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为了探明动态氧化条件下含钛高炉熔渣中金属铁的聚集、长大及沉降行为,通过高温氧化实验研究氧化时间、空气搅拌强度和纯氧氧化对金属铁沉降的影响.此外,还研究动态氧化过程中熔渣的温度与黏度变化情况,计算金属铁在熔渣中的沉降速度.实验室与1200 kg中试实验结果表明,向熔渣鼓入氧化性气体,低价钛化合物减少,熔渣温度升高,黏度减低,促进金属铁聚集、长大和沉降分离.氧化时间过长,熔渣中(FeO)与低价钛化合物基本消失,金属铁回收率下降.氧化终点的判断应以保留一定含量(FeO)与低价钛为依据. 相似文献
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介绍了SKS炼铅工艺的生产实践,并从渣型、鼓风炉还原能力及操作等方面探讨了降低鼓风炉渣含铅的途径和方法。 相似文献
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介绍了SKS炼铅工艺的生产实践,并从渣型、鼓风炉还原能力及操作等方面探讨了降低鼓风炉渣含铅的途径和方法。 相似文献
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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. 相似文献
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采用粉末样品压片法制样,选出3组元素测量条件,建立能量色散X-射线荧光光谱法测定铅冶炼鼓风炉渣样品中Pb,Cu,Zn,S,FeO,SiO2和CaO等组分。试验了压片前的样品粉碎和研磨时间对测量强度的影响,选择和制备了校准样品,使用经验系数法校正了基体效应及元素间谱线重迭的影响,同时对颗粒度和矿物效应作了部分校正。在选定的最佳实验条件下,方法的检出限范围为0.002%~0.020%。用于鼓风炉渣样品中Pb,Cu,Zn,S,FeO,SiO2和CaO等组分的测定,相对标准偏差(n=10)在0.16%~0.90% 相似文献
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钒钛磁铁精矿经高炉冶炼后,其中的TiO2几乎全部进入炉渣.为了有效利用钛资源,以含TiO249.36%(质量分数)的熔分渣为原料,经加碱焙烧、酸浸和水解后,制备海绵钛生产用原料一富钛料,研究焙烧温度对TiO2浸出率的影响,以及水解酸度对钛的水解率的影响.结果表明,焙烧温度对熔分渣中TiO2的浸出率影响很大:在低于1 000℃温度下加碱焙烧后钛的浸出率不高,而在1 300℃加碱焙烧后钛的浸出率高达92.2%;通过控制最终的水解酸度,钛的水解率可达91.5%,水解后产物为白色或浅黄色,颗粒较细,粒度为0.2~0.5 μm,TiO2品位达98.50%,可作为生产海绵钛的原料. 相似文献
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高炉渗铝渣口的试验研究 总被引:4,自引:0,他引:4
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。 相似文献
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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. 相似文献
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Rakesh Kumar Sanjay Kumar S. Badjena S. P. Mehrotra 《Metallurgical and Materials Transactions B》2005,36(6):873-883
Ground granulated blast furnace slag (GGBFS) is known to possess latent hydraulic activity, i.e., it shows cementitious properties when in contact with water over a long period of time. Results are presented in this article
to show that, in sharp contrast to published literature on the hydration of neat GGBFS, the complete hydration of slag is
possible in a short time (days), even without a chemical activator. This is achieved if the slag used for hydration is mechanically
activated, using an attrition mill. The nature of the hydration product of the mechanically activated slag depends not only
on the initial specific surface area (SSA) of the slag but also on the surface activation, as manifested by the change in
the zeta potential (ξ) of the slag during the milling process. Depending upon the SSA and the ξ, the hydration product changed from nonreacted slag with high porosity (slag SSA < 0.3 m2/g, ξ>−29 mV) to hydrated slag with a compact structure (SSA=0.3 to 0.4 m2/g, ξ=−29 to −31 mV), and, finally, to fully hydrated slag with high porosity (SSA>0.4 m2/g, ξ ∼ 26 mV). Unlike the poorly crystalline hydration product formed by the nonactivated slag, even after prolonged hydration
for years, the hydration product of mechanically activated slag was crystalline in nature. The crystallinity of the product
improved as the duration of the mechanical activation increased. The calcium-silicate-hydrate (C-S-H) phases present in the
slag hydration product, characterized by a Ca/Si ratio of 0.7 to 1.5, were similar to those found for the hydraulic cement
binder, except for the presence of Mg and Al as impurities. In addition, the presence of a di-calcium-silicate-hydrate phase
(α-C2SH), which normally forms under hydrothermal conditions, and a Ca-deficient and Si-Al-rich phase (average Ca/Si mole ratio
< 0.1 and Si/Al ∼ 3) is indicated, especially in the hydration product of slag that was activated for a longer time. 相似文献
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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. 相似文献
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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。 相似文献