Preparation of glass-forming materials from granulated blast furnace slag

Glass precursor materials, to be used for the vitrification of hazardous wastes, have been prepared from blast furnace slag powder through a sol-gel route. The slag is initially reacted with a mixture of alcohol (ethanol or methanol) and mineral acid (HNO₃ or H₂SO₄) to give a sol principally consisting of Si, Ca, Al, and Mg alkoxides. Gelation is carried out with variable amounts of either ammonia or water. The gelation rate can be made as fast as desired by adding excess hydrolizing agent or else by distilling the excess alcohol out of the alkoxide solution. The resulting gel is first dried at low temperature and ground. The powder thus obtained is then heat treated at several temperatures. The intermediate and final materials are characterized by thermal analysis, infrared (IR) spectroscopy, X-ray diffraction, scanning electron microscopy (SEM), and chemical analysis. From the results, the operating conditions yielding a variety of glass precursors differing in their composition are established. The method, in comparison with direct vitrification of slag, presents a number of advantages: (1) the glass precursor obtained devitrifies at higher temperatures; (2) it enables the adjustment, to a certain extent, of the chemical composition of the glass precursor; and (3) it permits recovering marketable materials at different stages of the process.     

钢渣-矿渣-钡渣基胶凝材料水化过程强化

针对钢渣(SS)矿渣(GBFS)钡渣(BS)复合胶凝材料水化硬化慢的问题,提出一种活性激发晶种强化的方法,以加速水化硬化过程.通过正交试验设计得到活性激发剂配比(质量分数)为煅烧脱硫石膏11％、铝酸钙3％、元明粉0.75％.利用含该激发剂的胶凝材料快速预水化制备复合晶种,能够显著促进胶凝材料水化结晶过程,提高早期强度,...     

高炉渣皮脱落分析

渣皮脱落是困扰高炉生产问题之一。它使炉墙及冷却壁热面温度急剧升降,产生很大的热震,使炉墙及冷却壁本体产生裂纹或侵蚀。渣皮进入炉缸后,导致炉温波动,甚至严重炉冷。边缘煤气分布较重是渣皮脱落的根本原因。适当发展边缘,能够消除渣皮脱落。     

高炉渗铝渣口的试验研究

开发的渣口渗铝工艺设备简单,易于操作,主要工艺参数如下:渗铝剂配比为铝粉10％,氧化铝粉88％,氯化铵2％;加热温度为850℃;保温时间11h。渗铝层具有耐高温、耐磨损、抗氧化、与基材结合强度高等特性。生产试验表明,渗铝渣口的使用寿命比普通渣口高2.28倍。     

流渣反应器内含钛高炉渣的流动特性

针对含钛炉渣在流渣反应器中的氧化工艺,采用模型实验方法研究熔渣在反应器内的流动特性与溶质扩散现象.考虑气液两相流动时,由于界面张力和浮力作用,黏性力的影响相对降低,故采用水来代替实际的高温液态高炉渣,通过底部吹入N2,模拟实际反应器内的流动情况.设计并排与错排两种喷吹方式,分别进行了物理水模型实验及数值模拟实验研究.物理水模型实验分别采用高速摄像法观测流场和刺激响应法测传质过程;数值模拟实验分析了不同位置的速度矢量分布和湍动能分布.结果表明错排喷吹方式的反应器内的流动特性好于并排方式.     

高炉渣微晶玻璃体系中的析晶行为

本文以CaO、MgO、Al_2O_3和SiO_2四种氧化物为主要原料,辅以Cr_2O_3、CaF_2和Fe_2O_3为复合晶核剂,B_2O_3为助熔剂,通过高温熔融工艺制备微晶玻璃.系统地研究了四种主要原料的配比对微晶玻璃析晶行为、微观结构、晶相组成及理化性能的影响.通过DTA对基础玻璃的析晶动力学进行分析;通过SEM和XRD对微晶玻璃的微观结构和晶相组成进行分析;通过测定抗折强度、密度及抗酸碱性腐蚀对微晶玻璃的理化性能进行评价.本文创新性地以晶体平均生长指数作为正交试验的研究指标,研究表明:最优的原料配比质量分数为CaO:32%,MgO:13%,Al_2O_3:8%,SiO_2:47%,按此比例混合原料制得的试样经XRD分析得知其结晶相为单一的铝透辉石,衍射峰相比较于其他试样较强,结晶度较高;以此配比制得微晶玻璃制品其晶体平均生长指数高达2.91;最优配比制得的试样抗折强度为147.4MPa,体积密度为3.03g/cm~3,耐酸碱性腐蚀的质量损失率分别为0.37%和0.047%,各项理化性能在各组试样的比较中均处于最优水平.     

高炉渣排氯能力的试验

 为找到合理有效的炉渣排氯制度,使得炉渣排氯能力最大化,在对高炉内氯元素进行热力学分析的基础上,研究了高炉渣的化学成分、温度以及恒温时间对排氯能力的影响。结果表明,高炉渣的排氯率随着炉渣碱度的提高而增加;其排氯率随温度的增加而降低;随[w(MgO)]的增加,其排氯率先增加后降低;随[w(Al2O3)]的增加,其排氯率先增加,当渣中[w(Al2O3)]超过16%时,其对炉渣排氯率的影响不大;随着恒温时间的延长,炉渣的排氯率降低。高炉在保证正常生产的前提下,应适当地提高炉渣碱度,降低高炉渣温度和增加出渣铁次数,[w(MgO)]和[w(Al2O3)]应保持在11.0%和16.0%左右,以提高炉渣的排氯能力,减少氯元素对高炉冶炼和后续设备产生的不利影响。     

由熔融高炉渣制备微晶玻璃

采用熔融法,由熔融高炉渣制备性能稳定的基础玻璃.通过对基础玻璃的差热分析确定微晶玻璃的热处理工艺制度.结合X射线衍射分析、扫描式电子显微镜观察等现代研究方法,确定了微晶玻璃热处理制度的最佳工艺参数,并研究了微晶玻璃的晶体生长方式.微晶玻璃的热处理最佳工艺参数为:核化温度850℃,保温1.5 h;晶化温度935℃,保温1 h.玻璃首先从表面开始析晶,然后逐步向内部生长.实验所得微晶玻璃的力学性能,如抗折强度、耐酸碱性和硬度,均优于天然大理石.     

Selecting optimal slag conditions in the blast furnace

In selecting the best chemical composition of slag melts, it is expedient to take account of their viscosity and electrical conductivity, which are structure-sensitive properties. The viscosity and electrical conductivity of blast-furnace slag are studied experimentally. To permit correct selection of the slag conditions in the blast furnace, a parameter is proposed for assessing the relation between the structural particles of the melt: the heterogenization temperature, which takes account of the viscosity and electrical conductivity of the slag melts. The discharge temperature of the slag from blast furnace 8 at PJSC ArcelorMittal Kryvyi Rih is measured. Comparison of the actual discharge temperature of the slag and the calculated heterogenization temperature for blast furnace 8 permits identification of the optimal slag basicity (CaO/SiO₂).     

高炉炉渣脱硫能力分析

为研究高炉炉渣脱S能力、降低铁水含S量,针对某高炉S负荷进行来源分析,对其炉渣数据进行了热力学分析,得到了铁水Si含量、炉渣碱度以及出铁速度对炉渣脱S能力的影响规律,并提出了改善炉渣脱S能力的措施。     

Experimental simulations of primary slag formation in blast furnace

Abstract

Primary slag formation of the blast furnace ferrous burden was experimentally simulated using synthetic MgO-Al₂O₃-CaO-SiO₂ slags with FeO, Na₂O, or FeS additions. The combined effect of FeO and Na₂O or FeS was also examined. The melting behaviour and viscosity of five different base slags (sinter, pellet, or lump ore) were investigated using optical dilatometry, thermogravimetric-differential thermal analysis (TGA-DTA), and viscometric analysis. The results indicate the importance of FeO (wüstite) in the formation and nature of liquid primary slags. Solidus temperature, fusion temperature, solidus-fusion interval, and viscosity were all significantly affected by FeO. A clear, but not simple or linear, tendency showed a lowering of the solidus and fusion temperatures and a concomitant decrease of the viscosity with increased FeO addition. The presence of Na₂O or FeS in the slag system, alone or combined with the FeO addition, created an initial melting at lower temperatures, but the liquid volume produced was limited. The effect of the added components was distinctly different on different base slag systems. It is proposed that the effect is fundamentally dependent on the chemical or, more exactly, on the mineralogical composition of the base slag systems at the initial stage of the melting. The results of the experiments are considered to represent reasonable simulations of the melting behaviour of the corresponding primary slags of the blast furnace ferrous burden in the cohesive zone.     

高炉渣的偏振化能量色散X射线荧光光谱分析

用带有Mo,Al2O3和HOPG3个次级靶的偏振化能量色散X射线荧光光谱仪,成功地分析了高炉渣中MgO,Al2O3,CaO,SiO2,S,TiO2,MnO和TFe。高炉渣中主要成分SiO2,Al2O3,CaO,MgO相互之间的干扰,使用Luscas Tooth和Price经验系数法校正。总的测量时间为600s,结果能满足冶金生产的要求。     

利用不锈钢尾渣及矿渣制砖的试验研究

通过利用不锈钢尾渣及矿渣制砖的试验,确定了不锈钢尾渣及矿渣制砖的合理配比。在此基础上,开发了激发不锈钢尾渣及矿渣活性的技术。结果表明:配加质量分数分别占0.4%、0.6%的Na2SO4和NaCl作为激发剂,可激发不锈钢尾渣及矿渣的活性,使砖的抗压强度最大提高了42.6%。     

含钛高炉渣渣钛分离研究

对某钢厂高钛型高炉渣进行了渣钛分离研究,确定了以NaOH作为分离剂制取偏钛酸晶体粉末的工艺路线,实现了合钛高炉渣资源的有效利用.含钛高炉渣中的钛、硅、铝氧化物在高温下与NaOH发生发应,生成相应的含氧酸钠盐,经过水浸和酸洗即可得到偏钛酸结晶.实验表明,温度对分离效果的影响显著,当渣与分离剂之比为50∶33、焙烧温度达1 350℃时,效果最佳,生成的偏钛酸量最大.     

Silicon distribution between blast furnace slag and hot metal

Abstract

Analyses of slag and hot metal in daily average samples from a 1033 m³ blast furnace charged with 100% self-fluxing sinter, and published data from two 2000 m³ furnaces with different proportions of various pellet types in the charge, have been used to calculate the ‘silicate capacity’ of slag and to investigate the effects of basicity and temperature on silicate capacity and silicon distribution ratio. Regression equations have been developed which show that both silicate capacity and silicon distribution ratio increase with increasing basicity and decreasing temperature. The temperature effect is very large compared with the influence of slag basicity. Similar relationships between silicate capacity and temperature are obtained individually for both furnace types as well as by combining their data together and with the data from other furnaces. Silicon distribution ratios calculated by using the silicate capacity of the slag compare well with the results found from slag and metal analyses.     

锰矿洗炉对高炉渣的影响及其机理

 利用锰矿洗炉是处理高炉炉缸堆积事故的重要方法之一。对MnO质量分数不同时的炉渣性能及其机理进行研究,应用熔体物性综合测定仪测定含MnO炉渣的黏度及熔化性温度,并提出稳定性指数的概念;使用X射线衍射仪（XRD）分析含MnO炉渣的物相组成;利用拉曼光谱仪研究含MnO炉渣的微观状态。试验结果表明,锰矿洗炉过程中,炉渣中MnO最佳质量分数应为1.5%左右,此种炉渣在1 480 ℃时的黏度为0.25 Pa·s左右,熔化性温度为1 340 ℃左右,稳定性较强,可以满足洗炉要求。锰矿洗炉的机理是炉渣中生成了锰橄榄石类硅酸盐低熔点物质,增大了液态炉渣的过热度;并且随着自由氧离子浓度的增加,其促使复杂硅氧四面体网络结构解聚为简单硅氧四面体结构,炉渣由复杂结构向简单结构发展,从而显著降低炉渣黏度,达到洗炉的目的。     

鼓风炉熔炼高铅氧化渣的生产实践

叙述了鼓风炉熔炼高铅渣的生产实践,介绍了延长鼓风炉和电热前床使用寿命,提高鼓风熔炼能力和降低渣含铅所采取的措施和取得的效果。