View source for Evaporator

[[Category:Models]]
{{Navigation|[[Models]]|[[Models#Energy Transfer Models|Energy Transfer Models]]}}
{{Flash Cond HX header table|currentpage=2}}
'''Related Links:''' [[Solid-Liquid Separator]], [[Potash Evaporator]], [[Embedded Heat Exchanger (HX)|Embedded Heat Exchanger (part of Evaporator)]]  

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{{TOC}}
== General Description ==

{{Evaporator General Description}}

== Inputs and Outputs ==

{{Evaporator Input and Output}}

== Behaviour when Model is OFF ==

If the user disables the unit, by un-ticking the ''On'' tick box, then the following actions occur:
* All material in streams connected to the 'Feed' and 'Recycle' inlets will flow straight out of the 'Product' outlet, with no change in phase or energy exchange with material flowing through the internal heat exchanger;
* All material in streams connected to the 'Embedded HX Shell' connections will have no change in phase or energy exchange with material flowing through the Evaporator;
* No sub-models will be called.

So basically, the unit will be 'bypassed' without the user having to change any connections.

== Model Theory ==

{{Evaporator Model Theory|EvapCalcType=Solubility calculations}}

== Flow Chart ==

[[Image:Evaporator Flow Diagram Rev 1.jpg]]

== Data Sections ==

The default access window consists of several sections: 

# '''[[#Evaporator Page|Evaporator]]''' - The first tab contains general information relating to the unit and allows the user to set the Heat Exchange type and flows.
# '''[[#Results Page|Results]]''' - This tab contains the results fields for the Evaporator.
# '''[[#HX Page|HX]]''' - Optional tab, only visible if an Internal Heat Exchanger is selected. (In this case the Internal HX connections should be connected).
# '''[[Solid-Liquid Separator#Separ Page|Separ]]''' - Only visible if the Overflow stream is connected. The tab allows the user to specify the split between the Product and Overflow streams.
# '''[[Phase Change (PC)|PC]]''' - Optional tab, only visible if the Solubility is enabled in the Evaluation Block. 
# '''[[VLE]]''' - Always visible.
# '''[[RB]]''' - Optional tab, only visible if the Reactions are enabled in the Evaluation Block.
# '''[[EHX]]''' - Optional tab, only visible if the EnvironHX is enabled in the Evaluation Block.
# '''[[MU]]''' - Optional tab, or multiple tabs if more than 1 Makeup is selected.  Only visible if one of more Makeup is enabled in the Evaluation Block.
# '''[[Material Flow Section|QFeed]]''' - Optional tab, only visible if ''ShowQFeed'' is enabled. This page shows the properties of the mixed stream as the feed to the Evaporator.
#* This is before any Evaluation Block models are evaluated.
# '''[[Material Flow Section|QBodyFeed]]''' - Optional tab, only visible if ''ShowQBodyFeed'' is enabled. This page shows the properties of the mixed stream as the feed to the Body of the Evaporator.
#* This is before any Evaluation Block models are evaluated.
# '''[[Material Flow Section|QRecycle]]''' - Optional tab, only visible if ''ShowQRecycle'' is enabled. This page shows the properties of the recycle stream sent to the Embedded Heat Exchanger. This is only relevant if an Embedded Heat Exchanger (Heater or Cooler) is used.
#* This is AFTER the flash calculations, but before the split to slurry, overflow and vapour streams.
# '''[[Material Flow Section|QProd]]''' - Optional tab, only visible if ''ShowQProd'' is enabled. This page shows the properties of the Evaporator discharge as a single stream.
#* This is AFTER the flash calculations, but before the split to slurry, overflow and vapour streams.
# '''[[Common Data Sections#Common Data on Info Tab Page|Info]]''' tab - contains general settings for the unit and allows the user to include documentation about the unit and create Hyperlinks to external documents.
# '''[[Links Table|Links]]''' tab, contains a summary table for all the input and output streams. 
# '''[[Audit]]''' tab - contains summary information required for Mass and Energy balance. See [[Model Examples]] for enthalpy calculation Examples.

=== Evaporator Page ===

'''Unit Type: Evaporator''' - The first tab page in the access window will have this name.

{|   border="1" cellpadding="5" cellspacing="0" 
|width=200|'''Tag (Long/Short)'''||width=120|'''Input / Calc'''||'''Description/Calculated Variables / Options'''
{{Common Data on First Tab Page}}
|-
|  colspan="3" font style="background: #ebebeb"    | '''''Requirements'''''
|-
| On || Tickbox || This variable in used to turn the unit ON or OFF. If this not ticked, the material will flow out of the Product outlet with no change in state, i.e. the unit acts as a pipe.
|- 
| valign="top" rowspan="2" | Mode|| Stand Alone (Manual) || The Evaporator will act as a 'Stand Alone' unit and the user may set the required operating Pressure or Temperature.
|-
| Flash Train || The Evaporator will act as part of a '''[[Flash Train]]'''.  In this mode the Evaporator vent must be connected to a steam consumer, such as a [[Barometric Condenser]], [[Shell and Tube Heat Exchanger]], [[Shell and Tube Heat Exchanger 2]] or a [[Direct Contact Heater]].  The steam requirements of the steam consumer will drive the operating pressure of the Evaporator, therefore the user may NOT set the operating temperature or pressure. 
|-
{{OperatingP FlashTank | UnitOp=Evaporator}}
|- 
|TCorrection || font style="background: #ebebeb"   | Calc || 
|-
| UseFeedP || Tickbox || If this field is enabled then all of the Evaluation Block calculations will be performed at the Feed pressure.  Otherwise, if it is not enabled, the calculations will be performed at the final pressure.  See also [[#Model Theory|Model Theory]].
|-
|  colspan="3" font style="background: #ebebeb"    | '''''Feed Evaluation Block''''' 
{{EB Evaluation Data Section | Makeups = Yes | Reactions = Yes | EnvironHX = Yes  | Solubility = No | PhaseChange = No}}
|-
|  colspan="3" font style="background: #ebebeb"    | '''''Body Evaluation Block''''' 
{{EB Evaluation Data Section | VLE = Yes }}
{{Evaporator Vapour Entrainment and HX Options}}

=== Results Page ===
{{Evaporator Results Tab}}

=== HX Page ===

'''[[Embedded Heat Exchanger (HX)|HX]]''' - Optional tab, only visible if an Internal Heat Exchanger is selected. (In this case the Internal HX connections should be connected).
{{Embedded Heat Exchanger (HX) Data Section}}

=== Separ Page ===

{{Separ Table}}

== Adding this Model to a Project ==

{{Adding Model to a Project | DllName=HeatExchange | DllSubGroup=Heat Transfer | UnitOp=Evaporator | Group=Energy Transfer}}

== Hints and Comments ==

# There may be mass entering or leaving the unit via the [[Reaction Block (RB)|Reaction Block]] source or sink, so if the outgoing mass is not the same as the incoming mass, this may be a place to check first.
# The information in the [[Vapour Liquid Equilibrium (VLE)|VLE Section]] must be correct for the Evaporator to operate as required. If the VLE configuration requires information that is not available, then the flashing will not occur.

== Example Project ==

*[[Example_Potash_Projects#SOP_Example_Project|SOP Example Project]]
*[[Example_-_03UnitModels_Projects_2#Evaporator_Flash_Train_Project|Evaporator Flash Train Project]]
*[[Example_-_03UnitModels_Projects_1#Crystallisation_Project|Crystallisation Project]]
*[[Rare_Earths_Project|Rare Earths Project]]
*[[Example_-_03UnitModels_Projects_2#Mechanical_Vapour_Recompression_MVR_Example|Mechanical Vapour Recompression (MVR) Example]]