TY  - EJOU
AU  - Chen, Siji 
AU  - Chen, Gang 
AU  - Wang, Wei 
AU  - Liu, Han 
AU  - Ouyang, Mukun 
AU  - Zhang, Wanhong 
AU  - Zhang, Lianghua 
AU  - Tang, Wei 
AU  - Hu, Shilai 

TI  - Simulation on H<sub><b>2</b></sub>S Migration and Elutriation during Cyclic Operationof Underground Sour Gas Storage
T2  - Energy Engineering

PY  - 2025
VL  - 122
IS  - 7
SN  - 1546-0118

AB  - The construction and operation of sulfur-containing gas storage are often more difficult than a non-sulfur storage facility due to the need to prevent environmental contamination from H<sub>2</sub>S leaks, as well as the corrosive effects of H<sub>2</sub>S on production facilities. Rapid elutriation of H<sub>2</sub>S from the reservoir during the construction of the gas storage is an effective way to avoid these problems. However, the existing H<sub>2</sub>S elutriation method has low efficiency and high economic cost, which limits the development of reconstructed gas storage of sulfur-containing gas reservoirs. To improve the efficiency of H<sub>2</sub>S elutriation in sulfur-containing gas reservoirs and enhance the economic benefits, a numerical simulation model of multiphase flow components was established to study the migration law of H<sub>2</sub>S in the multi-cycle operation of gas storage. Based on the H<sub>2</sub>S migrate law, the displacement H<sub>2</sub>S elutriation method was developed, and the elutriation mechanism and elutriation efficiency of the two methods were compared and analyzed. In addition, the main controlling factors affecting the H<sub>2</sub>S elutriation efficiency were investigated, and the H<sub>2</sub>S elutriation scheme of H gas storage was optimized. The results indicate that H<sub>2</sub>S migrates between near-well and far-well regions under pressure differentials. The traditional H<sub>2</sub>S elutriation method relies on concentration gradient diffusion, whereas the displacement elutriation approach leverages pressure differentials with higher H<sub>2</sub>S elutriation efficiency. For the displacement elutriation method, higher reservoir permeability enhances the peak-shaving capacity of the gas storage but has a minor impact on H<sub>2</sub>S elutriation when the formation permeability is between 30 and 100 mD. The elutriation efficiency is significantly higher when wells are drilled in the high structural parts of the reservoir compared to the low structural parts. Longer displacement elutriation time within a cycle improves H<sub>2</sub>S elutriation efficiency but reduces the working gas volume of the storage. Therefore, the optimal displacement time for H gas storage is 60 days. An optimized H<sub>2</sub>S elutriation scheme enabled the working gas to meet the national first-class natural gas standard within 10 cycles. This study elucidates H<sub>2</sub>S migration patterns, H<sub>2</sub>S elutriation mechanisms, and key influence factors on H<sub>2</sub>S elutriation efficiency, offering valuable technical insights for sour gas storage operations.
KW  - Underground sour gas storage; H<sub>2</sub>S migration; H<sub>2</sub>S elutriation; numerical simulation; elutriation efficiency

DO  - 10.32604/ee.2025.065481