eprintid: 10199840 rev_number: 7 eprint_status: archive userid: 699 dir: disk0/10/19/98/40 datestamp: 2024-11-11 10:07:59 lastmod: 2024-11-11 10:07:59 status_changed: 2024-11-11 10:07:59 type: article metadata_visibility: show sword_depositor: 699 creators_name: Lei, Timan creators_name: Luo, Kai H creators_name: Perez, Francisco E Hernandez creators_name: Wang, Geng creators_name: Yang, Junyu creators_name: Cano, Juan Restrepo creators_name: Im, Hong G title: Pore-scale study of CO2 desublimation and sublimation in a packed bed during cryogenic carbon capture ispublished: pub divisions: UCL divisions: B04 divisions: F45 keywords: Convection in porous media, solidification/melting, coupled diffusion and flow note: This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited. abstract: Cryogenic carbon capture (CCC) is an innovative technology to desublimate CO2 out of industrial flue gases. A comprehensive understanding of CO2 desublimation and sublimation is essential for widespread application of CCC, which is highly challenging due to the complex physics behind. In this work, a lattice Boltzmann (LB) model is proposed to study CO2 desublimation and sublimation for different operating conditions, including the bed temperature (subcooling degree ∆Ts), gas feed rate (Péclet number Pe) and bed porosity (ψ). The CO2 desublimation and sublimation properties are reproduced. Interactions between convective CO2 supply and desublimation/sublimation intensity are analysed. In the single-grain case, Pe is suggested to exceed a critical value Pec at each ∆Ts to avoid the convection-limited regime. Beyond Pec, the CO2 capture rate (vc) grows monotonically with ∆Ts, indicating a desublimation-limited regime. In the packed bed case, multiple grains render the convective CO2 supply insufficient and make CCC operate under the convection-limited mechanism. Besides, in small-∆Ts and high-Pe tests, CO2 desublimation becomes insufficient compared with convective CO2 supply, thus introducing the desublimation-limited regime with severe CO2 capture capacity loss (ηd). Moreover, large ψ enhances gas mobility while decreasing cold grain volume. A moderate porosity ψc is recommended for improving the CO2 capture performance. By analysing vc and ηd, regime diagrams are proposed in ∆Ts–Pe space to show distributions of convection-limited and desublimation-limited regimes, thus suggesting optimal conditions for efficient CO2 capture. This work develops a viable LB model to examine CCC under extensive operating conditions, contributing to facilitating its application. date: 2024-07-10 date_type: published publisher: CAMBRIDGE UNIV PRESS official_url: https://doi.org/10.1017/jfm.2024.351 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 2306916 doi: 10.1017/jfm.2024.351 lyricists_name: Lei, Timan lyricists_name: Luo, Kai lyricists_id: TLEIX16 lyricists_id: KLUOX54 actors_name: Luo, Kai actors_id: KLUOX54 actors_role: owner funding_acknowledgements: EP/W026260/1 [UK Engineering and Physical Sciences Research Council (EPSRC)]; [King Abdullah University of Science and Technology (KAUST)]; EP/X035875/1 [EPSRC under the project 'UK Consortium on Mesoscale Engineering Sciences (UKCOMES)'] full_text_status: public publication: Journal of Fluid Mechanics volume: 990 article_number: A6 pages: 42 issn: 0022-1120 citation: Lei, Timan; Luo, Kai H; Perez, Francisco E Hernandez; Wang, Geng; Yang, Junyu; Cano, Juan Restrepo; Im, Hong G; (2024) Pore-scale study of CO2 desublimation and sublimation in a packed bed during cryogenic carbon capture. Journal of Fluid Mechanics , 990 , Article A6. 10.1017/jfm.2024.351 <https://doi.org/10.1017/jfm.2024.351>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10199840/1/Luo%202024%20JFM%20sublimation.pdf