1 Geotechnical Engineering Research Institute, Hohai University, Nanjing, China.
2 Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Nanjing, China.
Waste Manag Res. 2018 May;36(5):463-470. doi: 10.1177/0734242X18766223. Epub 2018 Apr 7.
The air permeability coefficient has a high correlation with the water content of municipal solid waste. In this study, continuous drying methodology using a tension meter was employed to construct the soil water characteristic curve of municipal solid waste (M-SWCC). The municipal solid waste air permeability test was conducted by a newly designed apparatus. The measured M-SWCC was well reproduced by the van Genuchten (V-G) model and was used to predict the parameters of typical points in M-SWCC, including saturated water content, field capacity, residual water content and water content at the inflection point. It was found that the M-SWCC was significantly influenced by void ratio. The final evaporation and test period of M-SWCC increase with the increase in void ratio of municipal solid waste. The evolution of air permeability coefficient with water content of municipal solid waste depicted three distinct characteristic stages. It was observed that the water contents that corresponded to the two cut-off points of the three stages were residual water content and water content at the inflection point, respectively. The air permeability coefficient of municipal solid waste decreased with the increase of the water content from zero to the residual water content. The air permeability coefficient was almost invariable when the water content increased from residual water content to the water content at the inflection point. When the water content of municipal solid waste exceeded the water content at the inflection point, the air permeability coefficient sharply decreased with the increase of water content.
透气性系数与城市固体废物的含水量具有高度相关性。本研究采用张力计连续干燥法构建了城市固体废物(M-SWCC)的土壤水分特征曲线。通过新设计的装置进行了城市固体废物透气性测试。所测量的 M-SWCC 通过 van Genuchten(V-G)模型得到了很好的再现,并用于预测 M-SWCC 中典型点的参数,包括饱和含水量、田间持水量、残余含水量和拐点处的含水量。结果表明,M-SWCC 受空隙比的显著影响。随着城市固体废物空隙比的增加,M-SWCC 的最终蒸发和测试时间增加。透气性系数随城市固体废物含水量的变化描绘了三个明显的特征阶段。观察到三个阶段的两个截止点对应的含水量分别为残余含水量和拐点处的含水量。城市固体废物的透气性系数随着从零到残余含水量的含水量增加而降低。当含水量从残余含水量增加到拐点处的含水量时,透气性系数几乎不变。当城市固体废物的含水量超过拐点处的含水量时,透气性系数随着含水量的增加而急剧下降。