Argon

Description Argon (Ar) is an inert gas that comprises 0.93 percent of the earth’s atmosphere.

Argon is Colorless, odorless, tasteless and nontoxic, argon forms no known chemical compounds. A specific gravity of 1.38 makes argon 25 percent heavier than air. At atmospheric pressure, it becomes a liquid at -302°F (-186°C). Non-corrosive and non-flammable, argon also exhibits low thermal conductivity and slight solubility in water.

Applications

Argon is used in diverse applications covering a number of industries, including:

• Aluminum to replace air or nitrogen, creating an inert atmosphere conducive to manufacturing aluminum; to assist in the removal of unwanted soluble gases during degasification; and to remove dissolved hydrogen and particulates from molten aluminum.
• Steel to displace gas or vapors and prevent oxidation during processing; to obtain temperature consistency and homogenous composition by stirring molten steel; to assist in the removal of unwanted soluble gases during degasification; as a carrier gas, to determine the composition of a sample through gas chromatography; and to flush out carbon monoxide and reduce chromium losses in the Argon-Oxygen Decarburization (A.O.D.) used during stainless steel refining.
• Metal Fabrication to create an inert gas shield during welding; to provide an oxygen- and nitrogen- free environment for annealing and rolling metals and alloys; and to flush molten metals to eliminate porosity in castings.
• Electronics to provide a protective atmosphere and heat-transfer medium for growing germanium and silicon crystals for ultra-pure semiconductors.
• Lighting to fill incandescent and fluorescent light bulbs; to create a blue light in neon-type lamps.
• Windows and Doors Because of its low thermal conductivity, argon provides window manufacturers with the gas barrier they need to produce double-pane insulated windows. During the production process, argon gas is injected between two window panes. This insulation barrier greatly improves the window’s energy efficiency.

Supply Options

USW offers its customers a variety of argon supply options including:

• Bulk liquid delivery in cryogenic tanker trucks
• Bulk gas delivery in high pressure tube trailers
• Portable liquid cylinders
• High pressure gas cylinders

 

Nitrogen

Description Nitrogen, or N₂, is a diatomic gas which comprises 78 percent of the earth’s atmosphere. In addition to air, nitrogen is found in the protein matter of all life forms, in some natural gas-hydrocarbon deposits, and in many organic and inorganic compounds.

Colorless, odorless, tasteless, and nontoxic, nitrogen exists as a non-flammable gas at atmospheric temperatures and pressures. A specific gravity of .9669 makes nitrogen slightly lighter than air. When cooled to its boiling point of -320°F, nitrogen becomes a colorless liquid which can, in turn, be compressed into a colorless, crystalline solid. It is only slightly soluble in water and most other liquids, and is a poor conductor of heat and electricity.

Most uses of gaseous nitrogen depend on its inert characteristics. At high temperatures and pressures, however, it will combine with some reactive metals (such as lithium and magnesium) to form nitrides, as well as with some gaseous elements such as hydrogen and oxygen.

Applications

• Chemical Processing to inert vessels and oxygen-sensitive chemicals, creating an oxygen-deficient environment that reduces safety hazards; to propel liquids through pipelines; and to manufacture ammonia.
• Food to extend shelf-life in packaged foods by preventing spoilage from oxidation, mold growth, moisture migration and insect infestation; to rapidly freeze; and to refrigerate perishables during transport.
• Petroleum Recovery and Refining to improve recovery and maintain pressure in oil and gas reservoirs; to blanket storage tanks and product loading/unloading; to purge pipelines; and to strip volatile organic compounds (VOCs) from waste streams or to cool vent streams. Controlling VOC emissions helps refiners comply with U.S. Clean Air Act requirements.
• Metal Production and Fabrication to protect metals such as steel, copper and aluminum during annealing, carburizing and sintering operations in high temperature furnaces; to cool extrusion dies; and to shrink fit metal parts; utilized as a purge gas with stainless steel tube welding. Also used to support plasma cutting.
• Electronics to prevent oxidation in the manufacture of semiconductors and printed circuits; and to enhance solvent recovery systems by eliminating the use of chlorofluorocarbons for cleanup.
• Glass Manufacturing to cool furnace electrodes and prevent oxidation during manufacturing; and to lower air temperatures for optimum cooling rates.
• Research and Health Services to freeze and preserve blood, tissue, semen and other biological specimens; to freeze and destroy diseased tissue in cryosurgery and dermatology; and to pre-cool or insulate Magnetic Resonance Imaging (MRI), conserving the more costly helium.
• Construction to suppress the pour temperature of concrete mixtures, inhibiting the formation of cracks; and to stabilize the ground as in the restoration of the Leaning Tower of Pisa.
• Recycling.  Nitrogen’s low boiling point and non-toxic properties make it an economical choice for recycling tires through cryopulverization. In this process, liquid nitrogen serves as a freezing agent and embrittles shredded tire scrap so that it can be easily ground into crumb rubber. The resulting product finds use in roofing materials, sealants, oil well linings, recreational surfaces and asphalt paving.

  A similar process is used to grind and sort polyvinyl chloride from post-consumer scrap in mixed waste loads, as well as to grind and process dried fruits, delicate herbs and spices.

Supply Options

• Bulk liquid delivery in tank trucks
• Bulk gas delivery in high pressure tube trailer trucks
• Portable Liquid Cylinders
• Portable insulated containers called dewars
• High pressure cylinders

Oxygen

Description Oxygen, or O₂, which comprises 21 percent of the earth’s atmosphere, supports life and makes combustion possible. The most abundant of all elements on earth, oxygen comprises 85 percent of its oceans and, as a component of most rocks and minerals, 46 percent of its solid crust. In addition, it constitutes 60 percent of the human body.

Colorless, odorless and tasteless, oxygen has poor solubility in water. A specific gravity of 1.105 makes it slightly heavier than air. When cooled to its boiling point of -297°F (-183°C), oxygen becomes a transparent, pale blue liquid that is slightly heavier than water.

Oxygen reacts with all elements, except inert gases, to form compounds called oxides. The rate of reaction – known as oxidation – varies. For example, magnesium oxidizes very rapidly, igniting spontaneously in air. However, noble metals, such as gold and platinum, oxidize only at very high temperatures.

Although oxygen itself is nonflammable, it enhances combustion and enables all materials that are flammable in air to burn much more vigorously. These combustion-supporting properties account for its use in many industrial applications.

Applications

Argon is used in diverse applications covering a number of industries, including:

• Steel Manufacturing to enrich air and increase combustion temperatures in blast and open hearth furnaces; to raise steel temperatures and enhance recycling of scrap metal in electric arc furnaces; and to replace coke as the combustible in steel making.
• Chemical Processing to alter the structure of feedstock through oxidation, producing nitric acid, ethylene oxide, propylene oxide, vinyl chloride monomer and other building block chemicals; and to increase capacity and destruction efficiency of waste incinerators.
• Pulp and Paper to help manufacturers meet stringent environmental regulations in a variety of mill processes including delignification, bleaching, oxidative extraction, chemical recovery, white/black liquor oxidation and lime kiln enrichment.
• Metal Production to replace or enrich air, increasing combustion temperatures in ferrous and non-ferrous metals production; to create a hot flame in high-temperature welding torches used in cutting and welding.
• Metal Fabrication to support oxyfuel cutting operations. Sometimes added in small quantities for shielding gases.
• Glass Manufacturing to enhance combustion in glass furnaces and fore hearths, reducing nitrogen oxide (NOx) emissions to levels below new stringent requirements of the U.S. Clean Air Act.
• Petroleum Recovery and Refining to reduce viscosity and improve flow in oil and gas wells; to increase capacity of fluid catalytic cracking plants as well as to facilitate use of heavier feedstock; and to reduce sulfur emissions in refineries.
• Health Services to resuscitate or, in combination with other gases, to anesthetize, but also essential to life-support systems used in emergencies or long-term treatment of patients with respiratory disorders.
• Utilities.  USW’s experience in gases and combustion help utilities improve boiler performance, efficiency and the environment.
• Waste water treatment because it supports life, oxygen is used in industrial and municipal wastewater treatment facilities. Using 90 to 99 percent oxygen instead of air boosts the biological activity required to eliminate wastes in water. And, with a 90+ percent utilization rate, oxygen provides an efficient and economical way for industrial complexes to meet U.S. Clean Air Act and Clean Water Act requirements.]

Supply Options

• Bulk liquid delivery in trailer trucks
• Bulk gas delivery in tube trailer trucks
• Portable cryogenic cylinders
• High pressure cylinders