基于有效介质理论的煤岩界面识别方法研究

摘要

为解决目前依靠人工进行煤岩界面识别存在的问题,研究煤岩界面的自动识别技术,依据煤岩介电特性的差异,利用Bruggeman有效介质理论,建立基于煤含量检测的煤岩分界模型,并以煤岩混合介质粉末为例,进行试验验证.通过模拟煤含量实时变化的煤岩混合介质,实时地获得煤岩混合介质的相对介电常数,利用上述模型进行混合物煤含量的计算,并与闽值进行比较,判定采煤机截割状态.测试结果表明:在0.01～30 MHz的检测频率内,煤岩混合介质的煤含量均能通过此方法计算得到,在0.5～ 30 MHz内,理论煤含量与实际煤含量的相对误差较小,平均可控制在2.60％以下.该模型的计算结果均可以较准确地识别煤岩界面,为实现井下无人化开采提供一种新的煤岩识别方法.%In order to solve the present problems existed in the coal-rock interface recognition by labor,an automatic recognition technology of the coal-rock interface was studied.According to the differences of the coal and rock dielectric characteristics,the Bruggeman effective medium theory was applied to establish the coal-rock boundary model based on the coal content detection.Based on the coal-rock mixed medium powder as an example,a test was conducted for the verification.With a simulation on the real-time varied coal-rock mixed medium of the coal content,the relative dielectric constants of the coal-rock mixed medium were real timely obtained.The model was applied to the calculation on the coal content of the mixture and a comparison to the threshold value was conducted.Thus the cutting status of the coal shearer was judged.The test results showed that within the test frequency of 0.01 ～ 30 MHz,the coal content of the coal-rock mixed medium all could pass the obtained value calculated with the method.Within the frequency of 0.5 ～ 30 MHz,there would be a small relative error between the theoretical coal content and the actual coal content and could be controlled below 2.60％ in average.The calculation results of the model all could accurately recognize the coal-rock interface and could provide a new coal-rock recognition method to realize a minerless mining in the underground mine.