Sodium hypophosphite evaporation process

Abstract

The invention discloses a sodium hypophosphite evaporation process. A sodium hypophosphite aqueous solution is evaporated by using a three-effect evaporation device. The process includes the followingconcrete process steps: sodium hypophosphite is added into a first-effect evaporator with an appropriate flow rate, secondary steam generated by evaporation is separated by a first-effect gas-liquidseparator in the first-effect evaporator and then enters a second-effect evaporator, the secondary steam generated in the second-effect evaporator is separated by a second-effect gas-liquid separator,enters a third-effect evaporator, is evaporated by the third-effect evaporator, is separated by a third-effect gas-liquid separator, enters a condenser for condensation and then is discharged; and aconcentrate of the first-effect gas-liquid separator is pumped into the third-effect evaporator through a first-effect discharging pump located at the bottom, a concentrate of the third-effect gas-liquid separator in the third-effect evaporator is pumped into the second-effect evaporator through a third-effect discharging pump located at the bottom, and a concentrate in the second-effect gas-liquid separator is pumped into a crystallization kettle through a second-effect discharging pump after reaching a prescribed concentration. The sodium hypophosphite evaporation process can realize continuous evaporation of the sodium hypophosphite and is simple in operation and stable in discharging concentration.

Description

technical field [0001] The invention relates to the technical field of chemical production, in particular to a sodium hypophosphite evaporation process. Background technique [0002] In the production process of sodium hypophosphite, it is necessary to evaporate the 25% mass concentration of sodium hypophosphite solution to 85% mass concentration, and then carry out cooling and crystallization. For a long time, the concentrated evaporation of liquid hypophosphorous acid sodium solution has been concentrated and evaporated using a single-effect evaporation process. The single-effect evaporation process has high energy consumption, large steam consumption, and intermittent operation, which is not conducive to the realization of automatic control and high production costs. Contents of the invention [0003] The technical problem mainly solved by the present invention is to provide a sodium hypophosphite evaporation process, which can realize continuous evaporation of sodium h...

AI Technical Summary

Problems solved by technology

For a long time, the concentration and evaporation of liquid hypophosphorous acid sodium solution has been concentrated and evaporated using a single-effect evaporation process. The single-effect evaporation process has high energy consumption, large steam consumption, and intermittent operation, which is not conducive to the realization of automatic control and high production costs.

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