Acetylene

Description

Acetylene (C₂H₂) is a colorless, highly flammable gas.

Applications Used in optical spectrometry as an instrumentation gas; used in atomic absorption for elemental analysis as an instrumentation gas. Used as a fuel gas in atomic absorption spectrometry for elemental analysis.

Materials Compatibility Metals: Stainless Steel; Carbon Steel; Aluminum; Monel; Brass (Low Copper)
Plastics: Kel-F; PTFE, FEP, and PFA Fluoropolymers resins; Tefzel; Kynar
Elastomers: Kalrez; Viton; Buna-N; Neoprene; Polyurethane

 

Carbon Dioxide

Description Carbon Dioxide, CO₂, is a tasteless, colorless, odorless, nonflammable, liquefied gas. Carbon dioxide is an integral part of the basic life cycle in nature. It is exhaled by humans and animals, then used by plants to help them grow. Plants, in turn, release oxygen, which people depend on for survival.

Unlike atmospheric gases, air separation is not the primary source of carbon dioxide. Though sometimes it is derived from directly combusting a fuel, the most economical way to produce carbon dioxide is to recover it as a byproduct from other companies’ manufacturing processes or from natural wells. Then it is purified and liquefied and sold to our customers worldwide.

Applications Carbon Dioxide is used in diverse applications covering many industries, including:

• Food and Beverage.  Carbon dioxide is used in beverage carbonation. A natural anti-microbial, carbon dioxide is also used to increase the shelf life of juice and dairy products, protecting taste and texture, and reducing the need for preservatives, natural and artificial. Other applications include: food freezing and chilling, packaging, mixer and blender cooling, ingredient cooling and conveying, and in-transit refrigeration. In its solid form, it is known as dry ice. Many people know carbon dioxide is used in food freezing, carbonated beverages and dry ice. But most don’t realize it also helps to clear the air, clean the water and save the trees.
• Water Treatment.  Industrial and municipal wastewater must be neutralized before being discharged to the environment. Carbon dioxide replaces harsher acids for the alkaline neutralization process. It’s safer and cheaper than sulfuric-acid systems, improves controllability, and there’s less downtime and no labor to handle chemicals. It also is less corrosive, and easier to handle and store.
• Metal Fabrication.  Commonly utilized as a shielding gas during welding. This prevents atmospheric contamination of molten weld metal during gas shielded electric arc welding process.
• Plant Growth.  Carbon dioxide systems greatly improve growth and quality of plants in the greenhouse. Increasing concentrations of the gas results in larger, healthier and faster-growing plants and lower operating costs, especially during the winter, when it can reduce heating costs by 50%. Carbon dioxide replaces gas generators, saving fuel costs and eliminating harmful emissions.
• Pulp and Paper.  Carbon dioxide is being used for several different applications within paper mills, all developed to reduce costs and recover valuable chemicals used within the mill process. A process using carbon dioxide, instead of sulfuric acid, to treat pitch build-up in screen rooms is proving very successful.
• Saving the Forest.  Carbon dioxide is used to make precipitated calcium carbonate (PCC), which is used to reduce the use of virgin wood fiber in paper making. Applications include: supply of carbon dioxide for on-site PCC production and in-situ formation of PCC during the paper-making process.
• Energy Source.  Storage of carbon dioxide at its triple point (the temperature-pressure combination at which carbon dioxide can exist simultaneously as a solid, liquid or gas) is being tested as a means of providing closed-loop refrigeration in order to shift electrical-energy demand to off-peak consumption hours. Under test in Japan, the process offers the potential to customers to shift electrical load while maintaining temperatures as low as minus 60°F (-51°C).
• Cleaning and Solvent Extraction.  In its supercritical state (87.9°F (31.1°C) and 1070.6 psia (7.38MPa)), carbon dioxide becomes a versatile solvent. It can replace chlorinated fluorocarbons to clean equipment components. It also can replace many volatile organic chemicals for operations such as decaffeinating coffee or extracting fat from food products.
• Fire Fighting.  Carbon dioxide smothers fires without damaging or contaminating materials and is used for fighting fires when water is ineffective, undesirable or unavailable.

Supply Options

• Bulk liquid delivery in trailer trucks
• Portable cryogenic cylinders
• Cylinders

Helium

Applications

Aerospace – Pressurizing, Inerting and Thermal Control.  Helium plays a unique and critical role in the pressurizing and purging of primary rocket propulsion systems. The propellant for these propulsion systems is a combination of liquid hydrogen and liquid oxygen.

Helium is vital for purging and pressurizing the liquid hydrogen fuel systems of rockets and spacecraft because of its:

• Low solubility
• Low boiling point (-452°F, -269°C)
• Inertness

Helium is also the only inert substance that remains a gas in such low temperature environments.

Aerostats and Balloons.  For decades, USW helium has been giving a lift to everything from simple party balloons to sophisticated lighter-than-air aircraft and aerostats carrying cargos ranging from weather forecasting instruments, television equipment and radar stations to communications relays.

Electronics. The world of electronics we often take for granted would not be possible without helium. That’s because helium:

• Creates the controlled environments necessary for manufacturing semiconducting devices.
• Provides enhanced thermal conductivity.

Leak Detection.  In addition to creating controlled environments, helium’s small molecules make it ideal for use with pressure and vacuum systems to detect and locate minute leaks that could impact the production and quality of semiconductors, and ensure that these systems are free of leaks.

Purity and Delivery USW offers the semiconductor industry several helium purity options, including STANDARD and ELECTRONICS grades.

Supply Options

• Tube trailers, which can be connected to a customer’s systems
• Receivers, which can be installed on-site and filled as required
• Bulk liquid containers
• Cylinders