Amine plants where stringent gas specifications must be met and cooling water is not available. Carbon dioxide (CO2) removal down to 50 ppmv (liquefied natural gas {LNG}specification) and hydrogen sulfide (H2S) removal down to 4 ppmv at treating pressures as low as 50 psig.
Description: Feed gas is contacted with a diglycolamine (DGA) solution in the contactor (1) where acidic impurities react with the amine. The rich solution is flashed to recover hydrocarbons (2), heated by exchange with the hot lean solution (3), and then flows to the solvent regenerator (4). Acid gases and water vapor pass overhead to the condenser (5).
Condensed water is returned to the regenerator while the acid gases go to flare, sulfur recovery or further processing. Regenerator heat can be furnished by suitable heat media or direct firing. Lean solution is pumped from the regenerator through the exchangers and coolers to the contactor. Amine degradation by COS and carbon disulfide (CS2) is completely reversible by reclaiming (5) at elevated temperatures. The reclaimer provides part of the regenerator heat.
The Fluor improved ECONAMINE process is designed for plants using all air cooling in a hot environment. The process adds a side cooler (6) to the absorber to remove a significant portion of the reaction heat. Amine circulation is reduced, which results in lower capital costs in the plant’s regeneration section.
The Fluor ECONAMINE process uses an aqueous DGA solution. Solution concentrations up to 65 wt% DGA result in appreciably lower circulation rates and steam consumption, which in turn, results in substantial savings in both capital and operating costs when compared to other amines. Aqueous DGA has a very low freezing point, below –40°F, making it suitable for Arctic climates where winterization is an issue.
Licensor: Fluor Enterprises, Inc.
