Simulation of sulfur deposition in sour gas reservoirs using the lattice Boltzmann method

High-sulfur gas reservoirs are a vital component of global natural gas resources, yet sulfur deposition during development can block flow channels and severely reduce production. This study employs a lattice Boltzmann-based multiphysics model to simulate sulfur deposition behavior. Results indicate that low-permeability reservoirs suffer the most severe damage due to their fine pore throats: after 100 days, porosity and permeability decrease by 34.09% and 71.37%, respectively. Increasing the production pressure difference from 2 MPa to 8 MPa significantly exacerbates deposition, with permeability impairment rising from 49.68% to 92.44% and deposited sulfur mass increasing by approximately 1.82 times. In contrast, temperature difference has a limited effect; raising it from 2 K to 8 K only reduces porosity from 26.14% to 24.96%. H2S content exhibits a near-linear positive correlation with deposition mass, with each 3% increase in H2S content adding about 30–35 mg of sulfur deposit. These findings provide theoretical guidance for managing sulfur deposition in high-sulfur gas reservoirs, highlighting the need to pay special attention to low-permeability zones and to carefully optimize production pressure difference.