Patent ID: 6852292

Claim:
In an engine which includes means for combusting hydrocarbons in air to produce work wherein said means also produces a stream of exhaust gasses that contain nitrogen oxides, with the engine having an exhaust conduit through which the exhaust gasses are passed before being emitted into the atmosphere, the improvement comprising: a source of ammonia: an injector apparatus coupled to said source to receive ammonia therefrom and inject the ammonia into said exhaust conduit; said source of ammonia comprises a container containing a mixture of ammonia and water; said injector apparatus includes a tube that lies in a heat-exchange relationship with said exhaust conduit to use the heat of the exhaust gasses to heat the mixture of ammonia and water, and a separation station that receives said heated mixture and separates liquid water from gaseous ammonia, and directs them along different paths, and that injects the gaseous ammonia into said exhaust conduit.