RESEARCH AND IMPROVEMENT OF THE QUALITY OF OIL AND GAS WELL KILLING TECHNOLOGY THROUGH THE USE OF VISCOELASTIC COMPOSITIONS

Abstract

Currently, many enterprises of the oil and gas industry are faced with such a problem as a significant decrease in the productivity coefficient of the well after repair work. As a result of such a complication, the process of normalization of the bottom of absorbing wells becomes more difficult, and the period of underground repair increases. The most developing direction in well jamming technology is the use of viscoelastic compositions, since this method eliminates the risk of penetration of the jamming fluid into the collector. Viscoelastic compositions are solutions of crosslinked polymers in the form of elastic gels with high viscosity and high shear stress. The compositions injected into the well limit the penetration of the jamming fluid into the bottom-hole zone of the formation and preserve its reservoir properties. The prepared formulations should take the form of a filling volume and gradually harden over a given time, but not turn into a solid composition.But, despite the high efficiency of using viscoelastic mixtures, this method of jamming has negative sides: premature structuring of the mixture, failure of downhole pumping equipment. The reason for this is the heterogeneous composition of the viscoelastic mixture. The choice of formulations for conducting a complex of laboratory studies implies work to determine the effective type of blocking composition and the choice of reagent brands.To clarify the conditions for the effective use of viscoelastic formulations and cooking technologies, an analysis of domestic and foreign experience in their application was carried out.During the research, optimal formulations of viscoelastic mixtures were selected that meet the requirements of well jamming technology at the «X» field. These samples are capable of forming strong cross-linked plugs that do not change the strength characteristics of the structure over time. To remove the composition of the silencing fluid from the borehole, the technology of dispersing viscoelastic mixtures using a hydroperite destructor was tested. After the introduction of the destructor, the ionic bonds of the composition are destroyed, which leads to a decrease in viscosity to minimum values and the possibility of its complete removal from the formation.