This document discusses evaporators, which are devices used to convert liquids into gases or vapors. It defines evaporation and vaporization and describes different types of evaporators classified by the fluid being evaporated or the evaporation method. The key components and working of evaporators are explained. Design considerations like heat transfer, mechanical aspects, and thermal calculations are covered. Applications in industries like food and pharmaceuticals are highlighted. The impact of COVID-19 on evaporator production and ways to upgrade existing evaporators are briefly discussed.

1. 2
EVAPORATORS
BY : VIDUSHI MITTAL

2. INTRODUCTION
An evaporator is a device in a
process used to turn the liquid
form of a chemical substance such
as water into its gaseous-
form/vapor. The liquid is
evaporated, or vaporized, into a
gas form of the targeted substance
in that process. They are also used
in crystallization.
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Fig1: EVAPORATOR

3. 4
Fig2: EVAPORATION
• Surface phenomenon
• Slow process
room
• Occurs at normal
temperature
• Not usuallyvisible
Fig3: VAPORIZATION
• Bulk phenomenon
• Fast process
to boiling
• Occurs according
point
• It is visual
Fig4: CRYSTALLIZATION
• Bulk phenomenon
• Can be slow orfast
• primary object is to get crystal
by evaporation.
• It is visual.

4. HISTORYOF
EVAPORATOR
• SMI
first
equipment was
used for
in
evaporation
Nevada(USA).
• This equipment was
invented by keeping
the fact in mind that
evaporation is similar
to the snow making
process
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Fig5: SMI EQUIPMENTSOLUTION

5. WORKING OF
EVAPORATOR
• Solution is fed into
evaporator.
• Passed across a heat source.
• Water in solution gets
converted into vapor.
• The evaporator consistof
four components.
1. Heat exchanger.
2. Vacuum.
3. Vapor separator.
4. Condenser.
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Fig6: WORKING OFEVAPORATOR

6. On basis of
fluid to be
evaporated
On basis of
method of
evaporation
CLASSIFICATION OF EVAPORATORS
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7. ON THE BASIS OF FLUIDTO BE
EVAPORATED
POWER PLANT
EVAPORATORS
MAKE UP
EVAPORATOR
HEAT
TRANSFER
EVAPORATOR
SALT WATER
EVAPORATOR
PROCESS
EVAPORATOR
CHEMICAL
EVAPORATORS
HORIZONTAL
TUBE
VERTICAL
TUBE
BASKET
VERTICA
L TUBE
LONG
VERTICAL
TUBE
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8. ON THE BASIS OF METHOD OF
EVAPORATION
SINGLE
EFFECT
EVAPORATOR
BATCH
EVAPORATOR
SEMI-BATCH
EVAPORATOR
CONTIONUOUS
EVAPORATOR
MULTIPLE
EFFECT
EVAPORATOR
FORWARD
FEED
BACKWARD
FEED
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9. GENERAL TYPES OF EVAPORATORS
SHORT TUBEVERTICAL
BASKETTYPEVERTICAL
LONG TUBEVERTICAL
FALLINGFILM
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10. SHORTTUBE
VERTICAL
EVAPORATOR
• Oldest, still used
in sugar industry.
built by
• First
Robert .
• Also called
standard
evaporator. 11
Fig7: SHORT TUBE VERTICALEVAPORATOR

11. BASKET-TYPE
VERTICAL
EVAPORATOR
• Used for the evaporation
of salting and scale
forming liquids .
• Construction is similar to
the standardevaporator.
• Heating surfaceis
removable.
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Fig8: BASKET-TYPEVERTICAL
EVAPORATOR

12. LONGTUBE
VERTICAL
• Most widely used natural
circulation evaporator.
• Also called LTV
evaporator.
• Higher heat transfer rate.
• Commonly used in
concentrating black liquor
in paper and pulp industry.
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Fig9: LAONG TUBEVERTICAL

13. FALLINGFILM
EVAPORATOR
• Largely used
concentration of fruit
for
juice
and heat sensitivematerial.
• Suitable for scale-forming
solution.
• Leading evaporator.
• Respond fast to feedquality
and heat sourcesupplied.
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Fig10: FALLING FILM EVAPORATOR

14. METHODS OF FEEDINGOF
EVAPORATORS
Fig11: FORWARD FEED
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Fig12: BACKWARD FEED

15. METHODS OF FEEDINGOF
EVAPORATORS
Fig13: MIXED FEED
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Fig14: PARALLELFEED

16. APPLICATIONS OF EVAPORATOR
•Commonly used in most industries that depend on a
constant supply of fluids orchemicals.
• Used to convert seawater intoclean water.
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• The food industry used evaporator to achieve product
consistency.
•Pharmaceutical companies use evaporator to remove
excess moisture from drugs.

17. CAPACITY
PERFORMANCE
OF
EVAPORATOR
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Number of kilogram of water vaporized per hour
ECONOMY
Number kilogram of water vaporized from all
the effects per kilogram of steam used.

18. • Viscosity of
solution
• Nature of
product
• Known
• Vapor
pressure
• Known
• calculated
• Tube
diameter
• Tube length
• Tube layout
Tube size,
arrangement
and a
materials
Heat transfer
coefficients
Selection of
suitable
evaporator
Boiling point
elevation
THERMAL/ PROCESS DESIGN CONSIDERATION
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19. Operating
temperature
and pressure
Design
temperature
and pressure
Maximum
allowable
working
pressure
Thermal
expansion
MECHANICAL DESIGN CONSIDERATION
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20. THERMAL
DESIGN
CALCULATION
• Initially temperature in each
effect is estimated.
• Calculate total amount of solvent
vaporized from feed and
product concentration and feed
flowrate.
• Redistribute the overall
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temperature drop among all
the effects
• Calculate enthalpy values and
heat transfer area for each effect
and compare them which should
comeequal
Fig15: THERMAL DESIGNCALCULATIONS

21. COVIDATTACK
ON
EVAPORATORS
• Directly affecting production
and demand
• Creating supply chain
• Market disruption
• Financial impact on firms and
financial markets
Fig16: GRAPHICAL REPRESENTATIONOF
CORONA EFFECT ON EVAPORATORS
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22. AREASFOR
UPGRADING
EXISTING
EVAPORATORS
• Economic effects of
improvement
• Fine tuning existing
evaporators
• Modifying auxiliaryhardware
• Major hardware
modifications
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Fig16: FUTURE AMMONIA REFRIGERATION SYSTEM