摘要
为了清晰认识煤粉磁选行为的特性,选取矩形磁钢-锥形聚磁介质闭合磁系提供高梯度磁场环境,建立了煤粉干式磁选过程磁性颗粒动力学模型。基于二维离散元软件PFC2D,研究了干式磁分离过程磁性颗粒运动行为,考察了磁场强度、极距、比磁化率、锥角对颗粒运动轨迹中位移、速度、平均不平衡力的影响。结果表明:磁场强度、比磁化率越大,颗粒在磁场中受力越大,位移、速度变化越明显,有益于颗粒的磁力捕集;保持颗粒距锥尖相对距离l/2,极距越小,位移、速度变化趋势越大,越有利于磁性颗粒的吸附、系统的稳定;锥角为π/3时,颗粒所受磁场力最大,系统易达到平衡状态;锥角对系统影响最弱,比磁化率较极距、磁场强度对系统影响大。
In order to clearly understand the magnetic separation behavior of pulverized coal, a closed magnetic sys- tem, with the structure of a rectangular permanent magnet matched with conical magnetic matrix, was selected to pro- duce high gradient magnetic field. And the dynamic model of magnetic particle during dry magnetic separation of pul- verized coal was established. Viewing the magnetic panicle as discrete system, the research firstly studied the motion behavior of magnetic particle in dry magnetic separation, based on PFC2D （ Particle Flow Code in 2 Dimension） soft- ware. The influence behavior between the sorting parameters and magnetic particles trajectory parameters were also studied. Sorting parameters mainly included magnetic field intensity, pole distance, magnetic susceptibility and cone angle;the trajectory parameters mainly referred to the displacement, velocity, and mean unbalanced force. The results show that the magnetic field intensity and magnetic susceptibility are proportional to magnetic capture effect, the grea- ter of them, and the larger of total force, displacement, and velocity of magnetic particle. With the pole distance decrea- ses, the displacement and velocity have obvious changes ; also it＇ s more beneficial to the particle capture in l/2 of the -rr pole distance. Magnetic force of particle is maximum while cone angle is ^-, and the simulation system is accessible to a equilibrium state. The magnetic susceptibility has greater impact on the simulation system than pole distance and magnetic field intensity, while the cone angle has the weak impact. It is very important for industry application to make clear the effects on particle motion of pulverized coal in dry magnetic separation from panicle level using numerical simulation software PFC2D.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2013年第9期1668-1674,共7页
Journal of China Coal Society
基金
教育部高等学校博士学科点专项科研基金资助项目(20114116110005)
关键词
离散元
PFC2D
高梯度磁场
干式磁选
数值模拟
Key words ： discrete element method
PFC2D
high gradient magnetic field
dry magnetic separation
numerical simula-tion
