Separation of metal laden waste using pulsating air dry material separator



Separation of metal laden solid wastes for their recycling utilization using passive pulsed air and active pulsing air classifiers was studied. Laboratory investigation showed that the active pulsing air separator performs more efficiently than the passive pulsed air separator due to the ability to accurately control operating parameters. By studying the difference of drag coefficients of the particles moving through the airflow of varying Reynolds numbers, models of the dynamic particle motion were developed and a computer simulation was prepared. Results of the simulation were reported to predict the observed results with artificial tracing spheres being separated by the laboratory equipment. Two different, real world feed materials were separated with the laboratory scale active pulsing air classifier. The discarded catalyst consisting of precious metal components and sintered magnetic beads was separated with the separation efficiency, of 97.6 %. The second real-world feed, electronic scrap crushed to a size of 0.5 to 2 mm, showed a separation efficiency of 92.41 %. At the same time, the grade of the recovered concentrate of metals was above 98 %.


Dynamic equation Electronic scraps Pulsating air Recycling Simulation 


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© Islamic Azad University 2011

Authors and Affiliations

  1. 1.School of Chemical Engineering and TechChina Univ. of Mining and TechXuzhou, JiangsuChina
  2. 2.College of EngineeringUniversity of KentuckyUSA

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