{"title":"Numerical simulation of lignin gasification: The role of gasifying agents in entrained-flow reactors","authors":"","doi":"10.1016/j.tsep.2024.102878","DOIUrl":null,"url":null,"abstract":"<div><p>Biomass gasification using an Entrained-Flow Reactor (EFR) is an effective strategy for sustainable energy production and climate change mitigation. However, optimizing gasification efficiency and syngas quality requires a thorough understanding of the influence of gasifying agents. This study investigates the effects of different gasifying agents—air, CO<sub>2</sub>, steam, and CO<sub>2</sub>-steam mixtures—on lignin gasification in an EFR. Utilizing a validated Eulerian-Lagrangian Computational Particle Fluid Dynamics (CPFD) model, we examine how these agents impact biomass conversion to syngas, focusing on key parameters like hydrogen to carbon monoxide ratio, and the lower heating value (LHV) of syngas. Our findings reveal that air, due to nitrogen dilution, results in suboptimal lignin-to-syngas conversion, yielding lower energy content and hydrogen production. In contrast, steam enhances conversion efficiency, significantly increasing hydrogen output and LHV. CO<sub>2</sub> as a gasifying agent boosts carbon monoxide levels through interactions with solid carbon, leading to a higher energy content in the syngas. The CO<sub>2</sub>-steam mixture is particularly effective, producing syngas with a high hydrogen concentration, primarily due to the water–gas shift reaction and steam’s reaction with the lignin carbon. This research addresses the limitations of existing studies by providing detailed, quantitative insights into the impact of gasifying agents on lignin gasification in an EFR. By adjusting the CO<sub>2</sub>-to-steam ratio, operators can precisely control the composition of syngas for targeted applications such as Fischer-Tropsch synthesis, methanol production, and fermentation. The study highlights the potential of advanced simulation techniques to optimize biomass gasification processes, offering significant improvements in efficiency and energy yield over current methods.</p></div>","PeriodicalId":23062,"journal":{"name":"Thermal Science and Engineering Progress","volume":null,"pages":null},"PeriodicalIF":5.1000,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2451904924004967/pdfft?md5=0927802fb40a289f8518d53c059976cc&pid=1-s2.0-S2451904924004967-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Thermal Science and Engineering Progress","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2451904924004967","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENERGY & FUELS","Score":null,"Total":0}
引用次数: 0
Abstract
Biomass gasification using an Entrained-Flow Reactor (EFR) is an effective strategy for sustainable energy production and climate change mitigation. However, optimizing gasification efficiency and syngas quality requires a thorough understanding of the influence of gasifying agents. This study investigates the effects of different gasifying agents—air, CO2, steam, and CO2-steam mixtures—on lignin gasification in an EFR. Utilizing a validated Eulerian-Lagrangian Computational Particle Fluid Dynamics (CPFD) model, we examine how these agents impact biomass conversion to syngas, focusing on key parameters like hydrogen to carbon monoxide ratio, and the lower heating value (LHV) of syngas. Our findings reveal that air, due to nitrogen dilution, results in suboptimal lignin-to-syngas conversion, yielding lower energy content and hydrogen production. In contrast, steam enhances conversion efficiency, significantly increasing hydrogen output and LHV. CO2 as a gasifying agent boosts carbon monoxide levels through interactions with solid carbon, leading to a higher energy content in the syngas. The CO2-steam mixture is particularly effective, producing syngas with a high hydrogen concentration, primarily due to the water–gas shift reaction and steam’s reaction with the lignin carbon. This research addresses the limitations of existing studies by providing detailed, quantitative insights into the impact of gasifying agents on lignin gasification in an EFR. By adjusting the CO2-to-steam ratio, operators can precisely control the composition of syngas for targeted applications such as Fischer-Tropsch synthesis, methanol production, and fermentation. The study highlights the potential of advanced simulation techniques to optimize biomass gasification processes, offering significant improvements in efficiency and energy yield over current methods.
期刊介绍:
Thermal Science and Engineering Progress (TSEP) publishes original, high-quality research articles that span activities ranging from fundamental scientific research and discussion of the more controversial thermodynamic theories, to developments in thermal engineering that are in many instances examples of the way scientists and engineers are addressing the challenges facing a growing population – smart cities and global warming – maximising thermodynamic efficiencies and minimising all heat losses. It is intended that these will be of current relevance and interest to industry, academia and other practitioners. It is evident that many specialised journals in thermal and, to some extent, in fluid disciplines tend to focus on topics that can be classified as fundamental in nature, or are ‘applied’ and near-market. Thermal Science and Engineering Progress will bridge the gap between these two areas, allowing authors to make an easy choice, should they or a journal editor feel that their papers are ‘out of scope’ when considering other journals. The range of topics covered by Thermal Science and Engineering Progress addresses the rapid rate of development being made in thermal transfer processes as they affect traditional fields, and important growth in the topical research areas of aerospace, thermal biological and medical systems, electronics and nano-technologies, renewable energy systems, food production (including agriculture), and the need to minimise man-made thermal impacts on climate change. Review articles on appropriate topics for TSEP are encouraged, although until TSEP is fully established, these will be limited in number. Before submitting such articles, please contact one of the Editors, or a member of the Editorial Advisory Board with an outline of your proposal and your expertise in the area of your review.