| Epoxy propane saponification wastewater in Mei zhouwan chlor-alkali Industry Co., Ltd. with high-salinity, high COD and high pH was proposed to treat by using Activated sludge process and biological contact oxidation process.The parameters such as hydraulic retention time(HRT), dissolved oxygen (DO), salt concentration shock load are considered in the unit of activated sludge process and biological contact oxidation process. Experimental result showed that the removal efficiency of COD reached 85.10% when HRT is 18h. When the influent pH is 11,the effluent pH can keep between 78and influent pH has no distinguished impact on removal efficiency of COD. The optimal DO in activated sludge process and contact oxidation process are respectively 4 mg/L and 6mg/L. The removal efficiency of COD decreased under the shock of influent salinity, but the unit perform well as salinity changed in the scope of ±50%.The effect of calcium chloride on activated sludge was researched in the Activated sludge process. The result showed when calcium chloride concentration raised from 0mg/L to 40000 mg/L, removal efficiency of COD descended from 92.9% to 56%,the OUR(oxygen uptake rate) and MLVSS/MLSS decreased too, while inorganic element and setting property of activated sludge increased. The species of microorganism in zoogloea decreased with the increasing of the salt and zoogloea becamed more compact. Rotifer, wireworm exist in zoogloea at salt concentrations of 10000 mg/L while protozoa and metazoan disappeared when calcium chloride concentration is 30000 mg/L.The kinetic model of wastewater biodegradation in the Biological contact oxidation process was researched and the equations is established :207 (1/S) +0.01783. It accorded with Monod equations when reaction time is24h.The maximum growth rate coefficient Umax =56.02mg/(L·h)and Monod coefficient KS=67.83mg/(L·h).
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