Sequencing Batch Reactor (SBR)
The Sequencing Batch Reactor (SBR) is a fill-and-draw, non-steady state activated sludge process
in which one or more reactor basins are filled with wastewater during a discrete time period, and
then operated in a batch treatment mode. The SBR accomplishes equalization, aeration and clarification
in a timed sequence, in a single reactor basin, whereas a conventional continuous flow process requires
multiple structures and extensive pumping and piping systems. A single cycle for each reactor consists
of five discrete periods, Fill, React, Settle, Draw, and Idle. The purpose of each period is described
in the illustrations below.
Varying the operating strategy enables aerobic, anaerobic or anoxic conditions to be achieved. Precise
control of these conditions allows Organism Selection to take place--the proliferation of specific
desireable microorganisms is encouraged, while the growth of undesireable mircoorganisms is inhibited.
Microorganisims can also be acclimated to a wide range of industrial and chemical processing wastes.
Anoxic Fill Phase:
The reactor is filled with wastewater. Fill can be aerated, anoxic, or a combination
of aerated and anoxic. Biodegradation is intiated.
During Anoxic Fill, influent is distributed throughout the settled sludge
through the influend distribution manifold. Pumps are not operated, no power is used. Influent
is not diluted by mixing, making biological nutrient removal much more reliable.