Industrial processes often require nitrogen during certain parts of the manufacturing process or to remove nitrogen from the product as it is undergoing the manufacturing process. Nitrogen compressors, also called nitrogen compressors address that need.
In this detailed buyer’s guide, we will look into what is a nitrogen compressor, which industries use nitrogen generators, the benefits, and drawbacks of nitrogen-based compressors.
Finally, we will look at the best nitrogen compressors suppliers and manufacturers.
What is a Nitrogen Compressor?
A nitrogen compressor, or more appropriately a nitrogen generator, is a class of compressors that can generate and then store under pressure various specific gasses in this case nitrogen.
Nitrogen generators have applications across many industries and applications, from food and beverage manufacturing to the automotive industry. The technologies used in nitrogen generators are usually two types
- Membrane Nitrogen Generators
- Pressure Swing Adsorption Generators
Each of these types of gas generation systems has its own advantages and disadvantages that make them appropriate for specific applications and industries.
Understanding the Technology
Nitrogen gas generators use two principles to produce the nitrogen that is then compressed and stored for later use. Each type of production system has advantages and disadvantages.
Different industries and applications apply these advantages and disadvantages to their specific needs. Before purchasing a nitrogen generator, it is critical to understand the method used to produce the nitrogen.
Depending on your needs, this can make a big difference in how you make your selection.
Membrane Nitrogen Generators
While the science behind a membrane nitrogen generator is complex, the concept is surprisingly simple. Membrane gas generators depend on the concept of gas permeability.
Gas permeability relates to the ability of different substances to allow specific gasses under pressure to pass through the substance that makes up the membrane while excluding other gasses.
If you imagine a bundle of tiny straws made of a gas permeable material into which compressed air is forced, you have the basic concept of a gas membrane system.
The gas-permeable straws allow only the specific gas to pass through the walls of the straw, where the system draws off and further compresses the gas.
In the case of nitrogen generators, the material only lets nitrogen gas molecules pass through the walls of the straws, scavenging it for later use.
The Advantages of Membrane Nitrogen Generators
Gas membrane separation technology has several advantages that make it attractive to industry.
- Simplicity of Operation – Gas membrane systems typically are easier to install and operate at lower pressures and ambient temperature unlike some other separation processes
- Smaller size – Modern membrane gas generators are smaller and more compact. These units are extremely efficient and require less electricity to operate
- Environmentally sound – Membrane technology doesn’t require any corrosive or polluting substances like other production systems.
- Suitable for continuous operation – Where the need for continuous operation is a factor, membrane technology is well suited
- No Moving Parts – The gas membrane system has no moving parts.
No moving parts make maintenance a minor concern for most systems and produce an efficient and economical model where the technology is appropriate.
The Disadvantages of Membrane Nitrogen Generators
There are some downsides to membrane technologies that may make using gas membrane separation unsuitable. Some of these disadvantages include:
- Purity issues – Gas membrane separation rarely produces pure products. There is almost always some contamination with other gases in the final product.
Where extremely pure nitrogen is required, gas membrane technology may not be appropriate.
- Air quality sensitivity – In some instances, the membrane may be susceptible to being compromised if the incoming compressed air contains contaminants that can attack the membrane.These compounds can cause early degradation of the membrane.
- The membranes are temperature sensitive – if the ambient temperature of the compressed air goes much above 100 degrees Celsius, the membranes can degrade and lose their gas selectivity properties.
- Fouling can be a problem – The small tubes of the membrane system ore subject to becoming contaminated if the compressed air fed into the system is not extremely clean.
Which Industries Use Nitrogen Generators?
Typically, membrane technology nitrogen generators are used where nitrogen purity in the 95% to 99% purity range is needed. These applications can include:
- Some laboratory uses – Where the laboratory process does not require nitrogen purity levels above 95%, membrane nitrogen generators are applicable.
- Food and beverage manufacturing and packaging applications – Manufacturing and packaging of many food products involve the use of nitrogen. Nitrogen is used in packaging to reduce the chance of spoilage and maintain the freshness of the product.
- Oil & Gas
The oil and gas industry are prime examples of this, and nitrogen membrane technology is often used to scavenge nitrogen and other gasses from the products during manufacturing.
- The aircraft industry, particularly in inflating aircraft tires – Most aircraft tires, especially those used on larger commercial planes, are inflated with nitrogen for several reasons.
The gas inhibits the deterioration in the tire and makes the inflated tire slightly lighter.
- The automobile industry where some tire companies are now inflating automobile tires with nitrogen – Some automobile manufacturers and tire shops are now inflating car tires with nitrogen to extend the life of the tires by reducing the effect of moisture and oxygen on the materials in the tires.
Pressure Swing Adsorption Gas Generation
The other major technology used in nitrogen gas generation systems is pressure swing adsorption gas generation. PSA systems are more complicated than gas permeable membrane systems but do have advantages of the membrane system ins specific applications.
Understanding the technology behind a PSA system is central to understanding these advantages.
In general, a PSA system is cyclic systems because they require purging at regular intervals. These PSA systems usually employ a process like this.
- Compressed air enters the bottom of one of two towers filled with a substance that acts as a sieve. This substance is usually a carbon-based material.
- As the air flows through the carbon molecular sieve (CMS), oxygen and the other gases present in the air are adsorbed by the CMS and the nitrogen passes on through the system and compressed for later use.
- At some point in the cycle, the system goes into a regenerative stage. The oxygen and other trace gases collected in the system are vented or purged from the system.
- The system then resets and begins the process of scavenging the oxygen and trace gases and allowing the nitrogen gas to pass through the system for collection.
This regeneration process is automatic and requires no intervention from the user except for changing filters, as the manufacturer’s recommended schedule indicates.
The Advantages of a PSA system
The great advantage of a PSA system for nitrogen gas generation is the purity of the product. A PSA system can generate nitrogen gas that is as much as 99.9995% pure. The other advantages of PSA systems include:
- Lower operating costs – PSA nitrogen generators offer much lower operational costs than most older technologies including the cost of bottled or liquified nitrogen
- Environmental impacts – The environmental impact of nitrogen gas generation using a PSA system is negligible. These PSA systems typically use less energy than the older system, such as cryogenic separation, and do not produce any greenhouse gases in the process.
- The purity factor – In practice, the purity levels produced by most PSA systems are in the range of 98.6% purity. Argon gas is most of the remaining gas. Argon is a more inert gas than nitrogen and is not a problem for most applications.
The Disadvantages of a PSA System
There are drawbacks to PSA systems to consider when deciding between a PSA system and a membrane system for your application.
- Initial System Costs – The upfront costs of a PSA nitrogen generation system may be higher than a membrane system. PSA systems are typically more complex and require more technology to operate.
- Operating Costs – The need to purge the system on a regular cycle demands control systems and operating components that need regular maintenance and scheduled replacement. These requirements add to the ongoing cost of operating a PSA system.
- Switch losses during the regenerative cycle – During the changeover portion of the purge cycle, unstable pressures in the system may create adsorption irregularities. Also, each cycle releases some of the nitrogen back into the atmosphere, making the system less efficient.
Where is PSA technology Applicable?
The use of PSA nitrogen gas generation systems applies where higher nitrogen purities are required.
These levels of purity are often called for in laboratory settings or in the manufacture of some products in a nitrogen atmosphere to prevent contamination with other volatile compounds.
These applications include:
- Laboratory processes and tests
- Fire protection systems
- Metallurgical processes
- Pharmaceutical industries
- Chemical and refining processes
The Players in the Nitrogen Generator Market
Almost all the significant manufacturers of air and gas handling systems have a line of gas membrane generators and compressors.
Among the more well known in the industry are
- The Titus Company – The Titus Company is a well-known member of the compressed air and gas system providers. The company was founded in 1986 and now does business worldwide.
Their product lines include. Titus builds both membrane and PSA nitrogen gas generators
- Compressed gas equipment including compressors, drier, chiller, coolers, dust collection and energy management
- Service and repair
- System analysis and design
- Installation and system monitoring
- Werther International – Werther international has been in business for over 40 years and now has three manufacturing locations and serves customers in 90 countries.
Werther specializes in compressor technologies and other automotive industry tools. Tin addition to nitrogen generation systems, Werther international produces
- A full range of compressors, including small handheld HP fractional compressors.
- ISO 9001 and ISO 124585 certifications
- Custom design and manufacturing for OEM requirements
- Unmatched customer service
- Atlas Copco – Atlas Copco is a world leader in many industrial applications. The Atlas Copco expertise in compressed gas technology is just one part of their worldwide group.
Focused on their customers, Atlas Copco has developed a concept that they term P.R.I.C.E. The PRICE concept refers to
- Purity Control – By allowing the user to control the purity level of the produced nitrogen, the customer also controls the cost associated with running the system.
Higher purity equals higher costs. By only producing the purity of nitrogen required, the customer controls the costs.
- Reduced Wastage – The Atlas Costco patented regeneration system captures the gas usually vented during the regeneration process and feeds it back into the system. Capturing these gases adds efficiency to the process, which equals a more profitable operation.
- Increased Safety – An in house nitrogen generation facility eliminates the dangers of moving and storing high-pressure cylinders as well as the elimination of delivery costs
- Cost Savings – Atlas Costco estimates that an in house nitrogen generation system results in savings of up to 89% on your nitrogen costs.
- Environment – By eliminating transportation requirements, the losses of gas during tank filling or cylinder changes, and the reduction of greenhouse gases due to transportation to your site, the environmental impact is greatly lessened.
- Terra Universal – Terra Universal is a manufacturer and distributor of laboratory equipment and environmental control systems. They get a mention here due to the portable, self-contained nitrogen generator.This unit is a complete system that is perfect in size of small laboratories, or other applications where the need for nitrogen varies from place to place yet doesn’t justify the cost of a large stationary unit and extensive piping to deliver the nitrogen to the point of use.
The features of this unit make it of interest to many end-users.
- Nitrogen purity up to 99%
- 59 DBA noise levels
- 6 SCFH flow rates
- No tanks or compressors needed
- Regulated pressure output
- Oil-free rocking piston compressor
- Conforms to all NSF-18 requirements
Your Needs Drive the Decision
In the end, it is your needs and requirements that drive the decision on which technology is best suited to provide your nitrogen needs.
Whether you are delivering clean, dry nitrogen to be used for tire inflation or performing laboratory testing requiring the highest purity possible, there are nitrogen generation systems that can meet your needs.
Understanding the technologies and the capabilities of these technologies is the key to making the best possible decision.