Technology for killing gas wells at managed pressure

Abstract

Relevance. The need to solve the problem of developing gas wells after multistage hydraulic fracturing. This problem consists in losses of process fluids during killing gas wells with high permeability by traditional methods, and reducing the achieved productivity of gas deposits. Aim. To develop and justify a method for gentle killing of gas and gas condensate wells after working out in operation mode. Objects. Gas and gas condensate wells after multistage hydraulic fracturing. Methods. Filtration experiment to determine the effect of killing fluid on reservoir permeability; mathematical modeling of gentle killing of a gas well using flexible tubing and equipment for work at controlled pressure; laboratory studies of the mechanical properties of the blocking pack – liquid packer. Results. According to the results of the filtration experiment, the negative effect of the silencing fluid on low-permeable gas layers is justified. The authors developed the technology of gentle killing of gas and gas condensate wells using flexible tubing and equipment for operations at controlled pressure. Laboratory studies were carried out and technological parameters were selected for the second blocking pack – a liquid packer for additional isolation of a gas reservoir. The authors constructed a mathematical model of killing gas wells using the presented technology; a calculation was carried out for the conditions of a gas condensate field in Eastern Siberia. The paper introduces the results of modeling technological operations reflecting the change in the main technological parameters during well killing.