High-Temperature Fluidized Bed Processing of Waste Electrical and Electronic Equipment (WEEE) as a Way to Recover Raw Materials

Abstract

This paper explores the effectiveness of metal recovery and values of gaseous emissions during thermal e-waste processing followed by magnetic separation. The thermal process of conversion of this kind of waste is difficult due to the uncertainty of the operation when compared to the processing of homogeneous materials. This is due to their complex and heterogeneous structure. The adoption of the fluidized bed reactor makes the process feasible, stabilizing it significantly and limiting emissions of harmful gases. Mobile cellphones were used as the raw input material of 450 g total mass. During the thermal transformation, the exhaust gases such as: CO, CO2, NOx, SO2, HCI, HBr, HCN, NH3, phenol, hydrocarbons, HF and COCI2 were analysed. The thermal treatment resulted in 333.6 g of solids in the fluidized bed. They were fragmented into grains smaller than 1 mm and 0.5 mm. The process of magnetic enrichment was used next on grains greater than 1 mm and smaller than 0.5 mm. The process was carried out using a neodymium magnet for particles >1 mm and a plate electromagnetic separator (powered by a three-phase current) together with a 1-disc tape-type separator, which was used for particles <1 mm. Such an approach resulted in the recovery of 81.9% of cobalt, 96.6% of iron and 99.2% of neodymium. The most efficient method of magnetic enriching (MS) proved to be the use of the electromagnetic plate separator.

Research on Tennis Motion Evaluation Method and System Based on Deep Learning

“…In order to clarify the sequence of skeletal joint features and further reflect the overall skeletal shape, human skeletal architecture is divided into three parts: right, middle, and left. e right part includes the right hand and right leg; the middle part is the torso; and the left part includes the left hand and left leg [12]. e topological structure of the human skeleton can be obtained by splicing the obtained bone joint features according to the three parts of right, middle, and left, and the obtained bone node matrix will also be arranged in this order.…”