Study of Selected Factors Affecting Hydrate-Based Carbon Dioxide Separation from Simulated Fuel Gas in Porous Media

Abstract

Hydrate-based gas separation is one of the potential methods of carbon dioxide capture from fuel gases (CO2/H2) for an integrated coal gasification combined cycle (IGCC) power plant. In this study, the influences of selected factors, including porous properties, tetrahydrofuran (THF) concentration, sodium dodecyl sulfate (SDS) concentration, and initial pressure, of the operation system on hydrate phase equilibria, gas consumption, and gas separation are experimentally investigated by a designed orthogonal test method. It is found that the porous property is the most important factor on hydrate phase equilibria and CO2 gas separation, where the gas separation becomes better in silica gel. The presence of THF moderates the hydrate phase equilibrium and improves the gas consumption and CO2 gas recovery, and 3 mol % THF should be a suitable value for gas separation. The initial pressure has an important effect on the hydrate equilibrium pressure. With the increase of the driving force, the gas consumption increases, while the gas separation effect becomes worse.