Method for reducing regeneration energy

摘要

A process and an apparatus are described, which remove acid gas from a gas stream in a manner that generates a product gas stream at a higher temperature while consuming less energy than the existing technology. The process requires maintaining a positive product gas temperature differential. The apparatus enables the positive gas temperature differential to be maintained by manipulating the absorber column operating conditions and/or the solvent chemistry to increase the amount of absorption and reaction in the absorber.

主权项

1. A method of removing acid gases from a gas stream, comprising the steps of:
providing an absorber column; providing the gas stream to the absorber column; providing a lean solvent solution stream comprising an aqueous amine-based solvent solution to the absorber column; contacting the gas stream and the lean solvent solution stream in the absorber column to produce a product gas depleted of acid gases and a rich solvent solution; measuring a product gas temperature of the product gas in the absorber column at a first location proximal to where the lean solvent solution stream first contacts the gas stream; measuring a lean solvent temperature of the lean solvent solution stream at a second location proximal to where the lean solvent solution stream first contacts the gas stream; providing a regenerator; providing the rich solvent solution to the regenerator to produce a regenerated solvent solution stream; providing a heating unit wherein the regenerated solvent solution stream from the regenerator is heated by heat exchange relationship with heating fluid from the heating unit; adjusting at least one of the lean solvent temperature, a recirculation rate of the lean solvent solution stream, and a solvent-to-water ratio of the lean solvent solution stream to result in a product gas temperature elevation greater than 5° C., thereby reducing regeneration energy, wherein the product gas temperature elevation is the difference between the product gas temperature and the lean solvent temperature; and discharging a product gas stream of the product gas from the absorber column.