孔隙压力和温度对煤岩中氮气渗流影响的实验研究

Experimental study on effect of pore pressure and temperature on nitrogen flow in coal rock

为了探讨孔隙压力和温度对氮气在煤岩中渗流特性的影响,在恒定有效应力的基础上,利用自主研发的煤岩渗透率实验装置,分别进行了不同孔隙压力和温度下的渗流实验。结果表明:在恒定有效应力下,渗透率与孔隙压力和温度均呈负幂指数关系,煤岩渗透率均随着温度或者孔隙压力的升高先快速降低后逐渐平缓,分别得到实验煤岩孔隙压力和温度对煤岩氮气渗透作用的临界值,并拟合得到渗透率与温度和孔隙压力之间的关系。

In order to investigate the influence of pore pressure and temperature on the permeability of coal rocks, based on the constant effective stress, the experiment of coal rock permeability at different pore pressures and temperatures are carried out with the self-developed coal permeability experiment device. It shows that under constant effective stress conditions, coal rock permeability has a negative power exponential relationship with pore pressure and temperature. With the increase of pore pressure or temperature, the permeability shows a similar change law, which first decreases rapidly and then tends to gently. The critical values of the test coal rock pore pressure and temperature on coal rock nitrogen permeability are obtained;and the relationship between permeability and temperature and pore pressure was obtained.