Reduction Rate of Ferrous Oxide in Smelting Reduction

ＲｅｄｕｃｔｉｏｎＲａｔｅｏｆＦｅｒｒｏｕｓＯｘｉｄｅｉｎＳｍｅｌｔｉｎｇＲｅｄｕｃｔｉｏｎＬｉｕＱｉｎｇｃａｉ①ＡＢＳＴＲＡＣＴＲｅｄｕｃｔｉｏｎｒａｔｅｏｆｆｅｒｏｕｓｏｘｉｄｅｉｎｓｍｅｌｔｉｎｇｒｅｄｕｃｔｉｏｎｗｉｔｈｉｒｏｎｂａｔｈｈａｓ...     

Characteristics of Nitrogen Jet and Its Effect on the Bath in Slag Splashing

ＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆＮｉｔｒｏｇｅｎＪｅｔａｎｄＩｔｓＥｆｆｅｃｔｏｎｔｈｅＢａｔｈｉｎＳｌａｇＳｐｌａｓｈｉｎｇＹａｎｇＷｅｎｙｕａｎ①，ＺｈｅｎｇＣｏｎｇｊｉｅ①，ＢａｉＲｕｉｇｕｏ②，ＦｕＺｈｅｎｒｏｎｇ②，ＺｈａｎｇＸｉｎｇｌｉ...     

Study on Metallurgical Reaction in Molten Steel with Coal-Oxygen Injection

ＳｔｕｄｙｏｎＭｅｔａｌｕｒｇｉｃａｌＲｅａｃｔｉｏｎｉｎＭｏｌｔｅｎＳｔｅｅｌｗｉｔｈＣｏａｌ┐ＯｘｙｇｅｎＩｎｊｅｃｔｉｏｎＬｉｕＬｉｕ①ＡＢＳＴＲＡＣＴＢｙｔｅｃｈｎｏｌｏｇｉｃａｌｅｘｐｅｒｉｍｅｎｔｓｏｎｂｏｔｏｍｐｕｌｖｅｒｉｚｅｄｃｏａ...     

Effects of the Electrodes’ Shape and Graphite Quality on the Arc Stability During Hydrogen Plasma Smelting Reduction of Iron Ores

Reducing greenhouse gases (GHG), especially CO₂, is necessary to counteract climate change. The European steel industry currently corresponds to 5.7% of the total EU emissions and must therefore minimize their GHG fractions in the future. One of the most promising technologies to eliminate CO₂ emissions while directly reducing iron ore to steel in a single step is the hydrogen plasma smelting reduction. The stability of the plasma arc, which is determined by the properties and geometry of the graphite electrode, has a substantial impact on the process’ economic feasibility. To study the arc stability concerning the graphite quality, tip geometry, and electrode gap, a series of experiments is conducted. The results are evaluated to create stability maps and fields to identify stable process parameters. The geometry of the graphite cathode shows the primary influence on arc stability. Tips with a flat end (standard version) offering the most unstable and a machined step on the graphite cathode providing the most stable conditions. However, an additional coating to prevent side arcing leads to the deterioration of the arc. The two graphite grades tested, with different maximum grain sizes and price classes, show no great relevance to the stability of the arc.     

Studies on the Reduction–Swelling Behaviors of Hematite Iron Ore Pellets with Noncoking Coal

Studies on the reduction and swelling behaviors of fired pellets, made by mixing hematite iron ore fines of ?100, ?18 + 25, and ?10 + 16 mesh sizes in different proportions, were carried out with low-grade coal in the temperature range of 850–1000°C with an aim to promote the massive utilization of fines in ironmaking. The rate of reduction in all the fired iron ore pellets increased markedly with an increase in temperature up to 1000°C and it was more intense in the first 15-min soak time. Relatively higher reduction rates and swellings/shrinkage were observed in the pellets made by the addition of larger size (+100 mesh) particles in the matrix of ?100 mesh size fines. In general, highest swelling was observed in the fired pellets at a reduction temperature of 850°C, followed by a decrease at 900°C. At both these temperatures, the percentage of swelling increased with reduction time up to the range studied (120 min). The fired pellets reduced at temperatures of 950°C and 1000°C, showed shrinkage, and the extent of this shrinkage increased with increase in exposure time at 950°C. The percentage swelling/shrinkage in the fired pellets was found to be related to their crushing strengths and porosities.     

Study on the Shaft-Direct Reduction Process with Cold Bound Pellet

ＳｔｕｄｙｏｎｔｈｅＳｈａｆｔ┐ＤｉｒｅｃｔＲｅｄｕｃｔｉｏｎＰｒｏｃｅｓｗｉｔｈＣｏｌｄＢｏｕｎｄＰｅｌｅｔＱｉＹｕａｎｈｏｎｇ，ＺｈｏｕＹｕｓｈｅｎｇ，ＸｕＨａｉｃｈｕａｎ，ＹｕＪｉｎｇｆｅｎｇ，ＣａｉＡｉｐｉｎｇ①ＡＢＳＴＲＡＣＴＴｈｅｍｅｔａ...     

Equilibrial of AI-N and Nb-N in Molten Iron

ＥｑｕｉｌｉｂｒｉａｏｆＡＩ－ＮａｎｄＮｂ－ＮｉｎＭｏｌｔｅｎＩｒｏｎＣＨＥＮＸｉａｏＹｉ，ＨＡＭＱｉＹｏｎｇ，ＳＯＭＧＢｏａｎｄＷＡＨＧＲｏｎｇＺｈｕＥｑｕｉｌｉｂｒｉａｏｆＡＩ－ＮａｎｄＮｂ－ＮｉｎＭｏｌｔｅｎＩｒｏｎ￥ＣＨＥＮＸｉａｏＹｉ，ＨＡ...     

Fundamental Research of Making Stainless Steel by Smelting Reduction of Chromite

ＦｕｎｄａｍｅｎｔａｌＲｅｓｅａｒｃｈｏｆＭａｋｉｎｇＳｔａｉｎｌｅｓｓＳｔｅｅｌｂｙＳｍｅｌｔｉｎｇＲｅｄｕｃｔｉｏｎｏｆＣｈｒｏｍｉｔｅＤｕＴｉｎｇ；ＹｏｕＸｉａｏｍｉｎ；ＷｕＹｉｅｍｉｎｇＡｂｓｔｒａｃｔ：Ｔｗｏｐｒｏｃｅｓｓｅｓｏｆｍａｋｉｎ...     

Phosphorous Enrichment in Molten Adjusted Converter Slag：Part II Enrichment Behavior of Phosphorus in CaO-SiO_2-FeO_x-P_2O_5 Molten Slag

 The enrichment behavior of phosphorus in CaO-SiO2-FeOx-P2O5 slag was studied by making an investigation on the distribution of phosphorous content in the CaO-SiO2-FeOx-P2O5 molten slag. The research results showed that the 2CaO·SiO2 solid particles existing in molten slag were the condensation sites for the phosphorus enrichment. The enrichment process of phosphorus in the molten slag can be recognized as three substeps: mass transfer of phosphorus from bulk slag to the surface of 2CaO·SiO2 particle, superficial solid solution reaction of phosphorus around the 2CaO·SiO2 particle, and diffusion of phosphorus through the product layer of 2CaO·SiO2-3CaO·P2O5 solid solution to the inner of 2CaO·SiO2 particle. Moreover, higher temperature is favorable to the phosphorous enrichment from molten bulk slag to the 2CaO·SiO2 particles.     

钛渣连续熔炼渣铁界层凝固机理及控制探讨

探讨了高功率全密闭直流电炉连续熔炼钛渣过程中渣铁界层的凝固机理及控制措施。分析表明,渣铁界层钛渣中夹杂有少量金属铁,且越接近界面铁量越大,渣铁温差、界层钛渣TiO2还原程度较高等是造成界层易于凝固的重要原因;通过调整渣层厚度、熔炼温度、还原程度等可对凝固范围进行有效控制。     

铁水熔池处理高炉瓦斯灰的发泡过程

实验测定了不同条件下高炉瓦斯灰在铁水熔池中还原产生的内生气源对发泡过程泡沫渣高度的影响，应用泡沫高度随时间变化的实验数据和发泡性能方程确定了发泡特性参数。在铁浴熔融还原时，为保证较高的传热和反应速率，熔池中泡沫应保持一个适当的高度，按此原则，通过实验结果对铁水熔池处理高炉瓦斯灰工艺参数的选择提出了建议。     

氧化锌矿火法处理新工艺——铁浴熔融还原法

提出了氧化锌矿火法处理的新工艺——铁浴熔融还原法 ,分析了其工艺原理 ,用该工艺试验研究制得的锌氧粉 w Zn O95 %～ 98% ,w Pb O1.6 %～ 2 .5 % ,锌挥发率 >93%。     

铁浴式熔融还原的终还原反应研究现状

介绍了铁浴式熔融还原终还原反应的机理,各区域的还原反应及总还原速率模型的研究情况,并阐述了终还原反应的研究现状以及存在的问题,可供有关研究了工作及生产技术人员参考。     

铜冶炼渣选铜尾矿还原焙烧—磁选回收铁工艺研究

以炭粉为还原剂,通过还原焙烧—磁选工艺从铜冶炼渣选铜尾矿中回收铁,考察了影响铁回收效果的主要工艺参数,并通过试验验证。结果表明,在炭粉用量为铜渣量的25%、氧化钙用量为铜渣量的10%、焙烧温度1 300℃、焙烧时间1.5h、焙烧产物磨细度为-0.074mm占55%的条件下,磁选精矿(即还原铁粉)铁含量可达92.16%,尾矿铁含量可降低至3.91%,铁回收率87.65%。     

铜渣熔融还原回收铁试验研究

以铜浮选尾渣为原料,采用直接熔融还原—磁选的方法回收铁,探讨了在焙烧温度为1 350℃时,碳粉、氧化钙用量及焙烧恒温时间对还原渣磁选过程铁回收率与铁精矿品位的影响。结果表明,在碳粉和氧化钙添加量分别为铜渣质量的32%和10%、恒温100min的条件下对浮选尾渣进行熔融还原,焙烧后的产物破碎磨细至-0.074mm占85%,再进行弱磁选,可获得铁品位为67.47%的还原铁精矿,铁回收率为92.32%。     

铁浴式熔融还原型熔体的性质

研究了铁浴式熔融还原型熔体的组成与性质的关系，测试了熔体对耐火材料的浸润性，分析了熔体中ＦｅＯ浓度，熔体温度，耐火材料的组成及结构，耐火材料中石墨碳含量等对熔体与耐火材料间浸润性的影响，同时测试了熔体组成与流动性的关系，熔体中ＦｅＯ浓度，熔渣碱度对熔体的熔化温度的影响，测定和分析了熔体组成与粘度变化的关系，结果表明，熔中ＦｅＯ浓度是影响熔体性质的最关键因素，ＦｅＯ浓度提高，熔体对耐火材料的润湿能力     

熔融还原合成渣中碳还原Fe2O3的发泡特性参数

测定了Fe₂O₃在熔融还原合成渣中被碳还原时,还原气体产生泡沫渣的高度与时间的关系.由发泡特性参数方程计算了不同条件下的发泡特性参数,从而可以对熔融还原过程中由内生气源引起的发泡过程进行定量描述。为在铁浴中控制泡沫渣现象提供了必要的基础.     

中高锰铁水冶炼技术的探讨

转炉用高锰铁水冶炼存在金属喷溅、冶炼终点钢水余Mn含量偏低、冶炼操作不易控制等问题。通过充分利用终点Mn与渣系碱度、氧化铁间的关系特性,优化冶炼操作,达到提高冶炼余Mn含量、稳定冶炼操作的目的,终点余Mn含量由0.125%提高到0.196%,提升了铁水中Mn的利用率,减少了后期合金化操作成本。     

高镁型红土镍矿熔融还原冶炼渣型探究

提出了采用熔融还原工艺冶炼红土矿生产高镍含量(Ni20%)镍铁合金的技术路线。通过查阅相图、热力学计算、熔渣热物性质测定,提出了高MgO渣型的冶炼方案,并验证了FeO-SiO_2-CaO-MgO-Al_2O_3五元渣系的冶金性能。分析了MgO对渣型的影响,结果表明,MgO含量21%~22%的渣型有较低的熔化温度和适宜的黏度;熔炼试验渣中NiO可控制到0.05%以下。