Patent GB-790746-A (GB)
Title: A process and apparatus for the manufacture of solutions of bactericidal gas in water or aqueous liquid
IPC: C02F1/76
Filed: 1956-08-29
Abstract: 790,746. Mixing fluids in flow. CHLORATOR GES. Aug. 29, 1956 [Aug. 29, 1955], No. 26419/56. Class 86 In a process for the manufacture of a solution of a bactericidal gas in water or aqueous liquid, the liquid while flowing through a closed chamber is mixed with the gas, the amount of which is regulated by the position of the level of the liquid in the chamber. In the apparatus shown in Fig. 1, a pump 6 draws water from a main 1 and supplies it under pressure through an injector 9 to a chamber 7. The water is mixed with chlorine supplied from a container 14 for liquified chlorine through a gas valve 13, the degree of opening of which is controlled by a float 15 acted upon by the chlorine solution. The pressure of the water in the main 1 is lower than the vapour pressure of liquefied chlorine. The solution is drawn off to the main stream 1 through pipe 8. Valves may be provided in the pipes leading to and from the chamber 7. The apparatus shown in Fig. 3 is used for sterilization of water or sewage by chlorine when the amount of liquid to be sterilized is too small to drive an injector. The liquid is mixed with the chlorine in chamber 7 by means of Raschig rings in the gas space of the chamber 7. An obstacle 12, for example, an annular disc, a pilot tube or a slide valve in the main 1 may be provided to assist in maintaining a constant ratio between the amount of liquid flowing through the main 1 and the amount entering pipe 5. Alternatively, a check valve 11 in the pipe 5 and a regulator valve 10 in the pipe 8 may be provided, the degree of opening of the valve 10 being regulated automatically by means of a measuring instrument 22 connected to a regulator 23, the instrument 22 measuring the chlorine ion concentration in the liquid flowing through the main 1. In a modification a pump is provided in the pipe 5 the output of which is automatically controlled by a water meter arranged in the main 1 before the water enters the pipe 5, whereby the ratio between the amount of aqueous solution of chlorine entering the main 1 and the amount of water flowing through the main 1 is kept constant. In the arrangement shown in Fig. 4 the pressure of the liquid in the main stream 1 is greater than the vapour pressure of liquid chlorine. Valves 24, 25 reduce the pressure of the water in branch pipe 28 and pipe 5 respectively. The concentrated mixture of the liquid and gas leaves the chamber 7 through pipe 8 and after joining the liquid in pipe 28 passes through a pressure-increasing pump 27 to rejoin the liquid in the main stream 1. A safety valve 26 is fitted to the chamber 7. Fig. 7 shows another arrangement where the gas in the chamber 14 is liquefied or compressed oxygen. The chamber 7 is connected by a pipe 11 to an electric ozonizer 10 the outlet of which is connected by a pipe 12 with the suction side of the injector 9 whereby a mixture of oxygen and ozone is mixed with water passing through the injector 9 the ozone dissolving in the water. A gas drier (not shown) may be disposed in the pipe 11.