Siderite is one of the abundant but refractory iron ore resources. Due to the low iron grade, low value-added product and inefficient utilization of siderite, this project aims to produce the high value-added iron carbide and realize the high-efficient utilization of siderite by adopting the carburization and magnetic separation method. The new approaches, including additives, mechanical activation, adding carbon inside pellets, pore forming materials, and pre-reduction, to solve the bottleneck problem of low efficient carburization and low separation efficiency of iron carbide and gangue are proposed. The functional mechanism researches of pre-reduction, adding carbon inside pellet, pore forming materials, mechanical activation, and additives are carried out to improve the carburizing gas diffusion in pellets and carburization reactions in iron grains, which is beneficial to enhance the carburization rate with the combined effects of pre-reduction, adding carbon inside pellets, mechanical activation and additives. Furthermore, the functional mechanisms of sodium salt, borate additive and mechanical activation are investigated to improve the embedded relationship between iron carbide and gangue and strengthen the growth of iron carbide particles, and also the liberation degree of iron carbide and gangue is improved. This project can provide new ideas and scientific support to the high-efficient utilization of siderite, and it also can supply the new raw iron carbide resource.
菱铁矿是一种储量丰富但尚不能被有效利用的复杂铁矿资源。针对目前菱铁矿铁品位低、制备的产品附加值不高、利用困难等问题,本项目拟采用渗碳-磁选法制备出附加值高、性能优良的碳化铁以实现菱铁矿的高效利用,并针对其中渗碳效率低、渗碳产物(碳化铁)和脉石的解离度不高等关键问题,提出采用添加剂、机械活化、内配碳、造孔剂和预还原等协同处理的新思路。通过本项目的研究,拟揭示预还原、内配碳、造孔剂、机械活化和添加剂等改善球团内渗碳气体扩散条件和强化铁晶粒内渗碳反应的作用机理,通过它们的协同作用,提高菱铁矿球团的渗碳速率;并进一步明晰钠盐、含硼添加剂和机械活化等改善碳化铁和脉石嵌布关系以及强化碳化铁颗粒长大的作用机理,通过这些措施的强化,提高碳化铁和脉石的解离度。研究成果不仅可为低品位复杂菱铁矿的高效利用提供新的思路和科学依据,而且可为碳化铁的原料增加新的来源。
菱铁矿是一种储量丰富但尚不能被有效利用的复杂铁矿资源。针对目前菱铁矿铁品位低、制备的产品附加值不高、利用困难等问题,本项目采用了渗碳-磁选法制备出附加值高、性能优良的碳化铁以实现菱铁矿的高效利用,并针对其中渗碳效率低、渗碳产物(碳化铁)和脉石的解离度不高等关键问题,提出了采用添加剂、机械活化、内配碳、造孔剂和预还原等协同处理的新方法。为此本项目取得的重要成果如下:成功揭示了预还原、添加剂等改善球团内渗碳气体扩散条件和强化铁晶粒内渗碳反应的作用机理,通过它们的协同作用,显著提高了菱铁矿球团的渗碳速率;项目进一步明晰了添加剂等改善碳化铁和脉石嵌布关系以及强化碳化铁颗粒长大的作用机理,通过这些措施的强化,极大提高了碳化铁和脉石的解离度,成功制备出铁回收率、铁品位和结合碳含量均很高的优质电炉炉料碳化铁,这与国内外已有的报道结果相比具有显著的优势。研究结果为低品位菱铁矿的高效利用提供了新的途径和科学依据。.本项目研究期间采用研究获得的相关结果发表基金资助论文7篇,其中在本领域权威期刊Journal of Alloys and Compounds、Metallurgical and materials transactions B、steel research international等高水平SCI期刊上发表论文6篇。项目研究期间运用高效渗碳方法及其强化机制、碳化铁和脉石的分离方法及其强化措施方面取得的研究结果申请相关发明专利5项,其中已有2项专利获得授权。