Some of the new-generation nitrogen generators use the APSA process to generate nitrogen. This APSA process relies on the fractionated distillation of air at very low (cryogenic) temperatures, and in only one column. In other words, APSA nitrogen generators are nitrogen generators that use cryogenic distillation of air to generate nitrogen.
After the air is being compressed, it is purified in the nitrogen generator, so that the cryogenic operation runs smoothly. The air is being compressed at around 9 bars with a centrifugal or a screw compressor and afterwards cooled down with the help of a cooling unit. Benefits of on site generators
The air that runs through the nitrogen generator must then be purified, so it passes through several filters and cooled down some more.
Afterwards the criogenic process must intervene, so the air enters a special area of the nitrogen generator, the cooling area, and then the oxygen in the air is separated from the nitrogen. At the bottom of the area there will be a liquid that is oxygen-rich and at the top the desired nitrogen.
The low temperature inside the nitrogen generator is maintained using a small quantity of liquid nitrogen, which is then added at the produced nitrogen.
This process is designed so that it’s all automatically controlled, it requires no manual procedures. If problems occur, the nitrogen generator is created so that it will try to solve them on its own.
For example, if the nitrogen consumption increases, a pressure regulator will maintain the normal pressure. Or, if the concentration of oxygen is too high, the APSA process is automatically closed and the excess of oxygen is ventilated outside. Furthermore, the nitrogen generator waits for the oxygen levels to decrease, and if they don’t, the whole system is shut down. When this occurs, the nitrogen generator takes safety precautions.