油溶性暂堵剂YDJ-1的制备及性能评价

随着油田注水开采的日益增加,储层非均质性增加、综合含水上升,严重制约着原油产量。堵水酸化作业能有效封堵高渗透层,提高低渗透层的可动用储量,使酸液均匀分布在地层,有效缓解层间矛盾。通过优选堵水不堵油的材料,制备得到具有选择性封堵的YDJ-1油溶性暂堵剂,其配方为:70%C9石油树脂+15%改性沥青+7%黄原胶+8%纳米纤维。考察了YDJ-1的溶解能力,并评价了YDJ-1在不同渗透率岩心中的阻力系数、突破压力梯度以及封堵率。结果表明,YDJ-1油溶性暂堵剂在原油中的溶解率在98%以上,对岩心堵水率在95%以上,封堵层的突破压力梯度最大能够达到50 MPa/m以上,具有良好的注入性、封堵性和选择性。

Preparation and Performance Evaluation of Oil-soluble Plugging Agent YDJ-1

With the increasing of water flooding in oilfields,the increase of reservoir heterogeneity and comprehensive water cut seriously restrict the production of crude oil.Water shutoff acidification can effectively plug the high permeability layer,improve the available reserves of the low permeability layer,make the acid evenly distributed in the formation,alleviate the contradiction between layers.The oil-soluble plugging agent YDJ-1 with selective plugging was prepared by optimizing water-plugging and oil-free materials,the formula was 70%C9 petroleum resin+15%modified asphalt+7%xanthan gum+8%nanofibers.The solubility of YDJ-1 was investigated,and the resistance coefficient,breakthrough pressure gradient and plugging ratio of YDJ-1 in cores with different permeability were evaluated.The test results showed that the dissolution rate of YDJ-1 was over 98%in crude oil,the water plugging rate was over 95%in core,and breakthrough pressure gradient of plugging layer could reach up to more than 50 MPa/m,which indicated that the oil-soluble plugging agent YDJ-1 had a good injectivity and plugging and selectivity performance.