Dynamic simulation and application of continuous tubing gas lift in offshore gas fields

Abstract

Liquid loading is a common issue in offshore gas wells, which often leads to well shutdown and significantly impacts the overall recovery efficiency of gas fields. As a primary deliquification method in offshore operations, coiled tubing gas lift is widely applied in the field. However, there is currently no mature dynamic simulator available for this process. In this study, a dynamic inflow model that couples real-time reservoir changes was developed. The coiled tubing gas lift process was divided into three distinct stages, and corresponding models were established for each stage. The LU decomposition method and Euler equations were employed to solve the system, and a simulation program was developed accordingly. The program was used to calculate and analyze the dynamic variations in parameters such as internal pressure of the coiled tubing, gas density, slug flow velocity, and gas injection rate. This work realizes the dynamic simulation of coiled tubing gas lift and provides a theoretical reference for the optimization of deliquification parameters in offshore gas fields.