Patent ID: 6928807
Filing Date: 2005-08-16
Classification: B01D,C01C,F01N,F17C,Y02A,Y02E,Y02P,Y02T

Abstract:
1. An apparatus for producing ammonia (NH 3 ) and introducing the produced ammonia (NH 3 ) into an exhaust gas stream as a reduction means for selectively catalytically reducing nitric oxide contained in the exhaust gas stream, which is an exhaust stream generated by the combustion process of a motor, a gas turbine, or a burner, the apparatus comprising: a storage container in which urea in dry form in the form of powder, granulate, or micro-prills is stored; a reactor for the production of ammonia (NH a device for feed of the urea, preferably in controlled or measured amounts, from the supply container into the reaction chamber of the reactor; an electrical heating element in the thermal treatment zone of the reaction chamber of the reactor; a device for controlling the temperature of the heating element in a manner such that the urea introduced into the reaction chamber is spontaneously de-composeable, via flash hydrolysis, into ammonia (NH a device for introducing water in at least one form of completely liquid water and a water-containing gas-into the reaction chamber of the reactor, the device for introducing water includes a feed conduit and an electrically controllable blocking valve in the feed conduit and moveable between open and closed positions and, preferably, movable as well into flow through amount-controlling intermediate positions, the movement of the blocking valve into its respective positions being controllable by the device for controlling the temperature of the heating element; and a hydrolysis catalyzer in the hydrolysis treatment zone of the reaction chamber of the reactor for converting, in the presence of water, the isocyanic acid (HCNO), which is produced from the flash hydrolysis of the urea in addition to ammonia (NH