Patent GB-854020-A (GB)
Title: Apparatus for producing and/or distributing a mixture of at least one chemical substance with a main stream of liquid, chiefly for treating and disinfecting water
IPC: C02F1/68
Filed: 1957-03-25
Abstract: 854,020. Purifying water. SOC. NOUVELLE PICA, [formerly PROCEDES INDUSTRIELS ET CHARBONS ACTIFS]. March 25, 1957 [March 29, 1956], No. 9723/57. Class 46. [Also in Group II] Apparatus for blending with a liquid a predetermined proportion of one or more chemicals, and especially for treating water with a chlorine-containing sterilizing agent such as eau de Javelle (chlorinated caustic potash solution), comprises (1) a receptacle provided with means for supplying the liquid thereto, (2) a reservoir for one or more chemicals located within the receptacle, (3) a device mounted within the receptacle and comprising two compartments into which the liquid is alternately charged, the device being adapted to rock by gravity when one or other of the compartments has received a predetermined quantity of the liquid and the rocking movement serving (a) to discharge the liquid from one compartment into a body of liquid at the bottom of the receptacle and to bring the other compartment into a position where it in turn receives the liquid, (b) to raise chemical from the reservoir and to discharge it into one or other of the compartments and (c) to agitate the body of liquid, (4) a float-controlled valve whereby the liquid inlet is regulated to ensure that the level of liquid in the bottom of the receptacle is maintained between predetermined limits and (5) means for drawing off liquid from the bottom of the receptacle, the draw-off means being such that the liquid cannot be drawn off when it falls below the predetermined low level and such that the liquid is drawn off at a height which is less than half the height of the predetermined low level. In Fig. 1, water is admitted through pipe 3 into chamber 1, which contains a reservoir of eau de Javelle, the ends of the reservoir being shown at 8a and 8b. Water from pipe 3 passes through distributing pipe 19 and falls into compartment 14a or 14b of rocking member 6, which is mounted on spindle 9. When compartment 14a or 14b is full, rocking member 6 tips and the contents of the compartment are discharged into the body of liquid at the bottom of chamber 1. Rocking member 6 is also provided with pipettes 7a and 7b, arranged so that a measured quantity of eau de Javelle is discharged into compartment 14a or 14b every time the rocking member tips. Furthermore, blade 16 stirs the body of liquid at the bottom of chamber 1 every time the rocking member tips. Stops 15a, 15b are provided to limit the movement of the rocking member, while the input of water is adjusted by a valve (within body 18) under the control of ball float 21. Treated water is withdrawn through channel 5, while an overflow pipe 26 is also provided. Vent 24 assists in breaking the siphon of water through channel 5 when the level falls too low in the body of liquid at the bottom of chamber 1. Alternative arrangements for the discharge of water from chamber 1 are described. Also the modification of the apparatus to dose the water with two chemicals (e.g. eau de Javelle for sterilizing and sodium metaphosphate solution for softening) is described.