Experimental research on treatment of low level methanol wastewater with immobilized microbiology

15 strains methanol degradation engineering bacteria were obtained under aerobic conditions from the aeration pond of Daqing fertilizer factory and then screened, acclimatized, and immobilized on granular activated carbon to form bio-reactors, and pilot-scale studies were conducted to investigate such factors as different absorbed supports, pH, temperature, dissolved oxygen (DO), methanol concentration and hydraulic retention time, affecting effectiveness of the treatment. Experimental results indicate that methanol removal is 70% at least when pH is 7.0-8.5, temperature is 25-35°C, DO is 3-5 mg/L, hydraulic retention time is 30 min and concentration is 15-35 mg/L. The effluent concentrations of COD were not more than 12 mg/L, and could be used in the desalination system and then wastewater could be reused in an industrial boiler.