The influence of desalinization of reservoir rocks on their mechanical and filtration properties using the example of the Chayandinskoye field

Using the Independent Triaxial Loading Test System of the Institute for Problems in Mechanics of the Russian Academy of Sciences (TILTS), rock specimens from the core material of the reservoir of the Chayandinskoye oil and gas condensate field were tested in order to experimentally study the effect of desalinization of reservoir rocks on their deformation, strength and filtration characteristics. It has been shown that desalinization sharply increases the permeability of rocks. At the same time, the deformation and strength properties of the studied rocks change towards softening (with the exception of the angle of internal friction), nevertheless remaining quite high. Experiments on physical modeling of the process of reducing pressure at the bottom of a horizontal well using TILTS showed that a slight decrease in the elastic and strength properties of the reservoir rocks of the Chayandinskoye oil and gas condensate field after their desalinization should not affect the stability of the well walls. The results obtained allow us to draw an important practical conclusion that when operating a field at the stage of salt washing out due to water filtration during operation, one should not expect a significant increase in the risks associated with reservoir destruction and increased sand production.