Application of Compound Microbial Preparations in Composting with Lactic Acid Fermentation Residue from Kitchen Waste

In order to utilize the lactic fermentation residue obtained from kitchen waste, composting was carried out with such residue and sawdust. Compound microbial preparations (CMPs) were added into the system to test feasibility to facilitate the composting process. The changes of physicochemical properties and microbiological index were investigated during composting with lactic acid fermentation residue added with sawdust as the conditioner. The results showed that the addition of CMPs resulted in a rapid increase in temperature of the system, and prolonged the maintaining time during high temperature phase. Compared with the system without inoculation (control group), TOC degradation efficiency could be increased by 4.5 %, NH4 -N mass fraction decreased by 71.8 % (30 d), and the NO3 -N mass fraction increased by 35.8 % (30 d) in the inoculated system; furthermore, the release of ammonia could be reduced, thus the function of N maintaining and odor inhibition could be achieved. The amount of microorganisms in the inoculated group was 2~3 orders of magnitude higher than those of the control group. The coliform could not be examined during the final phase of composting, which accorded with the hygienic criterion. The composting of lactic acid fermentation residue from kitchen waste could effectively utilize the fermentative byproduct, and prevent secondary pollution.