GB113105A - Apparatus for and Processes relating to Purifying or Treating Water or Sewage or other Liquids. - Google Patents

Abstract

113,105. Wallace, C. F., and Tiernan, M. F. Nov. 14, 1916 Fluid-actuated valves.-In apparatus for treating liquids with gases, and particularly for treating water or sewage with chlorine, the flow of gas is maintained proportional to the flow of liquid by causing it to pass a constriction, such as a control valve 67, Figs. 1 and 2, which is described in Specification 113,106, whereby its pressure is reduced, and by rendering the drop in pressure, by means of a differential pressure device 33 acting upon a valve 101 through which the gas is supplied, equal to a pressure difference dependent upon the flow of liquid, such as that obtained by a Venturi tube. In the form of apparatus shown in Fig. 1, gas is supplied from cylinders 27, 28 through a valve 31 operated by an electromagnet to cut off one cylinder when it becomes empty and to connect up the other. After passing the constriction 67 it flowe through a measuring and indicating device S, and into a casing 25<a> in the liquid main where it is diffused into the liquid by a diffuser 158. In the differential pressure device shown in Fig. 2 the gas passes through a, passage 99 to a valve 101 and then by a passage 103 to a chamber 85 closed by a diaphragm 93 and by a pipe 66 to the constriction 67. The gas at reduced pressure after passing the constriction has access by a pipe 97 to a diaphragm 91. A sealed fluid between the diaphragms 91, 93 and able to pass from one to the other through a passage 98, transmits the reduced gas pressure to the left side of the diaphragm 93, which is therefore subject to a pressure equal to the drop in pressure of the gas across the constriction 67. A diaphragm 92 is subjected on opposite sides to the pressures transmitted by pipes 94, 95, Fig. 1, connected to a Venturi tube in the liquid main. The diaphragms 92, 93 act in opposite directions on the stem 109 of the valve 101. The aperture for the passage of the valve-actuating stem in the wall which separates the chambers between the diaphragms 92, 93 is sealed by an elastic tube 114 connected at one end to the wall and at the other to the stem, and the tube is supported against collapse by helical springs outside and inside. According to a modification, the liquid passes through a chamber wherein its height is dependent upon its rate of flow, and a float therein transmits pressure by a rod 178, Fig. 6, to a diaphragm 180 which transmits the pressure through a liquid to one side of the diaphragm 92, Fig. 2. In this case the other side of the diaphragm 92 is open to atmospheric pressure and the diaphragm 91 is dispensed with. According to another modification, the liquid to be treated is delivered by pumps, and smaller pumps pass a proportional volume of the liquid through the Venturi tube shown in Fig. 1.