CaCl2对烧结矿RDI的影响
来源期刊：中南大学学报(自然科学版)1998年第3期
论文作者：杨华明 邱冠周 唐爱东
文章页码：28 - 31
关键词：CaCl2;烧结矿; RDI;断裂韧性;机理
Key words：CaCl2; sinter; RDI; fracture roughness; mechanism
摘 要：低温还原粉化率(RDI)是烧结矿冶金性能的一项重要指标,RDI的波动直接影响烧结矿的质量,以及高炉的操作和产量.生产实践证明,经CaCl2处理能显著降低烧结矿的RDI.研究表明,CaCl2主要是通过Cl-在烧结矿表面的化学吸附而产生作用.Cl-与赤铁矿中Fe-O键的电子效应而形成强烈的π键键合作用,增强了赤铁矿抵抗还原过程中应力变化的能力;同时由于Cl-的作用,提高了玻璃相的断裂韧性,减弱了玻璃相中的裂纹扩展和延伸,从而降低烧结矿的低温还原粉化率.本研究还确定了烧结矿综合断裂韧性与烧结矿RDI之间良好的对应关系.
Abstract: Reduction Degradation Index(RDI) is an important index of metallurgical properties of sinter.The variation of RDI has direct effects on sinter quality,furnace operation and output. Industrial application indicated that addition of CaCl2 could remarkably reduce sinter RDI . The results show that the effect of CaCl2 results from chemical adsorption of Cl-on sinter surface.Electrical effects between Cl- and Fe-O bond of hematite has caused intenseπbond forces, which enforce the resistance of hematite to stress change during the low-temperature reduction. Meanwhile Cl- improves the fracture roughness of glass phase, which weakens crack spread and extension, resulting in the decrease of sinter RDI.A better relation between RDI and composite fracture roughness of sinter is determined in the paper.
