METHOD FOR GAS WELL KILLING Russian patent published in 2013 - IPC E21B43/12 

FIELD: oil and gas industry.

SUBSTANCE: method includes blocking of a perforation interval by means of injection of a blocking liquid and its pushing with a killing fluid to a bottomhole and to a bottomhole area of a bed with simultaneous monitoring of pressure at a well head, gas relief and process settling. At the same time, prior to injection of the blocking fluid, a sand screen is formed by injection of a pulp of quartz sand with fraction of 0.6-1.2 mm in a carrier fluid in two portions with a flow rate of a carrier fluid, the value of which does not exceed the maximum permissible value, defined according to the formula. At the same time the volume of the quartz sand in the first portion of the pulp is calculated in accordance with the formula with further process settling of the well for the time determined according to the formula after injection of the first pulp portion. The volume of the quartz sand in the second pulp portion is taken as equal to the volume of suffosion channels produced in the sand screen. The blocking fluid is a certain composition. The blocking fluid volume is previously calculated according to the formula. Besides, at the moment of completion of blocking fluid pushing, hydrodynamic pressure is determined in a tubing string. Afterwards the process settling of the well is carried out. Further injection of the killing fluid into the well is carried out along the tubing string until it appears at the well head. At the same time the well head pressure is controlled in the annular space of the well by means of gas and blocking fluid relief, providing for pressure at the inlet to the tubing string as permanent and equal to the predetermined hydrodynamic pressure.

EFFECT: improved efficiency of gas well killing.

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