Incorporating Sustainable Design into a Single Well Gas Lift Optimization
Abstract
Gas lift is a method to increase oil production from a well using injected gas to lower the
density of fluids flowing to the surface. This method is commonly used because of its effectiveness, reliability, and flexibility over a wide range of operating conditions. The gas lift process can be optimized to maximize production by controlling the rate and pressure of injected gas. Past research has focused on optimizing the gas lift operation at a single well or for many wells in the same field. Previous work has sought to optimize well production without integrating methods of sustainable design.
In this study, a well was simulated before and after gas lift was implemented to investigate the
impact of the technology. The operation of the well was assumed to take place over a sufficiently
short period of time such that reservoir properties and reservoir fluid composition remain constant. Production from the well was related to the bottomhole flowing pressure via an inflow performance relationship using both Darcy and Vogel models. Process simulation software (ProMax) was used to evaluate fluid properties at various conditions and to model the operation of common process units such as heat exchangers, compressors, and separators.
This study seeks to include a sustainability analysis into the design of a gas lift project. Including
metrics of sustainability will quantify the tradeoffs between economics and emissions when
adding gas lift to a production well. This work builds on previous work for predicting well performance, with an additional environmental consideration for evaluating project viability. A method for incorporating sustainable design is necessary for decision makers who seek to boost profitability while minimizing environmental impact.
The results of this study indicate the gas lift project would increase the profitability of the well
operation and meet a common acceptable threshold for project ROI. However, if decision makers
account for measures of sustainability, the project would not be profitable but costly. The conflicting directions of the economic and sustainability metrics demonstrate the need for incorporating sustainable design into project selection.
Citation
Trettin, David Joseph (2020). Incorporating Sustainable Design into a Single Well Gas Lift Optimization. Master's thesis, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /192390.