Method for producing volatile fatty acid by normal-temperature low-oxygen digestion of yeast reinforced excess activated sludge

Abstract

The invention provides a method for producing volatile fatty acid by normal-temperature low-oxygen digestion of yeast reinforced excess activated sludge and belongs to the technical field of treatmentof municipal sewage and sludge. Aiming at the problem of insufficient accumulation of volatile fatty acids in an excess sludge digestion process, a yeast inoculation method is adopted during initialsludge digestion, macromolecular organic substances in sludge are degraded by rich enzyme systems of the yeast, and production of volatile fatty acids is promoted. Cheap and easily available yeast isadopted in the method, the yield of volatile fatty acids is increased substantially, and when the concentration of the yeast is 10 g / L, the highest concentration of volatile fatty acids is 10-12 timesthe concentration of volatile fatty acids without the yeast. A digestion product rich in volatile fatty acids is used as an organic carbon source of function microbes for removing nitrogen and phosphorus from the sewage, sludge reduction and recycling are realized, the problem of insufficient carbon source of a municipal sewage treatment plant in a biological nitrogen and phosphorus removal process is solved, cost for feeding an external carbon source is saved, and the nitrogen and phosphorus removal effect of the sewage treatment plant is improved.

Description

technical field [0001] The invention belongs to the technical field of urban sewage sludge treatment, and relates to a method for using angel yeast to strengthen normal-temperature micro-aerobic digestion of excess activated sludge to produce volatile fatty acids. Background technique [0002] Water eutrophication has become the most prominent global water environment problem. A large number of studies have shown that the excessive discharge of sewage rich in nitrogen and phosphorus is the main cause of surface water eutrophication. Biological nitrogen and phosphorus removal technology has been widely used in sewage treatment plants in major cities due to its cost-effective features. At present, urban sewage plants are facing two major problems in the process of operation: one is insufficient carbon source, which has become the bottleneck of low C / N ratio sewage denitrification and phosphorus removal; Disposal. Therefore, the development of internal carbon sources and the ...

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Problems solved by technology

The hydrolysis process in the three stages is slow and is the rate-limiting step of anaerobic digestion, so anaerobic digestion generally requires a longer residence time and a larger digester

However, these processes can only simply improve sludge stability and dehydration performance or increase methane production, and cannot make sludge digestion stay in the hydrolysis and acidification stage, so that the organic matter in the sludge is not completely decomposed or converted into methane

When using sludge micro-aerobic digestion technology to treat sludge, although there is a small amount of aeration, it is not in a real aerobic state, but in an anoxic state

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