Brief introduction to the technology of moving bed biofilm enhanced simultaneous nitrification and denitrification technology. By adding suspended carriers to the aerobic biochemical zone of the sewage treatment plant, pool-type transformation and pool capacity distribution of the biochemical zone, improves the sewage treatment process and forms the MBBR technology process coupling with the active sludge system, thus transforming the conventional active sludge process into the sludge-biofilm composite system The technology improves the microbial population structure of the system, and achieves the simultaneous nitrification and denitrification in the aerobic zone and the in-situ strengthening of the organic matter removal in the sewage by utilizing the characteristics of the stratified distribution of the suspended carrier biofilm, improving the total nitrogen removal effect and the raw water carbon utilization. the effluent standard can reach the Class I water quality standard of Grade A or higher. Based on the basic theories of hydraulics and microbiology, the technology can enhance the removal of total nitrogen by simultaneous nitrification and denitrification by adding suspension carrier in the aerobic area, and reduce the aerobic area for the subsequent anoxic denitrification area to ensure the removal effect of total nitrogen The technology studied the influencing factors of simultaneous nitrification and denitrification in aerobic suspension carrier zone; developed a control method for simultaneous nitrification and denitrification in aerobic zone, and finally forms the water treatment process of in-situ enhanced denitrification in the biochemical system under the engineering conditions of low water quality concentration, low carbon nitrogen ratio sewage and short residence time. The technology allows the denitrifying bacteria to make full use of the raw water carbon source through pool type modification and pool capacity distribution. Without adding carbon source, the effluent TN of biochemical tank is discharged stably to meet the standard, and the cost of adding carbon source is reduced e. The technology has stable operation, small floor space, strong impact resistance and stable operation. It can reasonably adjust the quantity and function of the operating biological pool according to the actual water intake, and ensure the safe and continuous operation of the water plant. Through the combination with existing phosphorus and nitrogen removal technologies and hydraulic optimization design, a series of process and system solutions suitable for different types of urban sewage quality characteristics and actual needs have been formed. The actual engineering application scale reaches 8 million m³/d.

Experts commented that the technology converts the original activated sludge process into the sludge-biofilm composite system by adding suspended carriers to the aerobic biochemical zone of the sewage treatment plant, improving the microbial population structure of the system. And utilizing the characteristics of the stratified distribution of the suspension carrier biofilm, the simultaneous nitrification and denitrification in the aerobic zone is realized, and the total nitrogen removal effect and the utilization rate of the raw water carbon source are improved. The technology combines with the existing phosphorus and nitrogen removal technology and hydraulic optimization design to form a series of process and system solutions suitable for different types of urban sewage water quality characteristics and actual needs, the actual engineering application scale reaches 8 million m³ / d. The engineering application in different regions of China shows that the technology runs stably and the effluent quality meets the requirements of Class A and above of the “Emission Standard for Pollutants in Urban Sewage Treatment Plants” GB18918-2002, and the users have a good response.