Application of full scale moving bed biofilm reactor in the adanced treatment of petrochemical secondary wastewater

摘要

On the basis of the laboratory scale experiment and the full scale operation, this paper investigated the start-up and operation characteristics of the Moving bed biofilm reactor (MBBR) on advanced treatment of petrochemical secondary wastewater of Fushun Ethylene Company Limited. The effect of volume loading rate on COD removal and the effect of suspended sludge on biofilm was also studied. The experimental results have suggested that the starting-up of the closed-circuit method was slower than that of the sludge eliminating method, but the former had better removal result than the latter. There existed inhibiting relationship between the suspended sludge produced in the operation of MBBR and the biofilm on the carrier, which was harmful to the long and stable operation of the reactor.Under the conditions of the hydraulic retention time to 1.3h and the ratio of gas flow to liquid flow of 4:1, the removal rates of COD and NH4-N was about 80% and 90%, respectively.