NOVELTY - An ammonia contact scrubber system (10) comprises a contact scrubber (12) and an acid circulating loop (26). The contact scrubber includes a scrubber fuel inlet (14) configured to receive a hydrogen-rich fuel for the fuel cell (16), and a scrubber fuel exhaust (20) configured to direct flow of the hydrogen-rich fuel from the scrubber into the fuel cell. The acid circulating loop includes an acid holding tank (28) configured to hold a liquid acid solution (30), an acid feed line (32), an acid return (38), and an acid circulation unit (42).    USE - Ammonia contact scrubber system is used for removing ammonia from hydrogen-rich fuel stream of fuel cells (claimed) used in transportation vehicles, portable power plants, and stationary power plants.    ADVANTAGE - The ammonia contact scrubber system is compact and economical, and can be operated efficiently for long periods of time without high-frequency maintenance. The scrubber eliminates the use of filters and ion beds.    DETAILED DESCRIPTION - An ammonia contact scrubber system (10) comprises a contact scrubber (12) and an acid circulating loop (26). The contact scrubber includes a scrubber fuel inlet (14) configured to receive a hydrogen-rich fuel for the fuel cell (16), and a scrubber fuel exhaust (20) configured to direct flow of the hydrogen-rich fuel from the scrubber into the fuel cell. The contact scrubber houses a support material (24) and is configured to direct flow of the fuel from the scrubber fuel inlet through the support material to the scrubber fuel exhaust. The acid circulating loop includes an acid holding tank (28) configured to hold a liquid acid solution (30), an acid feed line (32), an acid return (38), and an acid circulation unit (42). The acid feed line is secured in fluid communication between an acid holding tank outlet (34) of the holding tank and a scrubber acid inlet (36) of the contact scrubber. The acid return is secured in fluid communication between a scrubber acid outlet (40) of the contact scrubber and the acid holding tank. The acid circulation unit is secured in fluid communication with the acid feed line and configured to pump the acid solution through the acid circulating loop.    DESCRIPTION OF DRAWING(S) - The drawing shows a simplified schematic view of the ammonia contact scrubber.    Ammonia contact scrubber (10)    Contact scrubber (12)    Scrubber fuel inlet (14)    Fuel cell (16)    Scrubber fuel exhaust (20)    Support material (24)    Acid circulating loop (26)    Acid holding tank (28)    Liquid acid solution (30)    Acid feed line (32)    Acid holding tank outlet (34)    Scrubber acid inlet (36)    Acid return (38)    Scrubber acid outlet (40)    Acid circulation unit (42)