Nitrogen Generation

Typical nitrogen gas supply methods include high-pressure cylinders, liquid mini tanks, or bulk storage vessels. However, each of these options introduces a range of problems that need to be solved. Then we can look at the benefits of nitrogen generation for many applications.

When considering nitrogen supplies, a reliable vendor must be outsourced and valuable space in or outside the company premises needs to be assigned for gas storage. Procedures must be established to monitor and manage the gas supply and arranging deliveries and payment must also be considered. Additionally, safety and handling concerns need to be considered. The cost of addressing these logistical issues can be high and difficult to forecast, while the price of gas and supplier rates change continually.

The environmental impact of truck-based deliveries is another important consideration for carbon footprint reduction. CompAir’s range of nitrogen gas generation systems offers ideal solutions enabling you to produce your total demand for food-grade nitrogen gas on your premises and under your control. This way, you can generate as much or as little nitrogen as you need, at a fraction of the cost of having gas delivered by an external supplier.

How is Nitrogen generated?

The range of nitrogen generators from CompAir uses pre-treated air from a standard industrial compressor which is essentially “sieved” so that oxygen and other trace gases are removed while nitrogen is allowed to pass through to the application. Air separation is not a new idea, but the levels of efficiency achieved by CompAir’s nitrogen generators are now higher than ever thanks to radical Pressure Swing Adsorption (PSA) designs and control systems that maximise gas output and reduce air consumption.

A nitrogen generation system can reduce costs by up to 90% when compared to traditional methods
of supply. If a company using liquid nitrogen was to convert to gas generation technology, the new
system could typically be expected to pay for itself in less than two years. For a company switching from cylinders, the payback period might even be one year or less.

Safer Alternative Solutions

The new systems can also make the workplace considerably safer for employees, eliminating the
safety risks of storing, handling, and changing heavy high-pressure cylinders. Whether or not you have an existing source of compressed air, CompAir provides all you need to set up your onsite nitrogen generation system and benefit from its ongoing, reliable operation.

Using high-quality compressed air to supply the nitrogen generators ensures long and trouble-free service and guarantees optimum performance. If you already have an existing compressor with spare capacity, we can help you develop a system around it. All our compressors are designed and manufactured to provide our customers with a reliable source of compressed air with low energy cost and high performance.

It is important that nitrogen generators are provided with the right quality compressed air. CompAir provides a wide range of purification products such as the coalescing filters and adsorptions dryers required to purify your compressed air to the levels required by your
nitrogen generator.

Main Benefits and Advantages of Nitrogen Generation

• High nitrogen purity: Pressure Swing Adsorption (PSA) nitrogen generator plants allow production of high-purity nitrogen from air, which membrane systems are unable to provide – up to 99.9% nitrogen.

• Dependence on outside suppliers: delivered gas is subject to price increases, rental agreements, long-term contracts, hazmat fees, inflexible delivery schedules, surcharges, and taxes as well as extra administrative work.

• Continuous supply: A nitrogen generator is designed to operate automatically on a 24/7 basis. There is no need to interrupt service to change tanks.

• Improved efficiency: A nitrogen system generates nitrogen at a pressure and flow rate required for the application, on demand, so no gas is wasted.

• Easy to install: Nitrogen generators, simply connect a standard compressed air line to the inlet of the nitrogen generator and connect the outlet to the nitrogen line.

What is a Nitrogen Generation plant?

A Nitrogen Generation Plant is a combination of equipment that allows the generation of Nitrogen.

A typical system includes a
• Compressor
• Cyclcone separators
• Air dryer
• Air receiver
• Pre-filters
• Micro filters
• Activated carbon filters
• Nitrogen generator
• Nitrogen buffer

These are some of the industries that use nitrogen

There are thousands of applications for industrial gases. Nitrogen is generally used for three main functions:
• It prevents microbial growth or acts as a filler gas in food applications
• It prevents slow oxidization of products such as chemicals and metals during processing or heating
• It prevents rapid oxidization of products that are flammable or explosive

Food and Beverage Industry

Most food products start to deteriorate from the moment they are harvested or prepared for packaging, being under attack from a multitude of spoilage mechanisms. By flushing, storing and/or packing with nitrogen, oxygen that many of these micro-organisms need in order to survive and multiply, is removed and the spoilage process is significantly reduced.

Prepared salads and vegetables, fresh chilled ready meals, meat, poultry, fish, dairy produce (including cheese), breads, coffee as well as snack foods such as potato chips and nuts can all benefit from ‘modified atmosphere packaging’ (or MAP as it is often referred to). By using nitrogen gas from a CompAir generator, the product shelf life is increased and the appearance and quite often taste, is also improved. Nitrogen is also used for ‘controlled atmosphere storage’ of fresh
fruits and vegetables, sparging and blanketing food oils as well as bulk powders, cereals, and liquid ingredients.

There are other Food & Beverage applications, including pneumatic conveying, automated filling or packaging lines, aeration to boost oxygen content, fermentation of wine, beer or yogurt, and PET bottle production, to name just a few.

Brewery Industry

Alcoholic and non-alcoholic drinks and ingredients can suffer similar spoilage mechanisms to food, however one of the most significant threats to product quality is oxidisation which adversely affects product taste. Beer and wine can absorb unwanted dissolved oxygen throughout the production process. Oxygen can also reduce the effectiveness of natural or added vitamin C which may be used in fruit juices. Nitrogen gas generators provide an ideal cost-effective solution for
all the processes involved in beverage production.

Blanketing of ingredients

Nitrogen is used to prevent contact of ingredients with air, thereby reducing the potential for oxygen uptake. During bulk storage, the use of sealed tanks means that positive nitrogen pressure can be used, ensuring that volume changes due to temperature fluctuations do not lead to the ingress of air. Nitrogen blanketing of atmospheric tanks is also possible, a small continuous flow ensuring that air cannot diffuse into the headspace through vents and compensating for volume changes. During emptying, the flow of nitrogen can be increased to fill the headspace and in sealed systems can be used to aid tank to tank transfer.

Clean in Place, (CIP), pipework and vessel purging

Caustic solutions containing sodium hydroxide are generally used in breweries to clean and sterilize pipework and vessels. It is beneficial to reuse the cleaning solution to reduce cost and wastage. If CO2 is used to drive the solution through the equipment to be cleaned, it can react with the sodium hydroxide to form sodium carbonate and sodium bicarbonate, reducing the cleaning and sterilising characteristics. This renders the solution unlikely to be suitable for re-use. Nitrogen does not react with sodium hydroxide maintaining its cleansing properties, facilitating reuse.

Reduced oxidation

Beer is quickly oxidised when exposed to air. If the quality of the product is to be ensured, then it needs to be constantly protected from air. The headspace of tanks can be filled with a protective layer of nitrogen gas to prevent air ingress.

Purging and filling

Equipment and pipelines are susceptible to oxygen pick-up. Nitrogen is an effective purging gas that enables brewers to reduce water consumption. Nitrogen assisted filling increases process speed, protects the beer from oxidation, and results in substantially reduced beer losses.

Pharmaceutical Industry

Whether in primary or secondary pharmaceutical product manufacture or as a centralised QA laboratory supply; within research establishments or universities and colleges, CompAir can offer a solution to suit the critical demands of this industry sector. For blanketing of pharmaceutical product ingredients and pressure transfer within reactor vessels, to micronising powders to prevent oxidisation or explosion, CompAir nitrogen generators can cut costs, reduce risk, and improve productivity. Centralised laboratory systems remove the need to have high pressure cylinders within the working environment and the possibility of running out of gas during a QA analysis procedure. CompAir nitrogen gas generators are typically used for analytical equipment such as LC/MS, GC, reaction blanketing within fume cupboards, solvent vaporation, ICP, ELSD, NMR and circular dichroism.

Metal Processing Industry

Laser Cutting

By far the largest use of nitrogen gas within this industry sector is for laser cutting. Nitrogen gas is used as an ‘assist gas’ to prevent oxidisation or discolouration and to blow away the molten material from the cut edge. It is also used in certain types of laser cutting machines as a ‘purge gas’ to ensure the laser beam guide path from the resonator (where the beam is generated), to the cutting head, is free of contamination that could otherwise affect the power or alter the shape of the beam.

Laser Sintering

Laser sintering or rapid prototyping uses a laser to form a solid 3D structure within a plastic powder material. Complex shapes and patterns can be constructed and modelled with ease. Nitrogen is used to blanket and prevent oxidisation of the powder material while it melts and solidifies to shape under the heat generated by the laser beam.

Laser Ablation

Nitrogen is used to expel fumes and blanket delicate electronic circuits where a laser beam is used to erode pathways on micro printed circuit boards.

Heat Treatment

In particular, the oxidisation of materials undergoing heat treatment, is a constant issue. Not only does it lead to an unwanted oxide layer of is colouration on the surface of the component, it can also effect the molecular properties of the material itself, altering both strength and durability.
Nitrogen is used throughout the heat treatment industry to exclude oxygen from the heat treatment process – in both furnaces and ovens. Nitrogen gas is commonly used to exclude oxygen from heat treatment furnaces and ovens. CompAir can supply nitrogen gas generation systems to replace expensive bulk vessel liquid supplies for many heat treatment processes.

Typical applications include:

• Belt furnaces
• Batch furnaces
• Vacuum ovens
• Brazing
• Carburising
• Tempering
• Annealing
• Gas quenching
• Neutral hardening
• Normalising
• Sintering

For more information on the nitrogen generation get in contact with our team.

For higher demand nitrogen onsite please use the following information.