Patent GB-283887-A (GB)
Title: Catalytic apparatus
IPC: B01J8/06
Filed: 1928-01-07
Abstract: 283,887. Selden Co., (Assignees of Jacger, A. O.). Jan. 19, 1927, [Convention date]. Catalytic apparatus.-A catalytic converter system comprising at least one converter which is cooled by transfer of heat through a partition separating the catalyst from the incoming gas, the cooling being sufficient to enable it to operate at rates largely in excess of normal commercial output, followed by at least one converter of much less effective cooling capacity, with or without coolers or heat exchangers situated between the two stages. Instead of a single converter a series of converters of progressively decreasing cooling capacity may be used in either stage or both stages. The powerfully cooled converters are preferably designed so that the cooling effect is proportional to the rate of gas flow; this result may be obtained by passing either a part or the whole of the incoming gas in single or double counterflow through heat-exchangers embedded in the catalyst before passing it through the catalyst. Auxiliary cooling by liquids may also be employed. A part of the gas issuing from the powerfully cooled converter may be re-circulated therein, if necessary after cooling or after readjustment of its composition. Fig. 1 illustrates a typical embodiment of the invention. The converter I is cooled by passage of incoming gas through the tubes 8, 7; more gas may be directly admitted at 12. The second converter II is a two-layer Grillo type converter, Heat-exchangers III, IV use the incoming gas to cool the effluents from I and II respectively; arrangements for bye-passing them are provided. The exchanger III may be replaced by a cooler of adjustable capacity as shown at III, Fig. 14, or the necessary cooling may be effected in the lower space of I by extending the tubes 7, 8 into it. In another modification the converter. I is inverted and contains in its upper part a separate layer of uncooled catalyst similar to the layers in converter II. The Specification describes many other forms of gas-cooled converter which may replace that shown in Fig. 1; among these are the Tentelew, Audianne, and Knietsch types. Fig. 6 shows a modified Tentelew type with double counterflow cooling. Fig. 8 shows in plan a type similar in principle to Fig. 1 but having concentric annular passages. The gas flows down through the spaces a, up through b, and down through the catalyst c. Fig. 14 shows at I a converter having sealed tubes 140 containing liquid embedded in the catalyst and projecting into the gas entering by 142. The evaporation of liquid in the lower part and its condensation in the upper part of these tubes assists in the cooling of the catalyst. In a modification the upper parts of the tube project into a separate space through which a blast of cold air is forced. A second portion of gas enters at 26 from the heat exchanger IV and cools the catalyst by double counterflow. Part of the gas leaving this converter is re-circulated by the blower 148 to the pipe 26, optionally with addition of hot or cold, active or inert gas at 150. The invention is applicable to many kinds of catalytic reaction, including reduction, dehydration, hydrogenation, dehydrogenation, halogenation, oxidation, condensation. The production of sulphur trioxide, methanol, oxides of nitrogen, the treatment of water gas, and the synthesis of ammonia are mentioned. Many instances of the oxidation of organic compounds and of the types of reaction are also enumerated. According to the Specification as open to inspection under Sect. 91 (3) (a) the powerfully cooled converter may be cooled by means other than conduction through a partition to the reaction gas. This subject-matter does not appear in the Stpecincation as accepted.