Experimental study on electrical resistivity of municipal solid waste

Based on the classification of its particle sizes, the electrical resistivity properties of municipal solid waste (MSW), collected from Chongqing landfills are studied. The effects of various factors (solution, porosity, moisture content and temperature, etc.) on the electrical resistivity of MSW are tested indoors. The test results show that when more pollutants are added to the specimens, such as oil pollutant, NaCl, ZnCl₂ and leachate solution, a decrease trend is observed for the electrical resistivity with the increase of porosity in the waste. Supposing the porosity of landfills keeps constant, the proportion of bulk that the circuit of water and solid particles connects in parallel increases with the increase of moisture content in the waste. Meanwhile, the effect of leachate on the resisitivity mainly depends on the dilution degree of leachate, and a decrease is obtained for the electrical resistivity with the increases of moisture content in refuse. Temperature tests indicate that the correlation between electrical resistivity and temperature can be expressed as attenuation exponential function. When the moisture content keeps constant, three kinds of conductive models may be mutually transformed in the waste with the change of porosity of MSW, and it eventually causes the change of electrical resistivity. Finally, a high-density resistivity chromatography is applied in the field tests. The test results can be applied for analyzing the enriched degree and migration path of leachate in the waste mass due to the process of biodegradation of MSW, and they are in favor of evaluating the change of inter-structure of MSW.