| The hydraulic characteristics of the landfill body and the physicochemical property characteris-tics varied with the biochemical degradation of the municipal solid waste, which increased the difficulty of the leachate migration discipline. By means of theoretical analysis, simulated experiment and numerical simulation, the effect of biodegradation on the solid matrix of the landfill body and the characteristics of leachate were analyzed. Then the author studied the water and solute migration discipline. considering the degradation of landfill body.Based on the dynamics of water .the author first analyzed the basic theories of leachate migration in landfill body, including the mechanisms of water and solute migration in landfill body. Then the simulated experiment was conducted, analyzing the initial characteristic of the municipal solid waste, the landfill settlement, leachate density and the dominant pollutants concentration in leachate. Based on the experimental study and theoretical analysis, the effect of degradation of organic waste under temperature on leachate migration was studied from the aspects of the solid matrix of the landfill body and the characteristics of leachate. The relative thermodynamic theories were employed in this thesis, the effect of temperature on the equilibrium constant of the typical anaerobic degradation reaction(the methane fermentation phase) and established the quantitative formula between the equilibrium constant and the temperature. Also ,the author primarily discussed the effect mechanisem of temperature in landfill body.Based on analyze the theories of permeability coefficient—Kozeny-Carman. The author take in the theories of experiments on different temperature including water temperature,rock temperature and temperature grads under the definite press,and analyzed effect on the leachate temperature,waste temperature and temperature grads. Finally the effect formulate of the temperature to permeability coefficient of landfill under the level off of seepage.Taking in account of the variety of porosity and hydraulic conductivity in the process of the degradation of organic waste, the water and solute migration model in landfill body was established. The one-dimensional compress model was employed in this thesis. At the same time, taking the COD concentration in leachate as an example, the migration equation of organic pollutants in leachate was established taking in account of degradation of organic waste.The leachate quantity was predicted by the mathematical model. The results showed that due to the obvious heterogeneous of the municipal solid waste in landfill in the initial time, the experimental value and the predicted value had some difference. But in the later time, the experimental value and the predicted value was closer. This research exerts positive effects on the prediction of leachate quantity and quality in landfill and effective control measures for leachate pollution. |
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