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Dryer heats the pulp with high or medium pressure steam and dries it in draught.
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What do you want to see?
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Data Description
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Data |
Unit |
Description |
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Set |
Item |
Type |
Native |
| Equipment Properties |
Outlet air relative humidity |
Fraction or Percentage |
Fraction |
The fraction of the maximum 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. |
The Dryer calculates the amount of water that need to 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 / RHOUT / AIRHMAX
where:
AIRIN is the amount of air required
RHOUT is the outlet air relative humidity
AIRHMAX is the outlet air maximum absolute humidity at the given conditions
Next the Steam Dryer calculates the quantity of heat required:
Q = (PENTHI - PENTHO) * INFLO + (AENTHI - AENTHO) * AIRIN
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))
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
Zero water vapor! Air in not calculated!
Solution: Set greater outlet consistency.
Zero pulp flow entering!
Solution: Set a nonzero inlet flow.
Zero air flow entering!
Solution: Set a nonzero inlet flow.
Missing Stream(s)!
Solution: Check if all streams are connected to the equipment.
Division by zero!
Solution: Check the outlet consistency.
Warnings 