煤渗透特性及其气体压力敏感性试验研究

发布时间：2018-04-10 15:20

本文选题：煤 + 有效应力　；参考：《中国矿业》2017年06期

【摘要】：为探索煤中孔隙流体压力的变化导致渗透率的改变,引发煤渗透率压力敏感性现象,利用自主研发的出口端压力可调的三轴渗流装置,对贵州3个矿区的煤开展不同吸附性气体与不同气体压力下煤的敏感性试验研究。研究结果表明:在较低气压范围内(0~0.6 MPa),随气体压力的增加,煤渗透率下降明显,当气体压力继续上升煤的吸附作用逐渐趋于平衡,煤体骨架的吸附膨胀变形也越来越小,渗透率的下降速率逐渐减少并趋于平缓。在气体压力小于1.0 MPa时,煤渗透率损害率Dp变化较大,且随气体压力增加快速增大,表现出较强的压力敏感性。不同吸附性气体条件下,气体压力指数关系敏感系数Cp均随气体压力的增加而逐渐减小,煤渗透率对气体压力的敏感性降低。对于同一煤,在相同的条件下,CH4的气体压力乘幂关系敏感系数Sp的值最小,煤对气压的敏感性越差。乘幂关系的气体压力敏感系数Sp与渗透率损害率Dp有很好的线性相关性。
[Abstract]:In order to explore the permeability change caused by the change of pore fluid pressure in coal and the phenomenon of coal permeability pressure sensitivity, a triaxial percolation device with adjustable outlet pressure was developed.The sensitivity of coal under different adsorptive gases and different gas pressures was studied in 3 mining areas of Guizhou province.The results show that in the low pressure range, the coal permeability decreases obviously with the increase of gas pressure, and when the gas pressure continues to rise, the adsorption and expansion deformation of the coal skeleton becomes smaller and smaller.The rate of decrease in permeability gradually decreases and tends to level off.When the gas pressure is less than 1.0 MPa, the coal permeability damage rate DP changes greatly, and increases rapidly with the increase of gas pressure, showing a strong pressure sensitivity.Under different adsorptive gas conditions, the sensitivity coefficient of gas pressure exponent (CP) decreases with the increase of gas pressure, and the sensitivity of coal permeability to gas pressure decreases.For the same coal, the sensitivity coefficient Sp of the gas pressure power relation of Ch _ 4 is the smallest under the same conditions, and the sensitivity of the coal to the pressure is worse.There is a good linear correlation between the gas pressure sensitivity coefficient (Sp) and permeability damage rate (DP).
【作者单位】：贵州大学矿业学院;贵州大学喀斯特山区优势矿产资源高效利用国家地方联合工程实验室;贵州省非金属矿产资源综合利用重点实验室;国家电力投资集团公司贵州遵义产业发展有限公司;
【基金】：国家自然科学基金项目资助(编号:51574093) 贵州省科学技术基金项目资助(编号:黔科合J字[2015]2049号) 贵州省科技厅、贵州大学联合资金计划项目资助(编号:黔科合LH字[2014]7654) 贵州大学引进人才科研项目资助(编号:贵大人基合字[2014]57号)
【分类号】：TD712

【相似文献】