温度和塑料含量对垃圾土气相渗透特性影响的试验研究

Experimental study on effect of temperature and plastic content on air permeability of municipal solid waste

为研究温度和塑料含量对垃圾土气相渗透特性的影响,研制了一种可温控的垃圾土气相渗透仪.通过重复试验以及与现有的常温试验结果进行对比,验证了试验的可重复性和可靠性.通过控制垃圾土试样不同的孔隙比、温度以及塑料含量,开展一系列气相渗透试验,探究孔隙比、温度和塑料含量对垃圾土气相渗透系数的影响规律.结果表明:随着孔隙比的增大,垃圾土气相渗透系数增大明显,当孔隙比从1.5增大至3.5时,垃圾土气相渗透系数增大了22倍;在填埋场常见的20~60℃温度区间中,随着温度的升高,气相渗透系数逐渐增大;随着塑料质量分数从10%增大到15%,气相渗透系数相应增大;而塑料质量分数从15%增大到30%,气相渗透系数则逐渐减小.试验结果可为填埋场气体运移参数的选取提供参考.

To study the effects of temperature and plastic content on air permeability of municipal solid waste(MSW),a temperature-controlled gas permeameter for MSW was developed.The repeatability and reliability of the test was verified by repeated tests and comparison with results of normal temperature tests.A series of air permeability tests were carried out by controlling different void ratio,temperature and plastic content of MSW samples.The effects of void ratio,temperature and plastic content on the air permeability of MSW were investigated.The results show that the air permeability of MSW increases obviously with the increase of void ratio.The air permeability of MSW has a 22-fold increase with the increase of void ratio from 1.5 to 3.5.In the common temperature range of landfills,i.e.,20℃to 60℃,the air permeability of MSW increases gradually with the increase of temperature.The air permeability of MSW increases with the increase of plastic mass fraction from 10%to 15%.However,the air permeability of MSW decreases with the increase of plastic mass fraction from 15%to 30%.The results can provide a reference for the selection of gas migration parameters in landfills.