Concentration and recovery of carbon dioxide from flue gas by vacuum swing adsorption

CO₂ released into the atmosphere are mainly attributed to fossil fuel combustion. The amount of CO₂ emission has to be cut down in the future due to global treaty. The concentration and recovery of CO₂ from flue gas is the first important step in solving CO₂ problem. This experimental study employs dual-bed vacuum swing adsorption (VSA), which does not generate another pollution problem, for CO₂ removal from flue gas and concentrates CO₂ in desorption stream. The comparison of two kinds of processes, four-step process and six-step process, is explored. The CO₂ product concentration in desorption step in the six-step process is higher than in the four-step process. The outlet CO₂ concentration in desorption step increases with detection time. The highest CO₂ concentration can be near 90%. The recovery of CO₂ is between 90% and 95%.