Low-flash gas heat exchanger
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Dear experts, why is it necessary to install a line for venting non-condensable gas in low-flash vapor heat exchangers? What is the reason? What kind of gas does \"non-condensable gas\" refer to here?
Low-pressure flash vaporization is the process in which water from the high-pressure flash tank is transferred to the low-pressure flash tank, where it undergoes secondary depressurized boiling to release non-condensable gases. Gases such as CO, H2, CO2, and H2S dissolved in the water are released through flash vaporization, while part of the water also flashes into steam. Therefore, after heat exchange and cooling, part or even all of the low-pressure flash steam condenses into water; however, CO, H2, CO2, and H2S in the flash steam do not condense into water, and these gases are known as non-condensable gases. If these non-condensable gases are not removed, they will accumulate in the heat exchanger, causing pressure buildup within it; this in turn leads to overheating and overpressure in the low-pressure flash tank