Research On Key Technology Of Negative Pressure Integrated Sewage Treatment Equipment

The high content of suspended solids and organic matter in domestic sewage pose a serious threat to the sustainable development of the environment,land,and air quality.As rural economies develop,the quality of life for farmers improves,leading to a natural increase in domestic water usage and the generation of a large amount of domestic sewage.Existing domestic sewage treatment methods require the construction of various treatment ponds,which have a large area,high operating and maintenance costs,long construction periods,and require specialized technical personnel for operation.This limits their use in rural areas,where the costs of large-scale sewage treatment plants or outsourcing services are too high.Therefore,it is urgent to explore a negative pressure sewage treatment process and equipment,and design an integrated machine for negative pressure domestic sewage treatment in rural areas.Through an analysis of the current research status at home and abroad,it was found that most domestic sewage treatment systems occupy a large area;Although they make every effort to ensure that the sewage treatment meets the specified discharge standards,they have ignored the air pollution problem caused by odor overflow during the treatment process.This study focuses on domestic sewage from Caomiao Township in Gushixian,with COD(chemical oxygen demand)as the primary detection index.Through theoretical and practical research,an A/O process-MBR process-Negative pressure process was determined as the optimal method for treating domestic sewage.The negative pressure process was also used to treat odors generated during equipment operation.The best negative pressure value for treating Caomiao Township’s domestic sewage was determined based on experimental results and data processing.The water quality of domestic sewage treated by the combined process met the first-grade A standard of pollutant discharge for urban sewage treatment plants(GB18918-2002),with COD values ranging from 23.77 mg/L to 47.55 mg/L under seven different negative pressure values.This method can provide design references for other rural sewage treatment systems.Key components for negative pressure integrated sewage treatment equipment were designed and 3D models were established according to the proposed domestic sewage treatment process.The finite element analysis of the stress and strain conditions of the entire machine and the top cover subjected to the pressure of the negative pressure carbon box was conducted to verify the feasibility of the design scheme.Based on the design plan,a prototype was designed and produced to test the main performance of the negative pressure sewage treatment integrated machine,including the treatment effect of the A/O treatment pool,the filtration effect of the MBR pool,the odor treatment effect and negative pressure effect of the negative pressure carbon box,and the impact of negative pressure on the overall water treatment efficiency of the integrated machine.The experimental results showed that under seven different negative pressure values,the COD removal rates for Caomiao Township’s domestic sewage ranged from 46.30 % to 90.97 %,with the best water treatment effect achieved at a negative pressure value of 400 pa,meeting the first-grade A standard of pollutant discharge for urban sewage treatment plants(GB18918-2002).The negative pressure sewage treatment process and equipment developed in this study provide a feasible and efficient solution for rural domestic sewage treatment.