EVAPORATOR Russian patent published in 2004 - IPC

FIELD: concentration of crystallizing and scale-forming solutions; evaporation of aluminate solution in production of alumina. SUBSTANCE: proposed evaporator is provided with natural ventilation and extended boiling zone; it is also provided with separator, coaxial heating chamber with heating steam supply branch pipe and lower solution chamber, extended circulating tube and solution delivery and drain branch pipes. Novelty of invention consists in availability of jacket for part of circulating tube which has perforations, 6 to 15 mm in size; said jacket is provided with heating steam supply branch pipe located below inlet of circulating tube to separator by 3-6 m; heating steam supply branch pipe is provided with shut-off fittings; solution drain branch pipe is located below inlet of circulating tube to separator by 0.5- 1.5 diameter. Lower solution chamber may be made in form of inverted truncated cone and inlet of circulating tube to separator may be tangential. EFFECT: intensification of process; reduced usage of metal. 3 cl, 1 dwg