| Vinylon is one kind of chemical material with stabilized property, industrially applied widespread but difficultly biodegraded. The BOD5/COD of vinylon wastewater is from 0.01 to 0.04, the efficiency of conventional biological treatment is very low. This kind of material, which is difficult to be biodegraded can be accumulated in the environment and results in the environmental pollution. The objective of this paper is to treat vinylon waste water specifically for Shandong Kingshore Group.Iron coal +hydrogen peroxide strengthened micro-electrolysis method and anoxic denitrification have been chosen as the pretreatment experiment, in order to raise the biochemistry of the vinylon waste water. Iron filings and pellet charcoal treated with the ratio of 15:1 (apparent volume of 1:1) had been mixed homogeneously, the COD of inflent being controlled about 1500mg/L. The effect of pH, the reaction time and the concentration of H2O2 on COD removing efficiency were investigated. Under the optimized process conditions, the pH 3.0, reaction time 1.5h and the volume of H2O2 2 ml/L, the B/C of the vinylon waste water could be increased from 0.04 to 0.31 and the COD removing efficiency could reach 35%. It was found that microelectrolysis degradation of vinylon wastewater.follow.second.order.model , the.equation Ca=0.0002t+Co-1+0.001 responding the microelectrolysis process.In the anoxic denitrification, removal of organic compound depend on the synergism of hydrolyze acidification, the microorganism metabolism and the denitrifying bacteria. In this experimental, it was found that when resident time for anoxic denitrification was 24 hours, inlet water pH was between from 6 to 8, COD removeing efficiency could reach 20%, and B/C of the waste water was increased from 0.04 to 0.25.After pretreated, two step of contact oxidation MBBR (Moving Bed Biological Reactor) were used to optimize the operation condition in which the cylindrical carrier was been choosen, with packing ratio 60%. Then quick start- pouring way was used to start up and domesticate MBBR. The hydraulic resident time HRT were finally determined to be 12h and the pH value between6~8.Then the dissolved air flotation (DAF) was used to remove the rest SS after MBBR. The pressure of the gas-dissolves storage was controlled at 0.30MPa, gas-dissolve time 25min, and 40mg/L polymerization aluminum chloride added as the coagulant. The COD removing efficiency in this section could approximately reach 50%.Combined process of anoxic denitrification + two step contact oxidations+ dissolved air flotation (A process) and combined process of iron coal + hydrogen peroxide strengthened micro-electrolysis+ two step contact oxidations + dissolved air flotation (B process) were used to treat the vinylon westwater.The COD of the inlet is 600mg/L, 1000mg/L, 1200mg/L and 1500mg/L respectively. COD removing efficiency of A process was between 70%~75%, which could not meet the emission control regulations but for B process, COD removing efficiency was above 90%, meaning that the microelectrolysis could effectively improve the biochemical properties of vinylon wastewater.
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