Patent ID: 8758493

Claim:
A system for reducing an amount of ammonia in a flue gas stream, the system comprising: a wash vessel including: a first input opening to receive an ammonia-containing flue gas stream; a first absorption stage and a second absorption stage disposed above the first input opening, each of the first absorption stage and the second absorption stage having a mass transfer device, wherein the first absorption stage is disposed above the second absorption stage, each of the mass transfer devices of the first absorption stage and the second absorption stage includes a type of packing material selected from structural packing material, hydrophilic packing material or random packing material; and the mass transfer device of the first absorption stage is of a different type of packing material than the mass transfer device of the second absorption stage; a second input opening disposed above the first absorption stage and the second absorption stage, wherein the second input opening receives a liquid which flows downward in counter current direction to the ammonia containing flue gas sequentially through the first absorption stage and the second absorption stage for absorbing ammonia from the ammonia-containing flue gas stream, thereby forming an ammonia-rich liquid and a reduced ammonia containing flue gas stream exiting the wash vessel; and a third input opening disposed below the first absorption stage and above the second absorption stage, wherein the third input opening receives a liquid which flows downward in counter current direction to the ammonia containing flue gas sequentially through the second absorption stage for absorbing ammonia from the ammonia-containing flue gas stream.