FLOWING WELL KILLING METHOD Russian patent published in 2006 - IPC E21B43/12 C09K8/02 

FIELD: oil and gas industry, particularly flowing well killing for underground repair and overhaul performing.

SUBSTANCE: method involves blocking perforation interval and part of well bottom zone by replacing well fluid with blocking fluid and killing liquid arranged over the blocking one. Free gas is removed from well before blocking fluid delivery to well bottom. Necessary liquid level at well head is provided by well operation stoppage for a certain time, which provides termination of formation fluid degassing in well bore and free gas lifting to well head. Tube space and hole annuity is filled with liquid in several steps along with discharge of gas portions. Gas portion discharge may not result in formation fluid rise inside well bore to level of formation fluid degassing. Density of liquid to be added in tube space and hole annuity provides well filling to head thereof. Well killing liquid comprises industrial magnesium chloride, alkali or alkaline-earth metal hydrate, alkali metal carbonate and pore sealant, for instance cacao-bean pods and fresh water taken in predetermined ratio.

EFFECT: increased efficiency, possibility to kill wells characterized by abnormally high permeability of production bed and high gas factor.

2 cl, 1 ex