Low-emission swirling-type furnace

摘要

PCT No. PCT/RU95/00282 Sec. 371 Date Aug. 28, 1996 Sec. 102(e) Date Aug. 28, 1996 PCT Filed Dec. 26, 1995 PCT Pub. No. WO96/21125 PCT Pub. Date Jul. 11, 1996The low-emission swirling-type furnace is designed to burn organic fuel and it can be most advantegeously used for dust combustion. A low-emission swirling-type furnace, according to the invention, comprises a combustion chamber (1) with a prismatic dry-bottom hopper (5) having a slot mouth, and an undergrate blast inlet means (7) disposed thereunder. The furnace includes at least one burner (2) formed by at least a pair of ducts (2a,2b ) lying one above the other and intended for supplying the air-fuel mixture. The ducts (2a, 2b) are each provided with a device (3, 4) for controlling the "air/fuel" ratio, ensuring such a ratio between the amount of air and the amount of fuel in each of the ducts (2a,2b ) that for the overlying duct (2a), this ratio turns out to be invariably higher than for the underlying duct (2b). The longitudinal axes of the ducts (2a, 2b) are preferably so inclined that the angle between the longitudinal axis of the duct (2b) and the projection of this axis onto the furnace wall for an underlying duct is less than that for the overlying duct (2a). Furthermore, the furnace may also be provided with a means (8) for supplying the fuel of a specific size composition into each duct. During operating of such furnace, three functional zones are generated in the heating volume, namely: the ignition and active combustion zone, the reduction zone, and the reburning zone. This results in a reduced discharge of nitrogen oxides, along with an economical performance of the furnace.