摘要
针对土工织物用于铝尾矿赤泥库排水反滤时易发生淤堵的问题,采用4种典型土工织物和赤泥进行改进梯度比试验,通过分析梯度比和渗透系数变化规律揭示土工织物/赤泥系统的淤堵特性,通过分析赤泥颗粒迁移规律对土工织物用于赤泥的排水反滤机理进行初步探讨。结果表明:随着水力坡降的增大,4种土工织物系统的梯度比会大于临界值3,但3种无纺土工织物系统的渗透系数会略微降低,而复合土工织物由于自身特殊的孔隙结构,系统的渗透系数呈增大的趋势;仅通过分析梯度比的变化规律无法准确判断土工织物/赤泥系统的淤堵特性,需结合系统渗透系数的变化趋势进行综合判断;土工织物表面滤饼的形成是其能够用于赤泥排水反滤的关键,滤饼虽然会降低系统的渗透性,但能够明显提高系统的保土性。
Aiming at the clogging problem of geotextile used as filtration of aluminum tailings reservoir,the modifiedgradient ratio tests were conducted on the four typical geotextiles and red mud system. The clogging property of the geotextile/red mud system were evaluated by analyzing the tested results of gradient ratio and permeability coefficient. The filtrationmechanism of the geotextile on red mud were preliminarily discussed by analyzing the migration behaviors of red mud parti-cles. The tested results show that the gradient ratio of the four geotextile/red mud systems is greater than the critical value 3 with the increase of the hydraulic gradient. However,the permeability coefficient of the three non-woven geotextile systemsdecreases slightly. Herein,the permeability coefficient of the composite geotextile systems show a tendency to increase dueto its special pore structure. The traditional method on basis of the variation rule of the gradient ratio to judge the cloggingproperty of geotextile/red mud system is inaccurate. It is necessary to make a comprehensive judgment based on the variationtendency of the permeability coefficient. The formation of filter cake on the geotextile/red mud interface is the key to makesuccessful filtration. Although the filter cake may reduce the permeability of the system,it can obviously improve the soil re-tention of the system.
作者
程醒
吴海民
易有元
田振宇
毛文龙
CHENG Xing;WU Haimin;YI Youyuan;TIAN Zhenyu;MAO Wenlong(College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China;Nanjing Rightway Environmental Research Institute Co.,Ltd,Nanjing 211100,China)
出处
《金属矿山》
CAS
北大核心
2020年第12期196-202,共7页
Metal Mine
基金
中央高校基本科研业务费专项资金项目(编号:2016B40814)。
关键词
土工织物
赤泥
梯度比试验
排水反滤
淤堵
渗透性
feotextile
red mud
fradient radio test
filtration
clogging
permeability
