CAJ | 학술논문

通过钒钛磁铁矿精矿直接还原实验，研究了不同还原剂和添加剂对还原过程金属铁颗粒长大的影响。提高还原温度能促进还原产物中金属铁颗粒的长大，金属铁颗粒中V含量也显著增加。与用无烟煤和褐煤还原产物相比，用烟煤还原产物中金属铁颗粒明显长大，这是由烟煤中高灰分含量所引起的。金属铁颗粒长大机理的研究表明：Na2 CO3和Na2 SiO3的熔点较低，且能破坏铁橄榄石和铁尖晶石的结构，并生成一些低熔点物质，而SiO2能与铁橄榄石形成低共熔混合物。这些低熔点物质都有助于改善金属铁相的扩散，从而促进金属铁颗粒长大。
통과범태자철광정광직접환원실험，연구료불동환원제화첨가제대환원과정금속철과립장대적영향。제고환원온도능촉진환원산물중금속철과립적장대，금속철과립중V함량야현저증가。여용무연매화갈매환원산물상비，용연매환원산물중금속철과립명현장대，저시유연매중고회분함량소인기적。금속철과립장대궤리적연구표명：Na2 CO3화Na2 SiO3적용점교저，차능파배철감람석화철첨정석적결구，병생성일사저용점물질，이SiO2능여철감람석형성저공용혼합물。저사저용점물질도유조우개선금속철상적확산，종이촉진금속철과립장대。
The effects of reductants and additives on the grain growth of metallic iron were investigated during the direct reduction of vanadium-bearing titanomagnetite concentrates. It is found that both the particle size and the vanadium content of metallic iron in re-duced samples considerably increases as the reduction temperature rises. In comparison with a reduced sample using anthracite or lig-nite as a reductant, the particle size of metallic iron in a reduced sample using bitumite as a reductant considerably increases. This may be attributed to the high ash content of bitumite. A further study on the mechanism of the grain growth of metallic iron shows that Na2 CO3 and Na2 SiO3 , with low melting points, decompose the structures of fayalite and hercynite and generate some low-melting-point phases, while SiO2 react with fayalite and form eutectic mixtures. These substances with low melting points can improve the diffusion of metallic iron in reduced samples and facilitate the grain growth of metallic iron.