Enhanced biodegradation of Reactive Violet 5R manufacturing wastewater using down flow fixed film bioreactor

The present study emphasizes on the development of bioprocess for biodegradation and bioremediation of Reactive Violet 5R (RV5) manufacturing industry’s wastewater in laboratory scale indigenously designed down flow fixed film bioreactor (DFFR). Process was investigated in DFFR, packed with furnace charcoal as a support material. During the batch and continuous operation of DFFR more than 95% degradation, 88% COD reduction and 99% copper remediation was obtained in less than 8 h of contact time. Continuous mode treatment gave degradation of more than 2500 mg dye in only 1 h of contact time. Addition of 0.25% peptone enhanced biodegradation rate more than three-fold. The biologically treated wastewater was found to stimulate the growth of selected soil bacteria. Degradation of major components of the wastewater was confirmed by HPTLC. DFFR was operated successfully for 750 d continuously, during which 716 cycles of batch treatment were operated.