Influence of the depth of gas-lift gas injection into tubing and its consumptions on the flow rate of a water-cut gas well

Abstract

The features of the development of gas deposits in the water drive and watering of wells are characterized. The sequence of application of various methods of operation of water-cut gas wells is considered, depending on the degree of depletion of the gas reservoir and the water factor. The expediency and conditions for the use of the gas-lift method for the operation of water-cut gas wells have been substantiated. Using the calculation method proposed by the authors, studies of the effect on the flow rate of gas that flows from the reservoir and the bottomhole pressure of the gas-lift gas flow rate and the depth of its injection into the tubing were carried out for the conditions of a model water-cut gas well. It was found that with an increase in the gas-lift gas flow rate, the bottomhole pressure first decreases and reaches a minimum and then increases, while the gas flow rate, on the contrary, first increases, reaching a maximum, and then decreases. With an increase in the depth of gas-lift gas injection into the tubing, the bottomhole pressure decreases, the gas flow rate increases, and the difference between the maximum and minimum values of the gas-lift gas flow rate increases, within which a water-cut gas well can be operated by the gas-lift method. According to the results of statistical processing of the calculated data, it was found that the greatest change in gas flow rate and bottomhole pressure occurs up to the values of the ratio of the depth of gas-lift gas injection into the tubing and the length of the tubing, equal to 0.50-0.55.