urface where droplets stick and grow. As the droplets grow their weight increases and ultimately they will fall to the bottom of the vessel.
             To determine the proper scheme for gas processing we must first look at the raw gas composition. Raw gas streams can contain a combination of Nitrogen, Hydrogen Sulfide (H2S), Mercaptan Sulfur, Carbon dioxide (CO2), heavier hydrocarbons (heavier than methane ex. ethane, propane, etc.), water in varying concentrations. If the stream contains sulfur compounds it is referred to as a sour gas and if the stream is void of sulfur it is referred to a sweet gas. Once the bulk liquids are removed the various components must be dealt with by first addressing the sulfur and carbon dioxide components followed by the saturated water and finally the heavier hydrocarbons. Most gas streams do not contain enough nitrogen to require removal so often the nitrogen passes through as an inert. However, there are processes that do exist to address the removal of nitrogen when it becomes necessary. Sour gas processing involves a number of different techniques but the bulk of the industry utilizes aqueous alkanolamine technology or amine sweetening processes to remove sulfur compounds and carbon dioxide. This process involves contacting an amine solvent with the gas stream in a trayed vessel known as a contractor that chemically reacts with the H2S and CO2 but not with hydrocarbons. The amine is a weak base and the H2S & CO2 are acids in the presences of water and the resultant is an amine salt commonly referred to as rich amine. The rich amine exits the contractor as a
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