Control mechanism of pressure drop rate on coalbed methane productivity by using production data and physical simulation technology

作者：Heyao Miao, Veerle Vandeginste, Junjian Zhang, Shangbin Chen, Xiangchun Chang, Yi Du, Yang Wang, Chongtao Wei, Jinhui Luo, Fangkai Quan, Xiaoli Shen · 发表于：Fuel · 年份：2025 · DOI：10.1016/j.fuel.2025.137060 · 被引用次数：24 · 研究领域：Coal Properties and Utilization、Methane Hydrates and Related Phenomena、Hydrocarbon exploration and reservoir analysis

When determining the location of Coalbed Methane (CBM) wells, pressure variation is a key factor affecting CBM productivity. Understanding the relationship between reservoir pressure and gas production has become a central challenge in CBM development. In this study, drainage data from CBM wells located in a specific area on the eastern margin of the Ordos Basin were analysed to investigate the influence of geological parameters (e.g. coal seam thickness, burial depth) on productivity across different CBM well types. Subsequently, the effect of pressure drop rate on CBM production dynamics was studied. To further explore this relationship, low-field nuclear magnetic resonance (NMR) experiments were conducted to simulate stepwise depressurization and methane desorption. These experiments addressed the impact of pressure drop rate on methane desorption from both primary and fractured coal structures. A numerical simulation model was then developed to evaluate CBM production performance under varying pressure drop rate constraints. This integrated approach considered key factors such as reservoir pressure and gas content to systematically assess the influence of pressure drop rate on CBM productivity. The main findings are as follows: 1) Pressure-production relationship: An exponential relationship was observed between the pressure decline curves of vertical and horizontal wells. The pressure drop stage corresponds to the stages of increasing and stable gas production. A higher ...