| Based on the systemic study to literatures, the microcosmic mechanism of microorganisms decaying organics during aerobic composting of municipal organic solid waste was analyzed and discussed according to the biochemical reaction mechanism, and the biology characteristics of microorganisms and decaying bionomics, the energetic change in decaying process and composting kinetics during aerobic composting were concluded and consolidated. Therefore the problems presently existed in the composting technology were summarized.The aerobic vessel composting experiments were carried through in laboratory. Main factors of influencing organic solid waste biodegradation, which included composting material kinds, temperature, moisture content, particle size and C/N ratio in aerobic composting, were investigated by running a set of bench-scale, laboratory experiments. The experimental results showed the optimum process conditions were temperature of 40-50 ℃, moisture content of 50%, particle size of 30mm and C/N ratio of 30:1. Moreover, the experimental results also showed examined former factors should be carefully controlled in proper range for ensuring composting reaction. In addition, the factors were compared by orthogonal experimental design. The results showed that moisture content was the most important effect factor to TOC biodegradation, C/N ratio was next, temperature and particle size was the least.The aerobic composting of water-rich agricultural plants waste and other type municipal plant waste were studied respectively too. The experimental results showed degradation rate of organic matter in water-rich agricultural plants waste was 69%, which was the highest in these composting plants. The degradation rate of organic matters in other plants waste was raised largely when they were mixed into compost with water-rich agricultural plants waste and the highest degradation rate got to 39.1% when ratio of the mixed material was 2:1. The change of degradation rate was found to have relation with composition of the water-rich agricultural plants which was 80% water content and other easy degraded organic matters such as protein, fatty, fiber and other carbohydrate whose C/N ratio was 10:1-3 5:1 In addition, mature time of the composting can be shorten largely when the water-rich agricultural plants waste were added into the composting material, and the shortest mature time was 20 days.The nitrogen loss and its restraining technology were studied in aerobic composting also.The three kinds of sorbents of 0.18%(wt/%, unless stated otherwise) KH2PO4, 0.06%KH2PO4+15%Sawdust mixture and 30%Sawdust were added separately into composting to investigate their adsorption effect on ammonia. The experiment results exhibited that all the sorbents could restrain ammonia volatilizing. But sorption of 0.18%KH2PO4 sorbnet was best of all, one of 0.06%KH2PO4+15%Sawdust mixture sorbent was secondly, one of 30%Sawdust sorbent was thirdly. The total nitrogen loss ratios were separately reduced 25%, 23% and 17% after adding the three kinds of sorbents into composting. However, 0.18%KH2PO4 was excessive on demand quantity of composting and would produce negative influence on composting property, such as: pH value being lessened, microorganism activity being reduced, and finally resulting in the reduction of biodegradation ratio of organic matter also. Comparing with it, there were not these problems as 0.06% KH2PO4+15%Sawdust mixture being sorbent. The mixture sorbent not only produced finer adsorption effect on ammonia, but also made biodegradation ratio of organic matter to be promoted 7%.In addition, the character and kinetic for the growth of microorganism were investigated in aerobic composting process. It was considered that the growth of microorganism was affected largely by temperature. It showed wave change of growth of microorganism alone with temperature change. Meanwhile, a kinetic model of microorganism growth in the aerobic composting was established based on Logistic model and Malthus model. The model is scientific according to its...
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