A low-carbon-to-nitrogen ratio high-efficiency nitrogen and phosphorus removal process for domestic sewage

Abstract

The invention belongs to the technical field of wastewater treatment, and in particular relates to a high-efficiency nitrogen and phosphorus removal process for domestic sewage with a low carbon-nitrogen ratio. The process mainly comprises the following steps: S1, pretreating the sewage, and respectively introducing the pretreated sewage into an anaerobic MBR reaction tank and an aerobic MBR reaction tank; S2, respectively introducing the sewage treated by the anaerobic MBR reaction tank into an anaerobic ammonia oxidation reaction tank and an aerobic MBR tank; S3, discharging the sludge generated by the anaerobic MBR reaction tank and the aerobic MBR reaction tank to a sludge digestion tank, wherein part of the sludge treated by the sludge digestion tank flows back into the anaerobic MBRtank through a return pipeline, and the other part flows back into the aerobic MBR tank; and S4, discharging the treated sewage after separating by a sedimentation tank. The treatment method can effectively degrade nitrogen and phosphorus in the domestic sewage with the low carbon-nitrogen ratio, and no additional carbon source is needed.

Description

technical field [0001] The invention belongs to the technical field of sewage treatment, and in particular relates to a process for efficient denitrification and dephosphorization of domestic sewage with a low carbon-to-nitrogen ratio. Background technique [0002] Biological denitrification is currently the most economical and effective technology in sewage denitrification treatment, including two processes of nitrification and denitrification. The traditional nitrification and denitrification can only realize the complete denitrification and denitrification process under the condition of sufficient carbon source and large aeration; in the pre-denitrification, incomplete denitrification occurs when the influent COD / TKN<15, and the water quality in my country It is characterized by a low carbon-to-nitrogen ratio, which is about 3.3 to 8.5. Therefore, it is necessary to add carbon sources, which not only increases the treatment cost, but also emits carbon dioxide gas and po...

AI Technical Summary

Problems solved by technology

However, MBR reactors are prone to membrane fouling, especially sludge bulking, resulting in a decrease in the performance of the membrane module and a decrease in the water treatment effect.