Method: Does not work.
Process: Net vapor rate zero.
Advantages: None.
Disadvantages: Does not work.
Application: None.
Variants: Combine the condensate and vapor bypass before
it enters the drum.
Configuration notes: This is an incorrectly configured
hot vapor bypass design. Instead of maintaining a liquid level
in the condenser, the condenser is allowed to fully drain into
the condensate drum.
Operation: Bypass rate is controlled in an attempt to control
pressure.
Warnings: The key here is no liquid level in the condenser
and no vapor product. With no liquid level in the condenser, liquid
leaving the condenser is only slightly subcooled, or not subcooled
at all. No heat removal is available to condense the vapor that
bypasses the condenser. With no subcooling in the liquid to condense
the bypassed vapor, it is impossible for this system to maintain
pressure. Pressure will float on the heat removal capacity of
the condenser regardless of control valve position.
Special Note: This method has some controversy. Some instances
have been reported as successes and others as failures . The author's
experience supports the 'does not work' conclusion and recommends
avoiding it.
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