BIOLOGICAL ENHANCEMENT BASED ON CAST PROCESS AND DENITRIFICATION PERFORMANCE OF SOLID CARBON SOURCE FOR LOW C/N DOMESTIC SEWAGE

In winter, low sludge activity, low microbial abundance and low C/N directly affect the quality of wastewater and the removal of total nitrogen in wastewater treatment plants. In this paper, the CAST process for treating low C/N domestic sewage is selected as the experimental reactor, and the method of a combining solid carbon source with biological reinforcement is used to raise the discharge of effluent up to the standard The target bacteria were immobilized with artificial filler, and different bacterial components were placed in different positions of CAST reactor. The ammonia nitrogen, total nitrogen and COD in the effluent of the system were measured, and the changes of microbial community structure in the treatment process were analyzed by PCR-DGGE technology, so as to determine the effect of solid carbon source and biological reinforcement on the denitrification performance of CAST process.