Laboratory Research on Oil Base Fracturing Fluid in Low-permeability Reservoirs in Haungchang Area of Jianghan Oilfield

Large permeability variation coefficients, low porosity, low permeability and strong water lock exist in Block Huangchang in Jianghan Oilfield. Experiments were done to optimize the oil base fracturing fluids, in which the dewatered crude from Huangchang oilfield was used as the base fluid, LHPG02 (a phosphate) was used as the gelling agent, sodium metaaluminate as the cross-linking agent, and anhydrous sodium acetate as the gel breaker. The oil base fracturing fluid formulation was as follows: JHYY+-(1. 0%-1. 5%) LHPG02-K0. 09%-0. 2%) NaAlO2 + (0. 07%-0. 1%) NaAc. Core tests showed that the use of the new fracturing fluid gave birth to a minimum permeability recover rate of 78. 95%, with an average value of 86. 13%.