Patent GB-627701-A (GB)
Title: Improvements in apparatus for mixing fluids
IPC: B01F3/08
Filed: 1946-07-01
Abstract: 627,701. Mixing fluids in flow. WALLACE & TIERNAN, Ltd., and WHITLOCK, E. A. July 1, 1946, No. 19636. [Class 86] In an apparatus for mixing fluids in fixed proportions and at a variable rate, the fluids pass continuously through the same or separate chambers maintained under partial vacuum, the rate of flow being dependant solely on the pressure in the chamber or chambers and the latter being in communication with a control point or chamber at which the pressure may be varied in accordance with the rate of flow desired. The pressure may be varied automatically either by a converter influenced by changes in the now of a stream into which the mixed fluids are to be delivered or by a variable aspirator controlled by electromagnetic valves, or manually. In the apparatus shown, for mixing chlorine with ferrous sulphate solution to produce chlorinated copperas, sulphate solution from a source 11 and chlorine gas from a source 12 are drawn into a twostage injector 13 supplied with water under pressure at 58. The solution from a tank 15 passes by way of a weir 22 in a vacuum chamber 19 to a water tank 24 and is drawn mixed with water, by the pipe 30 to the stage 31 of the injector. Chlorine gas under negative pressure in the bell 33 passes by a pipe 44 to a vacuum chamber 43 in which negative pressure is produced by the connection 42 to the second stage of the injector. The degree of vacuum in the chambers 19 and 43 is controlled by connections to a pressure control chamber 21 which is connected at 57 to the automatic or manual means for controlling negative pressure therein. The chamber 21 is connected to the chamber 19 directly by a pipe 20, and to the chamber 43 indirectly by a U-tube 48, 49, the lower limb 47 of which is connected by a pipe 46 to the tray 36 of the bell 33, in which a constant water level is maintained. The chamber 21 has also an overflow pipe 50 and an aspirator pipe 52. The apparatus is adjusted so that the head X between the tops of the pipes 42 and 50 equals the head Y between the levels of water in the bell 33 and tray 36, the pressure controller connected at 57 is set to allow the desired degree of vacuum to be built up in 21, and a needle-valve 26 is set to fix the proportion of sulphate solution to chlorine. When the injector is started with atmospheric pressure in 21, water alone is drawn in through the pipe 30 and water and some chlorine through the pipe 42. The head in pipe 46 causes water to flow through the chamber 21. Some flows down the pipe 52, aspirating air from the chamber 21 and so lowering the pressure therein. This lowered pressure is applied in the chamber 19 so that sulphate solution flows over the weir, into the tank 24, and then to the injector stage 31, and is applied indirectly to the chamber 43 so that more chlorine is drawn in at the stage 41. In a modification, the solution and gas pass to a single chamber which is connected to a single stage injector and in which the degree of vacuum is adjustable by means of a U-tube with flexible arms which can be moved to vary the head in the U-tube. Specifications 627,748, [Group XXIX], and 627,752 and U.S.A. Specification 1,762,706 are referred to and the Provisional Specification refers to Specification 504,415, [Group XXIX].