煤岩受载过程与瓦斯渗透特性映射规律试验研究

Title

Experimental study on mapping mechanism of loading process of rock and coal and gas permeability
作者

邹银辉程波
Author

ZOU Yinhui,CHENG Bo
单位

瓦斯灾害监控与应急技术国家重点实验室中煤科工集团重庆研究院有限公司
Organization

1. National Key Laboratory of Gas Disaster Detecting, Preventing and Emergency Controlling, Chongqing , China; 2. Chongqing Research Institute,China Coal Technology and Engineering Group,Chongqing , China
摘要

为研究煤岩受载过程与瓦斯渗透特性的映射规律，利用自主研发的可连续实施约束环形应变与轴向受载的煤岩瓦斯渗流试验系统，对原煤试件首先实施约束环形应变条件下不同瓦斯压力、不同压差的渗透特性测试，之后对其施以轴向压力，分析煤岩试件在受载过程中的瓦斯渗透特性。结果表明：在约束环形应变条件下的含瓦斯煤渗透特性测试中，随着煤岩吸附瓦斯含量的增加，试件的渗透率逐渐降低，且二者之间较好地服从幂函数的数学关系，这与前期研究成果的结论一致；轴向应力的添加使得渗透率降低了近1个数量级；有效应力对煤岩渗透特性的“负作用”效应强于吸附作用的“正作用”；建立了煤岩受载全过程的瓦斯流动模型，并将瓦斯在煤体内的流动按照受载情况分为3个阶段。建立的煤岩瓦斯气体流动模型对表征煤岩不同受载条件下的运移特征更为完整，使渗流阻力组成更清晰，物理意义更明确。
Abstract

The research focuses on the mapping mechanism of load process of rock and coal and gas permeability. An experimental system was developed to test the permeability of raw coal samples under different gas pressures and pressure differences. The system can continuously implement constrained annular strain and axial loading. The coal samples were tested under constrained annular strain conditions and then adding axial pressure. The results show that, under constrained annular strain, the permeability decreases gradually with the increase of gas adsorbed by coal and rock, proportional to a power function, which agrees with the previous research results. The results also indicate that the addition of axial stress reduces the permeability by nearly one order of magnitude. The negative effect of stress on the permeability of coal and rock is stronger than the positive effect of adsorption. Furthermore, a gas flow model for the whole loading of coal and rock was established, in which the gas flow in coal was divided into three stages according to the loadings. The gas flow model of coal and rock has physical significance, which represents the migration of coal and rock under different loadings commendably and describes the composition of seepage resistance clearly.
关键词

瓦斯吸附非线性渗流渗透率轴向受载
KeyWords

gas adsorption; nonlinear seepage; permeability; axial loading
基金项目(Foundation)

国家自然科学基金面上基金资助项目（51774319）
图表
图(6) / 表(0)