Process Design and Techno-economic Analysis of Hybrid Hydrate-Amine Process for Pre-Combustion CO۲ Capture

Worldwide concerns over the threat of global warming have led industrialized countries to agree to reduce carbon emissions. Transition from fossil fuels to hydrogen energy is the most practical route to satisfying the net-zero emission concept. Hydrogen purification is one of the most critical rings of the hydrogen energy cycle. In this work a Hybrid Hydrate-Amine CO۲ capture process has been proposed for CO۲ removal from a simulated fuel gas stream (۴۰ mol% CO۲ + ۶۰ mol% H۲). The process is composed from one hydrate formation-dissociation stage and Amine absorption train. Tetrabutylammonium bromide (TBAB) was selected as hydrate formation thermodynamic promoter to decrease the hydrate formation pressure. An absorption/stripping process with Methyl diethanolamine (MDEA) solutions was applied to perform further CO۲ removal from effluent gaseous stream from hydrate formation reactor. The proposed processes were studied from techno-economic aspects by performing energy and economic analysis. The simulation results show that the duty is mainly consumed for cooling in hydrate formation reactor and steam consumption in stripper tower. As the result of the economic analysis of the proposed process, total cost for CO۲ capture calculated as ۵۹.۶۷ USD/ton CO۲ that is comparable with the cost of the standalone MDEA based amine pre-combustion CO۲ capture process.

Keywords:

Hydrogen , CO۲ capture , Gas hydrate , Process Design , Economic Analysis