O&M Manual v2
Page 22
6.
PRINCIPLES OF OPERATION
The Nitrogen Generator uses state of the art technology to provide the end user with a reliable source of
nitrogen. An overview of the operation of the generator is given below.
The Nitrogen Generator is a two-bed adsorber system. The Nitrogen Generator consists of two adsorber
vessels filled with CMS, a valve assembly, air filters, main pressure regulator, and a product receiver tank.
Dry, compressed air (~78%nitrogen, 21% oxygen, <1% argon) at 100-150 psig / 6.9 bar g and normally 68 °F
/ 20 °C is passed through the air filters, which remove particles and oil vapor, and then through the air inlet
regulator (if supplied), which reduces the air to the final operating pressure. It is important to maintain the
inlet air at the correct pressure; otherwise, generator performance may deviate from design. Clean and dry air
is directed to one of the adsorber beds where oxygen and water vapor is adsorbed faster than nitrogen in the
pore structure of the CMS, thus increasing the nitrogen purity of the product gas stream to the desired level
(95 – 99.999% as required by customer). This product flows out of the top of the adsorber bed, through the
pureflow valve, and into the product receiver at a pressure slightly below the feed air pressure.
The pressure in the adsorber vessels is equalized after a pre-factory tuned time before the next cycle starts.
The beds switch roles; the first bed is purged while the second bed produces nitrogen product. The active bed
will remain on-line until just prior to becoming saturated with oxygen. When the cycle is completed, the
controller will exhaust the saturated bed, and pressurize the fresh adsorber bed. This allows a continuous flow
of nitrogen gas from the unit for as long as the unit is in operation.
Oxygen enriched waste gas is piped to the atmosphere through a silencer. This waste gas mixes with the
surrounding atmosphere and dissipates with no adverse effect.
Dry nitrogen product stream, with the specified max O
2
content, exits the adsorber vessels and is stored in a
common product receiver tank (optional). Nitrogen purity and flow rate can be checked before the nitrogen is
supplied to the consumer.
