Improvements in liquid irradiating apparatus

摘要

Apparatus for irradiating liquids comprises an airtight container having an apertured wall, a vertical partition within the container forming a liquid confining dam, and a closure for the aperture, on which closure is mounted, for passage through the aperture, an elongated source of germicidal rays, e.g. an ultra-violet lamp, and means for supporting such source above the upper edge of the partition and parallel therewith. The apparatus of Figs. 1 and 2 comprises an elongated cylindrical tank 1, capable of withstanding pressures above atmospheric, having a vertical partition 2, an inlet 3 and an outlet 4 for water, and an opening 5; round the opening is a housing 6 to which is secured a header 7, and mounted on the header are lamp sockets 8, an ultra-violet lamp 10 and a reflector 9 therefore. Water is pumped by a pump 19, driven by an electric motor 20, through a conduit 17 and a diffuser 3a into the tank at the inlet side of the partition 2, and is subjected, on overflowing as a thin sheet S into the outlet side of the partition, to ultra-violet light from the lamp 10; when the water here reaches the level Ca the pressure of air entrapped in the tank causes a pressure-responsive switch 27 to stop the motor 20 and the pump 19; on withdrawing water from the outlet 4 to the extent that the level Cb is reached, reduction of air pressure in the tank causes operation of a pressure-responsive switch 26 to energize the motor 20 and set the pump 19 in action. In order to prevent waterlogging of the tank by gradual absorption of entrapped air by water passing through the tank, a float valve 31 is arranged to open an air valve 30 each time the water reaches the level Ca, and thus admit air on the inlet side of the pump 19; fall of the water level to Cc causes closure of the air valve 30.