Many sites have excess LP steam, and one of the large users is the boiler feed water de-aerator. It can pay to increase de-aerator pressure which will then require more steam to raise the water to the higher steam saturation temperature.
De-aerator vents (for inert gas removal) are mostly fitted with manual valves. Rather than adjusting a valve, it may be preferable to use a gate valve with a hole drilled in the gate, sized to release the correct volume at the de -aerator design operating conditions. Invariably, with a manual valve, the vent rate is set conservatively high, sometimes excessively so. Modern de-aerator design should include a vent condenser to minimize the steam released along with the oxygen, nitrogen, CO2 etc.
Depending on energy cost, it may be economical to retrofit a vent condenser to existing de-aerators-typically an exchanger in the cold make-up water.
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