A system for disinfecting fluid includes a plurality of fluid reactors. Each of the fluid reactors includes at least one UVC LED. The UVC LED includes an LED chip configured to emit UVC radiation and a package coupled with the LED chip. The LED chip has a top surface that defines a chip top surface area. The top surface is formed from a semiconductor material having an index of refraction. The fluid reactor has at least one wall that defines a chamber configured to contain the fluid. The at least one wall has an aperture configured to receive UVC radiation into the chamber. The aperture extends through the at least one wall. The aperture has an aperture area that is (1) smaller than a top surface area of the package and (2) equal to or larger than the chip top surface area.

A drinking water treatment system is disclosed. The system includes an ultraviolet (UV) light source and an adsorption medium positioned downstream of the UV light source. The UV light activates residual chlorine in water. The adsorption medium is configured to adsorb any remaining free chlorine from the water. Drinking water treatment systems are disclosed for point-of-use (POU) applications, such as tap-mounted countertop, under-counter, and/or commercial bottling applications, and for point-of-entry (POE).

A fluid sterilizer of an embodiment includes a processing chamber, a light source unit, and a supply flow path. The processing chamber processes a fluid. The light source unit has a light source, a cooling block, and a medium flow path. The light source irradiates the processing chamber with ultraviolet rays. The cooling block cools the light source. The medium flow path is provided inside the cooling block, and a cooling medium flows therein. The supply flow path connects the medium flow path and the processing chamber to each other, and supplies the cooling medium flowing through the medium flow path to the processing chamber as the fluid.

The invention relates to the mitigation of harmful water-borne bacteria such as cyanobacteria. Multiple apparatus are described. One apparatus can apply at least one of UVC irradiation, microbubbles and ultrasonic sound to mitigate the harmful water-borne bacteria. Methods of mitigation of the harmful bacteria are described that do not involve the application of chemicals.

A UV reactor for disinfecting water. The UV reactor may include a cooling chamber in which heat from a UV source may be transferred to the water flowing through the UV reactor. The UV reactor may include driver circuitry operable to determine status information, such as health, of the UV source. The UV reactor may include a gas discharge path operable to substantially prevent accumulation of gas within a water treatment chamber.

Photocatalytic water treatment methods that can be particularly beneficial in degradation of PFAS and reactors and reactor systems that can be useful in carrying out the PFAS degradation protocols are described. Methods utilize bismuth phosphate-based semiconductors as catalysts in particulate or other effective high-surface area water-contacting form. The catalysts can be excited by UV light to induce reduction reactions that degrade or transform PFAS contaminants in the water. Reactor systems include multiple reactors in series and/or parallel. Each reactor includes mixers to encourage turbulent flow within the reactor, control of which is isolated from residence time control within the reactor. The reactors include a light source to deliver about 200 W/L or less of activating radiation emission to the internal volume of the reactor, providing a highly efficient photocatalytic reaction system.

A water treatment system includes a water passage, a magnet and a hydroxyl radical generator. Water flows through the water passage. The magnet is adjacent to the water passage and produces a magnetic field in the water passage, The hydroxyl radical generator generates hydroxyl radicals in the water in the water passage. A water treatment method includes the steps of providing a water passage, producing a magnetic field in the water passage, flowing water through the magnetic field and generating, while the water is in the magnetic field, hydroxyl radicals in the water. The water can be recirculated through the water passage a number of times.

A sterilization apparatus includes a light source unit for emitting light to a sterilization region for sterilizing a target particle, a power supply unit for supplying power to the light source unit, and a photodiode unit for sensing the light from the light source unit. The photodiode unit is driven by the light from the light source unit.

A water treatment method includes: calculating a total amount of ions contained in a total amount of an aqueous solution introduced into a first tank; when the calculated total amount of ions is greater than a first threshold value, introducing part of slurry in the first tank into a second tank; introducing, with an introducing unit, one of a marker molecule and a stain into the second tank; irradiating, from a second light source, the second tank with visible light; detecting, with a detector, first intensity of the visible light having transmitted through the second tank; and outputting, when the activity of photocatalytic particles calculated based on the first intensity is equal to or smaller than a second threshold value, information prompting replacement of the photocatalytic particles, an instruction of recovering the activity of the photocatalytic particles, or information indicative of deterioration of the photocatalytic particles.

A fluid sterilization apparatus includes: a flow passage tube in which a processing passage where a passing fluid is sterilized is formed; a first light source that irradiates the processing passage with ultraviolet light; an inflow passage formed in a direction that intersects an outer circumferential surface of the flow passage tube; and a communication passage that causes the inflow passage to communicate with the processing passage. The communication passage has a narrow passage in the middle of a path from the inflow passage toward an opening of a first end, the narrow passage being narrower than a passage toward the inflow passage.