Hybrid hydrate processes for CO2/H2 mixture purification: A techno-economic analysis.

In this work, hydrate based separation technique was combined with membrane separation and amine-absorption separation technologies to design hybrid processes for separation of CO 2 /H 2 mixture. Hybrid processes are designed in the presence of different types of hydrate promoters. The conceptual processes have been developed using Aspen HYSYS. Proposed processes were simulated at different flow rates for the feed stream. A comprehensive cost model was developed for economic analysis of novel processes proposed in this study. Based on the results from process simulation and equipment sizing, the amount of total energy consumption, fixed cost, variable cost, and total cost were calculated per unit weight of captured CO 2 for various flow rates of feed stream and in the presence of different hydrate promoters. Results showed that combination of hydrate formation separation technique with membrane separation technology results in a CO 2 capture process with lowest energy consumption and total cost per unit weight of captured CO 2. As split fraction and heat of hydrate formation increases, the share of hydrate formation section in total energy consumption increases. When TBAB is applied as hydrate promoter, due to its higher hydrate separation efficiency, more amount of CO 2 is captured in hydrate formation section and consequently the total cost for process decreases considerably. Hybrid hydrate-membrane process in the presence of TBAB as hydrate promoter with 29.47 US$/ton CO 2 total cost is the best scheme for hybrid hydrate CO 2 capture process. Total cost for this process is lower than total cost for single MDEA-based absorption process as the mature technology for CO 2 capture. • Hydrate-based separation was combined with membrane and chemical absorption technologies to purify CO 2 /H 2 mixture. • The processes were designed and simulated in the presence of different hydrate promoters. • Techno-economic study was performed to estimate energy consumption, operating cost, and fixed cost of proposed processes. • Hybrid hydrate-membrane process in the presence of TBAB has the lowest total cost as 29.47 US$/ton CO 2. [ABSTRACT FROM AUTHOR]