Study On The Wastewater Treatment Of Freeway Affiliated Facility By Biological Contact Oxidation Process

In view of the wastewater treatment problems from expressway affiliated facilities in our country, a BCO (Biological Contact Oxidation) process was tested in treatment of the peculiar with the expectation of providing a technical support to the engineers. During the experimental period, the performance of the process was studied from the aspect of HRT(hydraulic retention time), influent constituents, influent mode, technical economy and the degradation rate of COD and nitrogen nutriment, etc. The dynamics model of the BCO process dealing with the sewage was analyzed in condition of the test.Through the results of the test we could conclude as follows: (1) The reactor filled with filler, made by hog hair, possessed a fast velocity of bio-film domestication, a rapid shape up period and excess biomass; (2) When the reactor was operated in the mode of continuous influent and continuous aeration, with the HRT of 4h, 6h, 10h, 14h, 16h and 20h respectively, the removment of COD and Ammonia Nitrogen at HRT=6h was greater than 80% and 45% , the COD and Ammonia Nitrogen of effluent were less than 100mg/L and 12.1mg/L respectively, which can achieve the first class of Integrated Wastewater Discharge Standard (GB8978-1996) ; (3) Under the constant influent, the reactor was operated in those two intermittent modes of 3 times influent and 3, 6, 9, 12, 24 times aeration a day (once an hour) and 6 times influent and 9, 12, 15, 18, 24 times aeration a day (once an hour). When the influent was characterized by 3 times a day, 6 hours of cumulative baric retention time, the effluent values of COD, Ammonia Nitrogen and TN were 72 mg/L,6.5 mg/L and 16.3 mg/L respectively; and that by 6 times a day, 12 hours of cumulative baric retention time, the effluent values of COD, Ammonia Nitrogen and TN were 78 mg/L, 6.4mg/L and 16.0mg/L respectively. The effluents for both of the two operating models can achieve the first class of Integrated Wastewater Discharge Standard (GB8978-1996) ; (4) Based on the test results, the dynamics model of the BCO reactor was proposed as:U =(14.2×(S_e-46.2))/(49.5 + (S_e- 46.2)), with correlation coefficient R being 0.9575. The curve of...