页岩气压裂用线性胶压裂液性能研究与现场应用

Study on Properties of Linear Gel Fracturing Fluid and Its Field Application for Shale Gas Well

线性胶压裂液是页岩气开采最关键的技术之一。以SRFP-1增稠剂、SRFC-1交联剂、SRCS-1黏土稳定剂和SRCU-1助排剂工业品制备SRFP线性胶压裂液;评价了该压裂液体系的耐温耐剪切性能、降阻性能及破胶性能;测定了破胶液的表面张力及残渣含量。结果表明：SRFP线性胶压裂液在70~100℃条件下具有良好的流变性能;在60~80℃,破胶剂加入量为0.005%~0.05%条件下,2h内即可破胶,破胶液黏度小于5mPa·s,破胶液表面张力小于28mN/m,残渣含量小于100mg/L;最后将SRFP线性胶压裂液成功应用于宁夏某重点页岩气探井,最高砂比为22%,平均砂比为8%,返排液黏度小于5mPa·s。

Preparation of linear gel fracturing fluid is one of the key technologies of shale gas exploitation. SRFP-1 gelling agent, SRFC-1 cross-linker, SRCS-lanti-swelling agent and SRCU-1 cleanup additive were used to prepare SRFP linear gel fracturing fluid. The temperature resisting and shearing resistance, drag reduction and viscosity break performances of SRFP linear gel fracturing fluid were studied. The surface tension of the gel breaking liquid and the content of residue were measured. The results showed that SRFP linear gel fracturing fluid exhibited better temperature resisting and shearing resistance performance under the conditions of 70~100℃. Under the conditions of 60~80℃ 0. 005%~0.05% breaker and 2 h, the viscosity of gel breaking liquid was less than 5 mPa ·s, the surface tension of the gel breaking liquid was less than 28 mN/m, and the residue content of gel breaking liquid was less than 100 mg/L. The SRFP lin- ear gel fracturing fluid was successfully used in one important shale gas well located in Ningxia Province. The highest sand ratio was 22%, the average sand ratio was 8% and the viscosity of flowback fluid was less than 5 mPa·s.