Abstract:
Conventional water-free fracturing fluid can characterized by poor heat-resistance.Under such circumstances,water-free fracturing fluids based on low-carbon chain hydrocarbon pentane,phosphate surfactant (LPEA-1) and viscosity promoter (FS-1) were developed with desirable heat-resistant performances.In the concerned study,the properties of the fracturing fluid Frac-H were evaluated.The viscosity of the fracturing fluids is higher than 50 mPa·s after a continuous shearing of 120 min under temperature 130℃ and a shearing rate of 170 s-1 and it may have maximum viscosity after 180 s.No gel breaker is required during gel breaking processes.In addition,no residue was found in the fluids after gel breaking.The pentane-based Frac-H fracturing fluid may cause slightly higher damage to shale formations than to tight formations,but they are much less than those induced by water-based fracturing fluids.Research results showed that the pentane-based Frac-H fracturing fluid with pentane,phosphate surfactant and viscosity promoter can effectively meet the performance requirements towards frac fluid in unconventional reservoirs fracturing treatment.