摘要
水平井分段压裂技术是页岩气开发的关键技术,其方案设计需要对缝网几何参数及导流能力进行优化.目前,借用产能预测模型优化缝网参数的过程较为复杂且忽略了自支撑裂缝对缝网导流能力的影响.根据水电相似原理,将压裂后的复杂缝网细分为支撑裂缝以及自支撑裂缝,提出了等效裂缝的概念,并得出了基于不同裂缝形态的复杂缝网导流能力优化模型,确定了支撑裂缝与自支撑裂缝导流能力之间的关系.结合四川盆地龙马溪组Y1井储层及流体参数,进行水平井分段压裂设计,优化出30/50目与40/70目陶粒的最佳铺砂浓度分别为3kg/m^2和5kg/m^2,70/140目支撑剂无法满足导流能力需求,自支撑裂缝能够满足导流能力需求.结合Meyer模拟得出Y1井30/50目的砂比为2.5%~3%,40/70目砂比为3.5%~4%,有效地减少了支撑剂量,并取得良好的经济产能,值得推广应用.
The staged fracturing technology of horizontal wells is the key technology of shale gas development,and its design needs to optimize the geometry parameters and conductivity of complex network fractures.At present,the process of using productivity prediction model to optimize the parameters of network fractures is more complex and ignores the influence of self-propped fractures on the conductivity of network fractures.According to water and electricity resembling principle,complex network fractures are assumed to consist of propped fractures and self-propped fractures,and the concept of equivalent fracture is proposed.The model for conductivity optimization of complex network fractures based on different kinds of fracture morphology is presented and relationship between conductivity of propped fractures and selfpropped fractures is showed in the research.Combining reservoir and fluid parameters of Well Y1,the fracturing design of horizontal wells is carried out.The optimum sand concentration of proppant of 30/50 mesh and 40/70 mesh is 3 kg/m2 and 5 kg/m2 respectively,the proppant of 70/140 mesh cannot meets conductivity demands,but the conductivity of self-propped fractures meets production demands.The simulation results show that the sand ratio of Well Y1 30/50 mesh is 2.5%-3%,40/70 mesh is 3.5%-4%through Meyer,which effectively reduces the mass of proppant and achieves good economic productivity.It is worth popularizing and applying.
作者
张晗
Zhang Han(Sinopec Chongqing Fuling Shale Gas Exploration and Development Co.Ltd.,Chongqing 408014)
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2019年第7期955-962,共8页
Natural Gas Geoscience
基金
国家科技重大专项“涪陵页岩气开发示范工程”(编号:2016ZX05060)资助
关键词
页岩储层
复杂缝网
自支撑裂缝
水电相似原理
加砂规模
Shale reservoirs
Complex network of fracture
Self-propped fractures
Water and electricity similitude principle
Proppant scale
