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Data Description
| Data | Unit | Description | ||
| Set | Item | Type | Native | |
| Equipment Properties | Outlet air absolute humidity | Fraction or Percentage | Fraction | The kg water gas carried by one kg dry air. |
| Outlet pulp stream solids | Fraction or Percentage | Fraction | The solid fraction in the outlet pulp stream. | |
| Outlet air temperature | Temperature | F | The outlet air stream temperature. | |
| Outlet pulp temperature | Temperature | F | The outlet pulp stream temperature. | |
| Heat transfer efficiency | Fraction or Percentage | Fraction | The fraction of heat effectively transferred from the condensing steam. | |
| Steam pressure drop | Pressure drop | psi | The pressure drop from inlet steam to outlet steam. | |
| Blowtrough steam | Fraction or Percentage | Fraction | The fraction of steam that does not condensate. | |
Equipment Properties
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Example of using equipment
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Method&Equations
The Steam Dryer calculates the amount of water which will be evaporated to obtain outlet solid fraction
W = INFLO * (1 – INSF / OUSF)
where:
W is the amount of water that needs to be dried out from the inlet pulp stream
INFLO is the total inlet pulp stream mass flow
INSF is the inlet pulp stream solid fraction
OUSF is the outlet pulp stream desired solid fraction
The model back-calculates the amount of air needed to transport the water
AIRIN = W / (HOUT / HIN - 1) * 2 / HIN
where:
AIRIN is the amount of air required
HIN is the inlet air absolute humidity
HOUT is the outlet air absolute humidity
Next, the Steam Dryer calculates the quantity of heat required:
Q = (PENTHI - PENTHO) * INFLO + (AENTHI - AENTHO) * AIRINFLO
where:
Q is the heat required
PENTHI is the specific enthalpy of the inlet pulp stream
PENTHO is the specific enthalpy of the outlet pulp stream at the specified conditions
AENTHI is the specific enthalpy of the inlet air stream
AENTHO is the specific enthalpy of the outlet air steam at the specified conditions
The Steam dryer model back-calculates the amount of steam required as:
AMS = (Q / (ESTM - ESOUT)) / (1.0 - BLOW)
where:
AMS is the amount of steam required
ESTM is the enthalpy of the inlet steam
ESOUT is the enthalpy of steam at the outlet conditions you specified
BLOW is the blowtrough fraction
Warnings
Heat transfer efficiency fraction must be between 0.1 and 1. Calculations go on using the value 1.0!
The value for Blow-through Steam must be between 0 and 0.9. Calculations go on using the value 0.0!
Dryer pulp outlet temperature must be higher than 32°F, or 0°C!
Dryer pulp outlet temperature lower than pulp inlet temperature!
Dryer air outlet temperature must be higher than 32°F, or 0°C!
Ethanol - Water proportion in inlet pulp is higher than 0.1!
Cannot achieve given absolute humidity. Humidity was set to maximum!
Outlet air humidity is lower than inlet air humidity. Dryer calculations aborted!
