| This paper had three parts. First was conducted to analyze the compost ratio and the acceptance potential of municipal solid waste (MSW) by investigating and evaluating status of generation, components, treatment and utilization of MSW in Beijing; Second was studied to find out the key factor of composting and some technology measures about the further process of compost in NanGong composting plant and to analyze market distribution, quality of MSW compost and to give practicable advice according to the survey; Third was performed to study on the effect of the MSW compost and organic-inorganic compound fertilizer on plant growth to solve the series of problems such as the low quality and low content of nutrient and organic matter and to put forward technology measures of enhancing MSW compost effect, which provide scientific basis for MSW compost utilization and resource in Beijing. The results obtained were as follows:It is predicted that the garbage amount will be 4,530,000 tons in Beijing in 2007 according to the average increase ratio of 2% per year. In the future, the content of ash and clinker will reduce rapidly to minimum, and the amount of food wastes will also have a decreasing tendency. At the same time, paper, clout, plastic and metal wastes will increase, while glass and wood wastes will decrease. Compost production can be consumed l,850,000t every year if it is only fertilized in non-food chain lands such as woodland and grassland. By then the refuse composting will account for 28% of total amount of garbage production if all of the degradable components would be used to make compost. The garbage only could be screened according to different granularity in the pre-treatment in MaJiaLou sorting station, but organic and inorganic components, hard and soft materials in MSW could not be separated.The percentage of degradable components in the composting materials of granularity 15~60 mm was above 60%. During composting in tunnel, the content of the undegradable components increased instead of the degradable components. pH of mature compost was about 8.0, EC was below the plant limits and will not produce salt toxic action. Seed germination at 24h showed the maturity time of garbage composting may be shorten to five weeks from eight weeks. During the composting, the contents of total organic carbon (TOC), total nitrogen (TN)and C/N ratio had a decreasing tendency, while The contents of P, nutrient element (Fe, Ca, Mg, Zn, Cu, Mn) and the heavy metals (Cd, Pb, Cr) increased. The heavy metals content in the garbage compost were lower than those recommended in the National Standards on use in agriculture (GB 8172-87) .The organic matter content of oversized compost in screen was higher than that of undersized compost in the maturity compost. C/N ratio of 12mm oversized compost was higher than that of 12mm undersized compost, there was no obvious difference between 12mm and 5mm undersized compost. The content of K rose with the decreasing of granularity, while the content of other nutrient elements and heavy metals had a decreasing tendency. By adding night soil, TOC of garbage compost were found not to be increased, instead of the contents of TN, while C/N of garbage compost was decreased. P, K and microelement of two undersized composts added with night soil had a corresponding increase. Thecontent of Pb and Cr had no obvious difference between the initial compost treatment and the compost treatment added with night soil, but the content of Cd had a little decrease. The content of Cd, Pb and Cr in the compost treated with night soil satisfied the refuse farmland use standard.The results of summary questionnaires showed that chief measures of increasing compost quality: Manual and mechanical sorting must be strengthened; Separating equipment has to be added to get rid of hard particles (stone, glass, brick); organic materials including straw, leaves and saw-dust should be added to garbage as raw materials;. At the same time, 5mm undersized compost made with 12mm undersized compost will...
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