异常高温胍胶压裂液体系研制与应用

目前国内常规的压裂液体系仅适用温度150℃以下的地层。室内对影响超高温压裂液性能的主要添加剂——稠化剂和交联剂进行了改性,通过严格控制反应条件,得到低残渣、高黏度的超高温胍胶稠化剂GHPG和超高温延迟交联剂BA1-21,研制出耐温190℃以上的超高温压裂液体系。对超高温改性胍胶的性能进行了评价,对超高温压裂液体系交联剂延迟交联性能、耐温耐剪切性能进行了评价。在ZG63井实施压裂改造8d后,压裂液返排率74.9%,平均产气6000m3/d,初步达到了改造储层并认识储层的效果。该技术对国内深层超高温储层压裂具有一定指导意义。

Research and application of gum/borate gelling fracturing fluid system for abnormal high temperature use

Proper fracturing fluid system is critical to successful deep well (more than 5000m deep) fracturing with abnormal high temperature (higher than 180 ℃). However, conventional fracturing fluid systems now used in China only adapt to the strata with temperature lower than 150 ℃. Lab experiment is conducted to modify two major additives that affect the property of ultra-high temperature fracturing fluid---thickener and crosslinker. By strictly controlling the reaction conditions, GHPG gum/borate gelling thickner with low residue and high viscosity for ultra-high temperature use and BA1-21 delayed crosslinker for ultra-high temperature use are obtained, and a fracturing fluid system resistant to the temperature higher than 190 ℃ is developed successfully. The performance of modified gum/borate gell for ultra-high temperature use is evaluated, the delayed crosslinking performance and heat/shearing resistance of crosslinker of the fracturing fluid system for ultra-high temperature use is also evaluated. Eight days after fracturing and modification in ZG63 well, flow back rate of fracturing fluid attains to 74.9%, with the average being 6000 m3. The reservoir is modified and recognized. This new breakthrough is valuable for deep reservoir fracturing with ultra-high temperature in China.