Efficiency of porous burnt-coke carrier on treatment of potato starch wastewater with an anaerobic–aerobic bioreactor

In the towns and countryside in the west of China, potato starch wastewater is an important source of water pollution as it is organic wastewater which is produced in high concentrations. The anaerobic–aerobic integrative baffled bioreactor is a new type of mobile equipment which is effective in the treatment of potato starch wastewater. In order to increase the efficiency of the anaerobic–aerobic integrative baffled bioreactor, porous burnt-coke particles, a waste product of heavy industry, were used as carriers in the aerobic pond to support the growth of microorganisms. Using this technique, the maximum reduction in chemical oxygen demand (COD) achieved was 98.7%, and the COD value in the effluent was less than 200 mg/L under the following operational conditions: pH 5.0–8.5 at 25–35 °C. The ammonium nitrogen (NH3–N) concentration in the wastewater was 10 mg/L and the use of burnt-coke removed 82.3% of this contaminant.