Patent ID: 6302039
Filing Date: 2001-10-16
Classification: F23C,F23G,F23L,F23M

Abstract:
A method of introducing a portion of the combustion air, or some portion of recycled flue gas in place of all, or some of the said portion of the combustion air, at any elevation into: a furnace firing black liquor from the kraft recovery process, a furnace firing black liquor from the soda process, a furnace firing black liquor from the sodium-based sulphite process, a furnace firing black liquor from the closed-cycle CTMP process, a furnace firing liquor from the magnesium-based sulphite process, a furnace firing liquor from the ammonium-based sulphite process, and furnaces of boilers burning biomass, wood waste or other solid fuel, said method comprising:a. introducing air, or air and recycled flue gas, at the particular elevation as jets from two, opposite, first and second, hereinafter-called ""active"", sides of an inclined plane which is bounded, respectively, by the first and second, hereinafter-called ""active"", walls of the interior of the furnace and by the third and fourth, hereinafter-called ""inactive"", walls of the interior of the furnace, such that the jets are arranged in a partially-interlaced pattern of large and small jets, wherein each large jet is opposite a small jet originating from the opposite wall, and the jets are arranged small/large/small/large, etc., in an alternating pattern along the length of each of the said two active sides of the said plane;b. distributing the flow of said air, or said air and said recycled flue gas, such that the total flow from each of the two opposite ""active"" sides of the said plane is more or less equal;c. directing the said jets in a fully-opposed or partly-opposed juxtaposition relative to the said plane;d. the said plane is essentially flat, or, one first side of the said plane is curved, or, both first and second sides of the said plane are curved.