Nitrogen Gas Generators
Nitrogen gas generators can be used for the supply of nitrogen to glove boxes and desiccators. However, consideration must be given to the operating parameters of the equipment and the desirable results required in selecting this form of gas supply over traditional bottled, or boil-off nitrogen supplies.
Nitrogen generators rely on membrane separation of the constituent parts of air including moisture. Nitrogen emerges between 95 and 99% pure with an "at best" quoted "up to 99.99% pure".
For general laboratory use, including desiccators, this gas quality may well exceed or be within acceptable parameters, but for glove box use these percentages should be looked at more closely.
95% gas purity equates to 50,000 parts per million (ppm) oxygen, and even 99% is 10,000 ppm oxygen. As for the "at best" 99.99% pure, this equates to 100 ppm oxygen.
Bottled or boil-off nitrogen is typically 3 ppm oxygen and will provide an excellent supply quality for both open loop (gas purged) or closed loop (recirculated) glove boxes.
Where a Nitrogen gas generator is used, a gas-purged glove box will only provide an environment at best, somewhere below the system feed gas quality.
For recirculated glove boxes the gas feed will have to be fed directly into the gas purifier for an improved performance, and to avoid substantially degrading the contained environment each time the glove box is in demand of gas. The higher levels of oxygen will saturate the gas purifier more frequently.
Nitrogen gas generators fare somewhat better at moisture removal providing averagely a -60 to -65ºC dew point reading equating to between 5 and 10 ppm.
With the above reservations, Glove Box Technology Limited can design and supply nitrogen generator systems where the parameters are within specification.
Benefits include greater convenience and security of gas supply at a lower unit cost.
Please phone or email us if you have any questions, require further information or to request a quotation.