Abstract: The improved method for treating waste gases by exposure to electron beams which comprises adding ammonia to a waste gas containing sulfur oxide (SO.sub.x) and/or nitrogen oxides (NO.sub.x) and thereafter exposing the gas to an electron beam so as to remove the sulfur oxides and/or nitrogen oxides therefrom is characterized by first mixing ammonia gas uniformly with air, then forming a homogeneous gas-liquid mixture from said gaseous mixture and water, and spraying said homogeneous mixture into a reactor. Efficient desulfurization can be realized even if the temperature of the waste gas being treated is fairly high at the exit of the reactor and the concentration of ammonium sulfamate in the by-product ammonium sulfate can be reduced.

Abstract: A process for desulfurization and denitration of waste gas by multi-stage electron beam irradiation and an apparatus used for the process are constituted so that the waste gas is passed through the electron beam irradiation zones in multiple irradiation chambers that are arranged in such a way that the center-to-center distance (m) between two neighboring electron beam generators is not shorter than distance X calculated by the formula, X=2.alpha.+tV wherein 2.alpha. means distance over which an absorbed dose extends into a waster gas, t means a residence time (sec.) of waste gas in a non-irradiation zone, and V stands for the flow velocity of waste gas, whereby t can be reduced to 0.01-0.5 seconds, so that irradiated energy can be utilized efficiently and a maximum effect can be obtained with a minimum expenditure of irradiation energy. Therefore, the waste gas can be treated rapidly and economically.

Abstract: A method of removing harmful gas from a refuse combustion exhaust gas. The refuse combustion exhaust gas, containing a harmful gas such as hydrogen chloride, is supplied to a reactor. Other steps include atomizing an alkaline material within the reactor, and applying radiation, such as an electron beam, to the refuse combustion exhaust gas, simultaneously with the atomizing of the alkaline material, thereby causing a reaction between the gas and the alkaline material, and recovering a salt produced by the reaction.