Thin-walled aluminium waste remelting in circulation circuit with magnetodynamic pump

Abstract

Modern technologies for remelting thin-walled aluminium waste are considered, and a new method to implement such process is proposed. This made it possible to increase the yield of a suitable remelted product to 83% from the mass of the initial remelting portion. The main idea is to use indirect heating of the charge. This will allow to significantly reduce the irreversible loss of metal due to burning which can reach 60%. In the proposed process, solid waste is melted by overheated melt stream. The movement of such stream is provided by the action of electromagnetic field. For the practical implementation of the offered idea, there was used a magnetodynamic pump (MDP) designed in the Physico-Technological Institute of Metals and Alloys of National Academy of Sciences of Ukraine. The MDP has a significantly higher heat and power factor than electromagnetic pumps of travelling magnetic field which are often used in similar technologies. Mathematical model of the remelting process of aluminium thin-walled and fine charge due to convective heat transfer was developed. On the basis of this model, an engineering calculation of the specific process of remelting used aluminium cans in the liquid aluminium stream was also carried out. The obtained results were used at further conducting a full-scale experiment. There is designed and successfully practically tested the experimental two-chamber circulation circuit with MDP for remelting thin-walled aluminium waste. Recommendations for further development of the proposed process were formulated. Graphical abstract