鉴于酒钢-1 mm镜铁矿粉矿采用常规选矿方法难以获得好的分选指标,进行常规磁化焙烧—弱磁选又需解决球团问题,以哈密烟煤为还原剂,对该粉矿开展了微波磁化焙烧—弱磁选研究,考察了煤粉用量、微波功率、焙烧温度、焙烧时间、焙烧产品磨...鉴于酒钢-1 mm镜铁矿粉矿采用常规选矿方法难以获得好的分选指标,进行常规磁化焙烧—弱磁选又需解决球团问题,以哈密烟煤为还原剂,对该粉矿开展了微波磁化焙烧—弱磁选研究,考察了煤粉用量、微波功率、焙烧温度、焙烧时间、焙烧产品磨矿细度和弱磁选磁场强度对所获铁精矿指标的影响。试验结果表明,在煤粉与矿石的质量比为5%、微波功率为1 k W、焙烧温度为550℃条件下将该粉矿微波磁化焙烧15 min,然后将焙烧矿磨细至-0.074 mm占85.65%,在92.16 k A/m磁场强度下进行1次磁选管选别,可获得铁精矿铁品位为55.10%、铁回收率为86.65%的较好指标,从而为该-1 mm镜铁矿粉矿中铁矿物的高效回收提供了一种新思路。展开更多
This study investigates the impact of mixing 0–1 mm fine coal with 0.15–0.3 mm magnetite powder to form a binary dense medium.The aim is to examine how the 0–1 mm fine coal influences the stability of vibration sep...This study investigates the impact of mixing 0–1 mm fine coal with 0.15–0.3 mm magnetite powder to form a binary dense medium.The aim is to examine how the 0–1 mm fine coal influences the stability of vibration separation in a fluidized bed and to achieve steady-state control of vibration fluidization.The vibration segregation behaviour of the binary dense medium under varying fine coal contents is analyzed in this work.The study discovers that the primary contributor to segregation is coal particles smaller than 0.5 mm.As the proportion of fine coal increases,upward movement becomes more pronounced,especially for particles smaller than 0.15 mm,where the upward segregation is most noticeable,with a peak mixing index of 8.06.The study confirms that the larger the particle size of fine coal,the higher the content limit for mixing with magnetite powder.According to studies on the process of fine coal segregation,coal particles larger than 0.5 mm move with the magnetite powder,and the mixing index remains below 3.Coal particles smaller than 0.5 mm fine coal will separate at a uniform speed in a stable environment produced by low vibration energy,with the top-level mixing index remaining constant at 26 after 6 min.Additionally,the study also examines how the fluidization of vibration separation is influenced by the segregation of 0–1 mm fine coal.The evidence shows that longitudinal density segregation within the binary dense medium competes with instantaneous density fluctuation.The longitudinal density distribution of the binary dense medium was found to be nearly uniform when the frequency was set to 25 Hz,amplitude to 2 mm,and upward gas velocity to 1.4 times the minimum fluidization velocity.The density fluctuation was found to be between 0 and 0.1 g/cm^(3).The best separation effect was achieved with fine coal particles ranging from 6 to 1 mm in size under these conditions.展开更多
文摘鉴于酒钢-1 mm镜铁矿粉矿采用常规选矿方法难以获得好的分选指标,进行常规磁化焙烧—弱磁选又需解决球团问题,以哈密烟煤为还原剂,对该粉矿开展了微波磁化焙烧—弱磁选研究,考察了煤粉用量、微波功率、焙烧温度、焙烧时间、焙烧产品磨矿细度和弱磁选磁场强度对所获铁精矿指标的影响。试验结果表明,在煤粉与矿石的质量比为5%、微波功率为1 k W、焙烧温度为550℃条件下将该粉矿微波磁化焙烧15 min,然后将焙烧矿磨细至-0.074 mm占85.65%,在92.16 k A/m磁场强度下进行1次磁选管选别,可获得铁精矿铁品位为55.10%、铁回收率为86.65%的较好指标,从而为该-1 mm镜铁矿粉矿中铁矿物的高效回收提供了一种新思路。
基金This work was supported by the National Natural Science Foundation of China(grant Nos.52474306,52220105008,52125403,52304306)Jiangsu Provincial Natural Science Foundation(grant No.BK20231073)Graduate Innovation Program Project of China University of Mining and Technology(grant No.2024WLJCRCZL100).
文摘This study investigates the impact of mixing 0–1 mm fine coal with 0.15–0.3 mm magnetite powder to form a binary dense medium.The aim is to examine how the 0–1 mm fine coal influences the stability of vibration separation in a fluidized bed and to achieve steady-state control of vibration fluidization.The vibration segregation behaviour of the binary dense medium under varying fine coal contents is analyzed in this work.The study discovers that the primary contributor to segregation is coal particles smaller than 0.5 mm.As the proportion of fine coal increases,upward movement becomes more pronounced,especially for particles smaller than 0.15 mm,where the upward segregation is most noticeable,with a peak mixing index of 8.06.The study confirms that the larger the particle size of fine coal,the higher the content limit for mixing with magnetite powder.According to studies on the process of fine coal segregation,coal particles larger than 0.5 mm move with the magnetite powder,and the mixing index remains below 3.Coal particles smaller than 0.5 mm fine coal will separate at a uniform speed in a stable environment produced by low vibration energy,with the top-level mixing index remaining constant at 26 after 6 min.Additionally,the study also examines how the fluidization of vibration separation is influenced by the segregation of 0–1 mm fine coal.The evidence shows that longitudinal density segregation within the binary dense medium competes with instantaneous density fluctuation.The longitudinal density distribution of the binary dense medium was found to be nearly uniform when the frequency was set to 25 Hz,amplitude to 2 mm,and upward gas velocity to 1.4 times the minimum fluidization velocity.The density fluctuation was found to be between 0 and 0.1 g/cm^(3).The best separation effect was achieved with fine coal particles ranging from 6 to 1 mm in size under these conditions.
