| 摘要 |
1. A heat exchanger with fluidized bed firing comprising a sub-floor (36, 36') disposed between an air chamber (50) and a fluidized bed (54), said sub-floor being formed with air passage apertures, heat-exchanger heating surfaces (57) being disposed above the sub-floor (36, 36') and in the fluidized bed (54), characterized in that the sub-floor (36, 36') is lowerable and provided with lowering means (38, 39, 40, 41, 42; 70, 71, 73) and said means are connected to control means (43, 44, 45) so constructed that in the event of any failure of air feed to the fluidized bed (54) the means (38 to 42; 70, 71, 73) lower the sub-floor (36, 36') until the heating surfaces (57) emerge from the fluidized bed. |
