Abstract: Organic components such as Chlorobenzene (CB) was detected in the water source for artificial recharge which was planned to control regional land subsidence. As artificial recharge will disturb the underground environment, recharge in different seasons will lead to variations of underground temperature and dissolved oxygen. In view of this, the authors mainly investigated the biodegradation of CB in different underground environments during artificial recharge. Data from pilot-scale biodegradation experiments in laboratory showed that the biodegradation of CB well fitted the first-order kinetics of decay and the Monod equations at certain concentration. It was obtained through Monod equation that when temperature and dissolved oxygen raised, the reaction rates of degradation accelerated, and thus the biodegradation effect was better. The Arrhenius equation could quantify the impact of temperature on the biodegradation rate. With different CB concentrations, the calculated maximum amount of biodegradation in aerobic and anaerobic conditions at 20℃,10℃,0℃ were 35, 31, 28 μg/g and 30, 27, 23 μg/g respectively. It's concluded that the best season for artificial recharge is summer owing to the influence of temperatures and dissolved oxygen on CB biodegradation.

Key words: Chlorobenzene (CB), biodegradation, artificial recharge, groundwater