Diverting acid is an acid system that contains no solid particles or polymers and is mainly composed of viscoelastic surfactants. Under fresh acid conditions, diverting acid has low viscosity, which helps reduce the frictional resistance of the acid and makes it suitable for high-displacement pumping. As the diverting acid reacts with the carbonate rock in high-permeability zones, the acid concentration decreases continuously, and a large amount of MgCl₂ and CaCl₂ are generated. This reduces the electrostatic repulsion between molecules, forming a gel system with a three-dimensional network structure, and the acid viscosity increases rapidly. Thereby, it selectively plugs the high-permeability zones, forces the acid to flow into low-permeability zones, and achieves the purpose of self-diversion.
During flowback, the gel comes into contact with crude oil and other hydrocarbon substances. The hydrocarbons react with the gel system, destroying the network micellar structure and dispersing it into spherical structures, leading to automatic gel breaking of the diverting acid. At the same time, the flowback fluid contains a large amount of water. Through the dilution effect of water, the concentration of micelles in the diverting acid is also reduced, assisting in gel breaking. After rapid gel breaking, the diverting acid reduces the secondary damage to the reservoir.
The diverting acid system independently developed by our company has recently achieved successful application in the Middle East. At a concentration of 20% HCl and with 4% diverting agent, this system exhibits a peak viscosity of over 1000 mPas, a gel-breaking viscosity of less than 5 mPas, and a corrosion rate of less than 7 g/(m²·h). It has been highly praised by customers. If you are interested in this diverting acid system, please feel free to contact us at any time.
Post time:
Sep-02-2025
