Patent ID: 7198698

Claim:
A method of removing ammonia from an effluent gas stream comprising: a. irradiating with ultraviolet light a gas stream produced by an industrial process where the gas stream emitted from the industrial process contains ammonia at concentrations less than 40 ppm; b. substantially reducing the concentration of the ammonia present in the gas stream emitted by the industrial process by irradiating the gas stream with UV light in the spectral range of 230 to 370 nanometers to cause the photolysis of nitrogen dioxide (NO 2 ), ozone and hydrogen peroxide present and/or formed in the gas stream emitted by the industrial process; c. initiating a set of hydroxyl and hydroperoxy free radical reactions that result in the removal of a hydrogen atom from the ammonia to form an NH 2 radical wherein the initiation of the free radical reaction is a result of irradiating the gas stream with the UV light in the spectral range of 230 to 370 nanometers; and d. maintaining a NO x concentration in the gas stream at a concentration level sufficient to maintain in the gas stream the active set of hydroxyl and hydroperoxy free radical reactions.