河南油田微凝胶驱技术的矿场实践与认识

Field practice and understandings of microgel flooding techniquein Henan Oilfleld

微凝胶驱技术(低浓度交联聚合物驱技术)是一项低成本高效益的提高采收率新技术。河南油田在室内研究基础上,系统地开展了微凝胶驱技术的单井试注、单井驱替、多井组驱替等不同规模的矿场试验,展示出明显不同于聚合物驱的动态特征:注入压力上升幅度大,吸水剖面改善幅度比聚合物驱好,产出液聚合物浓度低,见效时间滞后。下二门H_2Ⅲ油组、双河437Ⅱ_(1-2)油组矿场试验注污水配制微凝胶(400 mg/L HPAM、60 mg/L Cr^(3+))0.19～0.37 PV,当量吨聚合物增油85.2～105.3 t,阶段提高采收率6.01%～7.17%;提高采收率幅度比聚合物驱高2.96个百分点的条件下,化学剂费用降低11.4%～19.9%。矿场试验结果还表明,微凝胶驱技术与聚合物驱技术结合使用,可以取得更好的驱油效果。

Microgel flooding technique （low-concentration cross-linked polymer flooding） is one of low-cost and higheffect （ high input-output ratio） enhancing oil recovery techniques. On the basis of indoor studies on this technique, different-size field tests of single-well test injection, single-well flooding, multiple-well groups flooding and so on have systematically caught out in Henan Oilfield. All the performances are quite different from the dynamic characteristics of polymer flooding ： bigger rising degree of injection pressure, much better improved degree of water-absorption cross section, lower produced water concentration, later response time and so forth. 0. 19--0. 37 PV microgel solution （HPAM： 400mg/L, Cr^3＋ ： 60mg/L） prepared by produced oilfield water has injected into Xia＇ ermen No. H2 m and Shuanghe No. 437 Ⅱ 1-2 oil reservoir groups of the pilot, finally results in incremental equivalent oil 85.2--105.3t per ton of polymer, enhanced stage oil recovery 6.01%--7.17% and increased oil recovery degree 2.96% higher than the one of polymer flooding but the chemicals＇ cost has reduced 11.4%--19.9%. The field test results show that the combination of microgel and polymer flooding techniques can obtain much better oil flooded results and furthermore the study thoughts of the above two techniques＇combination have been caught out in the end.