摘要
碱金属在高炉中循环富集,对焦炭微观结构的侵蚀是导致其强度降低的重要因素之一。为全面阐明碱金属富集对焦炭微观结构的影响,采用单层蒸碱法对一种冶金焦炭Coke A开展了碱蒸气量为5%的纯K、纯Na和K-Na联合吸附试验,并利用多种手段对碱金属富集前后焦样的微观结构进行了综合表征。结果表明,相同碱蒸气量条件下,Coke A对Na的吸附量高于K,K富集会对焦炭宏观形貌产生明显破坏作用,扫描电镜图像显示K富集在组织中产生了扩孔和明显裂纹。碱金属富集浓度由外向内降低,侵蚀效果逐渐减弱。碱金属富集对微米孔有明显扩孔作用,而K、Na对纳米孔的影响恰好相反。碱金属富集能显著减少粗粒镶嵌组织含量,这可能是导致焦炭宏观性能降低的重要原因,其中K对焦炭宏观结构影响程度更大,可能与其对微晶结构产生较大破坏作用有关。本研究为深入认识碱金属富集对焦炭微观结构的侵蚀作用奠定了重要基础。
Alkali metals are cyclically enriched in blast furnace,and the erosion of coke microstructure is one of the important factors leading to decrease of coke strength.In order to comprehensively elucidate the effect of alkali metal enrichment on the microstructure of coke,the adsorption experiments of pure K,pure Na and K-Na combined with 5%alkali vapor content were carried out on Coke A using monolayer evaporation alkali method.The microstructure of coke samples before and after alkali metal enrichment was characterized by combination of various means.The results show that,under the same amount of alkali vapor,the adsorption capacity of Na by Coke A is higher than that of K.K enrichment has obvious destructive effect on the macroscopic morphology of coke,and the SEM images show that K enrichment produces pore expansion and obvious cracks in the organization.The concentration of alkali metal enrichment decreases from outside to inside,and the erosion effect is gradually weakened.Alkali metal enrichment has obvious effect on the pore expansion of micron pores,while K and Na have the opposite effect on nanopores.Alkali metal enrichment significantly reduces the content of coarse mosaic texture,which may be an important factor leading to the reduction of coke macroscopic properties.K has greater impact on coke macrostructure,which may be related to its greater destruction on microcrystalline structure.This study lays an important foundation for in-depth understanding of the erosion effect of alkali metal enrichment on coke microstructure.
作者
史春雷
程欢
肖璐颖
侯健
韩艳伟
孙章
SHI Chunlei;CHENG Huan;XIAO Luying;HOU Jian;HAN Yanwei;SUN Zhang(College of Chemical Engineering,North China University of Science and Technology,Tangshan 063210,Hebei,China;College of Science,North China University of Science and Technology,Tangshan 063210,Hebei,China;Manufacturing Department of Hansteel,HBIS Group Co.,Ltd.,Handan 056009,Hebei,China)
出处
《中国冶金》
CAS
CSCD
北大核心
2023年第6期21-32,共12页
China Metallurgy
基金
国家自然科学基金资助项目(51874136)
河北省自然科学基金——钢铁联合研究基金资助项目(E2019209447)
河北省高等学校科学技术研究项目——青年基金资助项目(QN2020217)。
关键词
碱金属
焦炭
高炉
光学组织
气孔结构
微晶结构
alkali metal
coke
blast furnace
optical texture
pore structure
microcrystalline structure
