缩膨剂HDS-01及其缩膨降压增注技术

研制了一种不仅能防止粘土水化膨胀 ,还能使已水化膨胀粘土颗粒体积收缩的阳离子聚合物即缩膨剂HDS 0 1,用于中原卫城、马寨油田水敏储层注水井的减压增注处理。介绍了该剂的缩膨机理。以现用防膨剂SSN 13(一种聚季铵盐 )为对比剂 ,考察了HDS 0 1的应用性能 :HDS 0 1和SSN 13的缩膨率分别为 81.5 %～ 86 .2 %和 17.2 %～ 18.5 % ;防膨率分别为 84 .5 %～ 86 .2 %和 81.5 %～ 83.2 % ;储层水敏岩心在HDS 0 1和SSN 13溶液中的失重率分别为 <7%和 >6 0 % ;充填砂柱经HDS 0 1和SSN 13溶液处理后 ,冲刷出的微粒量分别为空白实验值的 1.2 5 %～ 2 .6 0 %和 96 .4 %～ 12 1.9% ,最终渗透率分别为初始值的 98.6 %～ 118%和 12 %～ 5 2 % ;常规酸化后岩心注水压力迅速回升到原值 ,缩膨处理后则稳定下降 ,长时间内回升趋势很小。现场使用的HDS 0 1溶液浓度 5 %～ 15 % ,处理半径 1.5～ 2 .0m。介绍了在 38口注水井进行HDS 0 1缩膨处理的结果 :注水压力下降 ,注水量上升 ,有效期超过 132天 ,许多对应油井增产。图 4表 3。

Stimulation of Water Injection Wells by Using Swelled Clay Shrinkage Agent HDS-01

A cationic polymer capable of shrinking swelled clay in volume as well as preventing clay from hydrating and swelling, swelled clay shrinkage agent HDS-01, is developed for treating/stimulating water injection wells in water sensible reservoirs at Weicheng and Mazhai oil fields of Zhongyuan. HDS-01 has been evaluated in laboratory for performance properties in comparison with a clay stabilizer presently used, SSN-13 (quartenary ammonium salt polymer). For HDS-01 and SSN-13, the volume shrinkage rate of swelled bentonite is in range 81.5-86.2% and 17.2-18.5%; the swelling reduction rate of bentonite - 84.5-86.2% and 81.5-83.2%; the weight loss of core sand after immersion in test solution is of <7% and >60%; the quantity of the fine particles washed out of HDS-01 and SSN-13 treated sand packs is of 1.25-2.60% and 96.4-121.9% of the blank experimental data and the ultimate permeability of these treated sand packs is of 98.6-118% and 12-52% of the initial values, respectively; the water injection pressure in a reservoir core increases fast after acidizing but decreases steadly in long time with little tendency to raising after HDS-01 treating. The working solution concentration of HDS-01 used in field is in range 5-15% and the shrinkage treating radius - 1.5-2.0 m. The results of shrinkage/stimulation in 38 injection wells are presented: decrease in water injection pressure and increase in volume of water injected observed in 132 days in average and enhancement in oil productivily appeared in a lot of connected production wells.