摘要
致密砂岩储层天然气投产一般需要采取水力压裂等增产措施。由于天然气在产出过程中需要通过致密基块—天然裂缝—水力裂缝等多尺度介质,故而在渗流中存在多尺度效应,需要经过一系列串联耦合过程,其中任何一个环节都可能影响天然气的高效产出。为此,通过自行设计"串、并联"气体传质实验方法及装置,探讨了裂缝宽度、裂缝—基块的配置关系等对致密砂岩气体传质效率的影响。"并联"气体传质实验表明,裂缝宽度是影响气体传质效率的关键参数,相同数量级裂缝宽度的天然裂缝传质效率高于人工裂缝。裂缝—基块岩样"串联"气体传质实验表明,裂缝—基块多尺度配置关系中,裂缝—基块—裂缝的配置关系最优,气体传质效率最高。结论认为,合理开发致密砂岩气藏需贯彻"储层保护与改造并举"的方针,实现致密基块—天然裂缝—水力裂缝的合理配置,才能有效开发致密砂岩气藏。
Stimulation measures like hydraulic fracturing are usually required for high yields in tight sand gas reservoirs.During its output,natural gas has to get across a multi-scale medium,i.e.,tight matrix,natural fractures,and hydraulic fractures,which results in a multi-scale effect during the seepage.Moreover,natural gas has to go through a process of couplings reaction in series,during which a high yield will be possibly influenced by any segment.Therefore,by use of self-designed methods and laboratory equipments for gas mass-transfer experiments of series and parallel connections,the influences of fracture width and the configuration between matrix and fracture are discussed on the gas mass-transfer efficiency in tight sand gas reservoirs.In the parallel connection case,the experiments show that fracture width is the key parameter influencing the gas transfer efficiency;while with fracture width of the same order of magnitude,the transfer efficiency of natural fractures is higher than that of artificial fractures.In the series connection case of matrix and fracture,the experiments show that the fracture-matrix-fracture is the best among the multi-scale configurations,and its corresponding gas transfer efficiency is the highest.From an integrated study,we suggest that the strategy of both reservoir transformation and protection should be taken to achieve reasonable configuration of tight matrix,natural fractures,and hydraulic fractures,thus leading to the efficient development of tight sandstone gas reservoirs.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2010年第10期39-41,共3页
Natural Gas Industry
基金
博士后基金(编号:20090451422)
国家科技重大专项(编号:2008ZX05022-004-04HZ
2008ZX05045-003-01)
四川省杰出青年学科带头人培养基金项目(07ZQ026-113)
关键词
致密砂岩
储集层
压裂
裂缝(岩石)
多尺度
传质
配置关系
tight sandstone,reservoir,fracturing,fracture(rock),multi-scale,mass transfer,configuration relations
