On earth, nitrogen is the most commonly found as a pure element. It makes up 78.1% of our atmosphere’s volume but only 19 parts per million within the earth’s crust (relatively small). Industrial compounds such as ammonia, organic nitrates, cyanides, nitric acid, and other compounds contain nitrogen as well. Due to the strength of the diatomic molecule N2, when converted to gaseous form, it releases large amounts of useful energy.
Nitrogen itself is highly versatile and is a constituent in many organic compounds. Items ranging from Kevlar to cyanoacrylate (used in superglue) are produced thanks to nitrogen. Not only these items, but nitrogen is also a constituent in every major pharmaceutical drug class. Some of the more well-known include antibiotics, blood pressure medication (nitroglycerin and nitroprusside), morphine, and even natural caffeine.
In order to produce vast quantities of nitrogen for industrial use, two methods are practiced. The first method is called fractional distillation. This energy-intensive method freezes the air until it reaches the liquid stage. It then separates the nitrogen from the other compounds present using differential boiling points. Though this method is energy-intensive, it produces the highest purity of nitrogen (99.9995 percent).
The second method of preparation can be performed in two ways. Semipermeable hollow fiber membrane filtration is the first and it uses tiny semipermeable hollow fiber tube filters to separate compounds in the air based on their speed and weight. This method is quick, uses less energy, but provides lower purity levels (90 to 99.9 percent). The second is pressure swing absorption (PSA) and is a much more involved process in comparison. During this process, carbon molecular sieves (CMS) are used to attract the nitrogen compound based on its molecular properties while separating it from the rest. PSA nitrogen generators can provide a purity level between 95 and 99.9995 percent.
- Blanketing Gas- Used to protect flammable or explosive solids and liquids from air contact. Can also be sued for protection chemicals, solids stored foods to protection from degradation of atmospheric oxygen.
- Sparging – Bubbling of nitrogen gas to remove unwanted volatile components in order to meet pollution reduction regulations.
- Liquid nitrogen- Used to freeze soft or tough objects in order to make their grinding/shredding/pulverization much easier.
- Cryogenic grinding- Similar to liquid nitrogen yet is used mainly on products such as finely ground pharmaceuticals, plastics, pigments, and tire shredding.
- Metals Manufacturing
- Shrink fitting- The inner part of a metal object is shrunk using liquid nitrogen so that it may more easily fit inside another object. Once it begins to warm up, it will expand and create a tight fit inside the object.
- Concrete cooling- liquid nitrogen is used to slow the curing process of the concrete during pouring, providing better curing properties.
- Roadway construction- Grounds can be frozen in wet or soft sedimentary environments such as underneath waterways during the construction of tunnels.
- Chemicals, Pharmaceuticals, and Petroleum
- Industrial Purge- Used by refineries, petrochemical plants, and marine tankers to purge equipment, tanks, and pipelines of hazardous gases and vapors.
- Reactor cooling- Cold nitrogen gas and catalysts are used in conjunction to cool reactors.
- Fracking- Liquid nitrogen is used during the gas well completion phase to “frac” natural gas-bearing rock formations.
- Pipeline propellant- Nitrogen can be used as an inert gas to push liquids through lines or to clear them out before a new material is sent through.
- Rubber and Plastics
- Flash and fins can be cleared off molded plastic using nitrogen in freezing techniques to make them much easier to remove through mechanical action.
- Food and Beverages
- Food Freezing- liquid nitrogen allows for flash freezing of food products which prevents the formation of ice crystals which would damage the products taste and aesthetic.
- Nitrogen can be used to protect against oxidization in items such as vegetable oil and wine by expelling the air trapped within and coating the top of the liquid in a protective surface.
- Modified atmosphere packaging (MAP) – Used by trucks in shipments of perishable goods to prevent oxidization, mold growth, insect infestation, and moisture migration.
- Health Care
- Used as a shielding gas to prevent oxidization or moisture absorption in some medicines.
- Freezing can be used to maintain blood samples, livestock semen, or viruses for vaccinations.
- Nitrogen can be used in cryo-surgery to destroy diseased tissue.
Galveston County hosts a vast network of pipelines running throughout the county in efforts to transport multitudes of gaseous products. These pipelines extend offshores and to our local ports to provide one of the most diverse ranges of chemical products in a concentrated area.