Multi-Scale Modeling and Simulation of Intensified Reactive-Separation Processes for Hydrogen Production and CO2 Capture via the Water-Gas Shift Reaction (WGSR)
As a result of fossil fuels-based energy production, reducing atmospheric carbon dioxide emissions has become an urgent issue. Especially, carbon capture and storage (CCS) technology, being one of the leading processes to reduce total carbon emissions, has become increasingly important. Hydrogen is an important energy carrier, and hydrogen-based technologies have increased in importance recently due to the worldwide focus on green processes.
The Integrated Gasification Combined Cycle (IGCC) is a promising technology supplying clean energy at affordable prices. The IGCC process is currently being coupled with CCS technologies. However, using CCS technologies in power generation processes is a great challenge, necessitating the intensification of the coupled IGCC-CCS process. Process intensification (PI), leads to substantially smaller, cleaner, and more energy efficient processes, and is a prominent topic, receiving significant attention in recent years. As part of intensifying a process, integration of multiple operations (e.g., reaction and separation) in a single unit is often carried out, to improve the existing process efficiency, and to reduce energy consumption, and unwanted output/by-product generation.
The objective of this work is to demonstrate the process intensification potential of a technology, containing one or more water gas shift (WGS) reactor components seamlessly integrated with other plant components. We investigate the applicability of various (alternative to the conventional process) novel and efficient reactor configurations that include self-standing adsorptive reactor (AR)/membrane reactor (MR), and the combination of a MR-LTSR-AR-adsorptive separator (AS)-membrane separation (MS) units (herein after referred to as the LTSR-MS/LTSR-AS/AS-LTSR-AS/MR-AS/AS-MR-AS/MR-AR systems). The proposed WGS reactor technologies have the potential to generate highly efficient and ultra-compact processes, by producing H2 for use in IGCC with simultaneous CO2 capture.
Innovative designs of the proposed processes are determined based on the comprehensive modeling and design of the selected IGCC plant’s section. Comprehensive, multi-scale, multi-phase, computational fluid dynamics (CFD) models are developed for reaction/separation processes. Developed models quantify the many complex physicochemical phenomena occurring within the process, thus providing the basis to better understand, and intensify the overall system. Model predictions are generated for a broad range of operating conditions and design parameters, thus enabling a comparative performance assessment of the proposed process versus a conventional process for the proposed IGCC application.