| 摘要 |
1429218 Rotary heat exchangers R E CROCKER 23 July 1973 [2 Aug 1972] 35098/73 Heading F4S A rotary heat exchanger used for heat treating liquid or semi-liquid material, e.g. sterilizing sewage sludge, comprises a helically wound coil 46 made by winding a V-shaped strip and disposed between inner and outer concentric cylindrical members 38 and 34 to define inner and outer triangular shaped helical passageways 114 and 116 respectively for the material to be treated. The cylindrical members extend between and are bolted to end plates 30, 32 which are mounted on a rotatable shaft 22. Heating means 49 in the form of an annular chamber supplied with hot gases from an external source (66, Fig. 1) surrounds part of the coil 46. In use the material to be treated enters the heat exchanger via inlet conduits 78, 88 to travel through the heating zone in one direction via inner passageway 114 and then back through the zone in the opposite direction via the outer passageway 116 before finally leaving via outlet conduits 92, 86 and 102, the heated outgoing material serving to preheat the incoming material: an end cap (118, Fig. 4) is provided to reverse the direction of material flow between the passageways 114 and 116. The heating means 49 comprises a stationary U-section cover member 52 surrounding part of the outer cylindrical member 34 and having a radially extending spiral shaped partition 58; rings 50 are provided on the outer surface of the member 34. Hot gases enter the cover member through an inlet opening 62 and leave via an outlet opening (63, Fig. 3). Air or other fluid may be introduced into the material to be treated via an inlet 80 to promote oxidation. |
