An Application of Sequencing Batch Reactors in Microbial Degradation of Benzene, Toluene & Xylene under Anoxic and Micro Aerobic Condition

Abstract

This paper mainly focuses on treatment process for Benzene, Toluene & Xylene (BTX) containing wastewater by using an alternating anoxic/micro aerobic sequencing batch reactor to overcome the stripping of BTX compounds into the atmosphere, as often occurs in conventional aerobic treatment processes. An ORP probe was successfully used to monitor different electron acceptor conditions in sequencing batch reactors whereas a DO probe failed to detect the low DO concentration under micro aerobic conditions. Toluene and m-xylene were amenable to anoxic (denitrifying) metabolism while benzene, o-, and p-xylene were biodegradable under micro aerobic conditions. Compared to conventional aerobic treatment processes, this approach can eliminate vigorous aeration and significantly reduce stripping of BTX (and other volatile contaminants amenable to anoxic/micro aerobic biodegradation) caused by aeration.