D0I:10.13374f.issn1001-053x.2012.03.016 第34卷第3期 北京科技大学学报 Vol.34 No.3 2012年3月 Journal of University of Science and Technology Beijing Mar.2012 高炉碱金属富集区域钾、钠加剧焦炭劣化新认识及其 量化控制模型 赵宏博，2)回 程树森2 1)北京科技大学钢铁治金新技术国家重点实验室，北京1000832)北京科技大学治金与生态工程学院，北京100083 园通信作者，E-mail:vezilong@yahoo..com.cm 摘要碱金属对高炉内焦炭的破坏大多通过研究碱金属碳酸盐对焦炭气化反应的影响，从而得出钾、钠破坏性相近，在控 制碱金属入炉时也基本不对二者进行区分：但高炉调研表明在碱金属富集明显加剧的区域碱金属碳酸盐已分解且焦炭中钾 含量均大于钠.本文通过热力学计算得知在碱富集区域碱金属主要以单质蒸气而非碳酸盐或氧化物形式存在，据此设计了模 拟此区域有无C02时钾、钠单质蒸气在焦炭上的自主吸附和破坏实验，结合原子吸收光谱法、X射线衍射法和扫描电镜能谱 分析发现钾蒸气和焦炭中灰分大量结合形成钾霞石后体积膨胀、裂纹扩展导致碱金属富集区域钾在焦炭上的吸附和破坏能 力均远大于钠，因此建议尽量采用低灰分焦炭并严格控制入炉钾负荷.进一步研究体系中不同钾蒸气含量对气化反应的影响 规律，得出当钾蒸气与焦炭的气固质量比率超过3%后焦炭反应性陡升.依据碱金属富集区域钾、钠在焦炭上的不同吸附和 破坏性，建立了钾、钠各自入炉上限及总量上限的量化控制模型. 关键词高炉：碱金属：蒸气：焦炭：灰分：劣化 分类号T℉549.9 New cognition on coke degradation by potassium and sodium in alkali enriched regions and quantificational control model for BF ZHAO Hong-bo,CHENG Shu-sen) 1)State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing,Beijing 100083,China 2)School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing.Beijing 100083,China Corresponding author,E-mail:vezilong@yahoo.com.cn ABSTRACT The effects of potassium and sodium on coke degradation are commonly thought to be similar by studying the influence of alkali carbonates on coke gasification,and the amounts of potassium and sodium into the blast furnace (BF)are controlled without considering the differences.But BF investigations indicate that alkali carbonates have decomposed and in coke the potassium content is always larger than the sodium content,where the enrichment of alkali metals is obviously aggravated.In this article it is found by ther- modynamic calculations that alkali metals exist as simple substance vapors instead of carbonates or oxides in the alkali enriched regions.Based on that,experiments for testing the autonomic absorption and damage of potassium and sodium vapors on coke with or without carbon dioxide were designed to simulate the alkali enriched regions.Atomic absorption spectrometry (AAS),X-ray diffraction (XRD)and scanning electron microscope-energy dispersive spectrometry (SEM-EDS)analysis reveal that the absorbance and damage of potassium vapor on coke are much larger than those of sodium vapor because of easy combination with ash in coke to form kaliophi- lite,which induces volume expansion and crack propagation.So it is proposed that the ash content in coke should be low and potassium into BF should be strictly controlled.Coke gasification tests with different contents of potassium vapor show a steep ascent in coke reac- tion index (CRI)when the mass ratio of potassium vapor to coke in the gas-solid system is above 3%.According to the different absorption and damage effects of potassium and sodium on coke,quantificational control models are constructed for determining the up- per limits of potassium and sodium as well as the total amount into BF. KEY WORDS blast furnaces:alkali metals:vapor:coke:ash:degradation 收稿日期：2011-02-10 基金项目：国家自然科学基金资助项目(60872147)：中央高校基本科研业务费专项资金资助项目第 34 卷 第 3 期 2012 年 3 月 北京科技大学学报 Journal of University of Science and Technology Beijing Vol． 34 No． 3 Mar． 2012 高炉碱金属富集区域钾、钠加剧焦炭劣化新认识及其 量化控制模型 赵宏博1，2) 程树森1，2) 1) 北京科技大学钢铁冶金新技术国家重点实验室，北京 100083 2) 北京科技大学冶金与生态工程学院，北京 100083 通信作者，E-mail: vczilong@ yahoo． com． cn 摘 要 碱金属对高炉内焦炭的破坏大多通过研究碱金属碳酸盐对焦炭气化反应的影响，从而得出钾、钠破坏性相近，在控 制碱金属入炉时也基本不对二者进行区分; 但高炉调研表明在碱金属富集明显加剧的区域碱金属碳酸盐已分解且焦炭中钾 含量均大于钠． 本文通过热力学计算得知在碱富集区域碱金属主要以单质蒸气而非碳酸盐或氧化物形式存在，据此设计了模 拟此区域有无 CO2 时钾、钠单质蒸气在焦炭上的自主吸附和破坏实验，结合原子吸收光谱法、X 射线衍射法和扫描电镜--能谱 分析发现钾蒸气和焦炭中灰分大量结合形成钾霞石后体积膨胀、裂纹扩展导致碱金属富集区域钾在焦炭上的吸附和破坏能 力均远大于钠，因此建议尽量采用低灰分焦炭并严格控制入炉钾负荷． 进一步研究体系中不同钾蒸气含量对气化反应的影响 规律，得出当钾蒸气与焦炭的气固质量比率超过 3% 后焦炭反应性陡升． 依据碱金属富集区域钾、钠在焦炭上的不同吸附和 破坏性，建立了钾、钠各自入炉上限及总量上限的量化控制模型． 关键词 高炉; 碱金属; 蒸气; 焦炭; 灰分; 劣化 分类号 TF549 + . 9 New cognition on coke degradation by potassium and sodium in alkali enriched regions and quantificational control model for BF ZHAO Hong-bo 1，2) ，CHENG Shu-sen1，2) 1) State Key Laboratory of Advanced Metallurgy，University of Science and Technology Beijing，Beijing 100083，China 2) School of Metallurgical and Ecological Engineering，University of Science and Technology Beijing，Beijing 100083，China Corresponding author，E-mail: vczilong@ yahoo． com． cn ABSTRACT The effects of potassium and sodium on coke degradation are commonly thought to be similar by studying the influence of alkali carbonates on coke gasification，and the amounts of potassium and sodium into the blast furnace ( BF) are controlled without considering the differences． But BF investigations indicate that alkali carbonates have decomposed and in coke the potassium content is always larger than the sodium content，where the enrichment of alkali metals is obviously aggravated． In this article it is found by ther￾modynamic calculations that alkali metals exist as simple substance vapors instead of carbonates or oxides in the alkali enriched regions． Based on that，experiments for testing the autonomic absorption and damage of potassium and sodium vapors on coke with or without carbon dioxide were designed to simulate the alkali enriched regions． Atomic absorption spectrometry ( AAS) ，X-ray diffraction ( XRD) and scanning electron microscope-energy dispersive spectrometry ( SEM-EDS) analysis reveal that the absorbance and damage of potassium vapor on coke are much larger than those of sodium vapor because of easy combination with ash in coke to form kaliophi￾lite，which induces volume expansion and crack propagation． So it is proposed that the ash content in coke should be low and potassium into BF should be strictly controlled． Coke gasification tests with different contents of potassium vapor show a steep ascent in coke reac￾tion index ( CRI) when the mass ratio of potassium vapor to coke in the gas-solid system is above 3% ． According to the different absorption and damage effects of potassium and sodium on coke，quantificational control models are constructed for determining the up￾per limits of potassium and sodium as well as the total amount into BF． KEY WORDS blast furnaces; alkali metals; vapor; coke; ash; degradation 收稿日期: 2011--02--10 基金项目: 国家自然科学基金资助项目( 60872147) ; 中央高校基本科研业务费专项资金资助项目 DOI:10.13374/j.issn1001-053x.2012.03.016