Study On Treatment Of The High Concentration Organic Wastewater In Food And Fermentation Industry

There is a large amount of water needed and a huge amount of waste water discharged in food fermentation industry. If the wastewater discharged directly without professional treatment, it would pollute the surrounding ecological environment, which is difficult to restore. With the environmental requirements becoming increasingly stringent in our country, enterprises are required to take measures to reduce water consumption as much as possible, and to reduce the discharge of waste water generated, which avoides environmental problems caused by excess emissions of wastewater.On the basis of abundant literatures, this paper takes the wastewater produced by a food fermentation enterprise as the research object, using a combined process of UASB+Bio-Contact Oxidation+BIORFOR to deal with and piurfy it. Through the study of the process of commissioning and operation Conclusions are drawn as follows:(1) it would take about three months for the debugging of UASB. During the commissioning, the reactor temperature,pH,VFA and VFA/ALK of UASB should be controlled at35±2℃,6.8～7.2,300mg acetic acid/L and0.4or less, until the granular sludge was successful cultured.(2) With respect to the UASB, it is relatively simple for the debugging of biological contact oxidation pool and BIOFOR. As the the biodegradability of wastewater was good and the temperature of the UASB effluent was high, which contributed a favorable reaction conditions for the biofilm of aerobic structures, so the biofilm of biological contact oxidation pool and BIOFOR filter started fast.(3) During the stable operation, the UASB effluent COD concentration stabilized between452to874mg/L, COD removal rate maintained within the high range of79%to92%higher, the average rate was85.5%,The inffiuent quality, effluent quality and HRT were in accordance with Ce=Coe-0.0352t; biological contact oxidation pond effluent COD concentration was kept at the range of113to246mg/L, the average effluent concentration was180mg/L, and the COD removal rate was in the high range between65to80%, the average removal rate was73%; BIOFOR filter effluent COD concentration was maintained at44to87mg/L, the average was66mg/L, meeting the emission standards,COD removal efficiency was in the range of59%to72%, with an average of66.5%.(4) During the stable operation of the whole system, the total removal of COD was high up to99%, the total removal of chroma was90%, the cumulative removal rate of SS was95%, the effluent quality was stable and reliable, satisfying the emission standards.(5) In the daily operation, the structures, equipment, and safety management must be strengthened. Timely measures should be taken to adjust to ensure the normal operation of the sewage treatment station in case of irregularities.(6) The total investment was2,447,130yuan, including civil works for136.2million. Daily running costs were1580.65yuan, equivalent to2.63yuan/tons of water. The operating cost was low and the economic feasibility was high.