Research for the method of removing solid impurity from liquefied plastic waste using electrostatic force

在塑料垃圾回收系统中，塑料液化似乎是最合适的方法。然而，为了获得高质量的复制，必须从这种液化塑料中去除异物，如金属颗粒或碳化物质。本研究的目的是寻求一种利用静电力的去除方法。由于有必要了解固体颗粒在液化塑料中运动的基本特征，我们使用硅油和球形导电颗粒对该系统进行了模拟。检测了直径为1-2 mm的碳粒和钢粒。用视频显微镜观察粒子的运动并记录在录像带上。对浸泡在硅油中的平行板电极系统施加直流电场，使置于下电极上的颗粒带电，使颗粒所受的力成为库仑力和引力…之和更重要的是，当库仑力克服万有引力时，粒子朝上电极上升。粒子开始上升时的阈值电压与理论值一致。当外加电压高于阈值时，粒子呈现上下运动。观察到的有趣现象是，在电荷转移过程中，颗粒经常被滞留在电极上。对于碳颗粒，向上运动和向下运动的速度几乎相等。虽然钢质颗粒向上运动的速度比向下运动的速度慢，但随着外加电压的增加，两者之间的距离越来越近。颗粒停留在电极上的时间有很大的偏差。施加的电压越大，颗粒在电极上的停留时间越短，颗粒接触电极时，放电电流突然出现并逐渐减小。通过积分放电电流脉冲获得的粒子的电荷量随着施加电压的增加而增加。此外，还观察到了不同的运动模式，颗粒在电极边缘的上下运动呈曲线轨迹。这有可能通过改变电场的构型来控制粒子的运动。本研究将在这些实验知识的基础上，继续阐明粒子运动与电场构型之间的关系。较少

In a recycling system of plastic waste, liquefaction of plastics seems the most suitable method. However, the foreign substances, such as metal particles or carbonized material, must be removed from such liquefied plastics in order to get high quality reproduction. The purpose of this research is to seek a removing method by means of electrostatic force. Since it is necessary to know the fundamental characteristics of a solid particle motion within liquefied plastics, we have simulated this system by using silicone oil and a spherical conductive particle. Carbon and steel particles of 1 to 2 mm diameter are examined. The motion of the particle was observed and record in video tape with video microscope. The DC electric field is applied to a parallel plate electrode system which is immersed in silicone oil.The particle placed on the lower electrode is charged by the electric field, so that the force acting on the particle becomes the sum of the Coulombic force and the gravitational forc … More e. When the Coulombic force overcomes the gravitational force, the particle rises toward the upper electrode. The threshold voltage when the particle starts lifting agreed with the theoretical value. When the applied voltage is above the threshold the particle shows up-and-down motion. Interesting phenomenon observed is that the particle is often held on the electrode during the charge transferring. For carbon particles the velocities of upward and downward motion are almost equivalent. Although the velocity of upward motion for steel particle is slower than downward, they are getting closer with increase of the applied voltage. The elapsed time of a particle held on the electrode deviates extensively. The larger voltage is applied, the shorter the particle holding time on the electrode becomes.The discharge current arises abruptly when the particle contacts the electrode and decreases gradually. The charge amount of a particle, which is obtained by integrating the discharge current pulse, increases with the applied voltage. Furthermore, different motion pattern was observed, that the particle moves up and down showing curved trajectory at the edge of electrodes. This has the potentiality to control the particle motion by changing the configuration of electric field. The research will continue to clarify the relation between the particle motion and the electric field configuration on the base of the knowledge gained in these experiments. Less