大庆油田二类B油层聚驱剖面动用规律及其改善
Producing Patterns and Improvement of Polymer Flooding Profile in Class ⅡB Reservoir,Daqing Oilfield
周丛丛 1曹瑞波 1孙洪国 1樊宇 1郭松林 1梁国良1
作者信息
- 1. 中国石油 大庆油田有限责任公司 勘探开发研究院,黑龙江 大庆 163712
- 折叠
摘要
大庆油田聚合物驱应用规模不断扩大,开发对象转向性质较差的二类B油层,现有聚合物与油层适应性不强,剖面动用规律不明确,不同地区聚驱开发效果差异较大.针对上述问题,应用矿场剖面数据统计和室内实验分析,研究了二类B油层剖面动用规律和剖面改善方法.结果表明:从吸水层动用情况来看,喇嘛甸地区由于发育厚层河道砂,油层物性好,油层有效厚度动用比例最高,油层以多次动用为主,突进层多,相对吸液量高;萨中和萨南地区河道砂发育规模小,薄砂层较多,物性差,有效厚度动用比例较低,但聚驱后,有效厚度动用比例相比水驱分别增大了12.5%和15.4%,渗透率为100～300 mD的储集层吸入剖面改善明显;从未吸水层动用来看,二类B油层纵向非均质性强,导致层间有效厚度未动用比例较高,剖面改善应以均衡层间动用为主;抗盐聚合物高、低质量浓度交替注入可延缓含水率上升时间,增加低渗透层吸液量,聚驱采出程度提高显著.在喇嘛甸北北块A区开展了DS1200抗盐聚合物和高、低质量浓度交替注入试验,降水增油效果好,可为大庆油田二类B油层聚驱剖面改善提供技术指导.
Abstract
The application of polymer flooding is expanding in Daqing oilfield,with the target transferring to poor-quality Class ⅡB reser-voir.The existing polymers exhibit poor compatibility with the reservoir,the producing patterns of the profile remain unclear,and the ef-fects of polymer flooding development vary greatly in different areas.To address these issues,through the analysis of field profile data sta-tistics and laboratory experiments,the producing patterns and improvement methods for the profiles in Class ⅡB reservoir were investigat-ed.In view of the producing status from water-injected layers,Lamadian area which is characterized by thick channel sandbodies and good reservoir properties exhibits the highest proportion of net pay producing,with the reservoir exploited frequently,multiple polymer break-through layers,and relatively high liquid absorption.The Sazhong and Sanan areas,with limited channel sandbodies and multiple thin sand layers with poor properties,show a low net pay producing proportion in the water flooding stage,after polymer flooding which is 12.5%and 15.4%higher than those in the water flooding stage,respectively.Additionally,the reservoirs with permeability ranging from 100 to 300 mD show a significant profile improvement.In view of the producing status of water-unswept layers,the strong vertical heterogeneity of Class ⅡB reservoir results in a high net pay unproducing proportion between layers.In this case,the profile should be improved by achiev-ing balanced interlayer production.The alternating injection of salt-resistant polymer of high and low concentrations can delay the rise of water cut,enhance the liquid absorption in low-permeability layers,and significantly improve the recovery efficiency of polymer flooding.A pilot test on alternating injection of DS1200 salt-resistant polymer of high and low concentrations was conducted in A area of Beibei block in Lamadian,achieving satisfactory water-cut reduction and oil increment.This technology provides a guidance for improving the polymer flooding profiles of Class ⅡB reservoir in Daqing oilfield.
关键词
大庆油田/二类B油层/聚合物驱/吸水剖面/驱油实验/抗盐聚合物Key words
Daqing oilfield/Class ⅡB reservoir/polymer flooding/water injection profile/oil displacement experiment/salt-resistant polymer引用本文复制引用
基金项目
国家科技重大专项(2016ZX05054)
出版年
2024
NETL
NSTL
万方数据