Study on NO2--N accumulationof soybean wastewater treatment by SBR process

The bean products wastewater treatment process has been studied by SBR. Theexperimentstudied effective of reaction timeunder low dissolved oxygen on SBR system. The experimental result indicated that under the condition of influent COD is 330~460mg/L, the reactor has a good degeneration ability of COD, NH4 + -N、PO3 - -P、 NO 2 - -N、NO4 3- -P. And NO2 - -N accumulation reached a maximum after aeration 3 hours, Aeration and time were saved effectively while stop the aeration at this time, thus power and costs were saved. Soy products food are made from soybean bean, broad bean, mung bean as the main raw material. Most soy products are made from soy bean curd, which is made from the fight of soy bean curd and its recycle products. Organic compounds (protein, starch, sugar, amino acid) in the production process of bean products are very high and easy to corrupt, not only containing harmful substances and easy degradation, but also it weak acid wastewater (1) . Production of wastewater directly efflux not only cause very serious environmental pollution, but also impact on people's living environment. Bean products are rich in nutrition and high nutritional value. Contains a large number of protein and amino acids. It also has a good health care function, improve human immunity, prevention of osteoporosis and so on. Because of bean products has many tastes and diverse practices that more and more people regard it as daily snacks and cooking food. Therefore, the more people demandof bean products, The worse production of bean wastewater, which makes it urgent to strengthen and improve the processing technology of beanwastewater. (2-6) . At present, the treatment of bean wastewater of domestic and international mainly uses the biological treatment method has UASB, A2O, contact oxidation method, biological turntable and other processes (7-9) . But most of them areExpensive equipment, installation of high technical requirements, the management is complex, covers a vast area.Using SBR has the process simplely, the stro ng capacity sewage treatment,flexible operation, easy automation, etc. On the contrary, it cover an area of area small. It is a more economical and practical wastewater treatment process in treatment of bean products wastewater (10) .