Patent GB-869468-A (GB)
Title: Improvements in the preparation of aqueous solutions of salt or salt and vinegar
IPC: A23B4/02
Filed: 1957-06-11
Abstract: 869,468. Mixing liquids in flow. BACHERT, A., and BACHERT, W., [trading as BACHERT & SOHNE, FR.]. June 11, 1957 [June 9, 1956], No. 18426/57. Class 86 [Also in Group XXVIII] Apparatus for the continuous preparation of salt solutions of any desired concentration comprises, a vessel 13, Fig. 1, in which a saturated salt solution is continuously prepared, and a water pressure-operated doublemembrane pump having a known control valve 9, to draw the saturated solution from the vessel 13 and pass it under pressure to a mixing device 35 through a pipe 25, air chamber 27, valves 30, 31 and a pipe 33, the mixing device 35 being supplied with water, flowing at selectable rates through a pipe 57 valves 58, 59 and a pipe 50, and the final salt solution being discharged from the mixing device through a pipe 42 to a measuring cylinder 61 and thence by a pipe 66 to the point of application of the solution. The water pipe 57 is connected to a water supply pipe 1 which is also connected through a valve 3 with the pump. The pump comprises two chambers each comprised of two parts 6, 7 and rubber membranes 4 and 5 interconnected by a shaft 8. The chamber spaces 10, 11 of the pump are alternately connectible through the control valve 9 with the valve 3 and with a discharge pipe 12. The chamber spaces 23, 24 of the pump are alternately connectible to the suction pipe 21 and the discharge pipe 22. Assuming, for example, that the valve 9 has connected the valve 3 with the space 10, the membrane 4 expels saturated salt solution from the chamber 23 to the pipe 25 whilst the membrane 5 expels water from the space 11 to the pipe 12 and draws saturated salt solution into the space 24 from the pipe 21. At the end of the movement of the membrane 4 to the right, the valve 9 is changed over automatically and the space 11 is then connected to the valve 3 so that the membranes 4, 5 move to the left and saturated salt solution is discharged from the space 24 to the pipe 25. A constant level of water is maintained in the vessel 13 by means of a float valve 14 at the end of the pipe 12; should the valve 14 close, then excess water is passed to a pipe 16 and channel 17. Saturated salt solution is drawn into the pipe 21 from a funnel 19 provided with a filter 20 to prevent entry of undissolved salt 18. Referring to Fig. 2, the mixing device 35 comprises two chambers 48, 51 separated by a partition 37 provided with an aperture 43. A disc 44 is held against the partition and rotatable relative thereto by means of a shaft 45 and handwheel 54. A number of holes of different sizes (e.g. 47 inches) in the disc are selectively alignable with the aperture 43. The saturated salt solution enters the chamber 51 at 39; water enters the chamber 48 at 49 and the diluted solution leaves the chamber 51 at 41. In another embodiment described with reference to Fig. 4 (not shown) a mixing device in the form of a rectangular chamber is inserted in the suction pipe 21 and water and concentrated vinegar are supplied to the chamber through pipes under constant head. The pipes for the three constituents are each provided. within the chamber, with interchangeable caps each having a different size aperture therein, whereby the proportions of the constituents may be varied. In this embodiment the caps may be omitted and the pipes then controlled by valves.