SBRs

Sequencing batch reactors (SBRs) have been around for a long time. They were operating successfully long before flow-through, activated sludge systems were designed. In flow-based systems, variables in the flow can cause upsets and incomplete treatment. Because the SBR process is time-based rather than flow-based, there is much more control of the treatment process—both in multiple and single tank systems.

Here’s what the E.P.A. has to say:

The SBR process has widespread application where mechanical treatment of small wastewater flows is desired. Because it provides batch treatment...it is ideally suited for...wide variations in flow rates...operation in the “fill and draw” mode prevents the “washout” of biological solids that often occurs with extended aeration systems.... Another advantage of SBR systems...is that they require less operator attention yet...produce a very high quality effluent.*

ENTEX has successfully converted SBRs using fixed media BioWeb system at National Pingtung University, Taiwan.