Patent GB-259985-A (GB)
Title: Improvements in or relating to absorption refrigerating machines
IPC: F25B15/10
Filed: 1926-10-15
Abstract: 259,985. Siemens - Schuckertwerke Ges. Oct. 17, 1925, [Convention date]. Refrigerating, absorption machines and processes for.-In a continuous-cycle, system of the kind wherein gas expelled from the solution in a, heated generator 19 lifts the liquid through a riser pipe 21 into a gas-separating chamber 22, as described in Specifications 251,251 and 250,593, the expelled gas exchanges heat with the liquor in a vessel 15, at a lower level than the separating-chamber, in order to deprive the gas of any solvent vapour. The cold is produced bv the evolution of the refrigerant gas from cold rich solution in a vessel 1, and a neutral gas such as air or nitrogen circulates between the absorber 8 and the cold generator or evaporator 1. The system may operate with ammonia and water and at a pressure of about one atmosphere. The weak liquor flows from the gas separating chamber 22 through a pipe 10 to the top of the absorber 8, which is cooled by a coil 9, and the rich liquor returns to the generator 19 by way of a U-tube 11, 12, pipes 13 and 14 and the interchanger 15. A sludge chamber 46 in the pipes 13, 14 serves also to prevent liquid being forced out of the pipes 13, 14 when the pressure in the absorber is greater than that in the interchanger during a pause in the working of the machine. The interchanger shown provides for direct contact between the gas and the liquor, the gas entering at the bottom by a pipe 23 and the rich liquor being distributed over spaced plates &c. The lower part of the interchanger forms a reservoir 25 for liquor, which passes to the generator by pipes 17, 18 and a trap or buffer chamber 47. The gas leaves the interchanger by a pipe 24 and alter passing through vessels 31, 33 and pipe 34 enters a mixing vessel 30. From this vessel gas and liquid ascend a pipe 35 to a reabsorber 36, which is cooled by a coil 37. A pipe 38 connected with the gas space of the reabsorber leads any unabsorbed gas to an intermediate chamber 27, while the cooled reconstituted strong liquor flows from the reabsorber through a pipe 2 to the top of the evaporator 1. The evaporator is fitted with absorbent apertured baffles 3 over which the strong liquor descends, the weakened liquor flowing down a pipe 26 to the intermediate vessel 27 and thence by a pipe 29 to the mixing vessel 30. An overflow pipe 45 from the intermediate vessel 27 conveys surplus liquor to the top of the interchanger 15, where it is in a condition to assist in the rectification of solvent vapour from the hot expelled gas. A forced circulation of the inert gas and gas mixture between the absorber 8 and evaporator 1 is effected by an injector nozzle 43 supplied with high pressure gas from the vessel 33 by way of a pipe 40. vessel 41, and pipe 42. The vessel 41 is cooled by the pipe 6 that conveys the gas mixture to the absorber, and any liquid separated in the vessel drains into the mixing vessel 30. Any gas not absorbed in the reabsorber 36 is led from the intermediate vessel 27 to the absorber 8 by way of a pipe 39 and trap 48 connected to the limb 12 of the U-tube, which limb is of such a width that the gas bubbles cannot eject liquid therefrom. A modification is described in which the hot -expelled gas is rectified by passing it over the surface of a coil conveying the strong liquor from the absorber to the generator. Any refrigerant gas generated from the liquor as the result of this heat interchange is led into the gas flow pipe from the interchanger.