Читать книгу Encyclopedia of Renewable Energy - James Speight G., James G. Speight - Страница 81

The removal of acid gases by the alkanolamine process (amine process) is accomplished by a chemical reaction. Physical solvents (Selexol, Sulfinol, Propylene Carbonate) remove acid gases by straight absorption or a combination of absorption and chemical reaction.

The alkanolamine can be categorized on a chemical basis as being primary (MEA, DGA), secondary (DEA, DIPA), and tertiary (MDEA, TEA) depending on the number of substitutions onto a central nitrogen atom. Solvents currently in use include formulated MDEA (Ucarsol, Gas Spec) and hindered amines (FLEXSORB). This chemical structure influences each properties of the alkanolamine as a treating solvent and therefore, lend themselves to different applications.

Furthermore, the following is a list of conditions must be defined when selecting a treating solvent: (i) the operating pressure and temperature, (ii) the amount of acid gases and quantity removed, selectivity, and treated gas specifications, (iii) the disposal of the acid gases such as sulfur recovery and/or incineration, (iv) the contaminants in the inlet gas, such as oxygen, mercaptans and other sulfur species, free liquids, and gas composition, and (v) the environment, such as spill reporting and allowable ambient sulfur oxide emission.