江桥稠油油田水平井蒸汽吞吐数值模拟研究

针对江55块浅薄层稠油油藏直井开采难度大,经济效益差的特点,利用油藏数值模拟技术进行了水平井蒸汽吞吐开发效果研究及注采参数优化设计。数值模拟结果表明,对水平井蒸汽吞吐效果而言,井网1和井网2的开发效果相差不多,可根据实际情况选用;井距越大,采出程度越低。井距增加4倍,采出程度下降10%。结合理论计算和数值模拟结果,优选125m为水平井蒸汽吞吐最佳井距。周期注汽量越大,加热范围越大,采出程度增加,但是油汽比降低。兼顾二者,优选周期注汽量3 600 m3。随着蒸汽干度和焖井时间的增大,采油量增加,蒸汽干度最少在0.4以上,焖井时间要控制在合理范围15 d左右。

A Study on Numerical Simulation of Steam Stimulation by Horizontal Well for Recovering Heavy oil in Jiangqiao Oilfield

In the purpose of solving the problem of poor economic benefit using vertical well to recover heavy oil in Jing55 Block reservoir, numerical simulation technologies were used to evaluate the development effect of steam stimulation using horizontal well and optimize the injection and production parameters. The numerical simulation results showed that well pattern 1 and well pattern 2 had a close development effect in steam stimulation of horizontal well, which could be chosen on the basis of actual situation. The more the well distance was, the lower the degree of reserve recovery was. When the well distance increased quadruple, the degree of reserve recovery decreased by 10%. 125m was determined to be the best well distance in accordance with numerical simulation and theoretical calculation. 3600m3 was determined to be the best injection amount of steam with the degree of reserve recovery and oil/steam ratio taken into account. Steam quality and stimulation time were determined to be 0.4 and 15d, respectively.