Degradation of tetrachloroethylene by granular biological activated carbon under an anaerobic condition

Abstract

Various methods for the degradation of tetrachloroethylene (perchloroethylene, PCE) in wastewater have been reported. In this study, the effects of PCE removal under anaerobic conditions by granular activated carbon (GAC), anaerobic sludge and granular biological activated carbon (GBAC) were compared, and that GBAC was found to be the most effective of the above described three items. PCE was degraded as adsorption and biotransformation by GBAC. The experimental column (i.d 3 cm, height 55 cm) was packed with GBAC under anaerobic conditions, upflow. The GBAC was made from GAC and anaerobic sludge. The experimental temperatures ranging from 22- 24°C, nitrogen gas flow rate of 20 ml/min were used. PCE decreased because of microbial transformation and absorption of GAC, whose microbial activity signify much to decrease PCE during PCE was on the increase in the GAC. This paper made an approach to modeling of adsorptive process, and adsorptive capacity for single GBAC particle, and it was found that the adsorbed PCE degradated to many species which were reabsorbed on GBAC. This treatment method would maintain a higher removal effect for a long time.