There are a number of technologies available for the removal of acid gases (primarily H2S and CO2) from gas streams.

Some of these technologies can also be used for the removal or recovery of H2S and CO2 from gas and flue gas streams.

These technologies can be broadly categorised as follows:

• Reversible Chemical Reaction (Benfield / MEA / DEA/ MDEA)
• Physical Solvent Process (Selexol® / Sufinol® / Fluoramine® )
• Dry Bed Adsorption Processes (Iron Sponge / Activated Carbon / Molecular Sieve)

There are many variables involved in specifying and selecting gas treatment technologies. Some of the factors to be considered include:

• Type & quantity of impurity in the sour gas
• Outlet specification for the residue gas
• Outlet specification for the acid gas
• Inlet conditions (temperature/pressure) of sour gas

• Volume of gas to be processed
• Hydrocarbon composition of the gas
• Required selectivity of acid gas removal
• Waste disposal