Corrosion in natural gas: amine-sweetening units.

Corrosion in natural gas: amine-sweetening units. The corrosion in such systems is mainly caused by acidic components such as (CO₂ and H₂S) dissolved in the amine, amine degradation products, heat-stable amine salts, and other contaminants. This can be general or localized, and mainly attacks carbon steel parts.
Among the HSAS are the anions: acetate, format, oxalate, chloride, nitrate and nitrite, sulfide, sulphide, thiosulfate, thiocyanate, phosphate. These have a significant impact on corrosion when their concentration is greater than 2% m/m in the mixture.
Another factor to consider is the type of amine, since there is a difference in the order of aggressiveness between them, which influences the maximum value allowed for compounds that promote corrosion.
The most common methods to avoid this problem are a controlled operation and maintenance of the amine solution, and a proper selection of building materials and manufacturing processes.