Method for producing volatile short-chain organic acid by promoting anaerobic fermentation of solid organic waste

The invention relates to a method for producing a volatile short-chain organic acid by promoting the anaerobic fermentation of solid organic wastes, and belongs to the field of reutilization of the solid organic wastes. The method comprises the following steps of: pretreating by taking excess sludge as a mode substrate and adopting NaOH, and then centrifugalizing to take supernatant as the influent water of a reactor; inoculating acid-producing seed sludge for anaerobic acid production reaction; and adding a small amount of hydrated metal compounds to promote the growth and activity of an acid-producing bacterium group at an initial fermentation stage, wherein the adding mount is between 1-300 mg/L or 1-3000 mg/L, and the maximum output of the volatile short-chain organic acid can achieve 0.32 gram of volatile short-chain organic acid/gram of organic substances and is enhanced by 12%-58.0% compared with the output of a contrast example acid which is not added. The method disclosed by the invention promotes the organic substances contained in the wastes to efficiently biologically transform into products with high added-value, promotes the minimization of the organic wastes and solves the problem of environment pollution caused by the organic wastes and has the characteristics of low cost, high transformation rate, short fermentation period and the like; and the adding amount of the hydrated metal compounds is extremely small, and equipment needed in a fermentation process is simple.