Device and method for utilizing carbon source in sludge to treat urban sewage through in-depth nitrogen and phosphorus removal by SBR (sequencing batch reactor)

Abstract

The invention discloses a device and method for utilizing a carbon source in sludge to treat urban sewage through in-depth nitrogen and phosphorus removal by an SBR (sequencing batch reactor). The device comprises a sludge fermentation tank, a fermentation liquor separation tank, a fermentation liquor nitrogen and phosphorus removal tank, a carbon source storage box, an urban sewage tank and an anaerobic/aerobiotic/anoxic SBR, wherein the sludge fermentation tank is airtight, and a stirrer is arranged on the sludge fermentation tank; the anaerobic/aerobiotic/anoxic SBR is an open tank, and a stirrer and an aerating apparatus are arranged on the anaerobic/aerobiotic/anoxic SBR. The method comprises the following steps: urban sewage enters the SBR; in one cycle, firstly, under the anaerobic condition, phosphorus-accumulating bacteria utilize the carbon source in raw water to release phosphorus in an anaerobic manner; then, under the aerobiotic condition, nitrobacteria has nitration reaction and phosphorus-accumulating bacteria absorb phosphorus; finally, under the anoxic condition, denitrifying bacteria utilize a fermentation liquor containing short-chain fatty acid and generated through anaerobic fermentation of sludge to have denitrification; nitrogen and phosphorus in urban sewage are removed through repeating the above steps. According to the invention, an external carbon source is not required, and nitrogen and phosphorus removal is performed by utilizing the carbon sources in the urban sewage and the fermentation liquor, so that the cost is reduced and the amount of sludge is also reduced.

Description

technical field [0001] The invention relates to a device and a method for deep denitrification and dephosphorization of urban domestic sewage treated by SBR using a carbon source in sludge, and belongs to the technical field of sludge sewage treatment. Background technique [0002] In the traditional anoxic\anaerobic\aerobic SBR, the denitrifying bacteria preferentially use the carbon source for denitrification. When anaerobic, the phosphorus-accumulating bacteria often reduce the phosphorus release effect due to the lack of carbon sources. Therefore, the aerobic phosphorus-accumulating bacteria Phosphorus uptake is limited, and in addition, nitrifying bacteria carry out nitrification reaction during aerobic conditions, that is, NH 4 + -N is oxidized to NO 2 - -N, NO 3 - -N, although the ammonia nitrogen in the effluent has been reduced, the TN is still very high, and it is difficult to meet the first-level A standard. In order to deeply remove nitrogen and phosphorus, ...

AI Technical Summary

Problems solved by technology

[0002] In the traditional anoxic\anaerobic\aerobic SBR, the denitrifying bacteria preferentially use the carbon source for denitrification. When anaerobic, the phosphorus-accumulating bacteria often reduce the phosphorus release effect due to the lack of carbon sources. Therefore, the aerobic phosphorus-accumulating bacteria Phosphorus uptake is limited, and in addition, nitrifying bacteria carry out nitrification reaction during aerobic conditions, that is, NH 4 + -N is oxidized to NO 2 - -N, NO 3 - -N, although the ammonia nitrogen in the effluent has been reduced, the TN is still very high, and it is difficult to reach the first-level A standard. In order to deeply remove nitrogen and phosphorus, it is necessary to add an external carbon source, which undoubtedly increases the operating cost.

Images