Research on clean fracturing fluid and its application to shallow low-temperature oil reservoir

According to the basic requirements of low-temperature and low-permeability reservoir in the southern steep slope of Henan Oilfield on the fracturing fluid, IBF anionic viscoelastic surfactant is selected as the master agent for making clean fracturing fluid through indoor experiments. The throat size of the anionic viscoelastic surfactant to the sandstones can be reduced and the problem of rock surface wettability reversal can be solved completely, by using the anionic viscoelastic surfactant. So the no-damage performance of the fracturing fluid is fulfilled. Meanwhile, the fracturing fluid features in low viscosity and high elasticity, low friction, strong sand-carrying capability, no use of gel breaker, and favorable surface activity. The one-off cross-linked fracturing technology with variable concentrations is used, and the cost is saved a lot. It has been used in 16 wells, with the success rate and efficiency reaching 100%. Accumulatively the output of oil is increased by 9,373 tons. The application of the technology provides solid technological basis for the development of the block.