Sparging
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Sparging in chemical sciences refers to the bubbling of a chemically inert gas through a liquid.
In chemical engineering it is commonly used as a method of removing a liquid from a solution by bubbling dry air through the solution. Liquids with higher vapor pressures will tend to evaporate faster than liquids with lower vapor pressures. This is an alternative to distillation, in which liquids with lower boiling points will evaporate faster. Sparging can be safer than distillation because it doesn't require heating the solution to the boiling point of any of its components.
Sparging with air is done in environmental chemistry to remove petroleum contaminants from groundwater and soil. [1] (http://www.epa.gov/swerust1/cat/airsparg.htm)
Sparging is also used in chemistry to remove dissolved gases from a solution by bubbling a different inert gas through the liquid. Nitrogen gas is commonly used to aid in removal of dissolved oxygen gas, preferably when the liquid to be degassed is refluxing under positive nitrogen pressure.
Sparging has another definition as the sprinkling of water. This definition is currently used (as a synonym to lautering) to describe the addition of water to extract liquid from the wort in the beer brewing process. The term is thought to come from the practice of ancient priests who used green asparagus tips ("Der Spargel" in German) to sprinkle holy water.fr:Barbotage