Electrostatic Separation of Copper and Glass Particles in Pretreated Automobile Shredder Residue

Beom-Uk Kim,Chul-Hyun Park

doi:10.3390/met8110879

Abstract

There is increasing demand for an efficient technique for separating automobile shredder residue (ASR) obtained from end-of-life vehicles (ELVs). A particular challenge is the physical separation of conductive materials from glass. In this study, the performance of pretreatment and induction electrostatic separation process was evaluated. The results show that a sieving/washing (combination of sieving and washing) pretreatment was the most effective for removing conductive material compared to electrostatic separation alone. The optimum separation efficiency of copper products was achieved with an applied voltage of 20 kV, a relative humidity of less than 35%, and a splitter position of 8 cm. Although the separation efficiency was slightly reduced when some small glass particles remained attached to the conductive materials, the separation efficiency of copper from the pretreated ASR dramatically increased to 83.1% grade and 90.4% recovery, compared to that of raw ASR (34.3% grade and 58.6% recovery). Based on these results, it was demonstrated that the proposed sieving/washing pretreatment was proficient at removing conductive materials from glass; thus, it has the potential to significantly improve the efficiency of electrostatic separation for ASR.

Highlights

End-of-life vehicles (ELVs) generally consist of 70–75% ferrous metal, 5% non-ferrous metal, and 20–25% Automobile shredder residue (ASR) is the waste produced when ELVs are shredded [1].At present, most automobile shredder residue (ASR) is landfilled; recent legislation, such as European Directive 2000/53/EC and the resource circulation law that has been in place in Korea since 2015, requires more than 95% of the ASR produced from ELVs to be recycled [2,3].Until now, research into mechanical/physical separation techniques for recycling ASR has primarily focused on the recovery of valuable materials using a variety of separation processes, such as electrostatic separation, eddy current separation, magnetic separation, sieving/heavy medium separation, etc. [1,4,5]
Conclusions and sieving/washing, were evaluated by electrostatic separation efficiency, of all the process, and sieving/washing, was werefound evaluated by electrostatic separation efficiency, and conductive of all the process, the the sieving/washing to be most effective for removing extraneous materials
The optimum of copper was achieved at an and applied of 20 kV, and sieving/washing, wereseparation evaluatedefficiency by electrostatic separation efficiency, of allvoltage the process, the tested, the optimum separation efficiency of copper was achieved at an applied voltage of 20 kV, relative humidity below

Summary

Introduction

End-of-life vehicles (ELVs) generally consist of 70–75% ferrous metal, 5% non-ferrous metal, and 20–25% Automobile shredder residue (ASR) is the waste produced when ELVs are shredded [1].At present, most ASR is landfilled; recent legislation, such as European Directive 2000/53/EC and the resource circulation law that has been in place in Korea since 2015, requires more than 95% of the ASR produced from ELVs to be recycled [2,3].Until now, research into mechanical/physical separation techniques for recycling ASR has primarily focused on the recovery of valuable materials using a variety of separation processes, such as electrostatic separation, eddy current separation, magnetic separation, sieving/heavy medium separation, etc. [1,4,5]. Research into mechanical/physical separation techniques for recycling ASR has primarily focused on the recovery of valuable materials using a variety of separation processes, such as electrostatic separation, eddy current separation, magnetic separation, sieving/heavy medium separation, etc. Researchers Santini et al reported that dense medium separation was superior to sieving by size when separating plastics from ASR prior to pyrolysis for increasing the yield of oil and gas. When pyrolysis was combined with a dense medium process, a conversion rate of over 90%

Methods

Results

Conclusion