Deriming ASU plant


Does anyone have information about deriming an Air Separation Unit (ASU)? What are the approximate operating conditions (temperatures, pressures , etc).


The purpose of deriming an ASU is to remove parts of Carbon dioxide, Water, and Hydrocarbons out of the whole unit. Therefore, it’s necessary that the temperature of the unit is brought above zero centigrade.

To do so, first all the liquid has to be dumped. Then, without producing cold by using expansion turbine, air is run through the unit.
It’s very important that the deriming of the plant is done slowly. 10 degrees per hour is the maximum.
During the deriming, the pressure in the unit will rise, and the process will ask for less air due to this. So it’s important to open as many way’s out to the atmosphere, this helps to control the pressure, and it allows you the derim all the parts of the plant.
Most important thing in deriming is that the whole deriming process is done slowly and evenly throughout the whole ASU.

Normally the manufacturer of the ASU supplies regulations how to derim the ASU.


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