The technical invention of this project is aimed at the actual needs of decentralized sewage treatment in rural towns and villages in China. It has completed multiple inventions and innovations in pre-treatment, biological treatment, advanced treatment, sludge treatment, operation and maintenance, etc., providing technical support for reducing the construction and operation costs of rural sewage treatment, achieving stable and compliant discharge, and operational maintenance. It effectively solves problems such as non-compliant technical processes and difficulties in operation management that exist in the decentralized sewage treatment process in China's rural towns and villages, and is of great significance for improving the water environment in rural areas. The main technical invention points at different stages of decentralized sewage treatment in rural towns and villages are as follows: (1) Pre-treatment: In view of the diverse types and sizes of impurities in rural sewage, an automatic small-scale slag removal device suitable for different sized particles has been invented. It can pre-treat the rural sewage, effectively remove impurities while ensuring stable effluent and uniform distribution of water. Applicable to small-scale integrated sewage treatment devices in villages and towns, which can be widely promoted and applied on a large scale. (2) Biological Treatment: In response to the high dispersion of wastewater in China's villages and towns, complex composition, significant changes in water quality and quantity, and higher pollutant indicators, as well as the diverse water quality requirements for effluent from different regions, this project has independently invented biological treatment processes such as A2O-SBR and A2O-MBR for village and town wastewater, enzyme-catalyzed suspended fillers, composite modular integrated reactors, etc. The treatment process is simple and flexible, with low equipment investment and energy consumption. It can achieve efficient treatment of wastewater from different regions, with effluent quality meeting the 'Pollutant Discharge Standards for Urban Sewage Treatment Plants' (GB18918-2002) Class B or Class A standards, and even the 'Surface Water Environmental Quality Standards' (GB3838-2002) for Class IV water bodies. Suitable for large-scale application in decentralized sewage biological treatment processes in villages and towns. (3) Deep treatment: In response to the frequent non-compliance of phosphorus concentration in effluent from village and town sewage treatment systems that prioritize denitrification, as well as the problems of normal operation due to lack of effective regular maintenance caused by management level and operational funds limitations, this project has invented an automatic backwash siphon filter phosphorus removal device for deep treatment of village and town sewage. This device can automatically clean the phosphorus removal material during the process of sewage filtration and phosphorus removal, achieving deep treatment of village and town sewage while significantly reducing operational costs. (4) Sludge treatment and disposal: Based on the concept of resource utilization, addressing issues such as different sludge properties often resulting from varying water quality during village and town sewage treatment, which increases the difficulty of sludge treatment and disposal, this project has separately invented technologies for producing emulsion breaking bacteria, short-chain fatty acids, and microbial fertilizers from sludge. It can efficiently treat and dispose of residual sludge with different physicochemical properties generated during the biological treatment and advanced treatment processes of village and town sewage, achieving sludge reduction, harmlessness, and resource utilization. It is suitable for large-scale application in the treatment and disposal process of village and town sludge. (5) Sewage Treatment System Control: This project has invented a real-time monitoring system for sewage treatment that integrates data collection, transmission, processing, storage, and other units. It provides a complete solution for the real-time monitoring of decentralized sewage treatment in villages and towns, allowing for objective, accurate, and timely understanding of dynamic changes in the operation of treatment facilities. It effectively addresses issues such as limited technical management experience and difficulty in operation and maintenance management in the decentralized sewage treatment process of villages and towns in China. The project has obtained 21 authorized patents, including 8 invention patents and 13 utility model patents, and has published 11 papers. The research results have been successfully applied in regions such as Shanghai and Anhui. Each year, about 30 million cubic meters of rural sewage are treated, with annual reductions in COD, total nitrogen, and total phosphorus of approximately 10,500, 960, and 108 tons, respectively. In the past three years, new added value has nearly reached 30 million yuan, resulting in significant environmental, economic, and social benefits.