METHOD FOR INJECTION OF TWO-COMPONENT COMPOUND TO FORMATION Russian patent published in 2015 - IPC E21B33/138 

FIELD: oil and gas industry.

SUBSTANCE: method for injection of two-component compound to formation includes running in to isolation interval of cementing string with a packer and sleeve consisting of a housing with end-to-end channel and lateral openings interconnected with a valve unit feeding outside-in. The packer is set above the formation. The first component is injected through cementing string, the second component is injected through annular space and the valve unit into the housing where the second component is mixed up with the first one in end-to-end channel of the housing, then the mixed up two-component compound is injected to the formation. Specific injectivity is defined for formation preliminary, and it should not exceed 2.0 m³/(h/MPa). The sleeve is equipped additionally with a jet pump in end-to-end channel, which is interconnected to the valve unit through lateral openings along perimeter and intermediate chamber that covers the sleeve housing from outside. Thereafter the second component is injected through annular space up to the valve unit flushing the borehole fluid though the valve unit into the sleeve and further to the formation. Thereupon the first component through the cementing string is injected up to the jet pump flushing the borehole fluid to the formation. Thereafter excess pressure is generated in annular space, which is sufficient to half-open the valve unit, and through the cementing string flow of the first component is generated for even and intensive mixing of two components in the jet pump due to availability of the intermediate chamber. At that proportions of components in the two-component compound are controlled by volumes of fluid injection through the cementing string and annular space from the well mouth.

EFFECT: improved efficiency of the formation shutoff; improved quality of two components mixing in the compound, improved accuracy of dosing for the second component flushed from annular space.

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