增稠剂对膏体充填料浆流动特性的影响及其工程应用

Effect of thickeners on the flow characteristics of paste filling slurry and its engineering application

充填采矿法因其具有大量处置固体废弃物、控制地表沉陷、管理地压等优势广泛应用于地下矿山开采。充填料浆的流动性不仅影响其管道输送,也与充填料浆在空区内的自立性和封堵漏风性能密切相关。本文利用坍落度和稠度测试研究了增稠剂含量和浓度变化对充填料浆流动性的影响,进而分析了增稠充填料浆的自立和防堵漏风性能。在此基础上,开展了增稠膏体充填隅角的工业试验,评估了增稠膏体充填效果。结果表明:20万分子量的羟丙基甲基纤维素(20万HPMC)增稠剂可在10 s内快速溶解,满足连续充填作业的需求。随着20万HPMC含量增加,充填料浆的坍落度和稠度均呈二次多项式函数递减的变化趋势。当增稠剂含量一定,略微提高充填料浆的浓度将显著降低其流动性,改善其在采空区内部的自立能力。依据试验结果,考虑充填料浆在采空区内的自立性和封堵漏风功能,充填料浆的浓度为78%,20万HPMC含量为总固体质量的1‰效果更佳。工业试验结果证实了推荐的配比参数制备的充填料浆在隅角处满足自立性和封堵漏风的要求,隅角充填后CH4和CO浓度减少。研究结果可为充填料浆的增稠和充填技术应用提供参考依据。

The filling mining method is widely used in underground mining due to its advantages of disposing of a large amount of solid waste,controlling surface subsidence,and managing ground pressure.The flowability of the filling slurry not only affects its pipeline transportation,but also is closely related to its self-sufficiency and sealing performance in the empty area.This article uses slump and consistency tests to study the effects of thickener content and concentration changes on the flowability of filling slurry,and further analyzes the self-supporting and anti blocking and air leakage performance of thickened filling slurry.On this basis,industrial experiments were conducted on thickening paste filling corners to evaluate the filling effect of thickening paste.The results show that the 200000 molecular weight hydroxypropyl methyl cellulose(200000 HPMC)thickener can quickly dissolve in 10 seconds,meeting the needs of continuous filling operations.As the content of 200000 HPMC increases,the slump and consistency of the filling slurry show a decreasing trend as a quadratic polynomial function.When the thickener content is constant,slightly increasing the concentration of the filling slurry will significantly reduce its fluidity and improve its self-sustaining ability inside the goaf.Based on the experimental results,considering the self-sufficiency and sealing function of the filling slurry in the goaf,the concentration of the filling slurry is 78%,and the effect is better when the content of 200000 HPMC is 1‰of the total solid mass.The industrial test results have confirmed that the recommended ratio parameters for preparing the filling slurry meet the requirements of self sufficiency and sealing air leakage at the corner,and the CH4 and CO concentrations decrease after corner filling.The research results can provide a reference basis for the thickening of filling slurry and the application of filling technology.