Application research of anoxic-aerobic biofilter on removing xanthate from beneficiation wastewater

Ore flotation had been widely employed in sulphide ores selection. However, large amount wastewater produced by flotation processes had caused major problem to mine environment. Biofiltration was a cost effective and environmental friendly technology combining biodegradation and physical scrubbing that had become an outstanding alternative for decentralized area wastewater treatment. In this study, a benchscale anoxic-aerobic biofilter was utilized to remove xanthate from synthetic beneficiation wastewater. Volcanic stone with diameter between 4mm to 6mm was applied as packing media for aerobic section. The objective of this study was to evaluate the performance of volcanic stone based biofilter for the treatment of xanthate. The running conditions were investigated to reach the maximum removal efficiency. Experimental data showed when HRT was 6h, air water flow ratio was 10/1 with an influent xanthate concentration below 250mg/L, the average COD removal efficiency was 88.7% and effluent COD concentration ranged 12mg/L to 43mg/L. The biofilter could well accustom to high pH influent while low pH influent would cause detrimental impact to biofilm and lead to system failure.