Process for precipitating compounds from zinc metal baths by means of a hollow rotary body that can be driven about an axis and is dipped into the molten zinc

Abstract

A process and device are disclosed for precipitating solid compounds from the liquid zinc or liquid zinc-based alloys of a metal bath. According to the disclosed process, partial amounts of the metal phase containing the compound(s) are exposed to an acceleration higher than the acceleration due to gravity and at least partially dissociated thereby into fractions containing heavier and/or lighter components. The molten mass depleted of solid compounds is returned to the metal bath and the part of the molten mass enriched with the desired compounds is discharged. The disclosed device is substantially characterized in that a hollow rotary body ( ) is introduced into the molten mass ( ). The hollow rotary body ( ) can be driven about an axis and is fitted in the submerged or lower area with conveyor means ( ) which project into the cavity. In its discharge or upper area, the hollow rotary body ( ) is provided with at least one discharge opening ( ) for the depleted molten mass ( ) eccentrically arranged in its wall and with at least one further discharge opening ( ) for the liquid metal enriched with the desired compounds centrally arranged and/or eccentrically arranged on the discharge side. At least one of the upper molten mass discharge openings ( ) in the rotary body ( ) opens into a discharge area of a housing ( ) which at least partially surrounds the rotary body ( ).