Study On Dispersed Rural Wastewater Treatment Equipment And Its Application

The large amount of rural sewage in China is discharged casually without treatment,which causes pollution and destruction of rural water resources and water environment,and poses a great threat to the health of rural people.China's decentralized wastewater treatment process,however,is still in its infancy,and various processes have certain limitations.A new type of distributed rural sewage integrated equipment is designed for the rural sewage in China.Meanwhile,the simulated sewage is treated with it,and its optimum working conditions are studied.The new decentralized rural wastewater integration equipment,aimed at the feature of China's rural sewage,integrates AO and MBR technologies for the purpose of removing organics and removing nitrogen and phosphorus in the traditional principle of nitrogen and phosphorus removal in the AO.Based on this,the enhanced biological adsorption selective zone is added to enhance the removal of nitrogen and phosphorus.The new decentralized rural sewage integration equipment mainly includes a regulating tank,a reinforced biological adsorption selection zone,an anoxic tank,an aerobic tank,and an MBR tank.First,each reaction zone is calculated and designed based on the characteristics of each sewage,and drawing work is completed;the auxiliary devices are selected.Finally,the prepared reaction zones and accessories are rationally arranged and installed;after the initial commissioning,the new integrated equipment design and production work is completed.Using the new decentralized rural wastewater integrated process equipment to treat the simulated wastewater,the optimal operating conditions of the equipment are explored.The experiments include startup,mixture reflux ratio,influent flow,influent C/N,influent COD,and ammonia nitrogen concentration.During the start-up process,it is found that the removal rate of pollutants increased significantly.Finally,a higher removal rate is achieved.The removal rates of COD and ammonia nitrogen are more than 90%,and the removal rates of total nitrogen and total phosphorus reach more than 65%.In the study of the optimal working conditions,the ratio of COD/NH4+-N in the mixed liquid reflux ratio was 600%,the inflow flow was 20L/h,the influent C/N was 5,the influent COD and ammonia nitrogen concentrations were 150 and The best removal efficiency is 30mg/L.Under these four conditions,the removal efficiency of COD andammonia nitrogen is up to 95%,and the removal efficiency of total nitrogen and total phosphorus is up to 81.9% and 81.4%.COD,Ammonia nitrogen and total nitrogen effluent concentrations are in line with the first-grade standard of the “Discharge Standards for Pollutants in Urban Wastewater Treatment Plants”(GB18918-2002),and the total phosphorus concentration fluctuates above and below the standard.It can be seen that the new decentralized rural wastewater integration equipment has a high removal rate of organic matter and a strong nitrogen and phosphorus removal function for the treatment of simulated sewage,and it has good impact resistance to changes in water quality and water volume.