Method: Vary heat flux. Vary vaporizing temperature
(coolant side).
Process: Net vapor rate zero. Heat recovery into vaporizing
utility stream.
Advantages: Blow-down, if required, can be easily made
from drum.
Disadvantages: Extra drum required.
Application: Used with heat recovery by having condenser
reboil another tower or vaporize a utility stream (water to steam).
Most often used in systems with multiple parallel shells. Controlling
drum pressure affects all the condensers simultaneously.
Variants:
Configuration notes: Unusual.
Operation: Control valve varies pressure of vaporizing
stream on utility side of condenser. This in turn controls the
condenser LMTD.
Warnings:
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