SFCA系粘结相的物理化学性质及还原机制的基础研究

随着矿石来源的复杂化和多样化，烧结矿产质量势必会受到影响。改善烧结矿还原性能，提高软熔带透气性和煤气利用率，从而降低能耗和CO2排放，是高炉炼铁领域面临的必须解决的技术难题和社会问题。要想提高烧结矿质量，必须从铁酸钙粘结相入手，但铁酸钙本质的物理化学性质和还原机制尚不明确。结合国家自然科学基金“十三五”发展规划中的两项优先发展领域：“低碳炼铁”和“冶金关键物化数据”，申请人拟将复合铁酸钙从复杂的烧结矿体系中提炼出来，针对SiO2-Fe2O3-CaO-Al2O3（SFCA）系及其子系统展开研究，包括矿物结构分析、制备方式、物理化学性质、还原机制等。采用相图热力学分析、动力学建模与现代测试技术相结合的方式，确定SFCA流动性和表面张力等冶金关键物化数据，建立SFCA的热力学优势区域图和还原速率模型，实现高效还原和低碳炼铁。课题研究成果将有助于形成一套科学完整的复合铁酸钙矿物学理论及其还原理论。

It’s inevitable for the productivity and quality of sinter to be affected with the complication and diversification of iron ore resources. How to improve the reducibility, permeability of cohesive zone, utilization of bosh gas, and eventually reduce energy consumption and CO2 emission? This has become a key problem in blast furnace ironmaking field, and also become a social issue. In order to improve the sintering quality, it is necessary to focus on the bonding phase (basically sillico-ferrite of calcium and aluminum, shorten as SFCA). But the basic physical chemistry properties of SFCA have not been clear so far. Therefore, based on two priority areas in "13th Five-Year" development planning of the National Science Foundation of China, "low carbon ironmaking" and "key metallurgical thermodynamic data", the applicant hopes to focus on the SFCA from complicated sintering process, and investigate the basic physical chemistry properties of SFCA, including the crystal structure, synthesis methods, sintering characteristics, and reduction mechanism of SiO2-Fe2O3-CaO-Al2O3 system and its sub-system. Thermodynamical phase diagram analysis and kinetic model building will be used combined with modern measurement methods, so that the thermodynamic data on fluidity and surface tension of SFC can be determined, and the dominant phase diagram and reducing model of SFCA will be built. Then high-effective reduction and low-carbon ironmaking may be achieved. The investigation results of this project will form a set of scientific theory on mineralogy and reduction of SFCA.