抗高温硼交联压裂液体系研究

Research of Borate Crosslinked Fracturing Fluids at High Temperature

常规体系压裂液在高温下受热、剪切黏度降低过快,无法满足超深井压裂改造的要求,通过对配方主剂研究及体系性能的测试,形成了新型高温压裂液体系。实验表明,该体系耐温性能、破胶性能、降滤失性能均优于常规压裂液体系,在170℃高温环境中性能稳定,配伍性良好,在显著提高耐温、抗剪切性能的同时,没有增大对地层渗透率的伤害,使压裂工艺应用范围得到显著扩大。现场应用中最深施工井段达4899.0m,最高井温达169.5℃;该高温压裂液体系在辽河油田的应用,井深超过4000m的压裂井累计达23井次,最高加砂量为100m3,最大用液量为763.8m3,成功率达100%,有效验证了该体系的高温稳定性及可靠性。该体系未对深层油藏及气藏不同特性进行区分,下一步应开发出更有针对性的油气储藏压裂液配方。

Viscosity of regular fracturing fluid system decreased too fast by heat and shear at high temperature to meet the requirement of fracturing for the ultra-deep wells.Based on the research of key agent of the formula and performance tests of the system,a new type of high-temperature fracturing fluid system was developed.Experiments show that this system has better performances on temperature tolerance ,viscosity break property and fluid loss property than the regular fracturing fluid system.It has good stability ,good compatibility and lower damage for the layers at 170℃.Its fracturing technology application is significantly expanded.The depth of the deepest well in field application reached 4899.0m,and the temperature of the deepest well reached 169.5℃ .It is applied in Liaohe oilfield with 100% of successful rate.The fracturing wells with the depth of more than 4000 meters are implemented at 23 fracturing well-times with 100m^3 of the maximum gravel input and 763.8m^3 of the maximum fluid input.The field application effectively verified high-temperature stability and reliability of this system.Deep oil and gas reservoirs with various properties should have various formulas of the fracturing fluid.