Study Of Treatment Of Alcohol Wastewater Using M-CASS Process

Following the industrial development, the short of water resource and the water pollution not only restrict the economic and social development in China, but also do harm to the health of people. As one of the major source of the water pollution, alcohol industry has discharged a large quantity of wastewater, which is an organic wastewater with the characteristics of high temperature and high concentrations. Thus it is quite important and practical significance to do research on the technique of alcohol industry wastewater treatment and reuse.In the light of the characteristics, the current treatment and the existing problems of alcohol wastewater, this article which based on the previous studies of the combined CASS and MBR in one structure, systematically study the running performance of integrated M-CASS process. The experimental results as follows: (1)When the M-CASS system was running stable, aeration modes had little effect on the removal of COD and NH3-N in CASS and the membrane system. The average removal rates of CASS system were all over 89% and 83%, and the average removal rates of membrane system were all over 94.8% and 85%. When intermittent aeration mode is adopted, the removal efficiency of TN from CASS and membrane was significantly better than the other two aeration modes, with the removal rates of 80.0% and 83.9%. The effluent of membrane was better than CASS all the time. (2) The removal rates of COD and NH3-N in M-CASS system were separately increased by 1.9% and 8.3% with Hydraulic Retention Time lengthened from 9.8h to 13h, and reached to 95.2% and 85%. But too long Hydraulic Retention Time will increase the project investment and operating costs. (3) The experiment remained the Hydraulic Retention Time at 13h by changing the cycle displacement. When alter the reaction period from 3h to 4h, the removal rate of COD and NH3-N in M-CASS system were separately increased by 0.8% and 1.4%, and reached to 96% and 86.4%. At the same time, it illustrated that if the Hydraulic Retention Time and other conditions remain unchanged, the removal effects of changing reaction period on the COD and NH3-N were little. After comprehensive comparison, the best result of pollutants removal and energy save could be obtained by the M-CASS reactor running under the conditions of intermittent aeration,13h's HRT and 4h's reaction period.Furthermore, the experiment was also carried out in the low temperature to study the pollutants removal efficiency of the CASS and M-CASS systems, observe and analyze the sedimentation performance of activated sludge.Finally, it gave a brief analysis and elaboration to the membrane fouling and cleaning appeared in the course of this experiment. It provided viable ideas for disposing and circulating alcohol industry wastewater.