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Acrylonitrile is an important chemical material, which is applied widely in the field of chemical products. In the production process of acrylonitrile, wastewater which they produce has complex ingredient. There are few reports on specific pollutants of acrylonitrile wastewater, which can present an impenetrable barrier to studying treatment methods of acrylonitrile wastewater. In this work, we analyzed general monitoring index and specific pollutants ingredient, studied biotreatment effect of acrylonitrile wastewater using A/O/O process, analyzed transformation of specific pollutants in A/O/O process, and discussed impact factors inhibiting NH4+-N nitration and quantitative relationship between nitration and consumption of alkalinity. The results of this work are a good reference for biotreatment of acrylonitrile wastewater.The specific pollutants of acrylonitrile wastewater were analyzed by GC-MS and HPLC, the results showed pollutant type included pyridine, amide, organic acid, phenol, nitrile, pyrimidine, pyrazole and heterocyclic substance; specific pollutants with high contents were 3-cyanopyridine, nicotinamide, nicotinic acid, acrylonitrile, acrylic acid, A and B. In the A/O/O process, in the anoxic pond the removing rate of 3-cyanopyridine, acrylonitrile and B reached 91.2%,100% and 51.3%, respectively; in the aerobic pond one the removing rate of 3-cyanopyridine, nicotinamide, nicotinic acid, acrylonitrile, acrylic acid and B all reached 100%, only A was accumulated in effluent of A/O; in the aerobic pond two A was removed.When the influent COD is 962-2037mg/L, pH is 6.90～9.80, NH4+-N is 46.8～151mg/L, N03--N is 213～425mg/L, effluent of A/O COD removal rate is 78%, pH is about 8.2, NH4+-N is 215～420mg/L, NO3--N removal rate is above 96%; effluent of aerobic pond two COD removal rate is 82%, pH is about 6.0, NH4+-N is 100mg/L, NO3--N is 200mg/L; in the aerobic pond one impact factors inhibiting NH4+-N nitration is A accumulated in effluent of aerobic pond one; in the aerobic pond two nitration recovered after A was removed, but because of insufficient alkalinity NH4+-N was not transformed to N03--N completely.
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