Gas Liquefaction Nick Kretschmar

Background Most gases were able to be liquefied in the 1800's First done with a beaker in ice water to compress and cool the gas All gases have a critical temperature which means the gas cannot liquify at any pressure unless it is less than this temperature

Uses Transportation and storage because the density increases greatly Oxygen in space for burning fuels Nitrogen in Cryogenics Helium for near 0 K temperatures and low viscosity

Methods Cascade process- Using liquefied gas to liquify another Compression- apply pressure to the gas at a temperature below the critical temperature External work by the gas- the gas is cooled and run through a turbine which causes it to loose energy and cool Joule-Thomson effect- compressing and then rapidly expanding the gas

Joule-Thomson effect First a gas is compressed at room temperature The gas is then released through a small valve This causes the gas to expand quickly and therefore the temperature to drop Any gas not turned into liquid is run through the cycle again The liquid collects and is removed

References http://www.scienceclarified.com/Ga-He/Gases-Liquefaction-of.html http://www.bookrags.com/research/gas-liquefaction-of-wsd/ http://www.chem.arizona.edu/~salzmanr/480a/480ants/jadjte/jadjte.html http://history.nasa.gov/SP-4404/app-a1.htm

Any questions? Nick Kretschmar Gas Liquefaction