DEVICE FOR VACUUM DISTILLATION OF BISMUTH Russian patent published in 2011 - IPC C22B9/04 C22B30/06 

FIELD: metallurgy.

SUBSTANCE: device for vacuum distillation of bismuth consists of heated feeder, of evaporator with supply pipe, of condenser with discharge pipe and of receiver. The feeder and receiver are made in form of cylinders. Also, in a lower portion of the receiver there is made a recess. The feeder is equipped with three upper branches, while the receiver is equipped at least with two upper branches. The feeder and receiver are furnished with at least one lower branch for drain of melt of source bismuth and vat residue or distillate correspondingly. One of upper branches has a floating indicator of melt level. The supply pipe of the feeder is arranged coaxially relative to the branch of melt drain. Lower branches of the receiver and feeder are equipped with a device for periodic melt drain. An end of the supply part is sunk into the lower branch of the feeder, while the end of the discharge pipe is positioned in a lower point of the receiver recess. The evaporator and condenser are set with incline. All parts contacting melt of bismuth are made out of quartz glass. A gap between walls of branches of the feeder and receiver and corresponding pipes is 0.2-10 mm. The end of the drain pipe is located at height 0.1-300 mm from the lower point of the feeder. Internal diameter of the discharge pipe is 10-80 mm in the region of formation of free surface of melt.

EFFECT: lasting maintenance of mechanical strength of device, reduced instrument contamination of distilled bismuth, elimination of usage of additional reagents for restriction of contact of bismuth melt with air atmosphere; reduced summary weight of micro-drops of melt entrapped with bismuth vapours; pouring metal into moulds directly in process of distillation.

4 cl, 1 dwg