Investigating the Reduction of Barium Sulfate Using Methane Through the Modified Grain Model

This research investigates the reduction of barium sulfate using methane under unsteady-state conditions employing the "modified grain model". This model incorporates diffusion resistance for each grain and alters pellet structure due to differences in molar volume between solid reactant and product components. Experimental validations were conducted at ۹۱۵ and ۱۰۱۵ °C with ۴۰% methane in a thermogravimetric apparatus. The reaction at ۱۰۱۵ °C was completed one hour earlier than at ۹۱۵ °C. The model demonstrated high accuracy, with mean absolute errors of ۵.۲% at ۹۱۵ °C and ۹.۷% at ۱۰۱۵ °C, compared to experimental data. After validation, the model predicted grain radius, porosity over time, and gas concentration distribution inside the pellet over time and height. The reaction resulted in a ۹% decrease in grain radius and a ۱۶% increase in pellet porosity.

کلیدواژه ها:

Barium sulfate reduction ، Methane reductant ، Modified grain model ، Experimental Validation ، changing pellet structure ، porosity prediction