Patent ID: 8552395

Claim:
An ultraviolet irradiation system that sterilizes, disinfects, and inactivates raw water such as city water or underground water, comprising: a plurality of ultraviolet irradiation devices; a plurality of on-off valves that allow one ultraviolet irradiation device of the ultraviolet irradiation devices to be used or allow the plurality of ultraviolet irradiation devices to be connected in series or in parallel and to be used; and a controller configured to control opening and closing of the on-off valves, wherein the ultraviolet irradiation device comprises: a water processing vessel comprising a water supply port into which the raw water flows; an ultraviolet lamp configured to irradiate the raw water that flows in the water processing vessel with ultraviolet rays; a water discharge port from which the raw water irradiated with the ultraviolet rays is discharged; and an ultraviolet sensor configured to measure an amount of ultraviolet rays emitted from the ultraviolet lamp, and wherein the controller is configured to control opening and closing of the on-off valves to connect the plurality of ultraviolet irradiation devices in parallel when an amount of the raw water exceeds a range of a processing capacity of one ultraviolet irradiation device.