Page 40 - Chemical process engineering design and economics

26 Chapter 1

Second Effect
Pump, P-4 Material Transfer
Evaporator, CS-2 Component Separation
Flash Drum, PS-3 Phase Separation
Barometric Condensers Component Separation
2 stages, CS-5, CS-6 & Phase Separation
Steam Jet Ejectors Material Transfer
2 stages, C-2, C-3 & Mixing

Third Effect Same as Second Effect
Crystallizer, CS-10 Seed crystals - 20 - 25% of Component Separation
the batch
Temperature - from
43 - 46 °C to 20 - 39 °C
Time - 2 days
Yield - 60% crystals

Conveyor, CV-1 Material Transfer
Centrifuge, PS-5 Product-14% H 2O Phase Separation
Conveyor, CV-2 Material Transfer
Rotary Dryer, CS-11 Component Separation

Conveyor, CV-3 Material Transfer
Bin, S-3 Storage
Melter, H-3 Energy Transfer

Pump, P-7 Material Transfer
Pressure Filter, PS-6 Phase Separation

The next two stages of evaporation are carried out in a vacuum produced by
a two-stage steam ejector. The water vapor from the phase separator is first con-
densed by direct contact with cold water in the barometric condensers, C-5 and
C-6. Each condenser contains a long pipe, where the condensate accumulates until
the static pressure becomes great enough for the water to flow out of the con-
denser. Effectively, the barometric condenser is a pump. The remaining water
vapor and non-condensable gases - from the gases dissolved in the feed solution,

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