S.L. Zheng
,
Y. Zhang
金属学报(英文版)
A new method for chromate cleaning production named chromite caustic fusion pro-cess, is advanced by Institute of Chemical Metallurgy, the Chinese Academy of Sci-ences. With sodium hydroxide as reaction medium, the new process is composed ofthree procedures: liquid phase oxidation of chromite - metastable phase separation -carbonation ammonium transition. Generally illustrating the new process and its fea-tures, this paper mainly studies the thermodynamics of chromite oxidation. The newprocess has much better practical results than the conventional chromate productionprocess in which sodium carbonate is used as reaction medium. The superiority is alsoshown through thermodynamic studies.``
关键词:
chromite
,
null
,
null
,
null
,
null
Z. Sun
,
S.L. Zheng
,
Y. Zhang
,
null
,
null
,
null
,
null
,
null
,
null
,
null
,
null
,
null
,
null
,
null
,
null
,
null
,
null
金属学报(英文版)
Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.
关键词:
chromite
,
null
,
null
,
null
李磊
,
朱红波
,
彭金辉
,
张利波
,
代林晴
,
吴奎霖
钢铁
doi:10.7513/j.issn.1004-7638.2015.04.024
为高效利用铬铁矿粉,提出微波硅热还原铬铁矿粉冶炼低碳铬铁新工艺.采用FactSage软件对三元渣系(SiO2-CaO-Cr2O3)和二元渣系(SiO2-CaO)进行模拟,在模拟值基础上通过试验找出最佳工艺条件.结果表明:终点温度1 450℃,渣系二元碱度1.64条件下,反应过程中渣金可以实现良好分离,铬回收率达到81.03％.对产物物相和化学成分进行XRD、XRF分析可知,合金中不含渣相,其化学成分满足FeCr55C25Ⅱ牌号的要求.通过合金典型区域SEM图和X-射线能谱分析发现晶粒中含有少量Si杂质,碳主要存在于晶界上.
关键词:
铬铁矿
,
微波加热
,
硅热法
,
熔渣
,
低碳铬铁
高峰
,
吴尧鹏
,
刘军
,
何宏伟
,
康利涛
,
梁伟
无机材料学报
doi:10.3724/SP.J.1077.2013.12689
以低品位CLK6-62型铝矾土为主要原料,采用无压煅烧技术制备了铬铁矿掺杂的铝矾土基石油压裂支撑剂,并系统考察了铬铁矿添加量对试样物相、微结构及性能的影响.分析表明,铬铁矿掺杂有效促进了铬刚玉相和棒状莫来石相的发育,从而获得了具有双重增强机制的高强度试样.其中,铬铁矿添加量为2wt％时,试样烧结温度可降低60℃(从1480℃到1420℃),并且其在69 MPa闭合压力下的破碎率仅为1.8％(未掺杂试样:5.1％).该工艺采用低品位矿物原料及现有设备,所制备支撑剂性能高于相应标准要求,具有较好的推广前景.
关键词:
铝矾土
,
铬铁矿
,
石油压裂支撑剂
,
破碎率
刘衍辉
,
吕学伟
,
陈攀
,
白晨光
钢铁研究学报
doi:10.13228/j.boyuan.issn1001-0963.20150042
随着优质镍、铬资源的减少,越来越多低品位的红土镍矿和铬铁矿进入到铁合金的生产过程中,然而多数镍和铬的原料不能直接进入电炉,须经造块处理,改善其性能后入炉.主要围绕红土镍矿与铬铁矿复合烧结这一关键技术环节开展了实验研究与理论分析.烧结研究表明,红土矿与铬铁矿推荐比例为7∶3,适宜混合料水分为20％,适宜焦粉配比为13％;碱度为1.3时,各项烧结指标最优.蛇纹石的添加能够改善烧结矿质量,但效果不如添加CaO.推荐返矿配比为10％.复合烧结矿主要矿物是由尖晶石、铁橄榄石及少量铁酸钙(高碱度时)组成.固结方式是以液相粘接为主,液相主要由红土矿自身物质产生.
关键词:
红土矿
,
铬铁矿
,
复合烧结
,
固结机理
