我国填埋场污泥土工特性研究

Research on the Geotechnical Characteristics of the Landfill Sludge in China

填埋场污泥由于储量巨大、强度低且持续产生有毒有害气体,因此亟待处理。为研究其特性,利用现场取样与十字板剪切试验对我国几个填埋场内的贮存污泥和处理污泥的原位性质进行分析,并通过密度试验、含水率试验、有机物含量试验和直剪试验对污泥的土工特性进行检测。基于现场测试和室内试验对不同来源、不同处理方式的污泥进行分析总结发现:填埋场中贮存污泥的平均含水率最高达1363.48%;平均有机物含量为38.94%~45.28%;平均密度接近1.00 g/cm3,最高为1.11 g/cm3。贮存污泥的黏聚力接近于0,摩擦角为13.80°~16.05°。与贮存污泥相比,处理污泥的含水率减小,平均含水率在440%以下,最小值为76.24%。同时,其平均有机物含量为11.76%~22.98%;平均密度为1.19~1.57 g/cm3。不同处理方式对污泥的强度有不同程度的提高,其中固化污泥的强度增强效果最突出,平均黏聚力最大可达54.01 kPa。

Landfill sludge is in urgent need of treatment due to its huge reserves,low intensity,and continuous production of toxic and harmful gases.The in-situ properties of storage sludge and treated sludge in several Chinese landfills were analyzed by on-site sampling and vane shear test.And the geotechnical characteristics of sludge were tested by density test,water content test,organic matter content test and direct shear test.Based on the field and laboratory tests,the characteristics of sludge from different sources and different treatment methods were analyzed and summarized.It was found that the average water content of the storage sludge in landfill was up to 1363.48%.The average organic matter content was 38.94%~45.28%.The average density was close to 1.00 g/cm3,and the highest was 1.11 g/cm3.The cohesion of the storage sludge was close to 0,and the friction angle was 13.80°~16.05°.Compared with storage sludge,the water content of treated sludge was reduced,the average water content was below 440%,and the minimum was 76.24%.Meanwhile,its average organic matter content was 11.76%~22.98%,and the average density was 1.19~1.57 g/cm3.Different treatment methods could improve the strength of sludge to different degrees,among which the strength enhancement effect of solidified sludge was the most prominent,with an average cohesive up to 54.01 kPa.