The new process for short-cut nitrification A/SBR treatment of ammonia-containing wastewater developed by the Xuzhou Institute of Water Treatment was recently assessed by the China Environmental Protection Industry Association as a national key environmental protection practical technology promotion project in 2008. The process is very suitable for the treatment of fertilizer waste water with a low C/N (carbon/nitrogen) ratio and is now widely used in the domestic terminal sewage treatment project of small and medium-sized nitrogen fertilizer production enterprises.
According to Huang Huayao, director of the Xuzhou Institute of Water Treatment, the short-cut nitrification is relative to the traditional nitrification process. Because of its short reaction time, it is called "short range." Short-cut nitrification process can stay in the nitrous acid phase to directly denitrify to produce nitrogen gas, and there is less nitrite reaction stage. Because the properties of nitrite bacteria are similar to those of nitrite bacteria, it is very difficult to react with nitrite bacteria without nitrate bacteria reaction. This is the reason why the short-run nitration process has long been unsuccessful in the treatment of ammonia wastewater.
After several years of arduous research, Xuzhou Institute of Water Treatment finally grasped the technical key of short-cut nitrification process and achieved a breakthrough in industrial applications. The short-cut nitrification process saves 25% of the compressed air and the corresponding power consumption is greatly reduced compared with the traditional process; it saves 40% of the organic carbon source required for denitrification, which saves a lot of treatment chemicals for synthetic ammonia drainage with a low C/N ratio. Cost; Two-step reaction is omitted, the nitrification reaction time is shortened, the aerobic tank capacity is smaller, and the investment is reduced; the direct denitrification rate of nitrogen dioxide is 63% higher than that of nitrogen trioxide, and the denitrification time can be shortened. Reduce infrastructure investment by 20%-25%; reduce efflux sludge by 4-0%-50%, reduce sludge treatment costs by 50%; reduce nitrification reaction by adding alkali, and increase denitrification efficiency by more than 95%, correspondingly The remaining base is produced for the nitration reaction, saving 30% of the amount of alkali used for neutralization. Taken together, the new short-cut nitrification A/SBR treatment process saves energy, saves water, saves investment, and saves processing costs. It costs 20% to 30% more than the provincial capital investment in the traditional process, and the provincial wastewater treatment costs 20% to 30%. .
Two years of industrial trials at the chemical fertilizer plant have demonstrated that the new process can produce a COD (Chemical Oxygen Demand) concentration of 400 (0000 mg/L, ammonia nitrogen 1000) in the case of the treatment of circulating water for a gasification process with a treatment volume of 100 m3/day. -1,600 mg/l, carbon and nitrogen 5-10 mg/l influent, becomes COD concentration 100-150 mg/l, ammonia nitrogen 10 to 50 mg/l, carbon nitrogen 1 mg/l effluent, in line with the national level Emission standards: The nitrite ion concentration in treated water accounts for 80%-90%, which is in line with the technical characteristics of short-cut nitration process requirements with nitrite ion greater than 50%. In September 2006, Xuzhou Institute of Water Treatment successfully developed Shandong Deqilong Chemical Co., Ltd. The Group has designed a large-scale terminal chemical fertilizer plant with a treatment capacity of 15,000 cubic meters per day and an investment of 20 million yuan. It has been put into operation in May 2007 and has been operating normally since.