红格矿深还原—熔分过程及钒、铬走向的研究

深还原—熔分固相还原后的金属化球团生产钒铬生铁是利用红格矿的途径之一.由于V2O5与Cr2O3的赋存、分布以及冶炼过程中的走向基本一致,综合回收利用二者可一起考虑.为了提高钒、铬回收率,实现钛和铁的有效分离,通过单因素试验考察了在氩气保护下,配料的碱度、深还原—熔分温度和配碳量对熔分过程和钒、铬走向的影响.结果表明,当熔渣碱度为1.2,配碳量为0.5%,熔分时间为15 min,熔分温度为1 610℃时,渣铁的分离效果较好,且有利于钒、铬熔于铁相.

熔分深还原电炉炉衬侵蚀原因分析及提高炉龄措施

对熔分深还原电炉冶炼钒钛磁铁矿金属化球团过程中炉衬、出铁口及出渣口等部位耐火材料的侵蚀情况作了简要介绍,并对侵蚀原因进行了深入分析,认为高温、渣中氧化物对砖衬的化学侵蚀、渣铁的物理冲刷作用等是造成熔分深还原电炉耐火材料侵蚀严重的主要原因。针对熔分深还原电炉实际情况,提出了防止金属化球团氧化、控制冶炼温度、对炉衬进行热喷补是目前三种行之有效的提高熔分电炉炉龄的措施。

稀硫酸浸出富集深还原钛渣

用稀硫酸浸出深还原钛渣，富集渣中的ＴｉＯ_２。对深还原钛渣中不同氧化物在浸出过程中的反应和变化进行了研究和分析。

攀枝花钒钛磁铁矿深还原渣酸解工艺研究

在攀钢开发的非高炉冶炼钒钛磁铁矿的新流程中,钒钛磁铁矿转底炉直接还原渣铁分离部分完成了工业试验,获得了含钒铁水和含二氧化钛质量分数为43%左右的深还原渣。对深还原渣的化学成分及物相特点进行了分析,系统研究了预处理、酸矿质量比、反应酸质量分数、引发温度、熟化温度等因素对深还原渣酸解率的影响,找到深还原渣的最佳酸解工艺参数,为采用硫酸法回收深还原渣中的钛奠定了基础。实验结果表明,深还原渣经预处理,其酸解率较未处理高出10%左右。预处理后的深还原渣最佳酸解条件：酸矿质量比为（1.7~1.8）∶1,反应酸质量分数为88%~89%,引发温度为100~120℃,熟化温度为220℃。

深还原钛渣硫酸法制取钛白实验研究

以含钛铁精矿直接还原冶炼的含钛物料(深还原钛渣)为原料,对硫酸法制取颜料级钛白粉的工艺进行了研究。实验结果表明,深还原钛渣具有良好的酸解性能,酸解率可达97%;酸解后得到的钛液过滤性能好;但酸解钛液中氧化镁和氧化铝浓度过高,所以直接以该钛液为原料制得的钛白颜料性能差。采用深还原钛渣和钛精矿按一定比例混合酸解,可以避免钛液杂质含量过高对最终钛白产品质量造成的影响。深还原钛渣较佳用量为不高于钛原料总质量的20%。

钒钛磁铁矿金属化球团熔分-深还原过程热量损失以及影响钒入铁因素分析

对钒钛磁铁矿金属化球团熔分-深还原过程热量损失进行了计算,讨论了熔分温度、二元碱度、熔分渣中FeO含量、钛走向以及铁水中Si含量对钒进铁影响。结果表明：熔分过程的热量损失为6.34%左右;熔分温度为1 570℃,二元碱度为1.1-1.2,熔分渣中FeO的含量为8%-12%,合理控制配碳比以及适当的提高铁水中的Si含量,有利于熔分过程中钒进铁。

深还原渣制钛硅铁合金试验研究

用深还原渣为原料，硅铁和石灰作还原剂和熔剂添加剂，在电弧炉中电硅热还原冶炼铁硅铁合金。钛硅铁合金产品在１５０ｋｇ中频感应炉取代３０ＴｉＦｅ，成功冶炼出含Ｔｉ钢种。

钒钛磁铁矿金属化球团熔分深还原试验研究

用氢气还原制得钒钛磁铁矿的金属化球团,在马弗炉内进行熔分深还原试验。通过正交试验和单因素试验研究了熔分还原温度、碱度、萤石配比和还原时间对生铁钒含量以及铁和钒的回收率的影响,发现碱度和时间为影响生铁钒含量、铁和钒回收率的主要因素,并找出熔分深还原的最优工艺条件。在此条件下,渣铁分离良好,生铁中钒的质量分数为0.59%,铁和钒的回收率分别达到了95.39%和92.49%。

Coal-based reduction mechanism of low-grade laterite ore

A low-grade nickel laterite ore was reduced at different reduction temperatures. The morphology of metallic particles was investigated by scanning electron microscopy （SEM） and energy dispersive spectroscopy （EDS）. Experimental results indicate that the metallic nickel and iron gradually assemble and grow into larger spherical particles with increasing temperature and prolonging time. After reduction, the nickel laterite ore obviously changes into two parts of Fe-Ni metallic particles and slag matrix. An obvious relationship is found between the reduction of iron magnesium olivine and its crystal chemical properties. The nickel and iron oxides are reduced to metallic by reductant, and the lattice of olivine is destroyed. The entire reduction process is comprised of oxide reduction and metallic phase growth.

钛渣炉在钒钛磁铁矿冶炼新工艺流程中的应用

通过对钒钛磁铁矿在常规冶炼工艺流程和新工艺流程的生产实践的研究,分析了钛渣炉在常规工艺流程与新工艺流程中的不同应用功能,并对比了相关工艺参数,提出了钛渣炉在新的工艺流程中主要担当了熔分深还原的作用,最终达到铁、钒、钛分离及回收的目的。

Efficient enrichment of nickel and iron in laterite nickel ore by deep reduction and magnetic separation

The process of deep reduction and magnetic separation was proposed to enrich nickel and iron from laterite nickel ores.Results show that nickel-iron concentrates with nickel grade of 6.96%,nickel recovery of 94.06%,iron grade of 34.74%,and iron recovery of 80.44% could be obtained after magnetic separation under the conditions of reduction temperature of 1275℃,reduction time of 50 min,slag basicity of 1.0,carbon-containing coefficient of 2.5,and magnetic field strength of 72 kA/m.Reduction temperature and time affected the possibility of deep reduction and reaction progress.Slag basicity affected the composition of slag in burden and the spilling and enriching rate of nickel-iron from a matrix to form nickel-iron particles.Nickel-iron particles were generated,aggregated,and grew gradually in the reduction process.Nickel-iron particles can be effectively separated from gangue minerals by magnetic separation.

Meta-analysis of commercial Pt/C measurements for oxygen reduction reactions via data mining

The rotating disk electrode technique is commonly used for screening and characterizing the performance of electrocatalysts for the oxygen reduction reaction(ORR).However,a reliable performance comparison of different electrocatalysts from different labs remains a challenge because of the inconsistency in the measurement of commercial Pt/C.Commercial Pt/C has been adopted extensively as a reference for evaluating the ORR performance of a new electrocatalyst.However,the reported ORR performances of commercial Pt/C from different labs could be significantly different because of multiple factors.Herein,we conducted a meta‐analysis of the ORR performance of commercial Pt/C via data mining of the literature.This revealed the optimal testing conditions for the most repeatable ORR performance,with commercial Pt/C in both acid and alkaline electrolytes;the optimal Pt loading was 20μg/cm^(2) on a 4 mm glassy carbon working electrode.The value of 0.84±0.03 V was suggested as the“Golden reference”of the commercial Pt/C(with Pt 20 wt%)ORR half‐wave potential for the performance evaluation of other ORR catalysts in both acid and alkaline electrolytes.The conclusion obtained through the meta‐analysis was confirmed by experiments.This study provides general guidance for a reliable measurement of the ORR performance of commercial Pt/C as a reference.

熔分电炉冶炼金属化球团过程炉衬侵蚀分析

对熔分深还原电炉冶炼钒钛磁铁矿金属化球团过程中熔分电炉炉衬、出铁口及出渣口等部位耐火材料的侵蚀情况作了介绍,并对侵蚀原因进行了分析。电弧侵蚀、渣中氧化物的化学侵蚀、炉渣碱度不当、砖缝和裂纹等是造成熔分深还原电炉耐火材料侵蚀严重的主要原因,其中电弧侵蚀和渣中氧化物侵蚀尤为重要,占到侵蚀比例的70%以上。