摘要
焦炭作为重要的炼铁原料,其热态性能的优劣备受关注。而同一种焦炭使用不同热性质评价体系(CRI、CSR、CRR_(25)、CSR_(25))得到的结果可能完全不同,根源在于对焦炭溶损反应机理的认知不够深入全面。焦炭发生溶损反应过程中,气体非等摩尔扩散这一因素常常被忽略,导致对焦炭溶损反应机理的认知出现偏差。为了能够更加清晰全面地了解焦炭溶损反应机理,建立了考虑气体非等摩尔扩散的溶损反应动力学模型,进行了工业焦炭与CO_(2)在1100~1300℃溶损达到25%的气化反应试验,通过对比考虑和不考虑气体非等摩尔扩散的CO_(2)内扩散有效系数、CO_(2)在焦炭内部浓度有效区域和反应限制环节,说明了气体非等摩尔扩散对焦炭溶损反应的影响。结果表明,考虑气体非等摩尔扩散的情况下,CO_(2)内扩散有效系数减小,且随着温度、反应进程和焦炭内部半径而改变;CO_(2)在焦炭内部浓度有效区域随温度上升开口减小、面积减小、位置降低且更靠近焦炭表面,溶损反应区域减小;反应限制环节随反应进行无明显变化趋势,始终保持稳定。
As an important raw material for ironmaking,coke has attracted much attention in terms of its thermal properties.The results obtained by different thermal property evaluation methods(CRI,CSR,CRR_(25),CSR_(25))for the same coke may be completely different,which is due to the lack of in-depth and comprehensive understanding of coke solution-loss reaction mechanism.In the process of coke solution-loss reaction,the factor of gas non-equimolar diffusion is always ignored,which leads to the deviation in understanding of coke solution-loss reaction mechanism.In order to understand the coke solution-loss reaction mechanism more clearly and comprehensively,a kinetic model considering gas non-equimolar diffusion was established.The gasification experiments of industrial coke and CO_(2) with 25%solution-loss at 1100-1300℃were carried out.The effect of gas non-equimolar diffusion on coke solution-loss reaction was explained by comparing the CO_(2) effective internal diffusion coefficient,the effective area of CO_(2) concentration in coke and the reaction controlling step with and without consideration of gas non-equimolar diffusion.The results show that with considering the gas non-equimolar diffusion,the CO_(2) effective internal diffusion coefficient decreases and changes with temperature,reaction process and internal radius of coke.With increase of temperature,the effective area of CO_(2) concentration in coke decreases,as well as the opening,area and position,and it is closer to the coke surface,meanwhile,the region of solution-loss reaction decreases.The reaction controlling step has no obvious variation trend and remains stable with the reaction process.
作者
黄浚宸
汪琦
张松
HUANG Jun-chen;WANG Qi;ZHANG Song(School of Materials and Metallurgy,University of Science and Technology Liaoning,Anshan 114051,Liaoning,China;Key Laboratory of Chemical Metallurgy Engineering Liaoning Province,University of Science and Technology Liaoning,Anshan 114051,Liaoning,China)
出处
《钢铁》
CAS
CSCD
北大核心
2022年第3期16-26,共11页
Iron and Steel
基金
国家自然科学基金资助项目(51704216)。
关键词
高炉炼铁
焦炭
溶损反应
气体非等摩尔扩散
动力学
模型
blast furnace ironmaking
coke
solution-loss reaction
gas non-equimolar diffusion
kinetics
model
作者简介
黄浚宸,男,生于1987年10月,博士,E-mail:864566818@qq.com.至今在辽宁科技大学材料与冶金学院冶金工程系担任讲师,是辽宁省化学冶金工程重点实验室成员。主要从事焦炭溶损劣化机理和矿-焦耦合机理的研究;通讯作者:汪琦(1960-),男,博士,教授,E-mail:wangqi8822@sina.com。
