摘要
低渗透油藏开发过程中往往会进行近井增产措施,此时措施范围内的地层渗透率会得到相应的改变,基础水平井产能公式计算出的产能误差会增大。根据后效射孔技术能提高近井区域渗透率2~3倍的应用效果,分区建立产能模型减小计算误差。射孔弹穿深范围以内为改善后的近井高渗储层区,射孔弹穿深范围以外为原生储层区。根据渗流在空间的连续性原理,将渗流看作由两个方向流动的合成:第一个方向是流体由油藏供给边缘向水平井近井区的平面流动;第二个方向是流体由水平井近井区向井底的径向流动。垂直面内流动可以细分为三部分:首先流体从近井区向圆形等压边界流动,再从圆形等压边界向近井高渗储层区外缘流动,最后从近井高渗储层区外缘向井底流动。分区建立的产能模型与近井高渗储层区渗透率以及射孔弹穿深比正相关,符合实际生产。通过对比分析油田实际生产数据,产能模型预测结果准确度较高,相对误差在10%以内。
Stimulation near wellbore area is often done during the development of low permeability reservoirs.At that time,the formation permeability within the scope of the measures will be changed accordingly.The er-ror of the productivity calculated by the productivity formula for basic horizontal well will increase.According to the application result that the after-effect perforation technology can improve the permeability of the area near wellbore by 2 to 3 times,the regional productivity model is established to reduce the calculation error.The improved reservoir area near wellbore with high permeability is within the range of perforation depth,and the primary reservoir area is beyond the perforation depth.According to the principle of continuity of flow in porous media in space,the flow is regarded as a combination of the one in two directions.One is the plane flow of fluid from the supply edge of the reservoir to the wellbore area of the horizontal well at the first direction.The other is the radial flow of fluid from the wellbore area to the bottom hole of the horizontal well at the second direction.The flow on the vertical plane can be subdivided into three parts.First of all,the fluid flows from the near wellbore area to the circular isobaric boundary.And then it flows from the circular isobaric boundary to the outer edge of high permeability reservoir area near wellbore.Finally,it flows from the outer edge of the high permeability reservoir area near wellbore to the bottom hole.The regional productivity model is positively related to the permeability and perforation depth ratio of the high permeability reservoir area near wellbore,which accords with the actual production situation.Through the comparative analysis of the actual production data of the oilfield,the prediction result of the productivity model is more accurate with less than 10%of the relative error.
作者
杨浩
包智魁
张继成
Yang Hao;Bao Zhikui;Zhang Jicheng(Production Optimization Division,COSL,Tianjing 300451;School of Petroleun Engineering,Northeast Petroleum University,Daqing Heilongjiang 163318)
出处
《中外能源》
CAS
2021年第2期44-49,共6页
Sino-Global Energy
基金
国家“十三五”科技重大专项资助项目“海上三角洲沉积油田整体加密后提高水驱采收率技术研究”(编号:2016ZX05025-001-002)。
关键词
低渗透
后效射孔
产能模型
水平井
low permeable
after-effect perforation
productivity model
horizontal well
