| In general, there are three main methods to handle the municipal solid waste (MSW) including landfill disposal, compost and incineration. Comparing to the other two methods, the landfill disposal method is the best one for its lower cost and less secondary pollution. It is thus the base of this thesis. However, the existing landfilling method had some disadvantages, such as the slow degradation of MSW, requirement of long time for stable landfill field, difficult treatment and high cost of the leachate and so on. This thesis is thus devoted to solve all above problems. It has studied firstly the characteristics of the bioreactor landfill system (R4) and the bioreactor landfill system with inoculability(R5), compard with the experimental results of the tradition landfill(Rl), humidity adjusted landfill(R2) and the landfill with leachate cycled directly(R3), Secondly, based on suitably recursive model, it a mathematical model to describe the variation of bioreactor landfill system's CODcr and the gas product is built.Thirdly, in order to reduce or restrain the rotten gas pollution of the landfill, it has studied the main compositions, the content and control of the rotten gas of the landfill such as R2,R3 and R4.The main results of this thesis are as followings:1. Two results about the variety of contaminants of each landfill are given.one is that the landfill of Rl, R2 and R3 cannot accelerate the decomposition of refuse at the beginning of experiments just by adjusting the humidity (R2) or recycling leachate (R3) directly , which make the hydrolytic and fermentative microorganism of the landfill increase quickly, because the microorganism just hydrolyzed the refuse, which leaded to organic acid accumulated, pH reduced and ecosystem of methane-producing microorganism destroyed. The other one is that the circumfluenced leachate (R4,R5) after having been treated in the methane-producing reactor could accelerate the decomposition of the refuse and get the stabilization of the landfill immediately, because the decomposition of the refuse came into being two phases: hydrolyzing phase and methane-producing phase. Hydrolyzing reaction was mainly occurred in the refuse reactor, and methane-producing reaction was mainly taken in methane-producing reactor. These two landfill bioreactors have created suitable conditions to the growth of the methanogenic groups and accelerated the stabilization of the landfill.2. The mathematical model can be used to describe the daily variety volume of producing gas and the total variety volume. It could provide valuable reference data for collecting and using of the gas in future.3. COD function has shown that the variation of COD-concentration and the total COD-pollution. It could be used to predict the variation of the degraded refuseof the bioreactor landfill system and provide valuable reference data to later management landfill. Combining COD function with the mathematical model, it could provide theoretical data for the resource reused.4. The characteristics of methane-producing reactor have shown that two phases of the decomposition of the refuse could be achieved by adjusting the humidity of the landfill, the hydraulic load of methane-producing reactor and volumetric COD load. When the pH of the landfill was less than 6.5, and the volumetric COD load of methane-producing reactor was 6.5-7.5 kg/(m3.d), Hydrolyzing reaction was mainly occurred in the refuse reactor, methane-producing reaction mainly produced in methane-producing reactor, which is very useful to collect gas and improve the methane content.5. The pH of landfill will affect the concentration of ammonia and volatile organic acid of the rotten gas of the landfill distinctly. When pH >7, ammonia was the mainly composition of the rotten gas and the content of volatile organic acid was few even nonexistence; However, when pH <7, the conclusion was inverse.6. The variation of concentration of the acetic acid, propyle acid and butyric acid in R2 R3 R4 reactor has shown that the concentration...
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