Patent ID: 9676637
Date: 2017-06-13
CPC Classifications: C02F,G01J

Claim:
1. An ultraviolet (UV) irradiation apparatus comprising: a treatment tank that comprises a water supply opening to supply therethrough treated water to be further treated and a water drainage opening to drain therethrough the treated water; a UV irradiation member that is provided inside the treatment tank and irradiates the treated water with UV light when the treated water passes through inside of the treatment tank; a UV sensor that is provided inside the treatment tank and measures a dose of UV irradiation from the UV irradiation member; an air outlet unit that is connected to an air outlet hole provided at a position higher than a horizontal plane passing through the UV sensor and that is provided to release, to outside of the treatment tank, through the air outlet hole, air that accumulates inside the treatment tank when the treated water passes through the inside of the treatment tank; and a measurement unit that measures a vertical position of a water surface of the treated water passing through the inside of the treatment tank, wherein the air outlet unit releases, based on a measurement result from the measurement unit, the air through the air outlet hole before the water surface of the treated water lowers below the horizontal plane passing through the UV sensor.