Copper sulfate combined with alkaline ph to promote the method of anaerobic fermentation of excess sludge to produce short-chain fatty acids

Abstract

The invention discloses a method for promoting anaerobic fermentation of excess sludge by combining copper sulfate and alkaline pH to produce short-chain fatty acid and belongs to the technical field of environmental protection. According to the method, the excess sludge in a municipal wastewater treatment plant is used as the raw material; firstly, the copper sulfate is added to make the walls of microorganisms in the excess sludge break; secondly, the excess sludge is washed to remove copper ions; lastly, the pH value of the excess sludge is adjusted to be alkaline for anaerobic fermentation. After the excess sludge is pretreated through the copper sulfate, the hydrolysis rate is increased in the anaerobic fermentation process, and the yield of the short-chain fatty acid is increased; besides, the alkaline pH further promotes wall breakage of the microorganisms in the excess sludge and effectively suppresses the activity of methane bacteria produced in the anaerobic fermentation process, so that organic matter in the excess sludge is converted into the short-chain fatty acid to the maximum extent, and meanwhile the short-chain fatty acid is prevented from being converted into methane and is accumulated. The copper sulfate adopted in the method can effectively promote anaerobic fermentation of the excess sludge to produce the short-chain fatty acid at a small dosage, and meanwhile the effect of sludge reduction is achieved.

Description

technical field [0001] The invention belongs to the technical field of environmental protection, and relates to a method for promoting the anaerobic fermentation of excess sludge to produce short-chain fatty acids by using copper sulfate combined with alkaline pH. Background technique [0002] At present, most urban sewage treatment plants use the activated sludge method to treat sewage. On the one hand, the serious shortage of carbon sources in urban domestic sewage has become one of the main limiting factors for the deep denitrification and phosphorus removal of sewage treatment plants; A large amount of excess sludge will be produced, and the treatment and disposal costs are relatively high. The remaining sludge contains a large amount of organic matter such as protein and polysaccharide, which can be converted into short-chain fatty acids through anaerobic fermentation technology, and used as a high-quality carbon source for microbial nitrogen and phosphorus removal. ...

AI Technical Summary

Problems solved by technology

On the one hand, the serious shortage of carbon sources in urban domestic sewage has become one of the main limiting factors for the deep denitrification and phosphorus removal of sewage treatment plants; A large amount of excess sludge will be generated, and the treatment and disposal costs are relatively high