摘要
致密油藏水平井(井周/井间)裂缝窜流导致开发中、后期能量补充不"均衡"甚至无法补充。通过实验设计研发了基于纳米纤维(NCF)的高稳泡沫体系,并系统研究了高稳泡沫的宏观/微观性质;通过实验室构建的裂缝模型,研究了高稳泡沫在裂缝中的生成和运移规律。研究结果表明,起泡液在质量分数为4.2%的盐水中高度分散,与地层水配伍性好,NCF可以有效抑制泡沫液膜脱水,减缓泡沫失稳过程,泡沫半衰期提高4.5倍;高稳泡沫可以在裂缝中快速生成然后运移至裂缝深部,从而降低裂缝的渗流能力,防止气窜,气液比为2∶1的高稳泡沫产生的流动阻力最大;裂缝开度越小,泡沫生成的速度越快,流动阻力越高,产生高渗流阻力的区域越宽;高稳泡沫在裂缝中的流动阻力和裂缝渗透率呈现良好的线性关系。基于NCF高稳泡沫在裂缝中的流动特征,进一步构建了泡沫流动阻力与气液线速度关系图版。
Fracture crossflow in horizontal wells(around well/cross-well)of tight oil reservoirs leads to the imbalance of energy complement in the middle and late stages of exploitation,which is even impossible to be supplemented. A nanofiber(NCF)-based high-stability foam system was designed and developed in the experiment,and the macro/micro properties of the high-stability foam were systematically studied. Using the fracture model constructed in the laboratory,a study was performed on the formation and migration laws of high-stability foam in the fracture. The foaming solution is highly dispersed in 4.2% salt water and has good compatibility with formation water. NCF can effectively inhibit the dehydration of foam films,slow down the foam instability process,and increase the foam half-life by 4.5 times. High-stability foam can be formed rapidly in fractures and rapidly migrates to the deep parts of fractures,thereby reducing the percolation ability of fractures and preventing gas channeling. The high-stability foam with the gas-liquid ratio of 2∶1 produces the largest flow resistance. The smaller the fracture opening,the faster the foam generation speed;the higher the flow resistance,the wider the area with high percolation resistance. The flow resistance of high-stability foam in fractures and the fracture permeability show a good linear relationship. Based on the flow characteristics of NCF high-stability foam in fractures,this study establishes a chart of the relationship between foam flow resistance and gas-liquid line velocity.
作者
魏兵
陈神根
赵金洲
蒲万芬
魏发林
相华
Kadet Valeriy
Wei Bing;Chen Shengen;Zhao Jinzhou;Pu Wanfen;Wei Falin;Xiang Hua;Kadet Valeriy(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Sichuan Chengdu 610500,China;PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083;Gubkin Russian State University of Oil and Gas,Moscow 119991,Russia)
出处
《石油学报》
EI
CAS
CSCD
北大核心
2020年第9期1135-1145,共11页
Acta Petrolei Sinica
基金
国家重点基础发展计划(973)项目“陆相致密油高效开发基础研究”(2015CB250900)
国家自然科学基金面上项目“基于纤丝纳米材料(CNF)高稳泡沫驱体系的构筑及液膜夹断-分离行为研究”(No.51974265)资助。
关键词
致密油藏
裂缝控制
高稳泡沫
泡沫生成运移
防止气窜
tight reservoir
fracture control
high-stability foam
foam formation and migration
prevention of gas channeling
