深部气藏CO_2泡沫压裂工艺技术

APPLICATION OF CO_2 FOAM FRACTURING TECHNOLOGY IN DEEP GAS RESERVOIRS

泡沫压裂工艺技术是低压、低渗、水敏性地层增产增注以及完井投产的重要保障,国外在泡沫压裂(特别是在CO2泡沫压裂)的室内研究、设计以及施工技术、返排技术和压裂效果的现场评价等方面均已比较成熟。由于CO2的特殊性质,其在压裂改造技术中所占的份额将越来越大,在深井压裂改造中亦是如此。我国有许多低压、低渗、水敏性地层以及投产多年的老井需要进行压裂改造。为此,系统地介绍了CO2的基本性质、CO2泡沫压裂的增产机理及CO2泡沫压裂工艺技术,并对中原油田深部气藏的现场施工结果进行了详细地分析,所采用的CO2泡沫压裂较普通的压裂改造效果更好,可作为低渗透气藏开发的一种有效措施。

The foam fracturing technology is an important procedure for enhancing the hydrocarbon recovery from low-pressure,low-permeability and water sensitive formations.And its lab research,design,application,and effect analysis have already become matured in many countries.The application of CO2,due to its special properties,in fracturing technologies is becoming more and more popular,especially in deep wells.In China,there are many low-pressure,low-permeability and water sensitive reservoirs,and as well,many old wells,requiring fracturing.Therefore,this paper introduced in detail about CO2's basic properties,EOR mechanisms,and foam fracturing technology.In addition,this paper analyzed its field application in deep gas reservoirs of the Zhongyuan oilfield,suggesting its great potential for low-permeability gas reservoir development.