Patent ID: 8353980

Claim:
A process for removing acidic gases from a flue gas, the process comprising: causing the flue gas to flow upward through a contact zone within a passage; contacting the flue gas within the contact zone with an ammonium sulfate-containing scrubbing solution to absorb the acidic gases from the flue gas and yield a scrubbed flue gas; accumulating the scrubbing solution and the absorbed acidic gases; injecting oxygen and ammonia into the accumulated scrubbing solution to react the absorbed acidic gases and produce ammonium sulfate; flowing an acid solution across the passage on at least a first perforated tray located within the passage above the contact zone of the passage and above at least a first mist eliminator within the passage; flowing the scrubbed flue gas upward through openings in the first perforated tray and through the acid solution on the first perforated tray to remove unreacted ammonia from the scrubbed flue gas, the openings in the first perforated tray being sized relative to the flow of the flue gas so that essentially all of the acid solution is retained on the first perforated tray and does not flow downward through the openings thereof and into the contact zone; and removing the acid solution from the passage after the acid solution has been contacted by the scrubbed flue gas.