Nitrogen generator, nitrogen purification, PSA, membrane, air.

Nitrogen generator
Crystec Technology Trading GmbH

Nitrogen generators for the production of high purity nitrogen (N2) from air

Nitrogen is required for various industrial processes. The Haber-Bosch process for the synthesis of ammonia and the production of calcium cyanamide are the most important examples. The use as a protective gas or inert gas and thus the prevention of oxidation is also a common application. This is used to prevent fire, explosion, corrosion or unstable chemical syntheses. Nitrogen can either be purchased directly in gas containers, temporarily stored in nitrogen tanks or generated by a gas generator. The nitrogen generator is a good alternative to replace liquid, compressed nitrogen bought in bottles. The self-sufficient on-site purification of air to nitrogen offers several advantages:

In contrast to air separation according to Linde, which cools and liquefies gases by means of expansion, two different systems are used in our systems. These generate gaseous nitrogen at lower cost. We differentiate between pressure swing generators (PSA) and membrane generators.

PSA Nitrogen Generator

So-called Pressure Swing Adsorption (PSA) is used to remove oxygen and therefore separate nitrogen (N2) from the air. This is based on a physical process that makes use of the different adsorption properties of different gases at different pressure levels in order to separate them. Depending on the implementation, it is also possible to separate other gases such as carbon dioxide. Oxygen-affine materials such as carbon molecular sieves (CMS) are used to remove oxygen and generate high-purity nitrogen. The gas mixture (air) flows at a certain pressure into the molecular sieve designed for this application. Due to the stronger interaction of oxygen with the molecular sieve, it accumulates here. The second gas (nitrogen) on the other hand is not adsorbed and thus leaves the generator enriched. After the molecular sieve has reached its capacity limit, the gas flow is diverted to another molecular sieve. The first molecular sieve can be regenerated through pressure reduction using the associated significantly weaker interaction between the molecular sieve and oxygen. After this, it is available for purification, again. The system is controlled by a program logic control (PLC). This allows continuous purification to be achieved.

Nitrogen PSA-Gas-Generator (SinceGas)
  • Stable gas generation using a semi-continuous process
  • Fully automatic system
  • Small footprint and easy operation: The system is operated from the front.
  • The cracker is characterized by its low power consumption and operating costs.
  • Implementation and design can be adapted within certain limits according to customer requirements
  • Depending on the design, purities up to 99.9995% can be realized
  • Depending on the design a gas flow of 3-5500 N m3/h can be realized
  • Full CE Certification

Nitrogen generator PSA


Unlike pressure swing adsorption, a membrane generator uses polymer hollow fiber membranes to primarily remove oxygen from the gas flow. The separation of nitrogen and oxygen takes place in the membrane separators. These always consist of a bundle of the above-mentioned hollow fibers and are gathered in a cylindrical shell. Based on the selective pass through and therefore different strong interactions of the gases with the hollow fiber, these can be separated. Each gas has a characteristic penetration rate. So there exists "fast" gas like oxygen and "slow" gas like nitrogen. By applying a pressure difference between the compressed inlet gas and low pressures behind the membrane, dry compressed air is selectively transferred through the membrane wall. As nitrogen migrates along the inside of the fiber and thus can form a nitrogen-rich product stream, oxygen emerges quickly from the fiber again and can therefore be vented at atmospheric pressure.
A nitrogen membrane generator is always made up of several hollow fiber bundles and offers a simple solution for generating nitrogen gas.

Nitrogen-Membrane-Gas-Generator (SinceGas)
  • Stable gas generation using a continuous process
  • Small footprint, easy operation: Operation switch installed on front panel.
  • The cracker is characterized by its low power consumption and operating costs.
  • Almost no start-up times necessary
  • Implementation and design can be adapted within certain limits according to customer requirements
  • Depending on the design, purities of up to 99.9% will be realized
  • Depending on the design a gas flow of 3-5000 N m3/h can be realized
  • Full CE Certification

Nitrogen generator, Membrane generator

Comparison of PSA generator and nitrogen membrane generator

PSA-Generator Nitrogen-Membrane-Generator
  • very high purity up to 99.9995% easy to implement
  • high efficiency
  • short start-up time
  • moderate requirements for input gas
  • low maintenance costs
  • purity up to 99,9% possible
  • Purity depends on pressure and gas flow
  • very short start-up time of the generator
  • very low maintenance costs
  • low weight and space requirement

Applications for nitrogen generators

Our nitrogen generators are used in various industrial utilization. Depending on the area of application, we can adapt our generators individually to customer requirements.

➣ Automotive industry

In the automotive industry and for automotive suppliers, nitrogen is mainly required in form of inert gas for welding work. Here nitrogen is used as a so-called auxiliary substance.

➣ Lithium-ion battery industry

At the battery composition, the nitrogen requirement is comparatively low at around 150N m3/h. However, the purity requirements are over 99.9 %. At the production of the starting materials, the requirement is usually significantly higher. Our systems can also handle a particularly high purity of 99.9995%. Nitrogen is required for manufacturing lithium iron phosphate, ternary material systems, graphite anodes, carbon nanotubes or supercapacitors.

➣ Marine Industry

Large quantities of nitrogen are required for manufacturing ship parts for oil tankers or chemical tankers. Here purities between 95 and 99% are sufficient.

➣ Electronic industry

A high purity of over 99.99% is required in the production of electronic parts such as LEDs, diodes, capacitors, SMTs, electrical ceramics or the stacking of chips.

➣ Heat treatment

In the production of car parts, gears, tools, or fastening elements, in addition to pure nitrogen, gas mixtures with carbon monoxide (CO), carbon dioxide (CO2) or ammonia (NH3) are used. The gases are used as protective gas or inert gas for furnace applications. Here usually are high demands on the purity of the gases.

➣ Powder metallurgy

In powder metallurgy, gas mixtures with hydrogen and high purity are used to manufacture the various materials such as tungsten, magnesium, copper, iron or aluminum powder.

➣ Synthetic fibers

The manufacture of synthetic fibers requires high purities and large capacities of N2

➣ Cable industry

For the production of fire-resistant, aluminum-coated or copper-shielded cables, nitrogen gas with high purity is required

➣ Brazing industry

Pure nitrogen is used when brazing aluminum parts. Even the smallest impurities are a problem here. For this reason, our systems produce nitrogen with a purity of 99.9995%. Nitrogen is also required when brazing copper. Here mixtures of nitrogen and hydrogen are mostly used.

➣ Iron & steel industry

For steel and iron production, nitrogen or a nitrogen-hydrogen mixture of particularly high purity is used. These gases are required for manufacturing stainless steel, galvanized and cold-rolled sheet metal as well as silicon steel.

➣ Copper processing

The same requirements as to steel processing apply to the production of copper tubes, copper rods and copper strips. A backup system with liquid nitrogen is often required in both areas.

➣ Food

In food industry, nitrogen is used in the packaging, preservation and filling of beverages. Food also stays fresh longer. In this way, fruit, salad and vegetables can already be packed in the greenhouse, agricultural business or farm. Furthermore, the durability significantly longer when packing meat in the slaughterhouse and fish in the port under a protective gas atmosphere. Moderate purity of the gas is often sufficient here.

➣ Pharmaceutical industry

In the pharmaceutical industry, particularly high requirements apply to comply with legal standards. This is easily possible with our systems.

➣ Household Appliances Industry

For the production of devices such as air conditioning systems, refrigerators and air purifiers, nitrogen with various purities starting at 99% is used

➣ Oil & Gas Industry

In the oil and gas industry, many processing steps are only possible with nitrogen. These include processes that affect chlor-alkali compounds, coal, natural gas and other chemicals.

➣ Tungsten Molybdenum Industry

Both tungsten and molybdenum are characterized by a high density. To produce the powders made from this material, nitrogen with a purity of up to 99.999% is also required.

➣ Laser applications

A continuous supply of high-purity nitrogen is essential for laser cutting or other applications. Our generators can ensure a sufficiently high quality here.

Crystec will be pleased to engineer a cost effective system to satisfy your most demanding and exacting requirements.