关键词: 复杂难选铁矿石　, 工艺矿物学　, 磁铁矿　, 赤铁矿　, 嵌布特征

Abstract: The Qidong Miaochong Iron Ore Deposit,located in Hunan Province,China,is a significant iron ore deposit. The mineral distribution is characterized by a high degree of fineness,and the mineral associations are complex.The mineralogy of the ore is typical of high-silica,low-sulfur,medium-to-low phosphorus,and difficult-to-process low-grade iron ore.Conven tional beneficiation processes often encounter difficulties in achieving high recovery rates.In order to identify a rational separa tion strategy,this study systematically investigated the ore's chemical composition,mineralogy,particle size distribution,mineral embedding characteristics,and iron element occurrence state through chemical analysis,phase analysis,XRD,MLA,and optical microscopy.The results of the analysis indicate that the ore's TFe grade is 27.02%,with magnetite and hematite as the primary iron minerals at 19.55% and 13.14%,respectively.Gangue minerals are predominantly composed of quartz,potassium feld spar,and sodium feldspar. Iron minerals demonstrate fine grain sizes,with magnetite and hematite distribution rates reaching 58.77% and 72.11%,respectively,in the -0.03 mm size fraction.Dissociation rates remain low at 7.12% and 3.68%,re spectively,and both minerals are closely associated with quartz,exhibiting high intergrowth rates of 45.86% and 52.05%.Ad ditionally,magnetite frequently encloses fine-grained quartz and apatite,while hematite predominantly occurs as platy and fine grained inclusions,further complicating liberation. In light of these findings on process mineralogy,it is recommended that a combined magnetic separation and magnetic roasting process be employed,thereby providing a reference for the efficient utiliza tion of Qidong Miaochong iron ore.

Key words: complex refractory iron ore,process mineralogy,magnetite,hematite,embedded feature