GB305163A - A method of and apparatus for selectively discharging liquids according to their electric conductivity, particularly applicable for selecting pure water from water of condensation and returning it to boilers - Google Patents

Abstract

305,163. Papeteries Navarre. Feb. 1, 1928, [Convention date]. Feedwater, supplying and controlling.-In apparatus for returning to a boiler water of condensation from steam heaters used in chemical works, such as cellulose factories, valves operated by servomotors automatically control the collection and return of pure water and the rejection of water accidentally contaminated by leakages in the heating system. The valve 29 controlling the discharge of water from the collecting vessel 1 either to the boiler 45 or through the outlet 46 to waste is operated by a servomotor 18 controlled by a solenoid 37 in a circuit the current in which is shunted across plates 3, 4 when the water in the collecting vessel is impure and therefore conductive. The valve 25 controlling the entrance of water to the vessel and the discharge therefrom under steam pressure through a pipe leading to the valve 29 is operated by a servomotor 17 controlled by a solenoid 36 in a circuit containing contacts 39, which are closed when a float 8 in the vessel reaches its highest position. The valve 25 is then open to discharge, and the water is forced out of the vessel by steam admitted through a piston valve 11 operated by a rod connected to the stem of the valve 25. Oil is supplied to the servomotors by a pump 35. In case of failure of current or oil pressure, springs 26, 27 set the valve 25 at an intermediate position, and a spring 28 sets the valve 29 to open the waste outlet 46. The movements of the valve are registered by recording instruments 30, 31.