Marines also are proud to say that 'every Marine is a rifleman.' In other words, regardless if you are in the infantry, the air wing or a computer technician, you will given the proper training so that, if need be, you can perform as an infantryman if called upon.
Natural gas is rising to the surface due to its natural tendency to fill areas with the lowest pressure. Since gas produced from a well contains many admixtures, it is first taken for treatment. Comprehensive gas treatment units are built not far from certain fields; in some cases, gas is instantly taken to a gas processing plant.
The most common commercial method for producing oxygen is the separation of air using either a cryogenic distillation process or a vacuum swing adsorption process. Nitrogen and argon are also produced by separating them from air. Oxygen can also be produced as the result of a chemical reaction in which oxygen is freed from a chemical compound and becomes a gas. This method is used to generate limited quantities of oxygen for life support on submarines, aircraft, and spacecraft.