摘要
文、卫油田属复杂断块油田,储层非均质性较严重,层间渗透率变异系数为0.73～0.87。由于断块碎小、难以形成完善注采井网、能量衰减快三大矛盾突出,注水剖面和产液剖面极为不均,严重影响了油田的开发水平。同时,井况恶化,卡封分层酸化受限,而笼统酸化只有少量酸液进入渗透率较低的层位,无法达到均匀布酸的目的,不能有效解除中低渗透层伤害。通过泵入暂堵剂在高、中渗透层形成低渗透滤饼,从而使酸液转向中、低渗透层,充分挖掘笼统酸化波及不充分的低渗透层的潜力,强化差层动用。室内评价与现场实验相结合,为满足中低渗透层酸液分布剖面调整需要,筛选出了颗粒型水溶性暂堵剂。通过完善施工工艺、调整酸液配方、分析污染堵塞原因、合理确定处理半径和暂堵剂类型等措施手段,提高了暂堵酸化的针对性和酸化堵效果。为非均质性严重油藏中低渗透层的注水开发提供了一条有效的工艺途径。现场应用5井次,工艺成功率100%,暂堵有效率87.3%。
Temporary blocking and acidification technology is to form low permeability filter cake in high permeability layer and parts of middle permeability layer by pumping temporary plugging agent, and then the acid will flow to low permeability layer, and thus, the contamination in middle and low permeability zones can be removed effectively, the input profile can be improved greatly and usage of the acid is enhanced. Combined with indoor valuation and the field experiment, the granular water-solubility temporary plugging agent was selected. The breaking time of the plugging agent was more than 16h under the condition of 100℃~120℃,and it could dissolve completely after water injection and the percolation rate recovery of high permeability layer was more than 85%. By perfecting the operation technology, adjusting acid liquor formula, analyzing the cause of plugging, and selecting temporary plugging agent reasonably, the pertinence and effect of temporary blocking and acidizing were improved. It provided an effective technique approach for the water injection exploitation in middle and low permeability zones. Application results of temporary blocking and acidizing technology in 5 wells showed that the success rate was high up to 100%, effective rate of temporary blocking was 87.3% and water injectivity index was increased by 3.7 m3/MPa.
出处
《钻采工艺》
CAS
北大核心
2011年第6期55-57,8-9,共3页
Drilling & Production Technology
关键词
暂堵酸化
吸水剖面
酸化解堵
渗透率
非均质性油藏
暂堵剂
temporary blocking, acidizing, injection profile, broken down, percolation rate, heterogeneity reservoir, temporary plugging agent
