熱プラズマ溶解したシリケートガラスの蒸発挙動

抄録

Samples of 40 mass%SiO₂-40CaO-20Al₂O₃(Glass) and 36 mass%SiO₂-36CaO-18Al₂O₃-10Fe₂O₃(Fe-Glass) were melted by argon plasma arc, with iron rods used for arc ignition. A direct current transferred type plasma generator was used with an output power of 6 kW. During arc melting, the iron rod located in the centre of the molten glass was melted. During Glass melting, the oxygen partial pressure was kept constant in the chamber. On the other hand, during Fe-Glass melting, the oxygen partial pressure steeply increased in the initial stage and then gradually decreased. The chemical state of iron ion in Fe-Glass was changed from Fe³⁺ to Fe²⁺ rapidly. The evaporation rates from Glass and Fe-Glass were 3.8×10⁻⁷ kg/s and 2.0×10⁻⁷ kg/s, respectively. It has been concluded that the rate of evaporation from the molten glasses is affected by the oxygen partial pressure which is determined by the state of the iron oxides in the samples during the melting.