METHOD OF PREPARING HIGH-PURITY METAL AND ROTARY COOLING MEMBER FOR USE IN APPARATUS THEREFOR

摘要

A metal having a high purity is prepared by immersing a hollow rotary cooling member in a molten metal containing eutectic impurities and rotating the cooling member while supplying a cooling fluid to the interior of the cooling member, whereby the high-purity metal is caused to crystallize out on a metal deposition area of the peripheral surface portion of the cooling member present under the surface of the molten metal, the metal deposition area being the peripheral surface of at least a part of the entire portion, present under the melt surface, of the member. When the purified metal is caused to crystallize out by rotating the cooling member, a flow of molten metal having a downward velocity component is produced in the vicinity of an upper part of the entire portion, present under the melt suface, of the cooling member.