类煤岩材料瓦斯吸附特性影响因素试验

Study of gas adsorption characteristics of coal-like materials with influence factors

为研究固-气耦合物理相似模拟试验中模拟煤层材料的瓦斯吸附问题,根据孔隙特征及吸附特征,选择活性氧化铝、硅胶、3A分子筛、4A分子筛、5A分子筛作为吸附材料以及艾维尔沟1890矿煤样为对比材料,采用WY-98A瓦斯吸附常数测定仪对以上材料开展不同温度、粒径、含水率下瓦斯吸附规律试验.结果表明,3种分子筛在各因素影响下的吸附规律不完全符合Langmuir吸附模型,不能作为吸附材料;活性氧化铝和硅胶与艾维尔沟1890矿煤样的瓦斯吸附量比值随压力增大逐渐减小并稳定在0.8至2.7之间且比值趋于常数,因此吸附规律与艾维尔沟1890矿煤样较为相似;多因素影响下煤样与硅胶和活性氧化铝的吸附常数a值的变化趋势相同,但硅胶的变化规律更接近煤样且压力在6 MPa以下瓦斯吸附量大、可调节范围广,所以优先考虑硅胶作为吸附材料.试验材料对温度、粒径、含水率的敏感性各不相同.

To investigate the gas adsorption problem of simulating coal seam materials in solid-gas coupling physical similar simulation experiment,selected activated alumina,silica gel,3 A molecular sieve,4 A molecular sieve,5 A molecular sieve as adsorption materials and Aiweiergou 1890 coal samples as compared materials according to its pore structure and adsorption characteristics.The WY-98 A constant gas adsorption analyzer was used to carry out adsorption experiment for samples with different temperature,particle size and moisture content.The results show that adsorption laws of three kinds of molecular sieves under multiple factors don’t fully conform to Langmuir adsorption model and can’t be used as adsorption materials.The changing trend of adsorption increment of activated alumina,silica gel is similar to that of coal samples and the adsorption ratio between aiweiergou 1890 coal and those waves from 0.8 to 2.5 and trend to be a constant with the increase of pressure.The adsorption laws are similar to coal samples.The gas adsorption constant a value changing trends with various factors of activated alumina,silica gel are the same to aiweiergou 1890 coal but the change law of silica gel is closer to that of coal samples.The adsorption amount below 6 MPa is large and it can be adjusted to a wide range.Therefore,silica gel is preferred as an adsorption materials.Testing materials have different sensitivities to temperature,particle size and moisture content.