Helium
is the 2nd most abundant element in the universe and wasn’t discovered until 1868, when it was discovered during a solar eclipse. Helium is a product of normal radioactive decay deep in the earth. Few places have the right geological conditions to keep it from escaping from the ground into the air. The LaBarge Madison reservoir in Wyoming is such a place. The gas stream there contains about sixth-tenths of 1 percent helium. Due to the fact that the site produces about 700 million cf of gas a day, there is about 4 million cf of helium produced daily. Processing
specialized equipment and technology are required to process and refine helium. First nitrogen and helium are extracted from natural gas leaving a stream that contains about 50 percent nitrogen. The gases are then transported through vacuum-jacketed piping at minus 270 degrees Fahrenheit to the helium plant, where the helium is further refined and the remaining nitrogen and contaminants are removed. The end product is more or less pure helium. Some is sold in a gas state but most of it is undergoes another series of complex processes to turn it into a liquid. Because of it’s chemical structure helium doesn’t freeze, but it will turn into a liquid when reduced to a temperature of minus 452 degrees Fahrenheit. In order to bring the temperature so low the helium goes through a series of cryogenic exchangers where pressure drops occur across four specifically designed gas turbine expanders, which can spin up to 3,500 revolutions per second. By the time the helium leaves the vessel it will be in liquid form and the coldest substance on earth. The liquid helium then flows through vacuum jacketed pipelines that feed specialized truck trailers or fill vacuum jacketed storage tanks, which can hold over 60,000 gallons of liquid helium. As recent ago as 1986 about 20 percent of the helium was lost during processing, now that number has been reduced to about a 2 percent loss.General Facts
- Chemical symbol: He
Second lightest elemental gas, after hydrogen
Smallest of all molecules
Lowest boiling point of any element (-452.1°F, -268.9°C, 4.2 K, 7.6 R)
Seven times lighter than air
Conducts sound three times faster than air
Has five times air’s thermal conductivity
Does not become radioactive under irradiation
Physical Properties
- Colorless
Odorless
Tasteless
Non-toxic
Inert
Non-flammable
Slightly soluble in water
High thermal conductivity
In the Environment
- Helium is produced continually by the radioactive decay of uranium and other elements, gradually working its way into the atmosphere.
- Helium atoms are light enough to escape the Earth’s gravitational field and into space.
- Commercial extraction from air is impractical because helium’s concentration is only about five parts per billion.
Where It’s Found
- Commercially, helium is obtained from the small fraction of natural gas deposits that contain helium volumes of 0.3 percent or higher.
- Most of the world’s helium comes from the Texas panhandle, Oklahoma, Kansas and the Rocky Mountains’ eastern flank, other sources include the mid-
east and Russia.
- These natural gas deposits contain more than 3,000 ppm of helium.
Unusual Characteristics
- At atmospheric pressure, helium becomes liquid at the lowest of all boiling points (-452°F, -269°C, 7.6 R).
- Helium remains liquid to absolute zero.
- The coldest known substance, helium is important for cryogenic research.
- At 3.9 R, liquid helium exhibits super fluidity or virtually zero viscosity (Helium II), defies gravity to flow up container walls and becomes nearly a perfect heat
conductor.
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 cargo ranging from weather forecasting instruments, television equipment and radar stations to communications relays.
- to limit narcosis and oxygen toxicity in the diver
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 semi conducting 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