盐穴地下储油库热质交换及蠕变

为了确保盐穴储油库的密闭性和安全性,建立了油、卤水和围岩的热交换模型以及由于温度变化而引起的溶腔压力变化模型,同时建立了岩盐蠕变和渗透模型.通过TDMA算法对模型进行了求解,结果表明,油在7 a的放置过程中,温度升高了8.635℃,压力升高了8.97 MPa,即温度升高1℃压力约升高1 MPa.另外,盐穴的蠕变量随着放置时间的增加而减小.岩盐的渗透率很小,油的渗透量可以忽略.温度变化对溶腔压力有重要的影响,油和卤水的热膨胀系数与可压缩系数的比值决定了温度变化对压力的影响程度.在实际注油时,要准确测量油和卤水的可压缩系数和热膨胀系数,以便对溶腔内液体的温度和压力做出正确的预测和判断.

Heat and Mass Transfer and Creep in Underground Oil Storage with Cavern

To ensure cavern tightness and safety, the models of heat transfer between oil, brine and surrounding rock, thermal pressurization rate, halite creep, and seepage were established and TDMA algorithm was adopted to solve them. The results suggest that the temperature and the pressure will increase by 8. 635℃ and 8.97 MPa in seven years storage process, respectively, i. e. , an approximate value of 1 MPa/℃. The creep rate will decrease with the increase in storage time, and the penetration could be neglected due to little penetrability. In addition, temperature will have significant influence on the cavern pressure and the influence will be determined by the ratio between the thermal expansion coefficient and the compressibility factor (α/β) of both oil and brine. It appears that the thermal expansion coefficient and the compressibility factor of both oil and brine should be measured precisely so that the liquid temperature and pressure in caverns can be predicted accurately.