THE GAS HYDRATE PROCESS FOR SEPARATION OF CO2 FROM FUEL GAS MIXTURE: MACRO AND MOLECULAR LEVEL STUDIES

• Main Authors: Ripmeester, John A., Englezos, Peter, Kumar, Rajnish
• Language: English
• Published: 2008
• Subjects: International Conference on Gas Hydrates 2008; ICGH 2008; carbon dioxide; gas separation; gas hydrates; Raman spectroscopy; Hydrogen; Integrated Coal Gasification Combined Cycle
• Online Access: http://hdl.handle.net/2429/1023

The “Integrated Coal Gasification Combined Cycle” (IGCC) represents an advanced approach for green field projects for power generation. This process requires separation of carbon dioxide from the shifted-synthesis gas mixture (fuel gas). Treated fuel gas consists of approximately 40% CO2 and rest H2. Gas hydrate based separation technology for hydrate forming gas mixtures is one of the novel approaches for gas separation. The present study illustrates the gas hydrate-based separation process for the recovery of CO2 and H2 from the fuel gas mixture and discusses relevant issues from macro and molecular level perspectives. Propane (C3H8) is used as an additive to reduce the operating pressure for hydrate formation and hence the compression costs. Based on gas uptake measurement during hydrate formation, a hybrid conceptual process for pre-combustion capture of CO2 is presented. The result shows that it is possible to separate CO2 from hydrogen and obtain a hydrate phase with 98% CO2 in two stages starting from a mixture of 39.2% CO2. Molecular level work has also been performed on CO2/H2 and CO2/H2/C3H8 systems to understand the mechanism by which propane reduces the operating pressure without compromising the separation efficiency.