120025 20240319081004.0 doi 10.1007/s12649-022-01833-7 sideral 130828 ART-2022-130828 eng Arévalo, Roberto CFD analysis of co-firing of coke and biomass in a parallel flow regenerative lime kiln 2022 Access copy available to the general public Unrestricted The lime industry is a highly energy intensive industry, with a huge presence worldwide. To reduce both production costs and pollutants emissions, some lime production plants are introducing more environmentally-friendly energy sources, such as local agro-industry residues. In this paper, a numerical tool is presented, which simulates a large-scale Parallel Flow Regenerative (PFR) kiln that currently uses coke as main fuel. The developed tool aims at investigating the combustion process under conditions of co-firing of coke and biomass and to assist the plant operators in the optimization of such operating conditions. To achieve this goal, a two-way coupling Euler–Lagrange approach is used to model the dynamics of the particulate phase and their interaction with the gas phase. Pyrolysis, volatiles oxidation and char oxidation are modelled by kinetics/diffusion-limited model (for heterogeneous reactions) and mixture fraction approach (for homogeneous reactions). Moreover, two methods are investigated for representing the limestone bed: a porous medium (PM) approach and a “solid blocks” (BM) tridimensional mesh. Comparison of the results for the case of 100% coke showed that the ideal “blocks” method is more accurate as it adequately simulates the scattering of fuel particles through the PFR kiln anchor, which is limited with the PM approach. Moreover, the temperature profile, maximum and minimum temperatures, as well as CO2 and O2 concentrations at outlet, are comprised in the expected range for this technology, according to available literature. Finally, the predicted results of a co-firing case with 60% biomass (in mass) were validated with measurements in an industrial facility, with production capacity of 440 calcium oxide tons per day. The results suggest that the model is fairly accurate to predict gas temperature, as well as O2 and NOX concentrations at the kiln outlet. Although some improvements are recommended to refine the CFD predictions, these promising results and the high computational efficiency laid the foundation for future modelling of co-firing of coke and biomass, as well as the modelling of the lime calcination process. It also paves the way for facilitating the reduction of pollutant emissions thus contributing to a more sustainable lime production. info:eu-repo/grantAgreement/EC/H2020/636865/EU/Flexible Superheated Steam Torrefaction and Grinding of Indigenous Biomass from Remote Rural Sources to Produce Stable Densified Feedstocks for Chemical and Energy Applications/SteamBio This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 636865-SteamBio info:eu-repo/semantics/openAccess by http://creativecommons.org/licenses/by/3.0/es/ 3.2 2022 ENVIRONMENTAL SCIENCES 146 / 275 = 0.531 2022 Q3 T2 0.599 2022 Environmental Engineering 2022 Q2 Waste Management and Disposal 2022 Q2 Renewable Energy, Sustainability and the Environment 2022 Q2 6.9 2022 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Rezeau, Adeline (orcid)0000-0002-9310-7864 Herce, Carlos 13 (2022), 4925-4949 Waste and biomass valorization WASTE AND BIOMASS VALORIZATION 1877-2641 4179107 http://zaguan.unizar.es/record/120025/files/texto_completo.pdf Versión publicada 1925460 http://zaguan.unizar.es/record/120025/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:120025 articulos driver 2024-03-18-14:25:55 ARTICLE