Biodegradation of trichloroethylene in a rotating biological contactor

A laboratory scale study was carried out to treat synthetic wastewater containing 30 mg/l of trichloroethylene in a rotating biological contactor (RBC). A mixed culture of bacteria consisting of nitrifiers, heterotrophs and Thiosphaera pantotropha could be developed and acclimated to achieve 99.89% removal of trichloroethylene (TCE) from synthetic wastewater at TCE loading of 0.0039 m3/m2 d and HRT of 3.5 days. A substrate: CO substrate ratio of 1:100 and above was found to be optimum to avoid enzyme competition. C:N ratio of 100:20 was optimum for the biodegradation of TCE. The system could withstand TCE shock loadings up to 0.309 m3/m2 d. The volatilization losses of TCE were 4.8% from the RBC unit.