Nitrogen generators separate nitrogen molecules from the air to provide a pure, constant gas supply for your business. This type of gas is often used in various industries, like pharmaceuticals, food and beverage, packaging, chemical storage as well as materials processing.
Companies using this gas can choose from various generators to meet their needs. However, they commonly require to understand what purity level they need, the amount they want to produce and what delivery pressure they require downstream.
Nitrogen Generator Facts
Nitrogen gas is utilised in numerous industries for various processes. It displaces oxygen to extend food and beverage shelf lives, protect stainless and aluminised steel from corrosion, improves packaging, helps with purging electronic equipment/devices, and supports laser cutting applications.
Contrary to canisters, Dewar’s or liquid methods, a nitrogen generator system delivers continuous flows of the gas directly where you need it; eliminating supply issues due to tank running out. Furthermore, the purity of the nitrogen is higher since it’s produced on-site rather than transported in cylinders, providing more consistent gas supplies.
On-site nitrogen generation is a safer solution than using cylinders, as laboratory staff don’t need to lift heavy containers around. Furthermore, it saves money by eliminating the administrative hassle of ordering cylinders (raising purchase orders, scheduling deliveries and paying delivery fees) as well as fuel costs associated with transporting multiple sets of cylinders.
Membrane Separation: A membrane separation system utilises a single vessel that absorbs and removes oxygen from feed air. This requires minimal moving parts, minimising equipment footprint and saving significant installation and material costs.
Pressure Swing Adsorption: This technique requires additional controls, valves, adsorption beds and a refrigerated dryer as well as a nitrogen buffer tank. Due to these extra components, the system is significantly heavier and more expensive to install than its PSA counterpart.
In addition to adsorption, a PSA generator system is equipped with multiple stages of filtration before reaching the membrane. This eliminates particles in the feed air and prevents moisture from getting to the membrane, resulting in greater purity of gas generated.
On-site nitrogen generators are an on-demand gas supply solution that is ideal for time-critical applications. They offer many benefits over traditional supplies including lowered costs, consistent purity and less waste.
Nitrogen is used in a wide range of industrial applications such as metal fabrication, food preservation and petrochemical. In addition, it is also widely used in power generation and brewing.
Unlike membrane nitrogen generators, PSA nitrogen generators pass air through a carbon molecular sieve (CMS). The CMS only allows the smaller nitrogen molecules to pass through whilst larger oxygen and other molecules are adsorbed leaving high purity nitrogen.
On-site nitrogen generators can be sized and configured to meet a business’s specific needs for flow rate, purity and pressure. Commonly, these systems are available in cabinet and skid-mounted models. They include high-efficiency coalescing pre-filters and sterile grade after-filters.
PSA Nitrogen Generators
The most popular nitrogen generators in the UK come in two primary forms. One is a Pressure Swing Adsorption (PSA) nitrogen generator and the other utilises membrane technology.
A PSA nitrogen generator utilises a carbon molecular sieve (CMS) to separate oxygen from compressed air and generate pure nitrogen gas. Under high pressure, the CMS absorbs the oxygen, allowing the nitrogen gas to exit into a collection tank.
This generator is ideal for industries requiring high purity nitrogen or where there is a lower percentage of oxygen present in the feed air, such as pharmaceutical, food and beverage industries, among many others.
If your company needs a constant supply of nitrogen, it is often more cost-effective to generate your gas rather than purchasing it from a distributor. This can reduce costs and emissions and improve safety and operations.
PSA nitrogen generators use a process called Pressure Swing Adsorption to create nitrogen gas from clean compressed air. The process utilises a material called Carbon Molecular Sieve (CMS) to remove oxygen and particulates from the air.
The CMS material is surrounded by a layer of activated alumina to block any oxygen and particulates from reaching the nitrogen gas that’s produced. The adsorption cycle alternates between two adsorbent-adsorbent containing vessels to generate high-purity nitrogen.
PSA nitrogen generators are a good choice for industrial processes that require high-purity nitrogen, including chemical manufacturing, food processing and laboratory instrumentation. They also provide a reliable and consistent source of nitrogen that can last for years with minimal maintenance.
Membrane Nitrogen Generators
A membrane nitrogen generator works by pressing compressed air through hollow “straws” in the membrane that permit various levels of gas permeation depending on purity requirements. Each straw allows different percentages of oxygen to pass through and this cycle is repeated until your desired purity level is achieved.
These generators are an ideal option for facilities seeking a cost-effective design that can be quickly installed and removed. Plus, they run quietly while taking up minimal space.
Nitrogen generators are an ideal choice for laboratories that need to regularly blanket their atmosphere with oxygen to remove it. These systems can run continuously with minimal upkeep for decades.
The “fast” gases, such as oxygen, carbon dioxide and water vapour, pass quickly through the membrane wall while the “slow” nitrogen gas slows down as it tries to get past the pores. This process of selective permeation helps to separate nitrogen from the rest of the air, allowing it to be separated and delivered at high pressure.
Because of the passive nature of membrane nitrogen production, there are no moving parts to wear out or fail, which is an important benefit for many industrial applications. They also offer the flexibility to be installed in a modular fashion, allowing a facility to easily scale up or down their nitrogen gas production capacity as needed.