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At present, domestic and landfill leachate collection and drainage system generally prone to clogging, resulting in the leachate water level is too high, which has become a major problem on the international. Landfill guide row layer of the clogging mechanism, the calculation of the maximum water level of the guide row layer clogging conditions, reduce clogging, optimize design has important practical significance. To solve this problem, this paper summarizes the status and method of clogging research at home and abroad, as well as related site excavation, laboratory test data, combined with the latest understanding of the clogging mechanism of these three factors, temperature, particle size, geotextile, and combinations thereof, designed pilot programs, research and development and test equipment, successfully carried out a long-term test. After a preliminary analysis of the test results found that trials (over 300 days), the coarse-grained group drainage porosity and fine-grained group gradually reduced over time, at different temperatures and geotextile coarse group The the drainage porosity are greater than the fine-grained group dominated visible particle size of clogging. Test group of the same particle size and geotextile set at different temperatures, the drainage porosity and no obvious difference; decrease in the test group set to the same temperature and the geotextile, coarse particle size and the fine particle size particles porosity similar percentage (about 10%), but the coarse particle size reduction in absolute greater than the fine group, i.e. coarse particles more voids occupy clogging matter; same particle diameter under the conditions in the same temperature, with and without geotextile cloth drainage porosity is not yet evident. Changes in the chemical composition of the group of test is not very different. On this basis, the paper combined with previous research results of the research group, as well as the latest international research progress, clogging conditions under the highest water level simplified model and control equation proposed numerical method for the calculation of the highest water level in the clogging conditions and stability state and transient methods were compared. The results show that, without clogging the results obtained with the transient consistent results, and tends to a steady-state results; clogging is more serious when the water level to be significantly affected, we must consider the clogging. Found by the parametric analysis, the initial permeability coefficient, clogging smaller impact on the water level, but over time clogging affect larger growth; drain the longer the distance, the infiltration faster, the higher the concentration of ions, then the silt blocking the more serious impact on the water level. Consider clogging conditions under design recommendations to improve the drainage system. Finally, binding experiments and numerical analysis results, the clogging of the impact factors and to reduce clogging optimal design measures to control the water level guarantee the landfill hygiene, safe operation.
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