Abstract: A process for reducing NOx concentrations in waste gas streams by contacting the waste gas stream with a reducing agent selected from ammonia and urea and then oxidizing the lower NOx's present in the waste gas streams to higher oxides with chlorine dioxide.

Abstract: A process for reducing NOx concentrations in waste gas streams by contacting the waste gas stream with a reducing agent selected from ammonia and urea and then oxidizing the lower NOx's present in the waste gas streams to higher oxides with sodium chlorite.

Abstract: A reducing agent and a readily-oxidizable gas are injected into a NOx-containing process stream to reduce the concentration of the NOx-containing process stream by a predetermined amount.

Abstract: A gas desulfurization process is provided in which a gaseous mixture comprising sulfur oxides is contacted in an absorption zone, at absorption conditions, with an aqueous composition comprising ammonium carbonate, or ammonium bicarbonate or mixtures thereof, in an amount such that the product of the partial pressures of the sulfur oxides and ammonia over said aqueous composition is below a specified limit, to produce a gaseous product having a decreased content of sulfur oxides and a decreased appearance of blue haze. A combination nitrogen oxides removal (deNO.sub.x) and desulfurization (deSO.sub.x) process is also provided.

Abstract: A combination gas denitrogenation and desulfurization process is provided in which a gaseous mixture comprising NO.sub.x, SO.sub.x and O.sub.2 is reacted with excess NH.sub.3 to reduce the NO.sub.x to N.sub.2 and the resulting gaseous effluent comprising the unreacted ammonia and SO.sub.x is passed to a gas desulfurization zone to form an ammonium salt of an acid of sulfur which can be recovered and used as such or converted to elemental sulfur.

Abstract: Disclosed is a process for non-catalytically removing NO.sub.x from combustion effluent streams at temperatures of about 1100.degree. K. to 1500.degree. K. and at superatmospheric pressure by injecting ammonia directly into a contacting zone where the combustion effluent has a residence time of above 2 milliseconds.

Abstract: Disclosed is a method for non-catalytically reducing the concentration of NO in combustion effluents by the injection of ammonia into an effluent stream where the stream is at a temperature from about 975.degree. K. to 1300.degree. K. More particularly, the amount of NH.sub.3 and its point of injection are determined by the solution of a set of simultaneous equations derived from the kinetic model disclosed herein. Particular benefits of the present invention occur when ammonia is injected into a cooling zone.

Abstract: Disclosed is a process for non-catalytically removing NO from combustion effluent streams at temperatures from about 1300.degree. K. to 1600.degree. K. by injecting ammonia into a combustion effluent stream at a point where the stream is cooling at a rate of at least about 250.degree. K./sec, wherein the amount of ammonia injected and its point of injection are determined by the solution of a set of simultaneous equations derived from the kinetic model of Table I hereof.

Abstract: Disclosed is a process for non-catalytically removing NO from combustion effluent streams at temperatures from about 1300.degree. K. to 1600.degree. K. by injecting ammonia immediately before or directly into a zone where the combustion effluent is cooling at a rate of at least about 250.degree. K.