Selecting mixed amines for sweetening units

The removal of sour or acid gas components such as hydrogen sulfide ( H۲s), carbon dioxide (CO۲),carbonyl sulfide (COS) and mercaptans (RSH) from gas and liquid hydrocarbons stream is a process requirement in many parts of the hydrocarbon processing industry. This is especially true with the increasingly stringent environmental considerations couples with the need to process natural gas and crude oil with increasinglyhigher sulfur levels. Typical industrial gas treating applications include the production of natural gas, refinery fuel gas, high purity H۲ and CO۲, and purification of ammonia, synthesis gas, landfill gas, coke oven gas or sulfur recovery unit tail gas. Numerous alternatives of gas treating processes are available. Gas composition, processing pressure and temperature, quantity of sour gas to be processed, product gas specification and subsequent processing equipments of both the acid gas and the treated gas are some of the factors which must be considered when selecting a gas treating process. Once the process equipments of the application has been defined, a specific process must be selected based on additional factors such as plant investment and operating cost, climatic conditions and ease of operations. The chemical solvent process, using the various alkanolamines, is the most widely employed gas treating process. In this article we are going to study the affection of operationfactors such as temperature, pressure and type of amine solution and affection of mixing different kind of amines on rate of H۲S in sweet gas. In addition to them we consider operating costs like pump and reboiler duty.

Keywords:

gas treating , amine solution , mixture of amine , simulation , hysys , Tabriz refinery