In this day and age, compressed gas cylinders are used in research labs all over the world, and when installed and handled correctly, they are a safe and reliable gas source for all your gas chromatography needs. However, gas generators are marketed as the better option.
Thus, it is essential to take the time to consider whether gas generators are, in fact, the better solution for your needs.
This is particularly vital when it comes to gas chromatography (GC). To help answer this question, this article will outline ten key reasons why gas cylinders may be considered the optimum gas solution for your lab.
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The Drawbacks of Using Gas Generators for Gas Chromatography (GC)
Sufficient Volume of Gas
It must be noted that, in terms of the volume they can produce, gas generators have restricted flexibility. The volume of gas that will be required in the long and short-term therefore needs careful upfront thought when considering a generator as a supply option.
Typically, gas generators are designed around a specific analytical procedure; as the scope of the need grows and changes, more generators may have to be purchased. Gas cylinders, on the other hand, are adaptable enough to meet the ever-changing needs of a modern laboratory.
Only Nitrogen (N2) and Hydrogen (H2) are Supplied
As gas generators are only able to supply nitrogen (N2) and hydrogen (H2), it is still necessary to hold any other gases in cylinders onsite. Additionally, the ability to switch carrier gas is limited for prescribed methods, like environmental testing, given that most EPA procedures require helium as the carrier gas.
Maintenance Costs
It is important to recognize that gas generators are not always the “plug-and-play” option they are billed to be. Generators still need routine servicing and maintenance, despite the fact that they have recently improved in terms of reliability.
Spare parts, a separate service and maintenance package, along with emergency breakdown coverage must all be purchased by users to ensure that the purity of the gas criteria is upheld – and naturally, all of this raises the overall expense of operating the generator.
Capital Outlay
When it comes to choosing a gas supply, it is significantly cheaper to rent gas cylinders than purchase a gas generator outright, and for more niche projects or smaller labs, this can consume a significant portion of a budget.
The Energy Costs Needed to Run the Generator
Generators are power-hungry machines, and their electrical power consumption can sometimes be overlooked when companies are more aware than ever of their carbon impact and actively working to reduce it.
A single gas generator for use in GC consumes about 18 kWh of power per day, compared to a typical household that uses 8.5 – 10 kWh per day.
Right now, when power rates are at all-time highs, the cost of merely running a small benchtop generator could easily reach hundreds of pounds annually.
Excess Heat Output
The sheer amount of thermal energy emitted by gas generators is a vital but often-overlooked consideration of using gas generators.
Up to 1000 BTU/hour of heat may be produced by one benchtop hydrogen gas generator, which is equivalent to one to two industrial servers or a small radiator. Therefore, this heat makes air conditioning systems a necessity, incurring additional energy expenditures.
Bench Space
Bench space is at a premium in the modern lab, and every piece of apparatus and equipment needs to earn its place.
A gas generator takes up floor or bench space, whereas cylinders are relatively compact or can be externally installed in a lab with inlet lines. It could be argued that with cylinders as an alternative, a generator does not deserve its place on the bench in place of something more vital.
Due to their flexibility, cylinders can also adjust quickly to the shifting needs of a laboratory. However, as generators are often built to support a particular analytical procedure, buying more may be necessary if demand rises.
Requires Switching to Hydrogen (H2)
Another key factor to consider when choosing between gas cylinders and gas generators is that gas generators can only make H2 gas. It is, therefore, necessary to consider detector types or prescribed methods, given that not all equipment is well-suited to working with hydrogen as a carrier gas.
Users of certain detectors are not able to use a hydrogen generator as a gas source. These detectors include discharge detectors (PDD), pulsed discharge helium ionization detectors (PDDHID), and helium ionization detectors (HID).
Cylinders as a Backup
In case of a generator failure, it is both routine and good practice for users of gas generators to store cylinders onsite as a backup source. This means that all the benefits of eliminating cylinders from the lab are rendered largely redundant.
Indeed, any users of the opinion that the alleged convenience of gas generators will lead to the demise of cylinders have likely not considered the necessity of cylinders as a backup source of gas. Due to the genuine risk of generator failure, holding cylinders on site as a backup gas source is still strongly advised.
Carbon Footprint
As sustainability considerations rise to the forefront of many business practices, firms are increasingly aware of their carbon footprint and actively attempting to reduce it.
The electricity consumption of a generator must therefore be considered in any calculations when working out whether a new type of gas source will truly be more environmentally-friendly.
When it comes to the carbon footprint of gas cylinders, it is also essential to consider how production and transportation impact the organization’s green credentials.
Should Your Lab Choose Gas Cylinders Or Gas Generators?
With the significant upfront costs involved in acquiring a gas generator and the associated expenses of maintaining and running it in your lab, plus the environmental impacts, gas generators are not always the ideal solution for laboratories. As highlighted above, there are several reasons why cylinders, when maintained and used properly, are still the better option.
Air Products is proud to offer gas cylinders that are specific to the laboratory market needs. Ultra-high purity gas is delivered through their BIP® technology, which features an integrated purification system to remove any trace pollutants before they leave the cylinder.
The result is that users can enjoy a supply mode that is reliable, flexible, and without any hidden extra costs and are guaranteed to receive the lowest concentrations of contaminants, moisture, oxygen, and total hydrocarbons of any ultra-high purity gas.
Visit Air Products’ website to learn more about gas chromatography, the hidden costs of gas generators, and Air Products’ advanced BIP® UHP gas cylinders.
References and Further Reading
- https://www.airproducts.expert/uk/BIP/articles/generators
- https://www.airproducts.expert/uk/BIP/articles/gas-chromatography
This information has been sourced, reviewed and adapted from materials provided by Air Products PLC.
For more information on this source, please visit Air Products PLC.