鲕状赤铁矿深度还原物相及结构的演化规律
|
摘要
为了研究深度还原过程中鲕状赤铁矿石物相及结构的演化规律,采用X射线衍射(XRD)和扫描电子显微镜(SEM)考察了不同还原阶段还原样品的物相转化和微观结构变化,并建立了相应的深度还原机理和微观结构演化模型。结果表明,鲕状赤铁矿石深度还原过程中铁矿物按照Fe_2O_3→Fe_3O_4→FeO(Fe_2SiO_4,FeAl_2O_4)→Fe的顺序还原为金属铁,杂质组分则主要依据Fe-Al-Si-O→Fe-Ca-Al-Si-O→Ca-Al-Si-O的历程形成渣相;矿石鲕状结构按照由鲕粒边缘至鲕粒内部的空间顺序逐渐发生破坏,矿石微观结构演变过程可以分为边缘破坏、内部破坏、完全破坏3个阶段;金属相及渣相的形成与聚集生长是矿石微观结构破坏的直接动力。
In order to study the evolution law of the phase and microstructure of oolitic hematite ore during the coal-based reduction, the phase transformation and microstructure change of the reduced samples at different reduction stages were investigated by X-ray diffraction(XRD) and scanning electron microscopy(SEM), and the corresponding mechanism models of reduction process and microstructure evolution were established. The results show that the iron minerals are reduced to metallic iron in the order of Fe_2O_3→Fe_3O_4→FeO(Fe_2SiO_4, FeAl_2O_4)→Fe, and the impurity components follow the course of Fe-Al-Si-O→Fe-Ca-Al-Si-O→Ca-Al-Si-O to form slag phase. The oolitic texture of iron ore is gradually destroyed according to the spatial order from the edge to the interior of ooids. The process of microstructure evolution can be categorized into three stages:edge break, internal damage and complete destruction. The formation and aggregation growth of metal phase and slag phase are the direct driving force for the destruction of the ore microstructure.
In order to study the evolution law of the phase and microstructure of oolitic hematite ore during the coal-based reduction, the phase transformation and microstructure change of the reduced samples at different reduction stages were investigated by X-ray diffraction(XRD) and scanning electron microscopy(SEM), and the corresponding mechanism models of reduction process and microstructure evolution were established. The results show that the iron minerals are reduced to metallic iron in the order of Fe_2O_3→Fe_3O_4→FeO(Fe_2SiO_4, FeAl_2O_4)→Fe, and the impurity components follow the course of Fe-Al-Si-O→Fe-Ca-Al-Si-O→Ca-Al-Si-O to form slag phase. The oolitic texture of iron ore is gradually destroyed according to the spatial order from the edge to the interior of ooids. The process of microstructure evolution can be categorized into three stages:edge break, internal damage and complete destruction. The formation and aggregation growth of metal phase and slag phase are the direct driving force for the destruction of the ore microstructure.
引文
[1] 韩跃新,孙永升,李艳军,等.我国铁矿选矿最新进展[J].金属矿山,2015,44(2):1.(Han Y X,Sun Y S,Li Y J,et al.New development on mineral processing technology of iron ore resources in China[J].Metal Mine,2015,44(2):1.)
[2] Yu Y F,Qi C Y.Magnetizing roasting mechanism and effective ore dressing process for oolitic hematite ore[J].Journal of Wuhan University of Technology Materials Science Edition,2011,26(2):177.
[3] 栗艳锋,韩跃新,孙永升,等.物料形式对鲕状赤铁矿深度还原效果的影响[J].金属矿山,2016(12):32.(Li Y F,Han Y X,Sun Y S,et al.Effects of material status on indexes during coal-based reduction of oolitic hematite[J].Metal Mine,2016(12):32.)
[4] Novoselov K A,Belogub E V,Kotlyarov V A,et al. Mineralogical and geochemical features of oolitic ironstones from the Sinara-Techa Deposit,Kurgan District,Russia[J].Geology of Ore Deposits,2018,60(3):265.
[5] 孙永升,韩跃新,高鹏,等.高磷鲕状赤铁矿石工艺矿物学研究[J].东北大学学报:自然科学版,2013,34(12):1773.(Sun Y S,Han Y X,Gao P,et al.Study on process mineralogy of a high phosphorus oolitic hematite ore[J].Journal of Northeastern University:Natural Science,2013,34(12):1773.)
[6] 倪文,贾岩,徐承焱,等.难选鲕状赤铁矿深度还原-磁选实验研究[J].北京科技大学学报,2010,32(3):287.(Ni W,Jia Y,Xu C Y,et al.Beneficiation of unwieldy oolitic hematite by deep reduction and magnetic separation process[J].Journal of University of Science and Technology Beijing,2010,32(3):287.)
[7] Li Y F,Han Y X,Sun Y S,et al.Growth behavior and size characterization of metallic iron particles in coal-based reduction of oolitic hematite-coal composite briquettes[J]. Minerals,2015,8(5):1.
[8] Sun Y S,Han Y X,Gao P,et al.Recovery of iron from high phosphorus oolitic iron ore using coal-based reduction followed by magnetic separation[J].International Journal of Minerals,Metallurgy and Materials,2013,20(5):411.
[9] 徐洪军,师学峰,张颖异,等.高磷鲕状赤铁矿煤基直接还原实验[J].钢铁研究学报,2015,27(12):30.(Xu H J,Shi X F,Zhang Y Y,et al.Experiment of coal-based direct reduction of high phosphorus oolitic hematite[J].Journal of Iron and Steel Research,2015,27(12):30.)
[10] Han Y X,Li G F,Gao P,et al.Reduction behaviour of apatite in oolitic haematite ore using coal as a reductant[J].Ironmaking and Steelmaking,2016,44(4):287.
[11] Kou J,Sun T C,Tao D,et al.Coal-based direct reduction and magnetic separation of lump hematite ore[J].Minerals and Metallurgical Processing,2014,31(3):150.
[12] Bahgat M,Khedr M H.Reduction kinetics,magnetic behavior and morphological changes during reduction of magnetite single crystal[J].Materials Science and Engineering:Solid-State Materials for Advanced Technology,2007,138B(3):251.
[13] 胡兵,黄柱成,王兆才,等.氧化球团微波加热煤基直接还原过程微观机制[J].钢铁研究学报,2016,28(10):43.(Hu B,Huang Z C,Wang Z C,et al.Microscopic mechanism of oxidized pellets during coal-based direct reduction by microwave heating[J].Journal of Iron and Steel Research,2016,28(10):43.)
[14] Man Y,Feng J X,Chen Y M,et al.Mass loss and direct reduction characteristics of iron ore-coal composite pellet[J].Journal of Iron and Steel Research,International,2014,21(12):1090.
[15] Qu Y X,Yang Y X,Zou Z S,et al.Melting and reduction behaviour of individual fine hematite ore particles[J].ISIJ International,2015,55(1):149.
[16] Zhang Z L,Li Q,Zou Z S.Reduction properties of high alumina iron ore cold bonded pellet with CO-H2 mixtures[J].Ironmaking and Steelmaking,2014,41(8):561.
[17] Kowitwarangkul P,Babich A,Senk D.Reduction behavior of self-reducing pellet(SRP)for low height blast furnace[J].Steel Research International,2015,85(11):1501.
[18] Corbari R,Fruehan R J.Reduction of iron oxide fines to wustite with CO/CO2 gas of low reducing potential[J].Metallurgical and Materials Transactions,2010,41B(2):318.
[19] 布林朝克,郭婷.利用碳气化反应热力学的影响因素调控铁氧化物的碳热还原热力学[J].矿冶工程,2014,34(1):77.(Bu L C K,Guo T.Control of thermodynamics of carbothermic reduction of iron oxides by using factors impacting thermodynamics of carbon gasification[J].Ming and Metallurgical Engineering,2014,34(1):77.)
[20] 赵志龙,唐惠庆,郭占成,等.CO还原Fe2O3过程中金属铁析出的微观行为[J].钢铁研究学报,2012,24(11):23.(Zhao Z L,Tang H Q,Guo Z C,et al.Micro-behavior of the precipitation of metallic Fe in the reduction of Fe2O3 under CO atmosphere[J].Journal of Iron and Steel Research,2012,24(11):23.)
[2] Yu Y F,Qi C Y.Magnetizing roasting mechanism and effective ore dressing process for oolitic hematite ore[J].Journal of Wuhan University of Technology Materials Science Edition,2011,26(2):177.
[3] 栗艳锋,韩跃新,孙永升,等.物料形式对鲕状赤铁矿深度还原效果的影响[J].金属矿山,2016(12):32.(Li Y F,Han Y X,Sun Y S,et al.Effects of material status on indexes during coal-based reduction of oolitic hematite[J].Metal Mine,2016(12):32.)
[4] Novoselov K A,Belogub E V,Kotlyarov V A,et al. Mineralogical and geochemical features of oolitic ironstones from the Sinara-Techa Deposit,Kurgan District,Russia[J].Geology of Ore Deposits,2018,60(3):265.
[5] 孙永升,韩跃新,高鹏,等.高磷鲕状赤铁矿石工艺矿物学研究[J].东北大学学报:自然科学版,2013,34(12):1773.(Sun Y S,Han Y X,Gao P,et al.Study on process mineralogy of a high phosphorus oolitic hematite ore[J].Journal of Northeastern University:Natural Science,2013,34(12):1773.)
[6] 倪文,贾岩,徐承焱,等.难选鲕状赤铁矿深度还原-磁选实验研究[J].北京科技大学学报,2010,32(3):287.(Ni W,Jia Y,Xu C Y,et al.Beneficiation of unwieldy oolitic hematite by deep reduction and magnetic separation process[J].Journal of University of Science and Technology Beijing,2010,32(3):287.)
[7] Li Y F,Han Y X,Sun Y S,et al.Growth behavior and size characterization of metallic iron particles in coal-based reduction of oolitic hematite-coal composite briquettes[J]. Minerals,2015,8(5):1.
[8] Sun Y S,Han Y X,Gao P,et al.Recovery of iron from high phosphorus oolitic iron ore using coal-based reduction followed by magnetic separation[J].International Journal of Minerals,Metallurgy and Materials,2013,20(5):411.
[9] 徐洪军,师学峰,张颖异,等.高磷鲕状赤铁矿煤基直接还原实验[J].钢铁研究学报,2015,27(12):30.(Xu H J,Shi X F,Zhang Y Y,et al.Experiment of coal-based direct reduction of high phosphorus oolitic hematite[J].Journal of Iron and Steel Research,2015,27(12):30.)
[10] Han Y X,Li G F,Gao P,et al.Reduction behaviour of apatite in oolitic haematite ore using coal as a reductant[J].Ironmaking and Steelmaking,2016,44(4):287.
[11] Kou J,Sun T C,Tao D,et al.Coal-based direct reduction and magnetic separation of lump hematite ore[J].Minerals and Metallurgical Processing,2014,31(3):150.
[12] Bahgat M,Khedr M H.Reduction kinetics,magnetic behavior and morphological changes during reduction of magnetite single crystal[J].Materials Science and Engineering:Solid-State Materials for Advanced Technology,2007,138B(3):251.
[13] 胡兵,黄柱成,王兆才,等.氧化球团微波加热煤基直接还原过程微观机制[J].钢铁研究学报,2016,28(10):43.(Hu B,Huang Z C,Wang Z C,et al.Microscopic mechanism of oxidized pellets during coal-based direct reduction by microwave heating[J].Journal of Iron and Steel Research,2016,28(10):43.)
[14] Man Y,Feng J X,Chen Y M,et al.Mass loss and direct reduction characteristics of iron ore-coal composite pellet[J].Journal of Iron and Steel Research,International,2014,21(12):1090.
[15] Qu Y X,Yang Y X,Zou Z S,et al.Melting and reduction behaviour of individual fine hematite ore particles[J].ISIJ International,2015,55(1):149.
[16] Zhang Z L,Li Q,Zou Z S.Reduction properties of high alumina iron ore cold bonded pellet with CO-H2 mixtures[J].Ironmaking and Steelmaking,2014,41(8):561.
[17] Kowitwarangkul P,Babich A,Senk D.Reduction behavior of self-reducing pellet(SRP)for low height blast furnace[J].Steel Research International,2015,85(11):1501.
[18] Corbari R,Fruehan R J.Reduction of iron oxide fines to wustite with CO/CO2 gas of low reducing potential[J].Metallurgical and Materials Transactions,2010,41B(2):318.
[19] 布林朝克,郭婷.利用碳气化反应热力学的影响因素调控铁氧化物的碳热还原热力学[J].矿冶工程,2014,34(1):77.(Bu L C K,Guo T.Control of thermodynamics of carbothermic reduction of iron oxides by using factors impacting thermodynamics of carbon gasification[J].Ming and Metallurgical Engineering,2014,34(1):77.)
[20] 赵志龙,唐惠庆,郭占成,等.CO还原Fe2O3过程中金属铁析出的微观行为[J].钢铁研究学报,2012,24(11):23.(Zhao Z L,Tang H Q,Guo Z C,et al.Micro-behavior of the precipitation of metallic Fe in the reduction of Fe2O3 under CO atmosphere[J].Journal of Iron and Steel Research,2012,24(11):23.)