苏北盆地草舍油田CO_2混相驱替试验与效果分析

苏北盆地草舍油田泰州组油藏为复杂小断块油藏,水驱采收率仅32%。该文通过将CO2混相驱油室内试验和数值模拟结果与矿场试验相结合,进行了开采效果的理论和实际分析与对比。室内试验和数值模拟结果研究表明,采用CO2混相驱可以使该油藏采收率达到47%,比水驱油的方式提高15%。2005年7月至2009年12月,草舍油田泰州组油藏已累计注入CO2气5 842×104m3,增产原油3×104t,提高采收率2%,取得了显著的增产效果。因此,CO2混相驱油是有效的三次采油方法,对复杂断块油藏开展三次采油具有重要借鉴价值。

THE FIELD EXPERIMENT AND RESULTS ANALYSIS OF CO2 MISCIBLE DISPLACEMENT IN CAOSHE OILFIELD OF THE NORTH JIANGSU BASIN

The Taizhou Fm reservoir in Caoshe Oilfield of the North Jiangsu Basin is a complicated and small fault block reservoir,its oil recovery by water displacement is only 32%.Combinating the laboratory and simulation results on CO₂ miscible displacement and field experiment,the theorical and pratical analysis and contrast of oilfield development are accomplished.The oil recovery of this reservoir could be enhanced upto 47% according to results of laboratory experiment and numerical simulation,and higer 15% than water drive.From May 2005 to Dec.2009,the field experiment of CO₂ miscible displacement has been finished in Taizhou Fm reservoir of Caoshe Oilfield,the cumulative amount of CO₂ gas flooding is upto 5 842×104m3,the production of crude oil is increased 3×104t,the oil recovery is enhanced 2%.CO₂ miscible displacement is an effective method of enhancing oil recovery,which has important reference value on tertiary oil recovery in complicated and fault block reservoirs.