Study on developing a novel continuous separation device and carbon dioxide separation by process of hydrate combined with chemical absorption

Hydrate-based carbon dioxide (CO2) separation from gas mixture has been extensively investigated for it being process simple and environmentally friendly. However, as the concentration of CO2 in the gas mixture decreases, the condition of the hydrate formation becomes very harsh. Therefore, it is significantly difficult for a single hydrate-based method to separation CO2 completely. In this work, the first set of device for continuously separating CO2 from gas mixture was developed on the base of the method of hydrate combined with chemical absorption. The process feasibility of the combined method and the device were proved through experimental study on CO2 separation from integrated gasification combined cycle (IGCC) syngas. The experimental results also indicated CO2 could be completely separated from the balance component, and the estimated energy cost for CO2 separation with the combined method is about (sic)209 per ton CO2, which is lower than that with cryogenic separation process by about 30.0%. The study provides scientific data and theoretical guidance for the industrial application of hydrate-based CO2 separation and capture in future.