondary clarification) mainly for
removing dissolved organic/inorganic pollutants from primary effluent.
Selector hydraulic retention time (HRT): The given time it takes wastewater,
including any return flows, to pass through a tank (selector).
Selector: A zone in a biological treatment process with specific environmental
conditions that allow for the growth or lack of growth of certain microorganisms
(such as an anoxic or anaerobic zone).
Sequencing batch exchanger (SBE): A sequencing batch process involving the
use of separate batch process steps in sequence of filling water/wastewater,
reacting with ion exchanger, settling insoluble spent ion exchanger, discharging
treated effluent, and recycling the settled spent ion exchanger for regeneration,
resulting in removing ionic pollutants from water or wastewater (US Patent
5354458).
Sequencing batch flotation (SBF): A sequencing batch process (either biological
or physicochemical) involving the use of separate batch process steps in sequence
of filling water/wastewater, reacting with chemicals or biomass, floating lightweight insoluble flocs and/or biomass, discharging treated effluent, and wasting
floated insoluble scums for water or wastewater treatment is also called sequencing batch flotation (SBF) process (US Patent 5354458).
Sequencing batch reactor (SBR), biological: A biological SBR system performs
all the necessary functions of carbonaceous and nutrient removals in a single tank
with variable water levels and timed aerobic aeration or anoxic mixing. This SBR
system requires a minimum of three tanks and advanced automation equipment to
control the cycle times and phases. The SBR control systems allows the operation
to be configured to operate as almost any other suspended-growth biological
reactor by adjusting the cycle phases between fill phase, react phase (either
aerobic aeration or anoxic mixing), separation phase (either sedimentation or
flotation), and decant phase. The biological SBR system involving the use of
flotation in the separation phase is invented by Dr. Lawrence K. Wang,
Dr. Lubomyr Kurylko, and Dr. Mu-Hao Sung Wang in 1994 (US Patent
5354458).
Sequencing batch reactor (SBR), physicochemical: A physicochemical SBR
system performs all the necessary functions of organic and inorganic pollutants
removals in a single tank with variable water levels and timed mixing, coagulation/flocculation or clarification (either sedimentation or flotation). This SBR
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L. K. Wang et al.
single bottom scraper set on a traveling bridge. In a circular sedimentation
clarifier, the wastewater usually enters in the middle and flows toward the outside
edge. Settled sludge is pushed to the hopper that is in the middle of the circular
clarifier’s tank bottom.
Secondary treatment: It is a wastewater treatment step after primary treatment
(either primary sedimentation clarification or primary flotation clarification).
Secondary treatment may be either biological treatment (such as activated sludge
aeration plus secondary clarification) or physicochemical treatment (such as
chemical precipitation/coagulation plus secondary clarification) mainly for
removing dissolved organic/inorganic pollutants from primary effluent.
Selector hydraulic retention time (HRT): The given time it takes wastewater,
including any return flows, to pass through a tank (selector).
Selector: A zone in a biological treatment process with specific environmental
conditions that allow for the growth or lack of growth of certain microorganisms
(such as an anoxic or anaerobic zone).
Sequencing batch exchanger (SBE): A sequencing batch process involving the
use of separate batch process steps in sequence of filling water/wastewater,
reacting with ion exchanger, settling insoluble spent ion exchanger, discharging
treated effluent, and recycling the settled spent ion exchanger for regeneration,
resulting in removing ionic pollutants from water or wastewater (US Patent
5354458).
Sequencing batch flotation (SBF): A sequencing batch process (either biological
or physicochemical) involving the use of separate batch process steps in sequence
of filling water/wastewater, reacting with chemicals or biomass, floating lightweight insoluble flocs and/or biomass, discharging treated effluent, and wasting
floated insoluble scums for water or wastewater treatment is also called sequencing batch flotation (SBF) process (US Patent 5354458).
Sequencing batch reactor (SBR), biological: A biological SBR system performs
all the necessary functions of carbonaceous and nutrient removals in a single tank
with variable water levels and timed aerobic aeration or anoxic mixing. This SBR
system requires a minimum of three tanks and advanced automation equipment to
control the cycle times and phases. The SBR control systems allows the operation
to be configured to operate as almost any other suspended-growth biological
reactor by adjusting the cycle phases between fill phase, react phase (either
aerobic aeration or anoxic mixing), separation phase (either sedimentation or
flotation), and decant phase. The biological SBR system involving the use of
flotation in the separation phase is invented by Dr. Lawrence K. Wang,
Dr. Lubomyr Kurylko, and Dr. Mu-Hao Sung Wang in 1994 (US Patent
5354458).
Sequencing batch reactor (SBR), physicochemical: A physicochemical SBR
system performs all the necessary functions of organic and inorganic pollutants
removals in a single tank with variable water levels and timed mixing, coagulation/flocculation or clarification (either sedimentation or flotation). This SBR
156
L. K. Wang et al.