Method for promoting residual sludge to carry out anaerobic fermentation to produce acid

The invention discloses a method for promoting residual sludge to carry out anaerobic fermentation to produce acid, and belongs to the technical field of solid waste processing and recycling. The provided method aims to solve the problems of low hydrolysis speed and insufficient short-chain aliphatic acid accumulation during the sludge anaerobic digestion process. The sludge is subjected to a nitrite pretreatment to increase the dissolution of organic matters, then the pH value is adjusted to an alkaline area to further promote the organic matter hydrolysis and short-chain aliphatic acid accumulation during the sludge anaerobic fermentation process, and at the same time the activity of microorganisms, which can produce methane, is prohibited, so the yield of short-chain aliphatic acid is increased. The provided method can effectively shorten the retention time of sludge anaerobic fermentation, increase the acid producing efficiency, and achieve the goals of sludge reduction and recycling.