(244c) Optimal Selection of Solvent and Contactor Technology for Micro-Encapsulated Carbon Sorbent (MECS) Based CO2 Capture
AIChE Annual Meeting
Wednesday, November 17, 2021 - 8:50am to 9:15am
The present work evaluates different solvents and reactor configuration for MECS using process modeling and techno-economic analysis. The encapsulated solvents considered in this study are Na2CO3, ionic liquids, and piperazine. Required thermodynamic, reaction kinetics, and physical properties models of the solvents are developed based on the data obtained from the open literature. First, a rigorous capsule model is developed with an underlying solvent chemistry model that describes heat and mass transfer in the microcapsule. The results from the capsule model are validated with experimental data for the Na2CO3solvent . Two contactor technologies are evaluated: a fixed bed and a moving bed. These reactor models are 1-D non-isothermal, first principles-based models with appropriate mass transfer, hydro-dynamic, and momentum sub-models. The multi-scale reactor models incorporating the capsule model and embedded heat exchangers are implemented in Aspen Custom Modeler (ACM) where the method of lines is used to solve the resultant system of partial differential equations. The models simulate both absorption and regeneration stages of the process and study the impact of key design and operating parameters on the performance of MECS technology.
Techno-economic analysis of these reactor types operating with different solvents is carried out by computing their Equivalent Annual Operating Cost (EAOC) and comparing them with the traditional MEA technology . The capital cost of the reactor, compressors, and heat exchangers is estimated using Aspen Process Economic Analyzer (APEA) along with custom correlations. Operating costs include the cooling and heating utilities and compression cost for the flue gas, if any. Each combination of reactor type and solvent type is optimized for a fair comparison. It is observed that both reactor type and specific solvent have large impact on the economics of MECS technology.
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