Refinery gas treating processes

Refinery gas sweetening is the process used to remove the so called ‘Acid Gasses’ which are hydrogen sulfide and carbon dioxide from the refinery gas streams. These acid gas removal processes used in the refinery are required either to purify a gas stream for further use in a process or for environmental reasons. Clean Air legislation now being practiced through most industrial countries require the removal of these acid gases to very low concentrations in all gaseous effluent to the atmosphere. Hydrogen Sulfide combines with the atmosphere to form very dilute sulfuric acid and carbon dioxide to form carbonic acid both of which are considered injurious to personal health. These compounds also cause excessive corrosion to metals and metallic objects.

The following sections of this chapter describe the processes, their chemistry and a method of calculating the design of the more common processes.