废弃凝析气藏注水开发可行性研究

目前全世界凝析气田开发主要采用衰竭和注气两种开发方式.在我国除少数气田采用注气开采方式以外,衰竭式开采是主要开发方式.注气由于诸多条件的制约,广泛应用受到限制;而衰竭式开采凝析油采收率低,对于凝析油含量高的气藏开采效果不好.注水开发凝析气藏是一新的开发方式,在国内对此方面研究较少,值得探索.此次研究以大港板桥废弃凝析气藏室内岩心注水驱替实验为基础,对水驱的可行性及其机理进行探讨.实验表明:凝析油和天然气的采收率最高可分别增加3.39%和10.11%;较高速度下注水效果好于在低速下水驱效果;存在一最佳注水量;在废弃压力条件下注水效果优于复压后注水效果.

Research of the feasibility of exploiting abandoned condensate gas reservoir by water injection

Because of the economic advantage of natural depletion,most of condensate gas reservoirs are developed by natural depletion in our country.But the natural depletion method leads to lower recovery factor,especially the recovery factor of condensate oil.In order to produce more condensate oil,the feasibility of exploiting the abandoned condensate gas reservoir by water-injection is discussed on the basis of the laboratory core displacement experiments of Banqiao abandoned condensate gas reservoir and material balance analysis.The results of the experiments show that the recovery factors of condensate oil and gas are increased by 3.39% and 10.11% respectively;the result of waterflooding at higher speed is better than that at lower speed,the result of waterflooding at abandonment pressure is better than that at 20 MPa.The results calculated by material balance method are close to the experimental results.The field tests of Banqiao condensate gas reservoir show that,exploiting abandoned condensate gas reservoir by injecting water can not only improve the recovery factor,but also solve the problem of waste water treatment at the same time.