The many benefits of on site gas generation

Are you faced with the decision of whether to switch from purchasing bottled nitrogen or oxygen to on site gas generation? In that case, the decision is easy. You should!

Lower costs, the right purity, less transportation emissions, improved safety, no logistics headaches. In all of these areas, on site gas generation is the superior solution.

And making the switch is easy. All you need is a gas generator and a supply of compressed air.

But first, let’s take a look at how both options stack up in different areas.

On site gas generation and bottled gas – a scorecard

Costs: The costs of a cubic meter of gas generated on site is significantly lower than that of bottled or liquid gas. In addition, there is no need to enter into long-term contracts.

Purity: On site gas generation allows you to select the right gas purity for your application. Delivered nitrogen or oxygen are only available in a very high purity that most users don’t need.

Sustainability: Bottle or liquid gas deliveries come with significant transport emissions. On site generation eliminates those emissions. Pneumatech’s on-site generators further reduce your environmental footprint by minimizing your energy consumption.

Nitrogen supply control: Buying your oxygen or nitrogen means you are dependent on third parties. On-site generation gives you complete control and a continuous, reliable supply of your mission-critical industrial gas.

Logistics: The purchase of bottled oxygen or nitrogen poses various logistical challenges. Everything from ordering and receiving the bottles to storing and replacing them requires time and labor. And that’s if everything goes smoothly. On site gas generation removes all of these challenges.

Scalability: Are you planning to grow your business? An on site gas generator offers the required flexibility. 

Types of on site gas generators

If you want to produce your own oxygen, you need a pressure swing adsorption (PSA) generator. If you require nitrogen, you may also choose the membrane technology. Below you can find out more about their working principles, benefits and drawbacks.

Pressure swing adsorption (PSA): The nitrogen and oxygen in the compressed air are separated using adsorption. These generators consist of two separate pressure vessels. At any time, one of them is used to filter out the gas you need while the other is regenerating.

Membrane technology: A membrane filled with small, hollow polymer fibers is placed inside a cylindrical metal housing. Not all gases, vapors and contaminants pass through the membrane fiber wall with the same ease. This allows this process, which is called “permeation,” to separate the nitrogen from compressed air.

The PSA process allows you to produce nitrogen with a purity of up to 99.999% and oxygen with a purity of up to 95%. It requires less compressed air, which lowers operating costs. However, the intake air has to be very clean and dry, which means additional investments in air treatment. In addition, most applications don't require this level of purity.

The membrane technology might be for you if you don’t need extremely pure nitrogen. It can handle water vapor in the intake air, is quiet and takes up little space.

Membrane generators can produce a continuous flow of nitrogen while PSA units require additional external tanks to achieve the same flow. Another benefit is that membrane generators can be installed in a modular fashion. This makes it easier to scale up your nitrogen production.

An easy decision

If it is such an easy decision, why don't all industrial gas users make the switch or use an on site generator already?

The main reason is that many companies that would benefit from this technology are not aware of the advantages it offers. Many stick with what they know instead of embracing what might be best for them.

However, in some cases, the right solution is using bottled nitrogen or oxygen. This is especially true for operations with a limited demand of extremely pure gas.

To find out if you should make the switch, contact Ash Air and one of our experts will advise you.

Thanks to Pneumatech.com for this article.


Oxygen Generators

Pneumatech gives oxygen to your business. With the PPOG series, Pneumatech offers an attractive replacement for traditional oxygen supply with very interesting returns on investment.

The PPOG1-120 series uses Pressure Swing Adsorption technology to extract oxygen from compressed air, resulting in oxygen purity levels up to 95%.

The PPOG 2-18 HE series is a true game changer in on-site oxygen generation. 30% more efficient than traditional oxygen generators, the PPOG HE gives you the oxygen volume, purity and reliability you need at a massively reduced cost and a smaller environmental footprint.

PSA Oxygen Generators
With the PPOG series, Pneumatech offers an attractive replacement for traditional oxygen supply with very interesting returns on investment.

Nitrogen Generators

Discover the inner workings, versatile applications, and numerous benefits of an N2 generator. This revolutionary machine effectively separates nitrogen from compressed air, comprised of 78% N2 and 21% O2. A gas generator stands out as the easiest, most flexible, and economically viable method for securing your own nitrogen supply. Elevate your professional approach and embrace the efficiency and sustainability offered by on-site nitrogen generation, exclusively available in New Zealand.

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Who we are and how Ash Air can help your business!

Ash Air has been around in New Zealand since 1979, and we’ve grown into a nationwide company with international support and a reputation for quality and reliability.We look after all things compressed air for your business!

  • Reciprocating, Screw, air compressors
  • Vacuum pumps
  • Nitrogen
  • An extensive line of air treatment components

Ash Air's range of Chicago Pneumatic, Alup, Pneumatech, and Quincy compressors are used extensively around the world in industries ranging from oil and gas to food, automotive and farming, and we bring you these world class compressors here in the land of the long white cloud.Our technicians are compressed air equipment experts and are dedicated to addressing customer needs. Supported by a 13 locations nationwide, Ash Air offers one of the widest selections of compressed air equipment and parts available today in New Zealand.

Reliability and Efficiency

With Ash Air compressors, you can count on reliability and high performance for even the most demanding applications. We focus our efforts on the following:

  • Increasing uptime
  • Reducing unexpected repairs
  • Reducing energy consumption
  • Improving the cleanliness of compressed air


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