共生铁矿直接还原后超重力铁、渣低温分离及共生元素富集

Based on the effective separation of paragenetic elements from the typical multiple-component complex iron ores, the separation between solid iron and molten slag in their direct reduction products was proposed at a low temperature below the melting point of iron by super-gravity in the present project. Inevitably, iron-slag separation at the lower temperature would be benefical for preventing the migration of paragenetic elements like phosphorus into metallic iron, and thus the paragenetic elements like phosphorus, rare-earth and boron can be concentrated further in the separated slag by super gravity. This research is focused on four basic scientific problems, including the mineral evolution behaviors of iron and slag phases in the direct reduction product, the migration and transformation regularity of the paragenetic elements between iron and slag phases, and the iron-slag separation behavior at low temperature and the concentration regularity of paragenetic elements from the separated slags in a super-gravity field. Consequently, the obtained results of this project can provide the required information for iron-slag separation from the direct reduced multiple-component complex iron ores at low temperature, and concentration of the paragenetic elements in the separated slags by super gravity. And then the feasible process methods and key parameters would be built, promting the advancement of basic theory and techonlogy on super-gravity metallurgy.

基于典型复杂共生铁矿中共生元素的有效分离，本项目提出将超重力场引入到其直接还原产物的铁、渣分离过程之中，旨在低于铁熔点的低温条件下实现固态铁相与熔融渣相的分离。铁、渣低温分离能够阻止磷等共生元素向金属铁中的溶解，从而在超重力条件下实现共生元素如磷、稀土、硼等在渣中的富集。课题围绕复杂共生铁矿直接还原产物中铁相与脉石相的矿相演变行为，共生元素在铁相与渣相间的迁移转化规律，超重力环境下铁、渣的低温分离行为，以及超重力条件下渣中共生元素的富集规律等关键科学问题开展研究工作，为最大限度的实现共生铁矿直接还原后铁、渣的低温分离以及渣中共生元素的富集提供必要的基础数据，并建立可行的工艺方法与关键参数，推进超重力冶金在复杂共生铁矿利用领域的基础理论研究与技术开发。

本项目基于典型复杂共生铁矿中共生元素的有效分离，提出将超重力场引入到复杂共生铁矿直接还原产物的铁、渣分离过程之中，旨在低于铁熔点的低温条件下实现固态铁相与熔融渣相的分离，有效阻止磷等共生元素向金属铁中的溶解，从而在超重力条件下实现共生元素如磷、稀土、硼等在渣中的富集。首先，系统研究了高磷赤铁矿、白云鄂博矿、硼铁精矿等典型共生铁矿直接还原产物中铁相与脉石相的矿相演变行为，掌握了磷、稀土、硼等典型共生元素在铁相与渣相间的迁移转化规律，为铁、渣的低温分离以及渣中共生元素的富集提供了必要基础。然后，系统研究了超重力环境下铁晶粒的定向富集行为，掌握了铁、渣的低温分离规律，获得了最优的铁、渣低温分离条件，分别在1200℃、1100-1200℃、1250-1300℃的低温条件下实现了高磷赤铁矿、白云鄂博矿、硼铁精矿直接还原产物中铁、渣的高效分离。进一步系统研究了渣中共生元素的相态重构行为，掌握了超重力条件下共生元素相在渣中的富集规律，分别实现了渣中磷、稀土、硼的高效富集，为最大限度的实现共生铁矿直接还原后铁、渣的低温分离以及渣中共生元素的富集提供了必要的基础数据。在系统研究基础上，建立了可行的共生铁矿直接还原后超重力铁、渣低温分离以及渣中共生元素富集的工艺方法与关键参数。