加砂压裂用滑溜水返排液重复利用技术

Reuse technology of slick water fracturing flowback fluid

非常规储层体积压裂施工液体用量大,返排液多,返排液中含有各种地层离子、残余添加剂、悬浮物等,无害化处理难度较大。介绍了国外体积压裂返排液的处理方式,并结合四川盆地的特点,形成了适合于四川盆地非常规储层体积压裂返排液回收利用处理流程。室内研究表明,体积压裂返排液中的残余添加剂浓度较低,具有一定的矿化度,采用回收利用处理流程进行处理后,其摩阻与清水配制的体积压裂液相当。现场应用也进一步表明,体积压裂返排液处理后配制的液体摩阻性能与清水配制的相当。现场获得了良好的储层改造效果,节约了配液用水,减少了废弃物排放,实现了节能减排。

Volume-fracturing in unconventional reservoirs needs massive fluid and brings plen- ty of flow-back fluid which contains varied ions, residual additives, suspending matters and so on,so harmless disposal has great difficulties. This paper introduced the ways of disposal flow back fluid from volume-fracturing, and combined the actual circumstance of unconventional gas well in Sichuan. We formed the disposal flow-back fluid process. Laboratory study showed that concentration of residual additives were low in flow-back fluid, but had a certain amount of total dissolved salts, the drag friction of the treated flow-back fluid was the same as the fracturing flu- id produced by the freshwater. It also came to the same conclusion in field trial, which gained ef ficient reservoir reformation, saved freshwater, reduced drainage of waste water, and achieved energy conservation and emission reduction.