Experimental Study on Novel High Density and High Temperature Tolerant Fracturing Fluid

Abstract

Based on weighted agent sodium chloride, this study introduces a high density and high temperature tolerant fracturing fluid. According to the evaluation of the effect of weighted agent on the performance of base fluid and crosslinked fluid, conclusions can be got as follows. Introduction of weighted agent provides an auxiliary viscosity enhancement of the base fluid to some extent. Meanwhile, the crosslinked time is prolonged and gel breaking becomes more difficult owing to the interference effect of metal ions exerted on the crosslinking process between molecular chains of guar and crosslinker. Moreover, the experiments show that the novel fluid system has a strong tolerance of high temperature and high shearing rate. The viscosity of the fluid system with 15% weighted agent sodium chloride can maintain 160 mPa•s after 120 min shearing at 170 s-1under the temperature of 150 °C. The excellent performance of the fluid system ensures it has a good stimulation effect in the fracturing treatment in the deep and high temperature formation stimulation treatment.