Abstract

The carbothermic reduction of chromium from the Cr₂O₃–FeO–CaO–SiO₂–MgO–Al₂O₃ oxide system is subjected to thermodynamic simulation in the temperature range 1673–1973 K at a step of 50 K, a total pressure of 0.1 MPa, and an amount of nitrogen of 2.24 m³. The oxide system is represented by the chromium ore (wt %) 38 Cr₂O₃, 11.1 FeO, 0.17 CaO, 15 SiO₂, 29.7 MgO, 6 Al₂O₃, and low-carbon ferrochromium slag. It contains (wt %) 13 Cr₂O₃, 4 FeO, 41.6 CaO, 21.2 SiO₂, 12.8 MgO, and 7.4 Al₂O₃ and is added to the ore in an amount of 0, 5, 10, and 20%. Carbon is used as a reducing agent, and its consumption is increased by 10% from the stoichiometry for the reduction of Fe and Cr and by 8% of the metal mass for the formation of iron, chromium, and silicon carbides. The thermodynamic simulation is carried out using the HSC Chemistry 6.12 (Outokumpu, Finland) software package. The thermodynamic data of the CrO(II) compound are introduced into the database, and the thermochemical characteristics of the compounds existing in the database, namely, CaCr₂O₄, SiC, Cr₃C₂, Cr₇C₃, Cr₂₃C₆, Fe₃C, and Al₄C₃, are refined. The results of thermodynamic simulation demonstrate that an increase in the process temperature from 1673 to 1973 K increases the reduction of chromium (η_Cr) at various slag contents in the system. An increase in the slag content in the system from 0 to 20% decreases η_Cr from 94.8 to 94% at 1973 K. The reduction of chromium is maximal for the system composition with 0% slag. The chemical composition of the metal at a 1973 K and 0% slag is (wt %): 65.6 Cr, 22.7 Fe, 0.26 Si, and 11.5 C. The thermodynamic simulation results can be used to develop a technology for producing a chromium-containing alloy when a low-carbon ferrochromium slag is involved in metallurgical processing.

中文翻译：

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Cr 2 O 3 –FeO–CaO–SiOO–SiO 2 –MgO–Al 2 O 3氧化物体系中铬的热还原反应的热力学模拟

摘要

从Cr ₂ O ₃ –FeO–CaO–SiO ₂ –MgO–Al ₂ O ₃氧化物体系中铬的碳热还原在1673–1973 K的温度范围内以50 K的总压力进行热力学模拟的氮含量为0.1 MPa，氮含量为2.24 m ³。氧化系统由铬矿（重量％）38表示的Cr ₂ ö ₃，11.1的FeO，0.17的CaO，15的SiO ₂，29.7的MgO，6的Al ₂ ö ₃，和低碳铬铁炉渣。它包含（％重量）的Cr 13 ₂ ö ₃，4的FeO，41.6的CaO，21.2的SiO ₂，12.8 MgO和7.4的Al₂ O _3，并以0、5、10和20％的量添加到矿石中。碳用作还原剂，从化学计量上讲，碳和铁的消耗量比铁和铬的还原量增加了10％，而铁，铬和碳化硅的形成则使金属的消耗量增加了金属质量的8％。使用HSC Chemistry 6.12（芬兰奥托昆普，软件包）进行热力学模拟。将CrO（II）化合物的热力学数据引入数据库，然后数据库中存在的化合物的热化学特性即CaCr ₂ O ₄，SiC，Cr ₃ C ₂，Cr ₇ C ₃，Cr ₂₃ C ₆精炼Fe ₃ C和Al ₄ C ₃。热力学模拟的结果表明，在这个过程中温度到1973 k时的增加，从1673增加铬的还原（η_的Cr在系统中的各种炉渣内容）。在从0至20％在系统中的熔渣含量的增加而减小η_的Cr从94.8到94％，在1973 K的还原铬是用于与0％熔渣系统组成最大。在1973 K和0％炉渣下金属的化学成分为（wt％）：65.6 Cr，22.7 Fe，0.26 Si和11.5 C.热力学模拟结果可用于开发生产含铬的技术冶金过程中涉及低碳铬铁渣时的合金。