The article considers the peculiarities of well killing complicated by high risks of gas breakthrough. The main causes of this phenomenon are identified, including the mismatch of killing technology to the considered conditions, high risks of absorption of killing fluids and gas breakthrough in the already killed well. The technologies used in field practice for killing wells with high gas factor are described: traditional killing technologies with various water-based and hydrocarbon-based fluids; the use of water rims to push gas from the well into the formation and the use of blocking killing compositions. The efficiency of the technology was evaluated by the share of wells killed at the first attempt. The most effective technology is the use of viscous fluids for killing wells, the least effective is the injection of water rim to push gas into the formation without blocking the bottomhole formation zone. The use of high-volume water rims for gas displacement from the gas cap is possible in conditions of low-temperature terrigenous reservoir and normal reservoir pressure. The use of high-viscosity blocking compositions to block gas breakthrough is 1,3-1,5 times more effective than suspension blocking compositions. Ways of increasing the efficiency of technologies are offered. Recommendations on selection of volumes of water rims and blocking compositions for effective killing of wells with high gas factors of produced products are developed. The final choice of technology should be based on the analysis of field information and a set of laboratory studies and field tests of the selected reagents.
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