GAS GENERATORS SYSTEMS

Gases are essential to the manufacturing industry, powering processes, creating specific atmospheres, and even becoming part of the final product. Overall, gases are indispensable to the manufacturing industry, playing a critical role in various processes and contributing to the production of countless goods.  

• Iron and Steel: Oxygen gas is used in furnaces to increase temperature and efficiency in steel production. Nitrogen gas is also used to prevent oxidation of metals, and argon gas is used in metal welding.
• Chemical: Gas is an important raw material in the production of various chemicals, such as natural gas used in the production of chemical fertilizers, hydrogen gas used in the ammonia production process, and chlorine gas used in the production of plastics and pesticides.
• Food and Beverage: Nitrogen gas is used to preserve food and maintain freshness, carbon dioxide gas is used in the production of carbonated drinks, and oxygen gas is used in wastewater treatment.
• Electronics: Nitrogen gas is used in the production of electronic components to prevent oxidation, and argon gas is used in the production of light bulbs.

Gases play a vital role in the operation of laboratories, with diverse applications ranging from energy sources and analytical processes to the maintenance of instruments and equipment.

• Inert Gases: Examples include argon (Ar), helium (He), and nitrogen (N2). These are used in processes requiring a chemically unreactive environment, such as welding, gas chromatography analysis, or chemical storage.
• Flammable Gases: Examples include hydrogen (H2) and acetylene (C2H2). These are used as fuel in certain instruments like atomic absorption spectroscopy or for creating flames in experiments.
• Oxidizing Gases: An example is oxygen (O2), used in combustion processes or in certain analytical instruments.
• Toxic Gases: Examples include carbon monoxide (CO) and chlorine (Cl2). These are used in specific research areas but require strict safety protocols.
• Other Gases: Examples include carbon dioxide (CO2), used in cell culture or for adjusting the pH of solutions.

The operating principles of each type of gas generator vary depending on the type of gas being produced and the technology used. Generally, the operating principles can be divided into three main categories:

Gas Separation from Air:

• Pressure Swing Adsorption (PSA):
  • Operating principle: Uses an adsorbent material, such as Carbon Molecular Sieve (CMS) or Zeolite, to capture other gases from the air under high pressure. When the pressure is reduced, the adsorbent releases the captured gas.
  • Applications: Used to produce high-purity nitrogen and oxygen.
• Membrane Separation:
  • Operating principle: Uses a membrane material with small pores to separate gases. Gases with smaller molecular sizes can pass through the membrane faster than gases with larger molecular sizes.
  • Applications: Used to produce medium-purity nitrogen.

Gas Production from Chemical Processes:

• Electrolysis of Water:
  • Operating principle: Uses an electric current to split water molecules (H2O) into hydrogen gas (H2) and oxygen gas (O2).
  • Applications: Used to produce high-purity hydrogen and oxygen.
• Biogas Production:
  • Operating principle: Uses the anaerobic digestion process to decompose organic matter by microorganisms in an oxygen-free environment, producing biogas, which mainly consists of methane gas (CH4).
  • Applications: Used to produce methane gas as fuel.

Gas Production by Cooling:

• Cryogenic Distillation:
  • Operating principle: Uses the difference in boiling points of each gas in the air to separate the gases. The air is cooled until it becomes liquid, and then the temperature is gradually increased to allow each gas to evaporate.
  • Applications: Used to produce very high-purity oxygen, nitrogen, and argon on a large industrial scale.”

Let’s be very clear: industrial gas of the highest purity isn’t the “best” gas. For example, nitrogen with a purity of 99.999% isn’t necessarily “better” than N₂ with a purity of 95%. It simply has a higher concentration of nitrogen compared to trace gases (mostly oxygen). The Application for which the gas is used will determine the purity it requires. For example: processes that involve the heating of metals (such as laser cutting and annealing) need a high nitrogen purity to prevent oxidation at rising temperatures. On the other hand, most blanketing applications only need 95-98% nitrogen purity to achieve their goal of avoiding fire and explosion. Using N₂ of a higher purity for blanketing will generate no additional benefits.

Why does this overspecification of gas purity matter? Because on-site gas generators give companies the freedom to produce their own oxygen or nitrogen with the right purity for their application. This in turn allows them to significantly lower their industrial gas costs, as producing lower purity gas requires less energy.

Purchased gas in cylinders, dewars or bulk deliveries, on the other hand, is always of the same high purity as a consequence of its cryogenic production process. That means that a large section of its users gets (and over-spends for) a high purity for which their application has no need.

Industrial gas quality refers to the presence of contaminants. These contaminants fall into three main categories: dust, water, and oil – as specified in the international ISO 8573-1 standard. Many industrial applications have specific ISO 8573-1 class requirements, which are more stringent for industries such as pharmaceuticals and food and beverage. Of course, subpar gas quality is a problem for every application, as contamination and corrosion can affect production systems and final products.

This means that gas can be of high purity, but not necessarily of high quality. It is one of the reasons why purchased gas comes in different industrial, foodgrade, and other qualities. Its high purity is fixed because of its production process, but its quality can be controlled more – which also comes at a cost.

On-site gas generators offer a higher quality as standard. Because they require clean inlet air to operate reliably and to protect their components, the nitrogen or oxygen they produce is also of high quality. For example, Atlas Copco nitrogen and oxygen generators comply by default with the very stringent ISO 8573-1 Class [1:2:1]. Additional filtration is available to allow very specialized applications to reach Class [1:1:0]. Here too, the highest quality will not benefit applications that don’t need it, while it does come with the extra cost of additional filtration. 

In the end, the goal is not to have gas with the highest purity and quality. It is about getting both right. Which means the Application is Key, as is the users’ gas and production system. Because the weakest link in the system will determine the purity and quality level that can be guaranteed. There’s no point generating gas of supreme quality if the network that distributes it is polluted. There’s no point in putting 99.999% purity nitrogen in a food container if the packaging material cannot retain that purity level.

While purchased gas offers limited flexibility in quality and hardly any in purity, on-site generation does allow users to set and achieve the gas purity and quality they need. This is an important reason why on-site generators generally offer the benefit of a lower price per unit of gas. Users can get the optimal mix of gas purity and quality to meet their production requirements with maximum cost efficiency.

Parker is the recognized leader in filtration, purification, and gas generation technology. Today, through a significant investment in research and development, Parker Lab Gas Generator products, including high-purity lab gas generators, have become the industry benchmark for quality and reliability. Moreover, all Parker lab gas generators meet NFPA 50A and OSHA 1910.103 regulations and are the first gas generators built to meet worldwide laboratory standards: CSA, UL, and IEC 61010.

Discover why our on-site generators are easy to use, safe, cost-effective, and provide reliable, consistent gas quality and pressure.