摘要
针对我国煤储层普遍具有"低压"、临储比小等特点,提出利用液氮伴注辅助水力压裂技术改造煤储层。系统分析了利用该项技术提高煤储层临界解吸压力的机理:当氮气分子进入到煤储层中,会与甲烷分子共同占据孔隙空间,由此可以为储层提供额外能量,同时能够为煤储层中甲烷分子提供分压,提高其临界解吸压力,促使气体能够更容易、更快地解吸出来。现场试验表明:利用液氮伴注辅助水力压裂技术能够有效提高煤储层的临界解吸压力,能够缩短排采初期的排水降压时间,达到提前产气的效果。
In view of the characteristics of ＂low pressure＂ and Pro storage ratio in coalbed methanereservoirs of China, it is proposed to reconstruct the coal reservoirs by injecting liquid nitrogen with thetechnology of hydraulic fracturing. The mechanism of using this teehnology that when the nitrogenmolecules enter the coal reservoir, they will occupy the space, it can provide extra energy for reservoir,and it also can provide partial pressure for methane molecules in coal reservoirs, and it also can providepartial pressure for methane molecules in coal reservoirs, and enhance the critical desorption pressure,so that the gas can be desorbed easily and quickly. The field test shows that using this technology canprovide the critical desorption pressure, it also can shorten the pumping time, to achieve the gasproduction in advance.
出处
《煤炭技术》
CAS
2018年第2期201-203,共3页
Coal Technology
基金
"十三五"国家科技重大专项课题任务(2016ZX05045002-007)
中煤科工集团西安研究院有限公司科技创新基金项目(2017XAYMS19)
关键词
液氯伴注
临界解吸压力
水力压裂
liquid nitrogen with injection
critical desorption pressure
hydraulic fracturing
