Filtration furnace for sepg. pure zinc from zinc-iron alloy - for reclaiming zinc from sludge obtd. in zinc bath during hot galvanising

摘要

A furnace has a combustion chamber surrounding a refractory crucible. The base of the crucible is formed by a perforated plate covered by a refractory filter fabric and resting in a stack of rings forming a chamber collecting the pure, molten Zn passing through the filter. The base of the chamber has an outlet hole provides with a stopper plug mounted on lever arms, so the plug can close or open the outlet hole. The lever arms are pref. provided with a hand knob screwed into a bush to move the stopper plug. A workbasket is pref. used to place a solid mixt. of Zn and a Zn-Fe alloy in the crucible. During the hot galvanising of steel parts, a Zn-Fe alloy with m.pt. ca. 540 deg.C solidifies and collects in the base of the Zn bath, from which it is periodically removed.