Patent ID: 6187278
Filing Date: 2001-02-13
Classification: B01D

Abstract:
A process for removing sulfur dioxide from flue gases, the method comprising the steps of:delivering flue gases containing sulfur dioxide to a contactor region of an absorber;introducing a scrubbing solution containing ammonium sulfate into the absorber, the scrubbing solution contacting the flue gases and absorbing sulfur dioxide from the flue gases;accumulating the scrubbing solution containing the sulfur dioxide in a vessel having a bottom wall and a side wall that defines a cross-section of the vessel;introducing a mixture of an oxygen-containing gas and a dilute ammonia-containing fluid into the scrubbing solution within the vessel through a single injections means to react with the sulfur dioxide to produce ammonium sulfate, the mixture of the oxygen-containing gas and the dilute ammonia-containing fluid being introduced into the vessel in a direction toward the bottom wall of the vessel and dispersed evenly across the cross-section of the vessel at the bottom wall of the vessel; andrecirculating the scrubbing solution to the contactor region,wherein the mixture of the dilute ammonia-containing fluid and oxygen-containing gas is intermixed with the scrubbing solution within the vessel and prior to the scrubbing solution within the vessel being recirculated to the contactor region so as to eliminate portions of scrubbing solution within the vessel having a higher pH and a higher ammonium sulfite level than the remainder of the scrubbing solution within the vessel.