Evaluation of amines for the removal of acid gases from the liquid hydrocarbons

Liquefied Petroleum Gas (LPG) is a product made from crude oil and has several domestic and industrial applications. Continuous increases in energy demand around the world and strict environmental regulations require clean fuel for various applications. This requires the cleaning of liquid hydrocarbons from acid gases which are toxic to human health and disastrous to industrial equipment. Currently, most of the liquid hydrocarbon treatment is done using caustic solutions to remove acid gases. However, depending on the concentration of impurities in the feed and the amount of feed to be processed, a large amount of caustic solution is required which poses another disposal issue. This study proposes to replace the conventional caustic cleaning process with the amine process for liquid hydrocarbon treatment. The process consists of a liquid-liquid contactor where impurities are removed using the amine and then rich amine is regenerated in the stripper column. This study's goal is to assess various amine types for removing acid gases from liquid hydrocarbon feeds. The study is conducted using commercial simulation software ASPEN HYSYS® for the design and analysis of process performance. The studied variables include the concentration of the amine, the amine circulation rate, the effect of LPG feed temperature, and the lean amine temperature. The outcomes demonstrate that the removal of acid contaminants from the hydrocarbons can be a competitive process to achieve the required product purities.