聚合物驱油藏油井堵塞机制与防治

Plugging Mechanism and Prevention of Oil Well in Polymer Flooding Reservoir

刘 盈 陈安胜 王建海 王增宝 程显光 苗雨欣

LIU Ying CHEN Ansheng WANG Jianhai WANG Zengbao CHENG Xianguang MIAO Yuxin

油田广泛长期应用聚合物驱对应的油井堵塞严重，液量下降，严重影响聚合物驱后油藏的进一步开发。针 对胜利油田聚合物驱油藏，利用X射线衍射仪（XRD）、扫描电子显微镜（SEM）等方法分析油井堵塞产物组分与 构成；通过模拟不同堵塞物流体与近井储层条件，研究油井堵塞的堵塞程度与影响主控因素。结果表明，聚合物 驱油藏油井堵塞物主要为发生一定交联并嵌入吸附地层矿物盐、黏土的聚合物团聚体，占比为65.6%；其次为地 层出砂颗粒与胶结物、原油，分别为17.8%、16.6%。地层出砂颗粒造成多孔介质封堵是油井近井堵塞的主控因 素，聚合物衍生交联与吸附团聚形成的聚合物团聚体加剧了油井堵塞程度。基于聚合物驱油藏油井堵塞机制， 实施堵塞油井近井原油清洗+聚合物胶团氧化降解、中远井高效固砂防治的油井解堵防砂一体化防治方案具有 良好的应用效果，平均单井提液86.8%。

Polymer flooding widely used in oilfields for a long time. As a result，there are serious plugging of oil wells and the liquid volume decreased，which seriously affects the further development of reservoirs after polymer flooding. For polymer flooding reservoirs in Shengli oilfield，X-ray diffractometer，scanning electron microscope and other technical means were used to analyze the composition of oil well plugging products. By simulating different plugging fluids and near-well reservoir conditions，the plugging degree and main controlling factors of oil well plugging were studied. The results showed that the plugs in the oil wells of polymer flooding reservoirs were mainly polymer aggregates（65.6%）that were cross-linked and embedded to adsorb formation mineral salts and clays，followed by formation sand particles and cements（17.8%），and crude oil（16.6%）. The plugging of porous media that caused by the formation of sand particles was the main controlling factor of plugging near the oil well. The polymer agglomerates that formed by polymer derivative cross-linking and adsorption agglomeration aggravated the degree of blockage of oil well. Based on the guidance of the research on plugging mechanism of polymer flooding reservoirs，the integrated prevention and control program of oil well plugging and sand control，which was composed of crude oil cleaning and oxidative degradation of polymer micelles in near well，and effective sand consolidation control in far well，had good application effects. The average single well extraction was 86.8%.

10.19346/j.cnki.1000-4092.2022.03.009