非饱和煤矸石淋滤仪改进及应用

为提升非饱和煤矸石室内淋滤试验的可靠性与准确性,对传统非饱和煤矸石淋滤仪的降雨模拟系统进行改良,实现了随机降雨路径的模拟,并增大了煤矸石有效淋滤体积。同时,以韩城桑树坪煤矿煤矸石为研究对象,揭示了不同降雨强度和风化程度组合条件下煤矸石淋滤特征,试验结果是：(1)淋滤液电导率(EC)及SO4_^2-浓度(c)均随淋滤时间呈整体下降趋势,且可划分为快速下降和缓降趋稳两个阶段；(2)采用指数型函数、傅里叶函数及幂函数对不同试验条件下EC-t和c-t关系曲线进行拟合,拟合函数R_²介于0.87~1.00；(3)167mm/h降雨强度下,淋滤液电导率及SO_4^2-浓度对风化程度的敏感性指数最大,分别为3.14和7.64；(4)相较其它条件下淋滤液电导率及SO_4^2-浓度,83mm/h降雨强度和风化3a矸石条件下淋滤液EC值和c值更高。分析得到三点结论：(1)煤矸石可溶元素释放量主要呈指数型函数衰减,并在试验进行3~5h后趋于稳定；(2)风化程度为影响煤矸石可溶元素释放能力的主控因素；(3)较小的降雨强度和较高的风化程度有利于煤矸石元素持续淋滤释放。

Improvement and application of unsaturated coal gangue leaching instrument

To raise reliability and accuracy of laboratory experiments on unsaturated coal gangue leaching, the rainfall simulation system of traditional unsaturated coal gangue leaching instrument was improved. Thus, the simulation of random rainfall path was achieved, and the volume of coal gangue that can be leached effectively increased accordingly. Meanwhile, the coal gangue in Sangshuping coal mine, Hancheng City, were selected as study objects, and the characteristics of coal gangue leaching under various rainfall intensity conditions and weathering degree conditions were revealed. The results showed that: (1) The values of electrical conductivity (EC) and SO_4^2-concentration (c) of leachate decreased with time. And the process can be divided into quickly falling stage and slowly falling-stabilizing stage. (2) Exponential functions, Fourier functions and power functions were employed to fit the relation curves of EC-t and c-t under different experimental conditions, and the R2 values of fitting functions were 0.87~1.00. (3) With the rainfall intensity of 167mm/h, the values of EC and c of leachate had the highest sensitivity index to weathering degree, namely 3.14 and 7.64. (4) Compared with the other conditions, the combine condition of rainfall intensity of 83mm/h and coal gangue with triennial weathering could produce higher values of EC and c of leachate. Finally, three conclusions were obtained, including: (1) The extraction quantity of coal gangue elements, which tended to be stable in 3~5 hours after the start of experiment, mainly decreased as the exponential function form. (2) Weathering degree was the main control factor that affected the extraction quantity of coal gangue elements. (3) A smaller rainfall intensity or a higher weathering degree was beneficial to consistent extraction of coal gangue elements.