Nitrogen makes up 78 percent of the atmosphere and is a nonflammable, colorless, odorless, and tasteless gas. Nitrogen is inert except at arc welding temperatures, where it will react with some metals, such as aluminum, magnesium, and titanium. Nitrogen is widely used in plasma and laser cutting. Tulsa Gas & Gear offers many different sizes of nitrogen cylinders ranging from 20 cubic feet to cryogenic bulk systems.
Nitrogen Physical Properties
|Molecular Weight (lb/mol)||28.01|
|Critical Temp. (°F)||-232.5|
|Critical Pressure (psia)||492.3|
|Boiling Point (°F)||-320.5
|Melting Point (°F)||-345.9
|Gas Density @ 70°F 1 atm (lb/ft3)||0.0725|
|Specific Volume @ 70°F 1 atm (ft3/lb)||13.80|
|Specific Heat @ 70°F (Btu/lbmol-°F)||6.97|
Safety Data Sheet PDF Link
Nitrogen Uses and Applications
WELDING AND FABRICATION
Nitrogen is used as a purge gas for welding and brazing to prevent atmospheric contamination from oxidation to the welds.
Nitrogen is used for pressure testing and leak detection. Nitrogen is good for this because it is inert, has a low atomic weight and low cost.
Laser cutting is a thermal machining process where the laser beam serves as a tool. Many laser cutting applications rely on non-reactive (inert) gases as the assist gas. Nitrogen is generally used when cutting stainless or aluminum in order to achieve excellent quality. Unlike oxygen, nitrogen serves as a shielding gas in light gauge material to stop the burning process and allow the laser to vaporize the material.
Nitrogen is used during the heat-treating process for metal. Any metal over 600 degrees Fahrenheit will oxidize if it comes into contact with oxygen. This causes the product to become discolored and weakened. That’s where nitrogen gas comes in. Heat treating facilities use nitrogen gas to purge the oxygen from the air.
Food and Beverage
Nitrogen is used in the food and beverage industry for many different applications. Nitrogen gas has long been used in the food packaging industry to help preserve the freshness, integrity, and quality of the delivered product. Food packaging types include bags, bottles, cans, boxes, plastic, and cardboard containers. It is used by food packagers because of its extremely cold temperatures used for fast freezing and chilling. Another reason that nitrogen gas is often used for food packaging is to provide a pressurized atmosphere that prevents package collapse. Using N2 gas in this way helps ensure that more delicate foods, such as chips and crackers, won’t get crushed in the bags where they’re stored.
Nitrogen is used by breweries as an alternative to CO2. Beers that are infused with nitrogen are often referred to the beer as a “Nitro Beer”. The difference between the two is vast, with the nitro beer taking on a creamy texture and more evenly distributed flavors while the CO2 beer is more aggressive on the tongue and aroma forward.
Nitrogen is a key nutrient for yeast growth and is necessary for the successful fermentation of grape juice and must into wine. Nitrogen compounds in juice, must, and wine affect not only the fermentation, but the clarification, aroma, and final chemical composition of the wine. For these reasons, the analysis of nitrogen in the wine making process is recommended for ensuring a quality wine.
Nitrogen is also being used by the coffee industry for “Nitro Coffee” by being infused into a coffee that is cold brewed and served straight from a tap, just like a cold beer.
Medical, Pharmaceuticals, Biotechnology, and Healthcare
Liquid Nitrogen is used in the healthcare industry for many applications including cryotherapy. A common use for it is by skin care professionals for removal of warts, moles, verruca’s, skin tags, and some skin cancers.
Whole-body cryotherapy has gained popularity in recent years and claims to reduce inflammation, cellulite, anxiety, headaches, and even depression. Early adopters include professional athletes, who traded ice baths for cryotherapy to help ease their aches and pains. Liquid nitrogen is used to achieve the subzero temperatures required.
Liquid Nitrogen is widely use in animal reproduction. Liquid Nitrogen in used to freeze semen for storage until artificial insemination takes place
Automotive manufacturing of electronic components consists of welded parts, heat treating elements, plastic extrusion, and safety systems. Nitrogen gas keeps upholstery from deteriorating, chemicals in the auto paint dry, and pressure in tires consistent. Passenger cars can also benefit from the more stable pressures. Humidity (water) is a Bad Thing to have inside a tire. Water, present as a vapor or even as a liquid in a tire, causes more of a pressure change with temperature swings than dry air does. It also promotes corrosion of the steel or aluminum rim. Nitrogen will keep your tire pressures more constant, saving you a bit in fuel and tire-maintenance costs.
Oil and Gas
Used both in onshore and offshore situations, applications for nitrogen include well stimulation, injection and pressure testing, Enhanced Oil Recovery (EOR), reservoir pressure maintenance, nitrogen floods and inert gas lift. Additionally, nitrogen can be used to help prevent flammable gases from igniting and protect tubulars from downhole corrosion. Nitrogen can also be used in pigging and purging a pipeline.
Nitrogen is important to the chemical industry. It is used to make fertilizers, nitric acid, nylon, dyes and explosives. To make these products, nitrogen must first be reacted with hydrogen to produce ammonia. This is done by the Haber process.
Nitrogen Purity Grades
|Product/Purity||Purity Percent||Part Number Prefix|
|Nitrogen: Research, 6.0||>99.9999%|
Oxygen < 0.5 ppm
Water < 0.2 ppm
Carbon Monoxide < 0.1 ppm
Carbon Dioxide < 0.1 ppm
Total Hydrocarbon (as CH4) < 0.1 ppm
|Nitrogen: Lab & Specialty Grade||>99.9995%|
Oxygen < 1 ppm
Water < 1 ppm
Total Hydrocarbon (as CH4) < 0.5 ppm
|Nitrogen: Ultra High Purity, 5.0||>99.999%|
Oxygen < 2 ppm
Water < 2 ppm
Total Hydrocarbon (as CH4) < 0.5 ppm
|Nitrogen: High Purity, 4.8||>99.998%|
Oxygen < 5ppm
Water < 3ppm
Total Hydrocarbon (as CH4) < 1 ppm
|Nitrogen: Industrial Grade||>99.998%|
Oxygen < 10 ppm
Water < 4 ppm
|Nitrogen: Food Grade||>99.0%|
Oxygen < 1%
Carbon Monoxide < 10 ppm
Carbon Dioxide < 300 ppm
Moisture < 55.8 ppm
|Medical Nitrogen: NF Grade||99.0%|
Oxygen < 1.0%
Carbon Monoxide < 0.001% (10 ppm)
Nitrogen Transportation Information
or Railcar Quantity
|2.2||75 kg or L||150 kg||N/A|
|2.2||75 kg or L||150 kg||N/A|
Nitrogen Conversion Chart
|cubic feet |
|cu meters |
|1 scf gas||0.07245||0.03286||1.0||0.02628||0.01074||0.04065|
|1 Nm3 gas||2.757||1.2506||38.04||1.0||0.4080||1.5443|
|1 gallon liquid||6.745||3.06||93.11||2.447||1.0||3.785|
|1 liter liquid||1.782||0.8083||24.60||0.6464||0.2642||1.0|
|1 short ton||2000||907.2||27605||725.4||296.2||1121|