As a fill and draw or
batch process, all biological treatment phases occur in a single tank. This differs from the conventional flow through activated sludge process in that SBRs
do not require separate tanks for aeration and
sedimentation (Kappe, 1999). SBR systems contain
either two or more reactor tanks that are operated in
parallel, or one equalization tank and one reactor
tank. The type of tank used depends on the
wastewater flow characteristics (e.g. high or low
volume). While this setup allows the system to
accommodate continuous influent flow, it does not
provide for disinfection or holding for aerated
sludge.