| 摘要 |
530,792. Heating air for combustion. BABCOCK & WILCOX, Ltd., and JESSON, W. E. June 19, 1939, No. 17839. [Class 64 (i)] In an air heater in a boiler flue 3, to prevent corrosion of the heater due to condensation from the cooled furnace gases, air is introduced at the last air pass 7 of the counter flow part of the heater only after the air has received heat in a pass 4 over which flow furnace gases at a considerably higher temperature than their exit temperature. The heater may form a U-shaped air path across a U-shaped gas path. The air may flow from the supply conduit into the pass 7 partly directly and partly through the highly heated pass 4, the relative quantities of air being controlled by dampers in the conduit. |
