TWOOLAYER TYPE LOWWPOLLUTION COMBUSTION DEVICE

摘要

PURPOSE:To reduce NOx without lowering combustion efficiency by operating combustion in two stages of reducing layer and oxidizing layer. CONSTITUTION:Nitrogen compounds blown into reducing layer 8 is decomposed into chemically very stable N2 under the reducing atmosphere, and it hardly becomes NOx in oxidizing layer 13 of the next stage. On the other hand, in this reducing atmosphere, soot, CO, H2 and other hydrocarbons are produced, and depending upon the kind of fuel, cokes, chars and other carbides are formed inside the layer. But these gases, which have not been burned, together with combustion- produced gases, are burned completely by air from secondary air nozzle 12 in oxidizing layer 13 on the down stream side. On the other hand, solid particles, such as cokes, remaining in reducing layer 8 are taken out by take-out pipe 9; and they are transported to oxidizing layer 13, via blow pipe 10, by air from pipe 7, and are burned completely in oxidizing layer 13.