GB886575A - - Google Patents

Abstract

886,575. Mixing liquids. FARBWERKE HOECHST A.G. Jan. 22, 1960 [Jan 22, 1959], No. 2508/60. Class 86. Liquids are mixed intimately, particularly in the production of emulsions, by injecting intermittently one of the liquids, which has been passed through a very fine filter, at a pressure of from 5 to 5000 atmospheres through a nozzle into the other liquid which flows continuously past the nozzle. The intermittent injection may be obtained by using a spring-loaded obturator on the nozzle, which opens only when the pump, e.g. a plunger or diaphragm pump, builds up sufficient pressure on the discharge stroke. As shown, one of the liquids passes from a vessel 1, through a filter 2, to a pump 3 which delivers it to a nozzle 7. The other liquid is supplied from a rotameter 10 to an annular space surrounding the nozzle 7 so that the mixture flows into a tube 9 surmounted by an overflow vessel 14 from which it flows to a collecting vessel 11. Some of the mixture may be recirculated by a pump 12 to the space around the nozzle 7. If the liquid in the vessel 1 is a mixture of immiscible liquids, e.g. oil and water, the homogenerty of the said mixture is maintained by a pump 13 which sucks from the inlet of the pump 3 and re-delivers the mixture to the vessel 1. If the compressibility of the liquid from the vessel 1 is low, it may be necessary to provide a vessel 5 in the high pressure line to prevent a too rapid rise or fall in pressure at the nozzle 7. The passage 8 leading to the tube 9 may be of various shapes according to the liquids being emulsified, it may be of greater diameter than the tube 9 or tapered as shown. The nozzle may be inverted to deliver in contraflow to the other liquid. The liquids may be substances or solutions or mixtures of substances which are liquid at room temperature, or need to be heated or cooled to bring them to liquid form for treatment, or may have endothermic or exothermic reactions, in which case the apparatus is provided with the necessary heating or cooling means. The pressures used and rates of flow depend on the nature of the liquids, but the emulsion remains in the tube 9 for a substantial time, i.e., a maximum of 120 minutes. Examples of processes for mixing various substances are given.