This paper studied the gas separation and purification utilizing hydrate based gas separation (HBGS). The effect of nano porous media in split fractionation and the influencing of the composition of the feed gas were considered. Gas hydrate formation of ternary CH4/C2H6/C3H8 mixture were carried out in the fixed amount of water in the presence of nanostructure silica based material with the mass ratio of 5%. In this way, three different gas compositions were used as initial feed. After hydrate formation, the gas phase in equilibrium with the hydrate was used as a new feed for the next step of hydrate formation. The presence of porous media improved selectivity in methane purification. The continuous stepwise HBGS showed a good efficiency in selective gas separation. The change in the concentration of methane is significant specially when the amount of methane in the gas feeds are lower. Such an effect brought about by low dose of porous material can be utilized in the methane purification by HBGS. HWHYD software was applied to predict the equilibrium condition. Comparison of the equilibrium conditions in bulk system show the transfer of hydrate equilibrium curve to higher pressure and lower temperature due to the change in gas composition.
Finding economically method to separate valuable gas, some researchers tried to use gas hydrate formation technology. In this method, the preference of gas molecules in cage occupancy causes the fractionation . This is named hydrate based gas separation (HBGS). Increasing of the world CO2 gas production, as a by-product of combustion processes, gas hydrate formation was investigated as a possible solution for carbon dioxide separation. There are some pilot plants to research about HBGS that show this method should be studied in separation or purification of different gases. Utilization of multi-step CO2 hydrate formation was shown to be capable of capturing 68% CO2 from syngas at single pass in the presence of hydrogen sulfide and pure water. Surovtseva et al. used a combination of two low temperature processes, condensation at -55°C and the hydrate formation using hydrate promoters at 1°C for CO2 capture from gas stream. Their process produced hydrogen gas with purity more than 90% .
Publisher : 2nd National Iranian Conference on Gas Hydrate (NICGH)
By : N.Gholipour Zanjani1 , A.Zarringhalam Moghaddam , K. Nazari , M. Mohammad Taheri
File Information: English Language/ 9 Page / size: 646 KB
سال : 1392
ناشر : دومین کنفرانس ملی هیدرات گاز (NICGH)
کاری از : قلی پور زنجان , زرین قدم مقدم ,ناظری , اقای محمد طاهری
اطلاعات فایل : زبان انگلیسی / 9 صفحه / حجم : KB 646