136010 20260218073537.0 doi 10.1021/acs.energyfuels.4c00942 sideral 139004 ART-2024-139004 eng Maziarka, Przemyslaw Part 2 - Tailoring of pylolytic char properties with a single particle CFD model with a focus on the impact of shrinking, vapor cracking, and char permeability 2024 Access copy available to the general public Unrestricted The prediction of the structural properties of biobased carbonaceous materials of pyrolytic origin (chars) with only base feedstock properties and process conditions still poses a challenge that hinders char tailoring for novel applications. CFD modeling of single biomass particle conversion can help solve this issue since it allows for the quantification of relations between parameters that are difficult to measure. A model for char tailoring must include a validated representation of the structural changes coupled to all other relevant phenomena occurring during conversion. Part 2 of this study focuses on finding the description of the mentioned aspects to achieve the highest precision of prediction of the structural changes in char by a CFD model. The investigation in Part 2 is composed of three cases focused on accurate description and prediction of (1) bulk density and porosity, (2) secondary vapor reactions on yields and soot formation, and (3) permeability, as well as the outflux and conversion of evolved vapors. The experimental results from Part 1 and the literature data were used to find appropriate descriptions of phenomena and assess the accuracy of the model. The model results indicate that for both particle lengths (10 and 16 mm), a high accuracy of prediction of base structural parameters was achieved. The average prediction error for temperatures between 400 and 840 °C of bulk density was 31 ± 15 kg/m3, and the porosity was 1.8 ± 1.1 vol %. The results also show a low error in the prediction of bulk product yields (dry basis) over the mentioned temperature range, which were: for char 2.8 ± 1.1 wt %, for the condensable fraction 6.5 ± 3.3 wt %, and for the pyrolysis gas 4.1 ± 1.9 wt %. The distribution of secondary char formation was found to be nonuniform below 500 °C. The changes in permeability had a minor influence on the vapor outflux but a non-negligible effect on the soot formation, especially at 840 °C. The results indicate a need for further improvement of the primary degradation model to increase the accuracy of the effect of soot formation on the char structure. info:eu-repo/grantAgreement/EC/H2020/721991/EU/Advanced Carbon Materials from Biowaste: Sustainable Pathways to Drive Innovative Green Technologies/ GreenCarbon This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 721991- GreenCarbon info:eu-repo/grantAgreement/EC/H2020/731101/EU/ Biofuels Research Infrastructure for Sharing Knowledge II/BRISK II This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 731101-BRISK II info:eu-repo/semantics/openAccess All rights reserved http://www.europeana.eu/rights/rr-f/ 5.3 2024 ENGINEERING, CHEMICAL 42 / 176 = 0.239 2024 Q1 T1 ENERGY & FUELS 75 / 182 = 0.412 2024 Q2 T2 1.124 2024 Chemical Engineering (miscellaneous) 2024 Q1 Fuel Technology 2024 Q1 Energy Engineering and Power Technology 2024 Q1 9.5 2024 info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion Kienz, Norbert Dieguez-Alonso, Alba Prins, Wolter Arauzo, Pablo J. Skreiberg, Øyvind Anca-Couce, Andrés (orcid)0000-0002-0118-3254 Manyà, Joan J. Universidad de Zaragoza Ronsse, Frederik 5005 555 Universidad de Zaragoza Dpto. Ing.Quím.Tecnol.Med.Amb. Área Ingeniería Química 38, 11 (2024), 9772–9793 Energy fuels Energy and Fuels 0887-0624 1255936 http://zaguan.unizar.es/record/136010/files/texto_completo.pdf Postprint info:eu-repo/date/embargoEnd/2025-05-25 947921 http://zaguan.unizar.es/record/136010/files/texto_completo.jpg?subformat=icon icon Postprint info:eu-repo/date/embargoEnd/2025-05-25 oai:zaguan.unizar.es:136010 articulos driver 2026-02-17-20:48:26 ARTICLE