Compressed air cool-drying - uses auxiliary heat exchanger transferring heat from incoming feed gas to emerging dried gas

摘要

Compressed air is cool-dried on passage through a system including a main heat exchanger through which coolant which in an extruded cooler is taken to low enough temp. for liq. or vapour in the compressed air to deposit as ice, to be subsequently removed. The main heat exchanger is preceded in the flow direction by an auxiliary exchanger coupled with the outlet gas system so that heat from incoming gas is transferred to emergency dried gas. The transfer is effected below the level at which incoming gas could be cooled sufficiently for ice formation. The auxiliary exchanger is of gas/gas type with an adjustable outlet feed rate. Alternativley a second auxiliary heat exchanger may precede employing as the coolant medium brine (which can also be used to the main heat exchanger. ADVANTAGE - Energy consumption in the main heat exchange zone is reduced, without harmful consequences elsewhere in the system.