温度、有效应力和含水饱和度对低渗透砂岩渗透率影响的实验研究

为了全面评价温度、有效应力和含水饱和度的变化对砂岩渗透率的影响,实验测定了在不同条件下低渗透砂岩渗透率的变化规律。根据实验结果定性地分析了温度、有效应力和含水饱和度对低渗透砂岩渗透率的影响以及三者之间的相互作用关系。实验结果表明:在有效应力相对较小时温度对渗透率的影响较大,而随着有效应力的增大其作用逐渐减小;随着含水饱和度的增加,温度对渗透率的影响增大;渗透率与有效应力近似呈指数关系变化,但随着温度和含水饱和度的增加需要作校正处理;含水饱和度越高岩石渗透率越低,且随着有效应力的增加,渗透率下降幅度呈递增的趋势,而温度的增加使得含水饱和度越高的砂岩渗透率下降越严重。

EXPERIMENTAL STUDY CONCERNING THE EFFECT OF TEMPERATURE,EFFECTIVE STRESS AND WATER SATURATION ON THE PERMEABILITY OF TIGHT SANDSTONE

In order to generally evaluate the effect of temperature, effective stress and water-saturate to the permeability of tight sandstone, it measured the permeability of tight sandstone at various conditions. It qualitatively analyzed the effect of temperature, effective stress and water-saturate to the permeability of tight sandstone and relationship of them. The experimental result shows that temperature has greater effect on permeability at lower effective stress level but decreases with the increasing of effective stress. Higher of water saturation of sandstone, greater effect of temperature on permeability. The relationship between permeability and effective stress is approximatively exponent but is necessary to correct at high temperature and water-saturate level. Waterermeability greatly decreases when effective stress increased.