The invention relates to a method for enhancing dry-process
fermentation stability of
sludge by adding kitchen waste, belonging to the field of
solid waste recycling. The invention can solves the problems of low acidifying degree of
hydrolysis, insufficient substrates for producing
methane, overhigh pH value,
ammonium salt accumulation, inhibition of gas generation and the like caused by high
viscosity of
dewatered sludge, high TS concentration, low C / N value and the like. The method comprises the following steps: pulverizing kitchen waste, mixing the kitchen waste and
dewatered sludge in the weight ratio of 1:10-15, putting the mixture in a
fermentation tank to ferment, and sufficiently stirring, wherein in the
fermentation process, the temperature of the materials is kept at 35+ / -1 DEG C, and the oxidation-
reduction potential is smaller than or equal to -300mV; when the pH value rises to 7.5 and the
methane content rises to higher than 35%, adding the kitchen waste into the fermentation tank again in batches, wherein the addition amount of the kitchen waste each time accounts for 5-10 wt% of the
dewatered sludge, the pH value of the
mixed materials is preferably greater than or equal to 6.6, and the preferable addition time is when the pH value of the materials rises to higher than 7.5; and when the
methane content is lower than 35% and the gas
generation rate obviously decreases, finishing the fermentation. The invention can be used for municipal
sludge recycling and
energy recovery. Compared with wet fermentation, the invention can save equipment investment and soil occupation.