复合式干选机回收废钯催化剂的试验及数值模拟研究

发布时间：2018-07-09 17:17

本文选题：复合式干选机 + 废催化剂　；参考：《中国矿业大学》2017年硕士论文

【摘要】：石油重整废钯催化剂中含有较多贵金属钯,其品位比一般铂钯矿石中钯的品位高得多,从废催化剂中回收钯金属成本,不仅可以提高经济效益,还可以减小环境污染。复合式干选机具有不用水、无污染、处理量大、分选效率高等众多优点,这为废催化剂的预处理提供了一种新途径。根据前期探索试验、数值模拟结果以及物料性质,对复合式干选机的床面进行了优化,制造了开孔直径2mm,格条安装角度50°的新床面,并对废钯催化剂进行分选试验,试验结果显示,废催化剂中的棒状物料和球形物料可以有效分离,分选效率较高。在探索试验基础上,分析了分选床面上废催化剂颗粒的受力和运动行为,推导了沿X轴(水平面上与背板平行)方向上,颗粒向棒状物料出口运动的速度表达式。建立了远离背板区域内棒状颗粒和球形颗粒沿Z轴(水平面上与X轴垂直)方向的运动微分方程,以及背板区域内底层颗粒和表层颗粒沿Z轴方向的运动微分方程。利用DEM-CFD耦合的方法,模拟废催化剂颗粒的运动行为和分离规律。探究了分选床面上流场速度和压强的分布,结果表明,在分选稳定后,床面上形成了稳定的有利于物料松散的局部高速度区域和局部低速度区域。分析了不同性质的颗粒在分选床面上的运动分离规律,得到了不同形状和密度组合下,两种颗粒的速度和位移随时间的变化规律。其结果表明,不同形状的两种颗粒之间在不同的密度组合下都产生了明显的位移差,可以实现有效分离,密度对颗粒的运动产生了一定的影响;在相同形状下不同密度的两种颗粒之间的位移差很小,无法实现分离。进行了复合式干选机分选试验研究,探究了振幅、振动频率、气速和床面横向倾角对分选效率的影响。运用正交试验对各因素的协调作用进行分析,试验结果表明:在振幅3.25mm、振动频率35Hz、气速1m/s、横向倾角5°的操作参数组合下,得到最高的分选效率为99.32%。建立了分选效率与各影响因素之间数学关系模型的表达式,得出了各因素对分选效率的影响显著程度:振动频率D横向倾角C振幅A气速。
[Abstract]:There are more noble metal palladium in the waste palladium catalyst for petroleum reforming, and its grade is much higher than that in the ordinary platinum palladium ore. The cost of recovering palladium metal from the waste catalyst can not only increase the economic benefit but also reduce the environmental pollution. Compound dry separator has many advantages, such as no water, no pollution, large amount of treatment, high separation efficiency and so on, which provides a new way for pretreatment of waste catalyst. According to the preliminary exploration test, numerical simulation results and material properties, the bed surface of the composite dry separator was optimized. A new bed surface with opening diameter of 2 mm and an angle of 50 掳was fabricated, and the waste palladium catalyst was separated. The experimental results show that the rod and spherical materials in the waste catalyst can be separated effectively and the separation efficiency is high. On the basis of the experimental results, the force and motion behavior of the waste catalyst particles on the separation bed surface are analyzed. The velocity expression of the particles moving towards the outlet of the rod material along the X axis (parallel to the back plate on the horizontal plane) is derived. The differential equations of motion of rod-like particles and spherical particles along Z axis (vertical to X axis in horizontal plane) and the motion differential equations of bottom particles and surface particles in backplate region along Z axis are established. The movement behavior and separation law of waste catalyst particles were simulated by DEM-CFD coupling method. The distribution of flow field velocity and pressure on the separation bed surface is investigated. The results show that stable local high velocity region and local low velocity region are formed on the bed surface after separation stability. In this paper, the moving and separating laws of particles with different properties on the separation bed surface are analyzed, and the variation of velocity and displacement of the two particles with time under different shapes and densities are obtained. The results show that there are obvious displacements between two kinds of particles in different density combinations, which can be separated effectively, and the density has a certain effect on the movement of particles. Under the same shape, the displacement difference between two kinds of particles with different densities is very small and can not be separated. The effects of amplitude, vibration frequency, gas velocity and lateral inclination of bed surface on separation efficiency were investigated. The coordination effect of various factors is analyzed by orthogonal test. The results show that the highest separation efficiency is 99.32mm under the operating parameters of amplitude 3.25mm, vibration frequency 35Hz, gas velocity 1m / s, transverse inclination 5 掳. The mathematical model of the relationship between the separation efficiency and the influencing factors is established, and the remarkable degree of influence of each factor on the separation efficiency is obtained: the vibration frequency D transverse dip angle C amplitude A gas velocity.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD953

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