Study on the Effect of H2S on the Adsorption of CH4, N2, and CO2 by Anthracite

In order to study the effect of H2S on gas adsorption in a coal seam, the adsorption characteristics of single-component CO2, CH4, N-2, and H2S and multicomponent H2S mixed with CO2, CH4, and N-2 by anthracite were simulated by using the Grand Canonical Ensemble Monte Carlo (GCMC) method. The results show that the adsorption capacity of CO2, CH4, N-2, and H2S in anthracite decreases with increasing temperature and increases with increasing pressure. The isothermal adsorption curves of CO2, CH4, N-2, and H2S and different proportions of H2S/CH4, H2S/N-2, and H2S/CO2 are highly consistent with the Langmuir equation, and the R-2 is above 0.99. Under different temperature and pressure conditions, the adsorption capacity of H2S and CO2 is stronger than that of coal for N-2 and CH4, and the adsorption capacity difference is about 3 mmol/g. There is competitive adsorption among H2S, CO2, CH4, and N-2, and H2S has a superior adsorption property. When H2S and other gases exist at the same time, the adsorption capacities of CH4, N-2, and CO2 are reduced by 48-60%, 81-91%, and 51-66%, respectively.