Optimal selection of drainage gas production process measures for tight gas wells based on improved combination weight- technique for order preference by similarity to an ideal solution method

Liquid loading remains a critical challenge in the late-life production of gas wells, often resulting in reduced output and operational inefficiencies. To address the limitations of conventional deliquification technology selection methods—typically constrained by subjective bias or reliance on single-indicator weighting—this study proposes an improved multi-criteria decision-making model. The proposed framework integrates the Critic method, entropy weight method, and coefficient of variation method, further refined through a Lagrangian optimization function to achieve balanced and objective weight allocation. By systematically incorporating diverse technical and economic indicators—such as gas production, process cost, operating cycle, and investment payback period—the model enables comprehensive and data-driven process evaluation. The model was validated using real-world data from three representative gas wells: Xushen 8, Tiandong 82, and X1. Results demonstrate that the proposed method successfully identified optimal drainage solutions consistent with field applications: electric submersible pump (ESP) for Xushen 8, foam lift for Tiandong 82, and optimized tubing configuration for X1. Compared with traditional methods such as Analytic Hierarchy Process (AHP) and single-objective weighting, the proposed model offers enhanced differentiation, robustness, and alignment with operational outcomes.