通道压裂支撑裂缝影响因素分析

Infleuence factors analysis of proppant fracture in channel fracturing

 许国庆 张士诚 王雷 韩晶玉

 中国石油大学（北京）石油工程教育部重点实验室，北京 102249

 MOE Key Laboratory of Petroleum Engineering, China University of Petroleum, Beijing 102249, China

 为了检测通道压裂所能提供导流能力大小及裂缝的有效性，利用某地层构造的砂岩、页岩进行室内导流能力测试。实验结果表明：通道压裂纤维用量为0.6%比较合适；支撑剂粒径对裂缝的导流能力影响较弱，在相同铺砂浓度下，不同粒径间支撑剂的导流能力差别很小；铺砂浓度对通道压裂导流能力影响较大，大量的支撑剂嵌入对低铺砂浓度导流能力伤害较为明显，高闭合压力下易造成明显的导流能力损失；陶粒、石英砂、覆膜砂3种支撑剂，在相同铺砂浓度下，随着闭合压力的增加，导流能力逐渐下降，覆膜砂的导流能力优于陶粒、石英砂；在相同铺砂条件下，支撑剂在砂岩中的嵌入程度高于页岩，导致其导流能力低于页岩中的导流能力。同时全面分析总结了在通道压裂中，影响支撑剂嵌入的各种因素，从而对优化通道压裂具有一定指导意义。

 In order to learn the conductivity of channel fracturing and its effectiveness, conductivity experiments are done to testify it by using sandstone and shale rock cells. The result shows that mass fraction of fiber in proppant at 0.6% is suitable; the grain size of proppant has little effect on channel fracturing conductivity, under same sand concentration, there is little difference among them; sand concentration has a serious effect on conductivity because serious embedment of proppant for low sand concentration has serious damage to conductivity, under high closure pressure, it may lead to obvious loss in conductivity; for ceramic sands, coated sands and quartz sands, under same concentration their conductivities declines, when the closure pressure goes up and coated sands perform best, ceramic sands take the second place; under same sand conditions, the embedment of proppant in sandstone is more serious than that in shale, which may cause its conductivity lower than that in shale gas. At the same time, we analyze and summarize all the factors that affect conductivity in channel fracturing which has a guiding significance for optimizing the channel fracturing.

10.6056/dkyqt201504029