二类油层弱碱三元复合驱合理注采井距研究  

Research on Reasonable Producer-Injector Spacing During Weak Alkali ASP Flooding in Class Ⅱ Reservoirs

作　　者：陈喜波[1] 

机构地区：[1]大庆油田有限责任公司第三采油厂,黑龙江大庆163113

出　　处：《中外能源》2015年第5期46-50,共5页Sino-Global Energy

基　　金：国家"十二五"重大专项"大庆长垣特高含水油田提高采收率示范工程"(项目编号:2011ZX05052003)部分研究成果

摘　　要：东部老油田一类油层聚合物驱油经过多年高速开采,产量已逐年减少,要保持油田高效稳产,二类油层三次采油势在必行。随着油田开发的不断深入,二类油层三元复合驱已发展为较成熟的三次采油技术。试验区油层沉积环境为河流-三角洲沉积,属于碎屑岩储油层,纵向上小型河道砂体发育,河道砂体规模较小,连通性差。研究表明,175m井距条件下油层导流能力仍然较弱,聚驱控制程度较低,不适应目的层三元驱的开采。针对试验区发育及开发特点,通过虚拟布井、数值模拟等方法 ,确定了二类油层弱碱三元驱合理注采井距为125m。结果表明,125m井距聚驱控制程度大于70%,油层能够建立较高的驱动压力梯度,并且具有较强的注采能力和最佳的经济效益。在目前条件下,采收率可提高18.6个百分点,税后内部收益率为19.7%,财务净现值为9527.2万元。The output of class I reservoirs in the eastern old oil fields has decreased year by year after many years of high speed production by polymer flooding.Tertiary recovery must be done in class Ⅱ reservoirs now.ASP flooding in the class Ⅱ reservoirs has been developed as mature tertiary recovery tech- nology with oilfield development.The reservoirs in the experimental area deposited in river-delta with the lithology of clastic rocks.The channel sand scale is small and its connectivity is poor.Flow capacity of the reservoirs in the condition of 175m producer-injector spacing is still poor.It is not suitable for the tertiary recovery for low control degree of polymer flooding.Reasonable producer-injector spacing for weak alkali ASP flooding in the class 11 reservoirs is fixed as 125m after the method of virtual well pattern and numerical simulation is applied according to the development features of the experimental area.The control degree of polymer flooding is more than 70% under 125m of well spacing.It achieved high driving pressure gradient, strong injection-production capacity and the best economic benefit.In the current conditions,oil recovery may be enhanced by 18.6% ,after-tax internal rate of return will be 19.7% and financial net present value will be 95272 thousand yuan.

关 键 词：二类油层 三元复合驱 注采井距 采收率 

分 类 号：TE357.4[石油与天然气工程—油气田开发工程]