Effectiveness Of Continuous Removal Of Heat Stable Salts From Contaminated Amine Scrubbing Solutions

Amine scrubbing solutions used for gas treatment at refineries, chemical, sulfur and gas processing plants remove hydrogen sulfide and carbon dioxide from gas streams. One of the problems with the amine solutions is the gradual accumulation of byproduct contaminants called heat stable salts (HSS). Increased HSS concentration in the amine loop leads to corrosion-related maintenance problems, frequent filter replacements, amine losses, excessive foaming, capacity reduction, etc.

Ion exchange resins have been employed for removal of the HSS, but because of the different affinities that the various anionic HSS contaminants have towards the resin, successful removal is restricted. Moreover, continuous online removal of the HSS, rather than periodic treatment helps ensure a more stable and uniform conditioning operation with optimized efficiency of the amine unit operation.

A proprietary system, employing advanced ion exchange technology with unique features of fine mesh resins, short packed bed and fast cycles was introduced to this application about 10 years ago and has proved most successful in achieving the needs of efficient online HSS removal. Since then, several such systems have been installed around the world including India. This paper details the technology and various applications, including carbon dioxide sequestration. Various examples are presented, with two specific case studies: a system installation in the United States of America, and an installation in China.