可逆交联低伤害聚合物压裂液研究与现场应用

Reversible cross-linking polymer fracturing fluid with low damage property and its field application

以SRFP-1增稠剂、SRFC-1交联剂、SRCS-1黏土稳定剂和SRCU-1助排剂工业品为研究对象，以现场配液用水配制SRFP压裂液。评价了SRFP压裂液的耐温耐剪切性能、静态滤失性能、破胶性能及压裂液滤液对岩心的伤害性能；测定了破胶液的表面张力及残渣含量。结果表明：SRFP压裂液在100℃和120℃条件下具有良好的流变性能；初滤失量为3．29×10^-2m3／m2，滤失系数为1．71×10^-4m／min0.5，滤失速率为6．53×10^-4m／min；压裂液滤液对岩心基质伤害率为14．6％；在60～90℃，破胶剂质量分数为0．005～0．04％条件下，2h即可破胶，破胶液黏度小于5mPa.s,破胶液表面张力小于28mN／m，破胶液残渣小于100mg／L；最后将SRFP压裂液成功应用于2口低渗透致密薄互储层压裂作业，最高产油量分别为5．2m3／d和9．7m3／d。

Reversible cross-linking polymer fracturing fluid with low damage property is one of hot research issues at home and abroad. The fracturing fluid is formulated by using SRFP-1 as thickening agent, SRFC-1 as cross-linker, SRCS-1 as clay stabilizer and SRCU-1 as cleanup additive. The temperature and shearing resistance performance, stability filtration property, viscosity break performance of the obtained fracturing fluid are evaluated. The effect of fracturing fluid on permeability damage of core is also studied. The surface tension of gel breaking liquid and the content of residue are measured. The results show that the resultant fracturing fluid has better temperature and shearing resistance performance under the conditions of 100℃ and 120℃. The filtration loss, filtration coefficient and filtration rate are 3.29 × 10^-2 m3/ m2, 1.71× 10 ^-4 m/min0. 5 and 6. 53 × 10 ^-4 m/min, respectively. The permeability damage rate of core matrix caused by fracturing fluid is 14. 6%. The gel can be broken with 0. 005% - 0.04% of gel breaking agent under 60 - 90℃ for 2 hours. The viscosity of gel breaking liquid is less than 5 mPa. s. The surface tension of gel breaking liquid is less than 28 mN/m and the residue content of gel breaking liquid is less than 100 mg/L. At last, the fracturing fluid is successfully used in fracturing two wells with low permeability and thin interbedded reservoir. Their highest oil production is 5.2 m3/ d and 9. 7 m3/d,respectively. Key words： reversible cross-linking polymer fracturing fluid; rheological property; stability filtration property; gel breaking performance; field application