| 摘要 |
1,074,599. Treating exhaust gases. WALKER MANUFACTURING CO. June 22, 1964 [June 25, 1963], No. 25690/64. Heading F1B. An exhaust purifying system comprises a catalytic reactor 11, Fig. 1, in which all the exhaust gases pass through the catalyst bed 92 and upstream thereof a catalytic reactor 7 in which only a portion, or more, of the gases flow through the catalytic bed 67, the reactor 7 reducing the amount of combustible constituents in the exhaust gases to prevent overheating of the reactor 11. The catalyst is supported by perforated shells 29, 43, and some of the gases flow through a central passage 29 and an outer annular passage 53 whilst restrictions 75 in the passage 29 cause a portion of the gases to flow from passage 29 through the bed 67 to the outer passage 53 from which the gases flow to the outlet 27. The shell 43 is supported by projections 45 on the outer casing 17 which is insulated by layers 19 of asbestos and the central pipe 29 is welded at one end to a flanged member 35 and is a sliding fit at the other end in a member 35, permitting expansion. In a modification the restrictions 75 are omitted so that the gases merely flow along the sides of the catalyst bed 67 and in a further modification the outer passage 53 is omitted. In the reactor 11 the central passage 83 is closed by a plate 85 so that all of the gases flow outwardly through the bed 92 to the outlet chamber 107. The central passage 83 may taper towards the outlet end. In the reactor (161) of Fig. 4 (not shown) a portion of the gases flows straight through the central passage (169) whilst the remainder flows through apertures (171) into catalyst bed (175) and rejoins the main stream through apertures (173), a projection (177), producing a Venturi effect adjacent the apertures (173) to produce the flow through the catalyst. A multi-component system, Fig. 7 (not shown) comprises a bank of straight-through catalytic reactors 191, reactors 7, 7', similar to reactor 7 of Fig. 1, and a bank of reactors 161 as shown in Fig. 4, downstream of which is situated a flow-through reactor such as 11, Fig. 1. |
