No-plume device

Claim 1

Apparatus for treating stack gases resulting from combustion of high sulphur containing fuel, and which contain substantial content of SO 3 , comprising; (a) a stack for carrying the combustion gases upwardly for discharge into the atmosphere, said gases flowing at velocity V 1 ; (b) means for injecting into said flow of combustion gases at least one jet of diluent gas, at a velocity V 2 , where V 2 is substantially greater than V 1 ; (c) the injection point being at a selected distance upstream of the top of said stack; (d) said at least one jet of diluent gas being directed into said stream of combustion gas to provide maximum mixing of said diluent and combustion gases; whereby the concentration of SO 3 is reduced and the dew point depressed below the expected temperature of the combined gas flow when the effluent reaches the atmosphere; and including (e) a plurality of short small diameter pipes sealed into the wall of said stack, said pipes directed radailly inwardly and upwardly, and circumferentially spaced; (f) a cylindrical plenum on the outside of said stack and enclosing said short pipes, said plenum and pipes positioned a selected distance below the top of said stack; (g) means to supply diluent gas to said plenum at a pressure P 2 such that the jet velocity of diluent gas V 2 in said pipes will be substantially greater than the velocity V 1 of said combustion gas rising in said stack.