Patent GB-504374-A (GB)
Title: Improvements in or relating to absorption refrigerating apparatus
IPC: F25B15/10
Filed: 1937-08-20
Abstract: 504,374. Refrigerating. HOOVER, Ltd. (Hoover Co.) Aug. 20, 1937, No. 22899. [Class 29] Absorption systems.-Liquefied refrigerant or absorption solution is circulated upwards or horizontally through a conduit by the blowing or dragging action of inert gas circulated through the conduit at high velocity by a power driven fan. Preferably a heavy gas such as nitrogen is used, although hydrogen at a much higher velocity, or propane or other condensing pressure - equalizing vapour may be used. In the system shown in Fig. 1, and comprising the usual generator B, analyzer D, rectifier R and condenser C, the evaporator E comprises a sinuous tube bent to form three shelf - like horizontal stretches 25, 26, 27. The condensed refrigerant is supplied through a pipe 12 to the conduit 35 conveying inert gas from the gas heat-exchanger 14 to the tubular part 31 of the lowest stretch, and the liquid is lifted through the bend 36 to the middle stretch; then through bend 37 to the upper stretch, and finally through a riser 38 to a finned chamber 28 constituting a cooling element for the storage space of a cabinet. The gas mixture returns through the exchanger 14 to the lower end of the absorber A. A portion of the gas delivered by the fan F is directed through pipe 23 to the weak liqour pipe 22 to provide a gas lift for the liquor. A drain conduit 24 for unused refrigerant extends from the evaporator element 32 to the strong liquor pipe 19, and its mouth opens into the top of the bore of tube 32 so that a pool of liquid refrigerant may be retained in the evaporator to facilitate starting up. The condensed refrigerant may be supplied to the riser between the lowest and middle stretches of the evaporator coil, or, as shown in Fig. 4, to the back end of the middle stretch. A conduit 45 extends as a seal pipe from the element 28 to the middle stretch, with a further. seal pipe 46 connecting it to the inert gas inlet branch 35. At starting of the operation the conduit 45 is open to flow of gas, which is divided, and due to the reduced velocity of gas flow in the evaporator the condensate is divided and flows in two streams until the seal pipe 46 fills up. A dam 47 provides a pool of refrigerant in the middle stretch. In the evaporator shown in Fig. 6, the stretches of the coil are connected by liquid refrigerant pipes 65, 67, 68, and a gas lift in the pipe 64 is provided by a gas pressure conduit 66, in addition to the main gas inlet pipe 63. An application of the liquid-gas flow method to the absorption liquid is shown in Fig. 9. Weak liquor enters a vessel 73 and is entrained by the gas mixture from the evaporator E through an auxiliary absorber 98, from which it is supplied through a gas separator 99 and pipe 102 to the main absorber 101. The evaporator may operate as previously described or the liquid may flow therethrough under gravity. In another system with a single absorber the gas delivery pipe from the fan may terminate in a nozzle entraining liquor from a reservoir into the lower end of the absorber. The invention may be employed in the systems set forth in Specifications 501,398 and 501,399.