การบำบัดน้ำเสียไบโอดีเซลโดยวิธีทางเคมีและทางชีวภาพ

Abstract

This research investigated the appropriate conditions for biodiesel wastewater treatment by chemical and biological treatment processes. In this study, initial concentrations of COD, oil and grease, methanol and glycerol of wastewater were 58,620, 2,300, 47,237 and 12, 750 mg/L, respectively. For chemical treatment process, polyaluminium chloride (PAC) and ionic polymers were applied as coagulant and coagulant aids, respectively, in order to evaluate appropriated types and dosage of coagulants and coagulant aids including effect of pH. It was found that the optimum condition was achieved at pH 4 with dosage of 20 gm/L cationic polymer or 62.5 mg/: PA?C and 1.25 mg/L cationic polymer, which had oil and grease removal percentage at 98 including COD, BOD, glycerol and methanol removal percentage at 38-41, 29-41, 16-23, and 25-33, respectively. For biological treatment process, wastewater treated by chemical treatment process using above optimu condition was investigated for evaluating biodegradation efficiency under aerobic and anaerobic conditions. Initial COD concentrations for aerobic treatment were 2,000 and 3.000 mg/L. Furthermore, initial COD concentrations for anaerobic treatment were set at 3,500, 5,200 and 8.000 mg/L. It was found that suitable initial COD concentration for aerobic biodegradation was 3,000 mg/L and COD concentration at effluent standard (Department of Industrial Work) could be reached within 4 day. COD, filtrated COD and methanol removal efficiencies were 93, 96 and 96 percent, respectively. However, suitable initial COD concentration for anaerobic biodegradation should be lower than 5,200 mg/L and COD concentration at wastewater standard could be reached within 13 day. COD, filtrated COD and methanol removal efficiencies were 98, 99 and 98 percent, respectively.