Treatment of Munitions Decomposing Wastewater Using Membrane Biological Reactor

Abstract

Wastewater from the munitions decomposing process typically contains the widely used explosive-trinitrotoluene (TNT), which is also toxic and mutagenic. Commonly used technologies for degradation of TNT,such as activated carbon adsorption and chemical oxidation, are proved to be feasible but not cost-effective. In this study, the effectiveness of biodegradation of TNT by co-metabolism was evaluated in a hybrid hydrolysis acidification and aerobic membrane bioreactor. After six weeks acclimatization, over 90% TNT was removed with influent TNT concentration ranging between 70-85mg/L. Simultaneously remarkable MLSS concentration increase from 1.4 g/l to 6.9 g/l was observed, which indicated that the acclimatization and incubation of biomass was successful. The membrane effectively prevented loss of sludge and kept large biomass in the reactor, which made the system maintained in a high volume loading rate and low sludge loading rate. The experiment results showed that addition of carbon source was an essential factor in biodegradation of TNT wastewater.