Energy, Vol.185, 102-110, 2019
Energy efficiency improvement in electron beam purification of silicon by using graphite lining
Electron beam melting technology can remove volatile impurities from silicon very effectively. However, the strong cooling capacity of water-cooled copper crucible brings high energy consumption, which confines the wide application of this technology. As far as energy utilization is concerned one can see in this paper, the refining process of silicon is improved based on numerical simulation and experimental results. The energy efficiency is increased through using a graphite lining between silicon and the bottom of water-cooled copper crucible. The results show the addition of graphite lining is resulting in increased thermal resistance and the heat loss is reduced. Compared with traditional electron beam melting technology, the temperature of the melt pool is increased at the same power accelerating purification process. The experiment results show that refining cycle time for same amount of material can be reduced while keeping same purification efficiency. As a consequence, the energy consumption is reduced by 33%. (C) 2019 Elsevier Ltd. All rights reserved.