RU95102130A - Aluminate solution boiling out method and apparatus - Google Patents

Abstract

FIELD: alumina production. SUBSTANCE: method involves boiling out solution producing water-insoluble scale in the process of heating in one multiple-unit and supplying solution for self-evaporation from second evaporator in the course of vapor discharge; supplying scale-resistant solution into first unit and feeding it for separate self-evaporation. Apparatus has evaporators 2,7,15, heaters 1, self-evaporators 16 and additional solution self-evaporators 9 whose input is connected with second evaporator 7 through pipeline 8 and contact heaters 4,11. Input of contact heater 11 is connected with outer scale-resistant solution source and input of contact heater 4 is connected with pump 3 of third evaporator 7 and through slide with pump 19 and heater 20 is connected with unit 15. Simplified variant is not provided with pump 19 and heater 20. Change-over slides are arranged in front of heaters 4,11. EFFECT: increased efficiency, reduced aluminosilicate scaling, reduced consumption of vapor per ton of boiled out water and provision for self-cleaning by boiling out solution.

Claims (1)

The invention relates to the field of alumina production. A method and apparatus are proposed for countercurrent evaporation of a solution in tubular evaporators, which can significantly reduce the plant overgrowth with aluminosilicate, the specific steam consumption per tonne of evaporated water, and self-flushing with the evaporated solution due to the simultaneous evaporation of a solution in a multi-case unit that can form insoluble scale when heated in water, with its conclusion to self-evaporation from the second evaporator along the steam and the supply of a solution resistant to the release of such scale, in The first case with its conclusion to a separate self-evaporation. In the installation, including evaporators 2, 7 and 15, heaters 1 and self-evaporators 16, solution 9 self-evaporators are additionally installed, the input of which is connected by a pipe 8 to the second evaporator 7, and contact heaters 4 and 11, the input of one (11) is connected to an external a source of stable solution, and the inlet of the second (4) is connected to the pump 3 of the third evaporator, and the outputs are connected through the valve to the second evaporator 7 and through the valve to the pump 19, and the heater 20 to the apparatus 15. A simplified installation without pump 19 is presented and heater 20 with the location of the switching valves in front of the heaters 4 and 11.