What Does Acid Gas Removal (AGR) Mean?
Acid gas removal (AGR, also known as amine scrubbing, and amine gas treating) refers to a group of industrial chemical processes which use solutions of amine chemicals to separate hydrogen sulfide (H2S) and carbon dioxide (CO2) from gaseous mixtures. AGR is also referred to as gas sweetening, because the removal of hydrogen sulfide improves the odor of the processed product. This process takes place in dedicated amine treatment facilities, and is used in petrochemical plants and refineries to bring the product being treated to a necessary level of purity. Acid gas removal is a closed process with little potential for chemical exposure during normal operations. However, corrosion or oxidation of improperly maintained or operated amine plants may increase the risk of chemical exposure or fire within a facility.
Safeopedia Explains Acid Gas Removal (AGR)
There are more than 30 acid-gas removal processes available commercially. AGR is typically done so that the treated product will meet environmental emissions regulations or to allow the treated product to be processed further using methods that are incompatible with acidic gases. The most common amines used in gas treating are diethanolamine (DEA), monoethanolamine (MEA), and methyldiethanolamine (MDEA).
Specific regulations relevant to AGR treatment facilities include OSHA standard 1910.101 for compressed gasses. OSHA advises that the occupational safety concerns associated with exposure to amine compounds, hydrogen sulfide and carbon dioxide are minimal as amine treatment is a closed process. However, the risk of exposure may increase during sampling, inspection, maintenance, and turnaround activities. Additionally, accidental spills or leaks of some chemicals carry a risk of fire hazard. Use of personal protective equipment (PPE) may be necessary in some situations.
Proper operating processes are also required to minimize corrosion and oxidation of material within amine treatment facilities. Excess corrosion may result in structural damage to the facility. This could cause unsafe conditions, including catastrophic structural failure. In 1984 a corroded AGR facility at a refinery released large quantities of flammable gases and vapors, resulting in explosion and fire. Seventeen persons died and seventeen others were injured.