电热高温场下密闭区低透卸压突出煤层瓦斯渗透耦合机制研究

The project is for the problem of remaining difficulty of of gas predrainage in low-permeability outburst coal seam in China (especially in Guizhou province),put forward a new using method of electrothermal high-temperature field gas drainage outburst prevention and outburst coal seam gas using in the protected pressure relief low-permeability outburst coal seam.The project researches the three field coupling effect of low stress field,electrothermal high temperature field and gas seepage field in the low-permeability outburst coal seam of mining face,analyzing the influence factors of heat conduction in the low-permeability outburst coal seam,study on the features and the main control factors of the electrothermal high temperature field in the mine gas drainage faces.Based on the cement tank simulation electrothermal high temperature field experiment and numerical simulation model of the low-permeability outburst coal,establishing electrothermal high temperature field with the best gas drainage effec of the advance borehole in the low-permeability outburst coal seam in the mining face sealing zone.Through the parameter of the gas drainage concentration of predrilling advance single borehole in the working face,the gas flow of the advance single borehole,and the total recovery of coalbed methane,evaluating method of mine electrothermal high temperature field gas drainage preventing the outburst and the feasibility of new technology of coal and gas mining.The project provides a new technology of gas drainage and the gas utilization in low-permeability outburst coal seam for our country.After project implementation, we can economic and effectively coupling effected of the gas permeability in low-permeability outburst coal seam,and increasing the output of clean energy of the coalbed methane in China.The research project also provides the research direction for the cross development.

本项目针对我国（特别是贵州省）煤矿低透突出煤层瓦斯抽放仍然难的问题，提出了被保护卸压开采的低透突出煤层电热高温场瓦斯抽排放防突和煤层气利用新方法。本项目研究矿井采掘工作面低透突出煤层低应力场、电热高温场和瓦斯渗流场三场耦合作用机制，分析矿井低透突出煤层热传导影响因素，研究矿井瓦斯抽排放工作面电热高温场特征及主控因素。基于室内水泥槽低透突出煤层煤样电热高温场模拟实验和数值模拟，构建矿井采掘工作面密封区低透突出煤层超前钻孔最佳瓦斯抽排放效果电热高温场，通过现场实测该工作面超前钻孔单孔瓦斯抽排放浓度、单孔瓦斯抽排放流量及煤层气共采总量等参数，效果评价矿井电热高温场瓦斯抽排放防突法及煤与瓦斯共采新技术可行性。本项目研究为我国低透突出煤层瓦斯抽采和煤层气利用提供了新技术，项目实施后可经济有效地耦合煤矿低透突出煤层瓦斯解吸渗透，增加我国洁净能源煤层气产量。该研究项目也为学科交叉发展提供了研究方向。

本项目针对我国煤矿低透突出煤层瓦斯抽放仍然难的问题，提出了被保护卸压开采的低透突出煤层电热高温场瓦斯抽排放防突和煤层气利用新方法。本项目研究了矿井采掘工作面低透突出煤层低应力场、电热高温场和瓦斯渗流场三场耦合作用机制，分析了矿井低透突出煤层热传导影响因素，研究了矿井瓦斯抽排放工作面电热高温场特征及主控因素。基于室内水泥槽低透突出煤层煤样电热高温场模拟实验和数值模拟，构建了矿井采掘工作面密封区低透突出煤层超前钻孔最佳瓦斯抽排放效果电热高温场，通过现场实测该工作面超前钻孔单孔瓦斯抽排放浓度、单孔瓦斯抽排放流量及煤层气共采总量等参数，效果评价矿井电热高温场瓦斯抽排放防突法及煤与瓦斯共采新技术可行性。项目获得的重要结果：（1）相同的加热电缆布置方式，随着加热时间的增加，水泥槽煤样温度先快速增加，加热7~10天后煤样温度趋于稳定。(2）同样加热温度和保温隔热条件，三加热电缆布置方式的煤样温度最高，单加热电缆布置方式的煤样温度最低。其中，当三加热电缆布置方式加热温度为300℃时，对应的煤样温度最大达107℃。同一加热电缆布置方式中，加热温度越高，对应的煤样温度也越高。（3）三种实验方案中，均为保温隔热条件下水泥槽煤样温度高。通过对比未注水煤样的电热高温场数据，得知煤样注水对电热高温场加热效果影响明显。本项目研究为我国低透突出煤层瓦斯抽采和煤层气利用提供了新技术，项目实施后可经济有效地耦合煤矿低透突出煤层瓦斯解吸渗透，增加我国洁净能源煤层气产量。该研究项目也为学科交叉发展提供了研究方向。