Phase Behavior of Fluid Composition in Coalbed Methane Wells Pre- and Post-Workover: An Examination of the Panzhuang Block, Qinshui Basin, Shanxi, China
Year: 2024
Type: article
Abstract: Workover operations significantly impact the service life and gas production capacity of coalbed methane (CBM) wells and are crucial for optimizing resource exploitation. To investigate workover operations’ impact on coal seam reservoirs, the authors designed a series of experiments and obtained the following results: (1) The workover operation induced a phase transition in the solid-liquid composition produced by the CBM well, indicating changes in the coal reservoir’s internal structure. (2) During the stable production stage before and after the workover, the proportion of Na+, Cl−, Ca2+, and Total Dissolved Solids (TDS) in the water samples showed a downward trend as a whole, while the HCO3−; after the workover, the Na+, Cl−, Ca2+, and TDS all increased suddenly, while the HCO3− decreased. (3) While inorganic minerals predominated in the precipitation material during the stable production stage pre-workover, their proportion decreased post-workover, with a noticeable shift in their qualitative composition. (4) It is an indisputable fact that workover operations cause physical and chemical damage to coal seam reservoirs. During workover operation, how to avoid damage and conduct benign reconstruction to the reservoir will be the direction of our future efforts. The experimental results provide valuable insights that can guide the optimization of CBM workover operations and inform the strategic planning of subsequent drainage activities.
Source: Applied Sciences
DOI: 10.3390/app14167207
Authors: Qingwei Wang, Qiang Yan, Yan Zhang, Xiafan Xing, Cailian Hao
Language: English
Subfield: Ocean Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,728
Award: G1339864048
OpenAlex ID: W4401643246