WO2025032422A1 - Uv fluid treatment system with light source assemblies including intensity sensors and methods of evaluating light source assemblies - Google Patents

Abstract

A fluid treatment system for treating a fluid with UV light and a method of evaluating a condition of at least one light source assembly in the system. The system includes a reactor including a treatment chamber for receiving fluid flow, first and second light source assemblies respectively including first and second arrays of LEDs that face each other in the treatment chamber and can emit UV light to treat the fluid, and first and second intensity sensors that can measure an intensity of UV light incident thereon. The method includes measuring an intensity of UV light in a state in which one of the first and second arrays of LEDs is powered on and the power to the other array of LEDs is temporarily modulated, and determining whether the intensity of UV light is different from a predetermined value.

Description

UV FLUID TREATMENT SYSTEM WITH LIGHT SOURCE ASSEMBLIES INCLUDING INTENSITY SENSORS AND METHODS OF EVALUATING LIGHT SOURCE ASSEMBLIES

CROSS-REFERENCE TO RELATED APPLICATIONS

[0000] This application claims the benefit of U.S. Provisional Application No. 63/531,646, filed August 9, 2023.

BACKGROUND

[0001] Disinfection of water is critical to ensure water quality. Water sources can be contaminated with pathogens, such as bacteria, viruses, fungi, algae, molds, and yeasts, making the water unsafe for consumption by humans and animals. One way of disinfecting water is by ultraviolet (UV) radiation treatment, in which water is irradiated with UV light. UV radiation damages the DNA, RNA, and protein in pathogens, and inactivates them, making the water safe for use and consumption. UV radiation treatment can be used in residential, municipal, commercial, and industrial water systems. Conventional UV radiation treatment systems include a reactor including a treatment chamber through which fluid flows and a UV light source arranged to emit UV radiation into the fluid flowing through the chamber for disinfection, sterilization, purification, and the like.

[0002] UV fluid treatment systems may include an intensity sensor for measuring the intensity of light emitted by the UV light source. For example, the German DVGW organization prescribes the design of a dedicated intensity sensor. However, the intensity sensor requires a dedicated module including a housing, window, and seals that can cause reliability issues and increase costs. For example, during use, the sensor module may become fouled with foreign materials that may block UV light emitted by the UV light source, thereby interfering with the accuracy of the intensity measurements. Example: US8859987B2.

SUMMARY

[0003] The present disclosure provides a fluid treatment system for treating a fluid with UV light that can overcome the above drawbacks. The fluid treatment system includes a reactor including a treatment chamber for receiving a flow of fluid, first and second light source assemblies respectively including first and second arrays of light-emitting diodes (LEDs) that can emit UV light into the treatment chamber to treat the fluid, and first and second intensity sensors that are respectively supported by the first and second light source assemblies and can measure an intensity of UV light incident thereon. The first and second light source assemblies may be arranged so that the first array of LEDs faces the second array of LEDs in the treatment chamber.

[0004] The present disclosure also provides a method of evaluating a condition of at least one of the first and second light source assemblies in the fluid treatment system. The method includes measuring an intensity of UV light in a state in which one of the first and second arrays of LEDs is powered on and the other of the first and second arrays of LEDs is temporarily powered at a different or varying level, and determining whether the intensity of UV light is different from a predetermined value. The intensity of UV light may be measured by at least one of the first and second intensity sensors respectively supported by the first and second light source assemblies.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] FIG. 1 shows a perspective view of a fluid treatment system.

[0006] FIG. 2 is a cross-sectional view of the fluid treatment system.

[0007] FIGS. 3 A and 3B are partial cross-sectional views of a light source assembly detached from the reactor and attached to the reactor, respectively.

[0008] FIG. 4 shows a perspective view of a reactor.

[0009] FIGS. 5A and 5B are perspective views illustrating a light source assembly.

[0010] FIG. 6 is a perspective view illustrating a light source unit.

[0011] FIG. 7 is a perspective view illustrating a light source unit including two intensity sensors.

[0012] FIG. 8 is an exploded perspective view illustrating the light source unit.

DETAILED DESCRIPTION OF EMBODIMENTS

[0013] In the following description, numerous details are set forth to provide an understanding of the present disclosure. However, it may be understood by those skilled in the art that the systems and methods of the present disclosure may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.

[0014] Embodiments of the present disclosure provide a fluid treatment system including a reactor including a treatment chamber for receiving a flow of fluid to be treated, and first and second light source assemblies that respectively include first and second arrays of light-emitting diodes (LEDs) that are configured to emit UV light into the treatment chamber to treat the fluid. The first and second light source assemblies are arranged so that the first array of LEDs faces the second array of LEDs in the treatment chamber. The first and second arrays of LEDs may be arranged to face each other so as to emit the UV light towards each other. For example, the first and second arrays of LEDs may be arranged to face each other along a longitudinal axis of the treatment chamber, or they could be arranged to face each other across a longitudinal axis of the treatment chamber. The system further includes first and second intensity sensors that are respectively supported by the first and second light source assemblies and are configured to measure an intensity of UV light incident thereon. For example, by arranging the first and second intensity sensors at the opposing light source units, the intensity of UV light emitted by each of the opposing light source units can be measured without a separate sensor module.

[0015] Embodiments of the present disclosure also provide a method of evaluating a condition of at least one of the first and second light source units in the fluid treatment system by measuring an intensity of UV light emitted by one of the first and second light source assemblies in a state in which the array of LEDs in the other of the first and second light source assemblies is temporarily powered at a different level, and determining whether the measured intensity is different from a predetermined value. The evaluation can also be performed by modulating the power level to one of the light source units and monitoring the response of the intensity sensor in the other light source. Evaluation can also be performed by modulation of the power level to one of the light source units and monitoring the response of the sensor in the same light source unit.

Fluid Treatment System

[0016] FIG. 1 shows a perspective top view of an exemplary fluid treatment system 100, and FIG. 2 is a cross-sectional view of the fluid treatment system. As shown in FIGS. 1 and 2, the treatment system 100 includes a reactor 102 including a treatment chamber 110 for receiving a flow of fluid for UV radiation treatment. The treatment chamber 110 extends along a longitudinal axis L and includes an inlet 106 through which fluid is introduced into the treatment chamber 110 and an outlet 108 through which the fluid is discharged from the chamber 110 after being treated. The longitudinal axis L may substantially coincide with a longitudinal axis of the reactor 102. The inlet 106 and the outlet 108 are in fluid communication with the treatment chamber 110, and the fluid may flow within the treatment chamber 110 from the inlet 106 to the outlet 108 generally along the longitudinal axis L of the treatment chamber. For example, the inlet 106 and the outlet 108 may be arranged on opposite sides of the treatment chamber 110 along the longitudinal axis L. Alternatively, the inlet or outlet may be arranged perpendicular to the longitudinal axis. [0017] Referring to FIG. 1, the fluid treatment system 100 may further include a controller 150 that is connected to a power source, such as an electrical grid, via the plug 151. As discussed in more detail below, the controller 150 may be configured to control the functioning of the treatment system 100 and/or evaluate a condition of the treatment system 100 and/or components thereof based on measurements received from one or more sensors, including, for example, first and second intensity sensors 126a, 126b, a flow sensor 114, a temperature sensor, and the like.

[0018] In one embodiment, the fluid treatment system 100 may be a residential system for disinfecting water for household use. The system 100 may be installed between a water source, such as a well or municipal water facility, and the household piping. For example, the system 100 may installed at a point of entry of the water into the household piping. The system 100 can be integrated into existing piping for treating the fluid flowing through the piping. For example, the inlet 106 and the outlet 108 may be coupled to the piping for providing in-line flow and a simple connection to the piping without using an L- shape or elbow pipe connector. The system 100 may be installed so as to be integrated with the household piping in the basement of a home at a position where the water flowing from external piping in fluid communication with a well or water treatment facility enters the home. The inlet 106 may receive water flowing from the water source, the treatment chamber may treat the water with UV radiation, making the water safe for use, and the outlet 108 may deliver the treated water to downstream household piping for household use. For residential systems, the treatment chamber 110 can have a volume that is in a range of about 0.25 L to 10 L, from 0.5 L to 5 L, or from 1 L to 3 L, for example. The reactor 102 may be designed for a flow of fluid, such as water or other aqueous fluids (e.g., fluids including at least 75% or at least 90% water), through the treatment chamber 110 at a flow rate in a range of 1 to 25 gallons per minute (gpm), 5 to 20 gpm, or 10 to 15 gpm. Of course, at times, the fluid in the reactor 102 may be substantially stagnant, in which case the flow rate may be less than 1 gpm, less than 0.5 gpm, or less than 0.25 gpm. The treatment system could also be installed just upstream of a “point of use”, such as a faucet or water dispenser.

[0019] The treatment system 100 further includes first and second light source assemblies 120a, 120b that may be removably coupled to the reactor 102. The first and second light source assemblies 120a, 120b respectively include first and second light source units 122a, 122b that are arranged inside the treatment chamber 110 to treat the fluid flowing through the chamber 110 with UV radiation for disinfection, purification, sterilization, or the like. The first and second light source units 122a, 122b are arranged in the treatment chamber 110 so as to be opposed to each other along the longitudinal axis L of the treatment chamber 110. However, the present disclosure is not limited to this arrangement, and the first and second light source units 122a, 122b may be arranged to oppose each other along any suitable direction, including a direction transverse to the longitudinal axis L. The first and second light source units 122a, 122b respectively include first and second arrays of UV LEDs 124a, 124b that are configured to emit UV radiation inside the treatment chamber 110 of the reactor 102. The first and second arrays of LEDs 124a, 124b may emit light in the UV spectrum, for example, in a wavelength band of about 100 nm to about 405 nm, a wavelength band of about 140 to about 330 nm, or a wavelength band of about 180 nm to about 280 nm. The UV light in the above wavelength bands has high germicidal efficacy and may kill at least 99% of microorganisms, such as bacteria, fungi, viruses, mold, and the like, in the fluid, making the fluid safe for use and consumption. The LEDs 124a, 124b may have an efficiency in converting electrical energy to UV light energy in a range of about 3% to about 30%, a range of about 4% to about 15%, or a range of about 5% to about 10%. Ideally the LEDs may have efficiency of 5% or more in converting electrical energy to UV light energy. The reactor may be designed to deliver a UV dose of 5 mJ/cm² to 100 mJ/cm², or about 30mJ7cm², to the fluid at the target flow rate and target water quality, or may be designed to deliver any other suitable UV dose to the fluid.

[0020] The first and second light source assemblies 120a, 120b also respectively include first and second intensity sensors 126a, 126b. The first and second intensity sensors 126a, 126b are designed to measure an intensity of UV light incident thereon. The first and second intensity sensors 126a, 126b may be respectively supported by the first and second light source assemblies 120a, 120b. For example, the intensity sensors 126a, 126b may be respectively arranged in or on the first and second light source assemblies 120a, 120b, such as in or on the first and second light source units 122a, 122b. In an embodiment, the first and second intensity sensors 126a, 126b are respectively arranged in the first and second light source units 122a, 122b along with the first and second arrays of LEDs 124a, 124b. For example, as shown in FIG. 2, the first and second light source units 122a, 122b may respectively include a first housing 130a and a second housing 130b in which the first and second arrays of LEDs 124a, 124b and the first and second intensity sensors 126a, 126b are respectively arranged. The first and second housings 130a, 130b may further respectively include first and second UV transparent windows 132a, 132b that are respectively arranged to cover the first array of LEDs 124a and the first intensity sensor 126a and the second array of LEDs 124b and the second intensity sensor 126b, respectively. By respectively arranging first and second intensity sensors 126a, 126b to be supported by the first and second light source assemblies 120a, 120b, there is no need to provide a separate sensor module including housing, a dedicated window, seals, and electrical components for the sensors 126a, 126b, which can increase cost and reliability issues. The sensors 126a, 126b can be respectively sealed in the first and second light source units 122a, 122b so as to be covered by the first and second windows 132a, 132b covering the first and second arrays of LEDs 124a, 124b. The first and second intensity sensors 126a, 126b are discussed in more detail below.

[0021] In FIG. 2, the "y" direction is parallel to the longitudinal axis L of the reactor 102 and the direction of fluid flow through the treatment chamber 110 between the inlet 106 and the outlet 108. The "x" and "z" directions are radial directions of the reactor 102, where the "z" direction is parallel to an insertion/removal direction of the light source units 122a, 122b into the treatment chamber 110 of the reactor 102.

[0022] The first and second light source assemblies 120a, 120b further include first and second caps 138a, 138b that are arranged outside of the reactor 102 and removably coupled to first and second lateral ports 112a, 112b formed in the outer wall 104 of the reactor 102 to support the light source units 122a, 122b suspended inside the treatment chamber 110.

[0023] As shown in FIG. 2, the first and second light source assemblies 120a, 120b are removably coupled to the reactor 102 via the caps 138a, 138b such that the first and second light source units 122a, 122b are arranged inside the treatment chamber 110 and are oriented for directing UV radiation into the fluid flowing through the treatment chamber 110. In the example shown in FIG. 2, the light source units 122a, 122b are concentric with the chamber 110 and are orthogonal to both the longitudinal axis L of the treatment chamber 110 and the direction of fluid flow (along the Y direction) through the treatment chamber 110 between the inlet 106 and the outlet 108. However, the present disclosure is not limited to this, and the light source units 122a, 122b can be arranged in any suitable orientation for sufficiently treating the fluid flowing through the treatment chamber 110 with UV radiation. The light source units 122a, 122b may be oriented so that a plane of the UV transparent windows 132a, 132b and/or a plane of the backside (z.e., non-emitting side) of the housing 130a, 130b is transverse or orthogonal to the longitudinal axis of the reactor 102 and/or is transverse or orthogonal to a direction of fluid flow through the treatment chamber 110. For example, the plane of the windows 132a, 132b and/or the plane backside of the light source units 122a, 122b may be oriented at any suitable angle transverse to the longitudinal axis L of the treatment chamber 110, such as an angle in a range of 20° to 160°, a range of 30° to 150°, or a range of 45° to 135°. The plane of the windows 132a, 132b and/or the plane backside of the light source unit 122a, 122b may additionally or alternatively be transverse or orthogonal to the direction of fluid flow through the treatment chamber 110 so as to be oriented at an angle with respect to the direction of fluid flow in a range of 20° to 160°, a range of 30° to 150°, or a range of 45° to 135°.

[0024] Similarly, the first and second arrays of LEDs 124a, 124b may be arranged in a plane that is transverse or orthogonal to the longitudinal axis L of the reactor 102 and/or is transverse or orthogonal to a direction of the fluid flow through the treatment chamber 110. The plane of the first and second arrays of LEDs 124a, 124b may be oriented at any suitable angle transverse to the longitudinal axis L of the treatment chamber 110, such as an angle in a range of 20° to 160°, a range of 30° to 150°, or a range of 45° to 135°. The LED arrays 124a, 124b may additionally or alternatively be transverse or orthogonal to the direction of fluid flow through the treatment chamber 110 so as to be oriented at an angle with respect to the direction of fluid flow in a range of 20° to 160°, a range of 30° to 150°, or a range of 45° to 135°.

[0025] The first and second light source assemblies 120a, 120b are arranged so that the first array of LEDs 124a faces the second array of LEDs 124b in the treatment chamber 110. In this context, "faces" may mean that the beams of UV radiation from the first and second arrays of LEDs 124a, 124b at least partially overlap each other. For instance, the light-emitting sides of the light source units 122a, 122b (z.e., the sides through which UV light passes, e.g., on the sides of the UV transparent windows 132a, 132b) may be directly opposed to each other at a normal angle, offset with respect to each other along the longitudinal axis L or other direction, or angled with respect to each other, as discussed in more detail below.

[0026] In the example shown in FIG. 2, the first and second light source assemblies 120a, 120b are arranged so that the main directions of the radiation beams emitted by the first and second arrays of LEDs 124a, 124b are along arrows R_a and Rb towards each other. In particular, the first light source assembly 120a is arranged so that the first array of LEDs 124a emits UV radiation generally in the direction R_a toward the second light source unit 122b, whereas a back side of the first light source unit 122a faces the outlet 108, and the second light source assembly 120b is arranged so that the second array of LEDs 124b of the second light source unit 122b emits UV radiation generally in the direction Rb toward the first light source unit 122a, whereas a backside of the second light source unit 122b faces the inlet 106. In FIG. 2, the UV LED arrays 124a, 124b are each arranged in a plane orthogonal to the longitudinal axis L and the LED arrays 124a, 124b are directly opposed to each other along the longitudinal axis L so that the main directions R_a and Rb of the beams of radiation are generally parallel to and/or coincident with the longitudinal axis L. However, the present disclosure is not limited to this arrangement, and the first and second light source assemblies 120a, 120b may be arranged in any suitable manner so that the beams of radiation from the first and second arrays of LEDs 124a, 124b at least partially overlap each other.

[0027] For example, in another embodiment, the light-emitting sides of the light source units 122a, 122b may face each other (e.g., be directly opposed) along a direction transverse to the longitudinal axis L, such as a direction at an angle in a range of 20 to 160°, a range of 30° to 150°, or a range of 45° to 135° from the longitudinal axis L. In this case, a direction extending between the light-emitting sides of the first and second light source units 122a, 122b and normal to the planes of the first and second LED arrays 124a, 124b is transverse to the longitudinal axis L, such as at an angle in one of the above ranges.

[0028] Alternatively or additionally, the first and second light source assemblies 120a, 120b may be arranged so that the light-emitting sides directly face (e.g., oppose) each other but the light source units 122a, 122b are offset from each other. For example, one or both of the light source units 122a, 122b may be offset from the longitudinal axis or each other in a radial or width direction of the reactor 102 (e.g., in a direction transverse to the longitudinal axis L) so that the beams of UV radiation emitted from the light source units 122a, 122b only partially overlap. In such an arrangement, a center of the first LED array 124a may not be aligned with a center of the second LED array 124a, and the center of one or both of the LED arrays 124a, 124b may be offset from the longitudinal axis and/or offset from each other.

[0029] In the above embodiments, the first and second light source assemblies 120a, 120b may be arranged so that the planes of the first and second LED arrays 124a, 124b are generally parallel to each other. However, the present disclosure is not limited to this arrangement, and the first and second light source assemblies 120a, 120b may be arranged so that the planes of the LED arrays 124a, 124b are angled with respect to each other. For example, the planes of the LED arrays 124a, 124b may be angled with respect to each other, for example, at an angle in a range of 5 to 175°, a range of 20° to 150°, or a range of 45° to 135°, or any other suitable angle at which the beams of UV radiation at least partially overlap.

[0030] By arranging the first and second light source assemblies 120a, 120b so that the first and second arrays of LEDs 124a, 124b face each other (e.g., such that the beams of UV radiation at least partially overlap each other), the time that the fluid is exposed to the UV radiation can be extended. This can ensure that the fluid flowing through the treatment chamber is sufficiently irradiated with UV radiation for disinfecting the fluid to make it safe for use and consumption. For example, by arranging the first and second light source assemblies 120a, 120b so that the first and second arrays of LEDs 124a, 124b face each other, and emit UV radiation in the main directions R_a, Rb towards each other generally along the longitudinal axis L of the treatment chamber 110 and/or the direction of fluid flow, the fluid flowing through the chamber 110 can be irradiated with UV light along substantially the entire length of the chamber 110 or along substantially most of or a majority of the length of the chamber 110. Additionally, by arranging the first and second light source assemblies 120a, 120b so that the first and second arrays of LEDs 124a, 124b face each other (e.g., such that the beams of UV radiation at least partially overlap each other), the first and second intensity sensors 126a, 126b respectively comprised by the first and second light source assemblies 120a, 120b, can measure an intensity of UV light emitted by the opposing light source unit.

[0031] Continuing to refer to FIG. 2, the light source units 122a, 122b are arranged in the treatment chamber 110 so as to be in contact with the fluid flowing through the treatment chamber 110 for UV treatment. For example, the light source units 122a, 122b may be arranged so as to be partially or fully immersed in the fluid flowing through the treatment chamber 110. In other words, the fluid flowing through the treatment chamber 110 impinges on and flows around the light source units 122a, 122b. The fluid may not only impinge on and flow around the front, light-emitting side of the light source units 122a, 122b, but may also impinge on and flow around the back side of the light source units 122a, 122b, where considerable heat is often generated. Thus, the fluid being treated can be used to continuously cool the light source units 122a, 122b.

[0032] Although FIGs. 1 and 2 show an exemplary fluid treatment system 100 including two light source assemblies 120a, 120b, the present disclosure is not limited to any particular number of light source assemblies so long as the number of light source assemblies is sufficient to disinfect the fluid. The number of light source assemblies 120 may be determined based on the flow rate and/or level of disinfection. For example, the treatment system 100 may include any suitable number of light source assemblies for disinfecting the fluid, such as at least one, at least two, at least three, or at least four light source assemblies, and up to twenty light source assemblies, up to ten light source assemblies, or up to five light source assemblies. [0033] Relatedly, although FIGs. 1 and 2 show an exemplary fluid treatment system 100 in which the light source assemblies 120a, 120b are laterally or radially insertable into and removable from the treatment chamber 110, the present disclosure is not limited to this arrangement. The light source assemblies 120a, 120b may be arranged in any suitable manner for emitting UV radiation to the fluid flow through the treatment chamber 110. For example, the light source assemblies 120a, 120b may be axially insertable into and removable from the treatment chamber 110, for example, through axial ends of the treatment chamber 110. For instance, the light source assemblies 120a, 120b may be built into the axial ends of the treatment chamber 110 or reactor vessel 102 instead of being radially insertable and removable through the ports 112a, 112b. In this case, the inlet 106 and outlet 108 may be oriented radially instead of axially as shown in FIGs. 1 and 2. In such an arrangement, the light source assemblies 120a, 120b may face (e.g., emit UV light) generally towards each other along the longitudinal axis L, and the fluid flowing through the treatment chamber 110 may contact (e.g., impinge on) the windows 132a, 132b of the light source assemblies 120a, 120b, but the fluid may not contact the back side of the light source assemblies 120a, 120b or flow around the sides of the light source assemblies 120a, 120b. Alternatively, the light source assemblies 120a, 120b may be arranged in a lateral wall of the treatment chamber 110 so as to face each other (e.g., emit UV light generally towards each other) generally along a radial direction of the treatment chamber 110 orthogonal to the longitudinal axis L.

[0034] Additionally, although FIGs. 1 and 2 show an exemplary fluid treatment system 100 in which the first and second intensity sensors 126a, 126b are provided in respective (z.e., different) light source assemblies 120a, 120b, the present disclosure is not limited to this. As discussed below with respect to FIG. 7, the first and second intensity sensors 126a, 126b may be provided in the same light source assembly 120. In this case, the first and second intensity sensors 126a, 126b may be oriented differently from each other so as to face in different directions and/or the intensity sensors 126a, 126b may include different optical systems (e.g., input optics) 127.

[0035] The fluid treatment system 100 may further include a flow sensor 114 for measuring a flow rate of the fluid flowing through the treatment chamber 110. As shown in FIGs. 1 and 2, the flow sensor 114 may be integrated in the outlet 108. Alternatively, the flow sensor 114 may be integrated in the inlet 106 or inside the treatment chamber 110. With reference to FIG. 1, the controller 150 may control the flow sensor 114 to measure the flow rate of fluid flowing through the treatment chamber 110 and the flow sensor 114 may transmit the measured flow rate to the controller 150. The controller 150 may be configured to use the measured flow rate to modulate UV LED power proportional to flow. For example, when there is low flow or no flow, the controller 150 may be configured to turn off or reduce power to the UV LEDs 124 to a low, idle power. This may include, for example, switching to pulse width modulation at the idle power.

[0036] FIGs. 3 A and 3B show an example of removably coupling a light source assembly 120 to a reactor 102. FIG. 3A shows an open state in which the light source assembly 120 is not coupled to the reactor 102, and FIG. 3B shows a closed state in which the light source assembly 120 is coupled to the reactor 102. In FIG. 3A, the light source assembly 120 is in a state of being coupled to or removed from the reactor 102. As shown in FIG. 3A, the light source assembly 120 can be removably coupled to the reactor 102 by inserting the light source unit 122 into the treatment chamber 110 through an opening in the port 112 of the reactor 102 in a direction (e.g., the Z direction) transverse to the longitudinal axis L, and coupling the cap 138 to the port 112 of the reactor 102. Likewise, the light source assembly 120 can be uncoupled from the reactor 102 by uncoupling the cap 138 from the port 112 and removing the light source unit 122 from the treatment chamber 110 of the reactor 102 in a direction (e.g., the Z direction) transverse to the longitudinal axis L. As shown in FIG. 3B, the cap 138 is coupled to the lateral port 112 of the reactor 102 to removably couple the light source assembly 120 to reactor 102.

[0037] In FIGs. 3A and 3B, the light source unit 122 is inserted into and removed from the treatment chamber 110 along the Z direction, which is orthogonal (e.g., at an angle of about 90°) to the longitudinal axis L of the treatment chamber 110. However, the present disclosure is not limited to this arrangement, and the light source unit 122 may be inserted into and removed from the treatment chamber 110 by movement along a direction at any suitable angle transverse to the longitudinal axis L of the treatment chamber 110, such as an angle in a range of 20° to 160°, a range of 30° to 150°, or a range of 45° to 135°.

[0038] During use, the light source unit 122 of the light source assembly 120 may periodically become fouled with foreign materials, which can block or reduce transmission of the UV radiation to the fluid. Once fouling has reached a certain point, the light source assembly 120 may be cleaned to remove the fouling materials and optimize the system. By arranging the light source assembly 120 to be insertable and removable along a direction transverse to the longitudinal axis L of the treatment chamber 110, the light source assembly 120 can be easily removed from the reactor 102 without disturbing the piping connection for cleaning to remove fouling materials from the light source unit 122, as well as for other routine maintenance or servicing. This is particularly advantageous when the system is installed in existing household piping, where there is limited space.

[0039] Referring to FIG. 4, the reactor 102 may be a vessel having a substantially cylindrical body defined by an outer wall 104. For example, the reactor 102 may have a circular cross-sectional shape, as shown in FIG. 4. However, the present disclosure is not limited to any particular cross-sectional shape, and the reactor 102 may have various other cross-sectional shapes, for example, an elliptical shape, a polygonal shape including, for example, a square or rectangular shape, and a semicircular shape. For residential systems, the reactor 102 may have a length, in a direction along the longitudinal axis L from the inlet 106 to the outlet 108, in a range of 100 mm to 1,000 mm, 200 mm to 500 mm, or 240 mm to 350 mm. The treatment chamber 110 of the reactor 102 may have a diameter or width dimension in a direction orthogonal to the longitudinal axis L in a range of 25 mm to 250 mm, 50 mm to 200 mm, or 75 mm to 150 mm.

[0040] As discussed above, the reactor 102 may include first and second lateral ports 112a, 112b including openings formed in the outer wall 104 for receiving the first and second light source assemblies 120a, 120b. However, the present disclosure is not limited this, and may have any number of ports corresponding to the number of light source assemblies. For example, the reactor 102 may include at least one, at least two, at least three, or at least four ports 112, and up to twenty, up to ten, or up to five ports 112. Alternatively, the reactor 102 may not include any ports, for example, in a case where the light source assembl(ies) are axially inserted into the treatment chamber 110 or are otherwise provided in the system 100. The ports 112a, 112b may include an external thread 113a, 113b designed to threadedly engage internal threads 137 (shown in FIG. 5B) of the cap 138 of the light source assembly 120. Alternatively, the ports 112a, 112b may include any other connecting mechanism suitable for detachably connecting to the light source assemblies 120a, 120b. The ports are shown on a lateral or radial surface of the reactor, but could also be arranged on an axial surface, such that the light source assembly inserts axially into the reactor.

[0041] Further details of the light source units 122a, 122b will be discussed with reference to FIGS. 5A-8. FIGs. 5A and 5B show perspective views of an exemplary light source assembly 120, FIG. 6 shows a perspective view of an exemplary light source unit 122 including an array of a plurality of UV LEDs 124, FIG. 7 shows a perspective view of an exemplary light source unit 122 including a plurality of UV LEDs 124 and two intensity sensors 126a, 126b, and FIG. 8 shows an exploded view of the light source unit 122. Each light source unit 122 of the assembly 120 may have a disc shape. For example, the light source unit may have a shape resembling a puck. However, the present disclosure is not limited to any particular shape, and each the light source unit 122 may have any suitable shape, including but not limited to cylindrical, conical, frustoconical, cubical, rectangular, or the like. For example, each light source unit 122 may have a circular cross-sectional shape, as shown in FIG. 5A, 5B, and 6. However, the present disclosure is not limited to any particular cross-sectional shape, and the light source unit 122 may have various other cross- sectional shapes, for example, an elliptical shape, a polygonal shape including, for example, a square or rectangular shape, and a semicircular shape. Regardless of shape, the light source units 122a, 122b can be sized relative to the treatment chamber 110 to allow for sufficient fluid flow within the reactor 102 so that the treatment of the fluid is efficient. In this regard, a cross-sectional area of one of the light source units 122a, taken on a plane orthogonal to the longitudinal axis L, can be from 25%-60% of the cross-sectional area of the treatment chamber 110, or from 35%-45% of the cross-sectional area of the treatment chamber 110. If the light source inserts axially, the cross sectional area could be 100% of the area of the treatment chamber.

[0042] The light source unit 122 may include a thickness dimension that is oriented in the treatment chamber 110 along the longitudinal axis L of the treatment chamber 110 and a width dimension that is oriented in the treatment chamber 110 orthogonally to the longitudinal axis L of the treatment chamber 110. A maximum width dimension of the light source unit 122 may be at least twice that of a maximum thickness dimension of the light source unit 122. The maximum width dimension of the light source unit 122 may be 2 to 20 times larger than the maximum thickness dimension, 3 to 15 times larger than the maximum thickness dimension, or 5 to 10 times larger than the maximum thickness dimension of the light source unit 122. For example, in a case where the light source unit 122 is cylindrical and has a circular cross-sectional shape, the width dimension may correspond to a diameter of the light source unit 122, and the thickness dimension may correspond to a length of the cylindrical light source unit 122 that is oriented in the treatment chamber 110 along the longitudinal axis of the treatment chamber 110 and is orthogonal to the diameter of the light source unit 122.

[0043] As mentioned above, the light source unit 122 includes a housing 130 in which the array of UV LEDs 124 is arranged. The housing 130 may be made at least partially of a heat-conductive material, such as stainless steel, aluminum, copper, or alloys thereof, to facilitate heat dissipation from the light source unit 122 to the fluid being treated in the chamber 110. For example, at least a backside of the housing 130, which is opposite to the light-emitting side, may be made of a heat-conductive material to facilitate dissipation of the heat away from the light source unit 122, e.g., into the fluid being treated.

[0044] The housing 130 may define the shape of the light source unit 122. For example, the housing 130 may have a disc shape, such as a shape resembling a puck. However, the present disclosure is not limited to any particular shape, and the housing 130 may have any suitable shape, including but not limited to cylindrical, conical, frustoconical, cubical, rectangular, or the like. For example, the housing 130 may have a circular cross- sectional shape, as shown in FIG. 5A, 5B, and 6. However, the present disclosure is not limited to any particular cross-sectional shape, and the housing 130 may have various other cross-sectional shapes, for example, an elliptical shape, a polygonal shape including, for example, a square or rectangular shape, and a semicircular shape.

[0045] The housing 130 may include a thickness dimension that is oriented in the treatment chamber 110 along the longitudinal axis L of the treatment chamber 110 and a width dimension that is oriented in the treatment chamber 110 orthogonally to the longitudinal axis L of the treatment chamber 110. A maximum width dimension of the housing 130 may be at least twice that of a maximum thickness dimension of the housing 130. The maximum width dimension of the housing 130 may be 2 to 20 times larger than the maximum thickness dimension, 3 to 15 times larger than the maximum thickness dimension, or 5 to 10 times larger than the maximum thickness dimension of the housing 30. For example, in a case where the housing 130 is cylindrical and has a circular cross-sectional shape, the width dimension may correspond to a diameter of the housing 130, and the thickness dimension may correspond to a length of the cylindrical housing 130 that is oriented in the treatment chamber 110 along the longitudinal axis L of the treatment chamber 110 and is orthogonal to the diameter of the housing 130.

[0046] A UV transparent window 132 may be arranged on the other side (z.e., the light-emitting side) of the housing 130 so as to cover the UV LEDs 124. The UV LEDs 124 are arranged to emit UV radiation through the UV transparent window 132. The window 132 may be made of any material that is suitably transparent to UV radiation, such as quartz or silica glass, or could be made of a fluoropolymer. The UV transparent window 132 may be machined and have a substantially flat surface. A plane of the UV transparent window 132 may be parallel to the width dimension of the light source unit 122 and the housing 130. The window may be sealed to prevent fluid from entering the lights source unit 122. For example, as shown in FIG. 8, the window 132 may be secured to the housing by a ring 131 or other sealing material. The ring 131 may threadedly engage external threads on the housing 130 to secure the window 132 against the housing or the array of UV LEDs 124 arranged in the housing 130. Alternatively, the ring 131 may couple to the housing 130 by any other suitable connection mechanism. One or more O-rings 134, 135 may be used to seal the window 132 against the body of the housing 130 and to secure the opposite side of the window 132 in place over the UV LEDs 124 inside the housing 130. For example, one or more of the O- rings 134, 135 may be made of polytetrafluoroethylene (PTFE). One or both of the O-rings 134, 135 may provide a cushion to protect the window 132 from damage due to pressure in the treatment chamber 110.

[0047] The UV LEDs 124 are mounted on and electrically coupled to a circuit board 128, such as a printed circuit board (PCB) or a metal core printed circuit board (MCPCB), which is also arranged in the housing 130 on an opposite side of the window 132. The circuit board 128 may be inset inside the housing 130. A plane of the circuit board 128 may be oriented parallel to the width dimension of the light source unit 122 and the housing 130. The UV LEDs 124 may be arranged in any suitable pattern on the circuit board 128. The number of UV LEDs 124 arranged in the light source unit 122 may be determined based on the flow rate and/or level of disinfection. In one example, the light source unit 122 may include a number of UV LEDs 124 in a range of 5 to 100, a range of 15 to 50, or a range of 10 to 30.

[0048] The circuit board 128 may include a metal backing or metal core made of a heat-conductive material, such as copper, aluminum, and alloys thereof, in order to facilitate conducting heat away from the light source unit 122. For example, the heat generated by the light source unit 122 can be dissipated to the fluid being treated into the treatment chamber 110 through the heat-conductive backing or core and the heat-conductive housing 130. The heating-conductive backing on the circuit board 128 may be in direct contact with the thermally-conductive back of the housing 130 to facilitate heat dissipation to the fluid. The circuit board may incorporate metal-filled “vias” to conduct heat from the LEDs to the opposite face of the circuit board. A thermally conductive material, such as a gel, paste, or film, may be used between the circuit board and the housing to facilitate heat transfer away from the circuit board and LEDs.

[0049] The light source unit 122 may be arranged in the treatment chamber 110 such that the UV transparent window 132, the array of LEDs 124, the circuit board 128, and the backside (non-emitted side) of the housing 130 are stacked in this order along a direction of the thickness dimension of the light source unit 122, which extends along the longitudinal axis L of the treatment chamber 110. [0050] The treatment chamber 110 and/or the light source unit 122 may optionally include a UV reflector for facilitating irradiation of the UV light into the fluid flowing through the chamber 110. For example, the UV reflector may be made of any suitably reflective material, such as polytetrafluoroethylene (PTFE), aluminum, stainless steel, or the like. The UV reflector may be provided as a coating applied on an inner surface of the treatment chamber 110, or may be a polished inner surface of the chamber 110, for example, where the chamber wall is made of a reflective material. Alternatively or additionally, a UV reflector may be provided in the light source unit 122, for example, as a parabolic reflector or a reflective coating or material, for example, provided on the circuit board 128.

[0051] As mentioned above, each light source unit 122 may include a respective intensity sensor 126. The intensity sensor 126 may be mounted on the circuit board 128 in the respective light source unit 122 and electrically coupled thereto, or the sensor 126 may be otherwise provided in the light source unit 122. For example, the intensity sensor 126 may be provided in the light source unit 122, for example, inside the housing 130, and may include its own circuit board or other circuitry separate from the circuit board 128 on which the UV LEDs 124 are mounted. For example, as shown in FIG. 5A, each light source unit 122 may include a UV light intensity sensor 126 arranged in the center of the light source unit 122, such as a center of the circuit board 128, as shown in FIG. 5 A or any other suitable location in the light source unit 122. The intensity sensor 126 may be, for example, an intensity sensor chip, a photodiode, a photodetector, photoresistor, a UV phototube, UV photomultiplier tube, or any other suitable sensor for measuring the intensity of UV light. A suitable photodiode may be composed of Silicon Carbide, which has high sensitivity and durability to UV but is “blind” to visible light and has low dark current. As discussed in more detail below, the intensity sensor 126 is designed to measure an intensity of UV light incident thereon. For example, the intensity sensor 126 may measure an intensity of UV light emitted by an opposing light source unit or it may measure an intensity of UV light emitted by the light source unit in which it is arranged (the self source unit) through lateral emission or back reflected light from the window 132 or a component of the reactor.

[0052] Alternatively, as shown in FIG. 7, the first and second intensity sensors 126a, 126b may be provided in the same light source assembly 120. In this case, the first and second intensity sensors 126a, 126b may be oriented differently from each other so as to face in different directions and/or the intensity sensors 126a, 126b may include different optical systems (e.g., input optics) 127. [0053] With respect to the different orientations, the intensity sensors 126a, 126b may be oriented differently from each other so as to face in different directions (e.g., directions at an angle with respect to each other). For example, a direction normal (z.e., orthogonal) to a light receiving surface of the first intensity sensor 126a may be different from (e.g., angled with respect to) a direction normal to a light receiving surface of the second intensity sensor 126b. The two normal directions may be angled with respect to each by any suitable angle greater than 0° and less than 180°, for example, an angle in a range of 10° to 170°, a range of 30° to 150°, or a range of 60° to 120°, or any other suitable angle.

[0054] Alternatively or additionally, the first and second intensity sensors 126a, 126b may include different optical systems or input optics 127. The different input optics 127 may include: a lens, a mirror or reflective surface, an aperture, a hollow tube, a diffuser, a transparent rod (light pipe), such as a quartz rod, or any combination of one or more of these elements. In FIG. 7, the first and second intensity sensors 126a, 126b are both oriented in the same direction so as to face generally along an axial direction of the housing 130. That is, the light-receiving surfaces (i.e., the surfaces facing/on the side of the window 132) of the first and second intensity sensors 126a, 126b are parallel or coincident to each other in FIG. 7 so that the directions normal to the light-receiving surfaces of the sensors 126a, 126b are parallel and not angled with respect to each other. However, the second intensity sensor 126b further includes a different input optic 127 (e.g., tube, quartz rod, lens, etc.).

[0055] Due to the different input optic 127 in FIG. 7, the light reaching the first and second intensity sensors 126a, 126b may travel through different layers of fluid, different reflection, different fouling of the window 132, and the like, which will affect the intensities reaching the first and second sensors 126a, 126b. Similarly, if the first and second intensity sensors 126a, 126b were oriented differently so as to face (e.g., receive light) in generally different directions (e.g., directions at an angle with respect to each other), the light intensities reaching the first and second intensity sensors 126a, 126b would similarly differ from each other due to, for example, traveling through different layers of fluid, different reflection, different fouling of the window 132, and the like. As a result, the two intensity sensors 126a, 126b within the same light source assembly 120 will respond differently to the UV radiation field in the disinfection reactor 102, providing different signals.

[0056] As discussed in more detail below, the two signals from the first and second intensity sensors 126a, 126b can be compared, which can make it possible to determine properties of the fluid flowing through the treatment chamber 110, the reactor 102, and/or the source assembly 120. For example, by comparing the signals from the first and second sensors 126a, 126b, various properties may be determined, such as: UV optical absorbance (“UVT”) of the fluid in contact with the source assembly 120, the reflectivity of a surface of the reactor 102, the amount of optical attenuation (fouling) on the window 132, the output of the LEDs 124, the output of another light source assembly in the reactor 102.

[0057] The light source unit 122 according to any of the embodiments described above may further include any other suitable sensor in addition to the intensity sensor 126. For instance, the light source unit 122 may include a temperature sensor for monitoring the temperature of the light source unit 122. The temperature sensor may be mounted on the circuit board 128, or otherwise provided in the light source unit 122. The temperature sensor may be provided in a center of the light source unit 122, where the light source unit 122 may get hottest during use. The temperature sensor may be a thermistor or a thermocouple any other sensor suitable for sensing a temperature in the light source unit 122.

[0058] The temperature sensor may be used to determine whether fluid is flowing through the chamber 110. For example, when the fluid flows through the chamber 110, the light source unit 122 may be cooled by the flowing fluid, and thus, there may be a corresponding decrease in the temperature of the light source unit 122 upon fluid flow through the chamber 110. The temperature sensor may be used to monitor the condition of the flow sensor 114. For example, if the temperature sensor measures a change in temperature indicative of fluid flow, but the flow sensor 114 has not detected flow, this may indicate that the flow sensor 114 is not working properly. In such a case, the flow rate may be determined from the temperature change of the lights source unit 122 and the temperature of the water, and the determined flow rate may be temporarily used for modulating power to the UV LEDs 124 instead of shutting down the system.

[0059] The circuit board 128 may further include a connector 142, such as a multipin connector for electrically connecting the circuit board 128 to a power source. For example, the connector may be connected to one end of a ribbon cable 140 (shown in FIG. 5B). As discussed in more detail below, the ribbon cable 140 extends outside of the light source unit 122. For example, the other end of the ribbon cable 140 may be connected to a circuit board 148 arranged in the cap 138.

[0060] As mentioned above, the light source assembly 120 also includes a cap 138 for coupling the assembly to the reactor 102. The light source unit 122 is mounted on a mounting arm 146 that extends from the cap 138. The ribbon cable 140 may be arranged to extend from the connector 142 through an inner channel of the mounting arm 146 to inside of the cap 138, where it is coupled to a connector 144 provided on the circuit board 148. The circuit board 148 inside the cap 138 may be coupled to a power source. For example, referring to FIG. 8, the circuit board 128 in each of the light source assemblies 120a, 120b is electrically coupled to a power source via cables 121a, 121b.

[0061] The cap 138 further includes internal threads 137 for coupling to a lateral port 112 of the reactor 102. For example, the internal threads 137 of the cap 138 may be designed to threadedly engage external threads 113 provided on the lateral port 112 of the reactor 102. However, the present disclosure is not limited to a threaded connection, and any other suitable connection mechanism may be used.

Control of the System and Methods for Evaluating the Li ht Source Assemblies [0062] As mentioned above, the system 100 may include at least two intensity sensors 126a, 126b. In an embodiment, the first and second light source assemblies 120a, 120b may respectively include first and second intensity sensors 126a, 126b. The first and second intensity sensors 126a, 126b may measure an intensity of UV light incident thereon. By arranging the light source assemblies 120a, 120b in the manner discussed above (e.g., so that the UV arrays 124a, 124b face each other so that the UV radiation beams at least partially overlap), the first and second intensity sensors 126a, 126b may measure an intensity of UV light emitted by the opposing light source unit 122a, 122b and/or the sensors 126a, 126b may measure an intensity of UV light emitted by the light source unit 122a, 122b in which it is arranged (the self source unit) through lateral emission or back reflected light from the window 132a, 132b of the light source unit 122a, 122b or from the reactor 104 or a surface of the opposite source unit.

[0063] In another embodiment, the first and second intensity sensors 126a, 126b may be provided in one (z.e., the same) light source assembly 120 so as to be oriented in different directions (z.e., directions normal to the light-receiving surfaces of the first and second intensity sensors 126a, 126b may be different) and/or may include different input optics 127, such as a lens, a mirror or reflective surface, an aperture, a hollow tube, a diffuser, a transparent rod (light pipe), or any combination thereof.

[0064] By the presence of at least two intensity sensors 126a, 126b — either in different light source assemblies or in the same light source assembly — properties and/or the health or a condition of various components of the treatment system 100, as well as the fluid flowing through the reactor 102 and treatment chamber 100, may be determined (e.g., evaluated) and/or monitored. For example, the intensity measurements by the intensity sensors 126a, 126b may be used to evaluate and monitor the health or a condition of the first and second light source assemblies 120a, 120b and/or the first and second arrays of LEDs 124a, 124b. LEDs degrade over time, and as time passes, the intensity of UV light emitted by the LEDs may decrease. Additionally, during use, the parts of the light source assemblies 120a, 120b that are exposed to the fluid, including, for example, the light source units 122a, 122b, and parts thereof, including, for example, the windows 132a, 132b may periodically become fouled with foreign materials, which can partially or completely block transmission of the UV radiation into the fluid. Once fouling has reached a certain point, the light source assemblies 120a, 120b may be cleaned to remove the fouling materials and optimize the system. Monitoring the intensity of light emitted by the arrays of LEDs 124a, 124b can help determine whether the light source assemblies 120a, 120b are malfunctioning, including evaluating how the LEDs are aging, including, for example, determining whether the LEDs are prematurely aging such that the LEDs are degrading faster than expected; determining whether there is an internal problem, such as an electrical or other problem causing a decrease in intensity of the UV light; and/or determining whether the light source assemblies 120a, 120b are fouled with foreign materials that are blocking transmission of the UV light into the fluid in the treatment chamber 110.

[0065] The controller 150 may be configured to evaluate the condition of the first and second light source assemblies 120a, 120b based on the measured intensity values. For example, the controller 150 may be configured to control the treatment system 100 to perform a method for evaluating the condition of the first and second light source assemblies 120a, 120b. During such evaluation, the controller 150 may be configured to temporarily stop or modulate (e.g., decrease) a supply of power to one of the first and second arrays of LEDs 124a, 124b in the respective one of the first and second light source units 122a, 122b of the respective light source assemblies 120a, 120b so that the intensity of UV light emitted by the other of the first and second light source units 122a, 122b can be measured. Although the power to the one array of LEDs is temporarily stopped or modulated, one or both of the first and second intensity sensors 126a, 126b may be kept active to measure the intensity of UV light incident thereon. The controller 150 is configured to receive a signal corresponding to the measured intensity of the UV light from at least one of the first and second intensity sensors 126a, 126b in the state in which the one array of LEDs is powered on and the other array of LEDs is temporarily modulated (e.g., to a lower power level including being powered off). The first and second intensity sensors 126a, 126b may transmit signals corresponding to the measured intensity values to the controller 150 by any suitable transmission means, including wired and wireless means. [0066] The controller 150 may be further configured to determine whether the measured intensity is different from a predetermined value. For example, when the measured intensity is below the predetermined value, it may indicate that the measured intensity of the UV light emitted by the one array of LEDs 124 that was powered on at the time of measurement is lower than desired or expected or the measured intensity is close to, approaching, or at or below a minimum intensity value for adequately disinfecting the fluid flowing through the chamber. For example, the predetermined value may be an intensity value close to or approaching a minimum intensity value for adequately disinfecting the fluid flowing through the chamber 110. For example, the predetermined value may be within a range of 1% to 25%, 5% to 20%, or 10% to 15% of a minimum intensity value. The minimum intensity value for adequately disinfecting the fluid may vary depending on various factors, including, for example, the size of the treatment chamber 110, the number of light source assemblies 120, the volume of fluid flowing through the chamber 110, and/or the like. Alternatively, the predetermined value may be a minimum desired intensity value that may be well above the minimum intensity value for adequately disinfecting the fluid. The predetermined value may be a minimum expected intensity value based on the age and/or condition of the LED arrays 124a, 124b. The predetermined value may be the same or different for the different LED arrays 124a, 124b and/or the different light source assemblies 120a, 120b. The predetermined value may stay the same or may change over time, for example, based on expected changes in intensity during the lifespan of the LED arrays 124a, 124b.

[0067] If the measured intensity is less than the predetermined value, the controller 150 may be configured to output a notification, for example, in the form of a sound, light, or other error message. The notification may indicate that the one light source assembly 120 is malfunctioning. Malfunctioning of the light source assemblies 120a, 120b may include decreased or no UV light being emitted by the LED arrays 124a, 124b or being transmitted to the fluid in the treatment chamber 110 due to, for example, an internal or other problem, such as LED failure, short circuit, overheating of the LEDs 124a, 124b, or electrical supply overload; a defective light source assembly or LED array; premature or normal aging of the LEDs 124a, 124b such that the LEDs 124a, 124b are degrading, possibly faster than expected; fouling of the light source assemblies 120a, 120b with foreign materials that block transmission of the UV light into the fluid flowing through the treatment chamber 110; or any other problem or issue that may cause decreased UV light emission or transmission to the fluid in the treatment chamber 110. When the controller 150 outputs such a notification, it may indicate, instruct, or suggest that the one light source assembly 120 may need or benefit from servicing or maintenance, for example, to fix a problem, such as an electrical or other problem with the one light source assembly 120, it may indicate that the one light source assembly 120 and/or the LEDs 124 should be replaced, or it may be indicate that the one light source assembly 120 may need or benefit from being cleaned to remove fouling materials that have accumulated on the one light source assembly 120, for example, on the window 132 of the one light source unit 122.

[0068] The controller 150 may periodically evaluate to the condition of the first and second light source assemblies 120a, 120b, or may perform such evaluation upon a trigger, such as a system trigger or input from a person operating the system. The controller 150 may sequentially or non-sequentially evaluate the intensity of light emitted by the first and second arrays of LEDs 124a, 124b in any suitable order.

[0069] For example, the controller 150 may be configured to temporarily stop or modulate a supply of power to the second array of LEDs 124b in the second light source assembly 120b for evaluating a condition of the first light source assembly 120a. In this case, the controller 150 is configured to receive a signal corresponding to a measured intensity of the UV light from at least one of the first intensity sensor 126a and the second intensity sensor 126b in a first state in which the first array of LEDs 124a is powered on and the second array of LEDs 124b is temporarily powered at a different or varying level (including powered off), and determine whether the measured intensity of the UV light in the first state is different from (e.g., less than) a predetermined value. Even though power supplied to the second array of LEDs 124b may be temporarily stopped or modulated, the second intensity sensor 126b is kept active. Therefore, the intensity of the UV light emitted in the first state may be measured by the second intensity sensor 126b in the second light source unit 122b, which faces the first light source unit 122a, or the intensity of UV light may be measured in the first state by the first intensity sensor 126a in the first light source unit 122a through lateral emission from the first array of LEDs 124a or back reflected light from the first window 132a of the first light source unit 122a. Alternatively, the intensity of the UV light emitted in the first state may be measured by both the first intensity sensor 126a and the second intensity sensor 126b. If the measured intensity of UV light in the first state is less than the predetermined value, then controller 150 may be configured to output a notification. For example, the notification may indicate that the first light source assembly 120a is malfunctioning, as discussed above. [0070] After or before evaluating the first light source unit 122a, the controller 150 may be configured to temporarily stop or modulate a supply of power to the first array of LEDs 124a in the first light source assembly 120a for evaluating a condition of the second light source assembly 120b. In this case, the controller 150 is configured to receive a measured intensity of the UV light from at least one of the first intensity sensor 126a and the second intensity sensor 126b in a second state in which the second array of LEDs 124b is powered on and the first array of LEDs 124a is temporarily powered at a different or varying level, and determine whether the measured intensity of the UV light is less than a predetermined value. Even though power supplied to the first array of LEDs 124a may be temporarily stopped or modulated, the first intensity sensor 126a is kept active. Therefore, the intensity of the UV light emitted in the second state may be measured by the first intensity sensor 126a in the first light source unit 122a, which faces the second light source unit 122b, or the intensity of UV light emitted in the second state may be measured by the second intensity sensor 126b in the second light source unit 122b through lateral emission from the second array of LEDs 124b or back reflected light from the second window 132b of the second light source unit 122b. Alternatively, the intensity of the UV light emitted in the second state may be measured by both the first intensity sensor 126a and the second intensity sensor 126b. If the measured intensity of UV light in the second state is less than the predetermined value, then controller 150 may be configured to output a notification. For example, the notification may indicate that the second light source assembly 120b is malfunctioning, as discussed above.

[0071] The controller 150 includes hardware, such as a circuit for processing digital signals and a circuit for processing analog signals, for example. The controller may include one or a plurality of circuit devices (e.g., an IC) or one or a plurality of circuit elements (e.g., a resistor, a capacitor) on a circuit board, for example. The controller 150 may be a central processing unit (CPU) or any other suitable processor. The controller 150 may be or form part of a specialized or general purpose computer or processing system. One or more controllers, processors, or processing units, memory, and a bus that operatively couples various components, including the memory to the controller, may be used. The controller 150 may include a module that performs the methods described herein. The module may be programmed into the integrated circuits of the processor, or loaded from memory, storage device, or network or combinations thereof. For example, the controller 150 may execute operating and other system instructions, along with software algorithms, machine learning algorithms, computer-executable instructions, and processing functions of the fluid treatment system.

[0072] The controller 150 may be operational with numerous other general purpose or special purpose computing system environments or configurations. Examples of well- known computing systems, environments, and/or configurations that may be suitable for use with the disclosed embodiments may include, but are not limited to, personal computer systems, server computer systems, thin clients, thick clients, handheld devices, such as tablets and mobile devices, laptop devices, multiprocessor systems, microprocessor-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputer systems, mainframe computer systems, and distributed cloud computing environments that include any of the above systems or devices, and the like.

[0073] The present disclosure further relates to a non-transitory computer-readable storage medium configured to store a computer-executable program that causes a computer to perform functions, such as those for implementing the disclosed methods. The computer- readable storage medium may further store the real time data collected by the controller 150 and computer-executable instructions. The storage medium may include a memory and/or any other storage device. The memory may be, for example, random-access memory (RAM) of a computer. The memory may be a semiconductor memory such as an SRAM and a DRAM. The storage device may be, for example, a register, a magnetic storage device such as a hard disk device, an optical storage device such as an optical disk device, an internal or external hard drive, a server, a solid-state storage device, CD-ROM, DVD, other optical or magnetic disk storage, or other storage devices.

[0074] The present disclosure further relates to a method of evaluating a condition of at least one of the first and second light source assemblies 120a, 120b in the fluid treatment system 100. The method may include temporarily stopping or modulating a supply of power to one of the first and second arrays of LEDs 124a, 124b, measuring an intensity of UV light in a state in which the one array of LEDs 124 is temporarily powered at a different or varying level and the other of the first and second arrays of LEDs 124a, 124b is powered on, and determining whether the measured intensity is less than the predetermined value to evaluate a condition of the other light source assembly 120. If the measured intensity is lower than the predetermined value, then a notification may be output indicating that the other light source assembly 120 in which the other array of LEDs 124 (powered on during the measurement) is malfunctioning, as described above. [0075] The method may further include evaluating a condition of the one light source assembly 120 before or after evaluating the condition of the other light source assembly 120. The method may include temporarily stopping or modulating a supply of power to the other of the first and second arrays of LEDs 124a, 124b, measuring an intensity of UV light in a state in which the other array of LEDs 124 is temporarily powered at a different or varying level and the one array of LEDs 124 is powered on, and determining whether the measured intensity is less than a predetermined value to evaluate a condition of the one light source assembly 120. If the measured intensity is less than the predetermined value, then a notification may be output indicating that the one light source assembly 120 in which the one array of LEDs 124 (powered on during the measurement) is malfunctioning or defective and/or may need or benefit from servicing and/or cleaning, as described above. In evaluating the condition of the first and second light source assemblies 120a, 120b, the intensity of UV light may be measured by one or both of the first and second intensity sensors 126a, 126b, as described above.

[0076] Upon determining that the measured intensity obtained in at least one of the above states is lower than the predetermined value, or upon receiving the notification, the method may further include cleaning one or both of the first and second light source assemblies 120a, 120b. For example, the first and/or second light source assemblies 120a, 120b may be cleaned to remove foreign materials that have been fouled on the light source assemblies 120a, 120b during use. This may include cleaning the first and/or second light source units 122a, 122b or parts thereof, including, for example, the windows 132a, 132b and/or the housing 130a, 130b thereof, and/or other parts of the light source assemblies 120a, 120b, such as the mounting arm 146, which may be exposed to the fluid during use. By cleaning the windows 132a, 132b, the UV light from the arrays of LEDs 124a, 124b arranged inside of the light source assemblies 120a, 120b may be transmitted to the fluid, and the UV light transmitted from the respective arrays of LEDs 124a, 124b can reach the intensity sensor 126a, 126b in the opposing light source assembly 120a, 120b for an accurate measurement of the intensity of the UV light. Alternatively or additionally, upon determining that the measured intensity obtained in at least one of the above states is lower than the predetermined value, or upon receiving the notification, the method may include repairing, servicing, or otherwise performing maintenance on one or both of the light source assemblies 120a, 120b, or replacing one or both of the first and second arrays of LEDs 124a, 124b and/or replacing one or both of the first and second light source assemblies 120a, 120b and/or replacing one or both of the first and second light source units 122a, 122b. [0077] Although the above methods are described with respect to an arrangement in which the first and second intensity sensors 126a, 126b are arranged in different light source assemblies 120a, 120b, the above methods may be similarly performed when the intensity sensors 126a, 126b are present together in the same light source assembly 120, as shown in, for example, FIG. 7. As discussed above, the sensors 126a, 126b may be oriented in different directions and/or include different input optics 127 so that the intensities of light reaching the first and second sensors 126a, 126b may differ due to traveling through different layers of fluid, different reflection, different fouling of the window 132, and the like.

[0078] The controller 150 may be programmed to: receive and compare the signals from the first and second intensity sensors 126a, 126b in the same light source assembly 120 and/or monitor the signals from the first and second sensors 126a, 126b over time. Based on the comparison of the signals and/or changes in the signals, the controller 150 may be programmed to determine properties of the fluid flowing through the treatment chamber 110, the reactor 102, and/or the source assembly 120. For example, by comparing and/or monitoring the signals from the first and second sensors 126a, 126b, the controller 150 may be programmed to determine various properties, such as: UV optical absorbance (“UVT”) of the fluid in contact with the source assembly 120, the reflectivity of a surface of the reactor 102, the amount of optical attenuation (fouling) on the window 132, the output of the LEDs 124, the output of another light source assembly in the reactor 102.

[0079] For example, the controller 150 may be programmed to determine whether the window 132 of the light source assembly 120 has become fouled with foreign materials by monitoring the signals from the first and second intensity sensors 126a, 126b. Although the sensors 126a, 126b are oriented differently and/or include different input optics 127 (which can affect the intensities of light measured by the respective sensors 126a, 126b), if the light intensities measured by both sensors 126a, 126b decrease by the same or a substantially similar amount, this can indicate fouling on the UV transparent window 132 of the common light source assembly 120. The controller 150 may be programmed to determine whether the intensities of light measured by the first and second sensors 126a, 126b have decreased by the same or a substantially similar amount, and based on this determination, the controller 150 may be programmed to measure an amount of fouling on the window 132 of the common light source assembly 120. For example, if the light intensities measured by both sensors 126a, 126b decrease below a predetermined value, as discussed above, the controller 150 may determine that the window 132 has become fouled with foreign materials and may output a notification so that the window 132 can be cleaned to improve efficiency. The predetermined value may be any suitable predetermined value, including those discussed above with respect to the embodiments in which the intensity sensors 126a, 126b are arranged in different light source assemblies 120a, 120b.

[0080] The controller 150 may additionally or alternatively be programmed to determine whether a surface in the reactor 102 has become fouled with foreign materials. For example, an intensity sensor 126 (e.g., one of the first and second intensity sensors 126a, 126b) may be oriented and/or include input optics 127 so as to receive light primarily comprised of light that has been reflected from a surface in the reactor 102, such as a reflective surface of the treatment chamber 110. The controller 150 may be programmed to monitor the signal from the intensity sensor 126. If the intensity of light measured by the intensity sensor 126 decreases below a predetermined value (such as that discussed above), the controller 150 may determine that the reflective surface has become fouled with foreign materials. The controller 150 may be programmed to output a notification so that the reflective surface can be cleaned to remove fouling materials that have accumulated thereon and optimize the system.

[0081] The controller 150 may additionally or alternatively be programmed to determine the optical absorbance or UVT of the water flowing through the reactor 102. For example, the first and second intensity sensors 126a, 126b may be oriented and/or include input optics 127 so that light reaching the two sensors 126a, 126b passes through two different water layers. The controller 150 may be programmed to compare the signals from the two intensity sensors 126a, 126b. The difference in signals (intensities of light measured by the two sensors 126a, 126b) is a result of intensity attenuation by that different layer. Based on the difference in the measured intensities of light, the controller 150 may be programmed to determine the optical absorbance or UVT of that incremental layer.

[0082] The controller 150 may additionally or alternatively be programmed to determine and/or monitor the output of light from one or more of the LEDs 124 in the light source assembly 120a. For example, an intensity sensor 126 e.g., one of the intensity sensors 126a, 126b) may be oriented and/or include input optics 127 so that the light reaching that sensor 126 is primarily from light reflected within the source assembly 120, or directly emitted from an LED 124. The controller 150 may be programmed to monitor the signal from the sensor 126. If the signal decreases, the controller 150 may determine that the output of one or more of the LEDs 124 has decreased. Because the sensor 126 is oriented and/or includes input optics 127 so as to primarily receive light reflected within the source assembly 120 and/or directly emitted from an LED 124, the decrease in the light intensity measured by that senor 126 can be separated from any outside effects, such as fouling or UVT. Thus, by orienting and/or configuring the input optics 127 of one or more sensors 126 to measure the intensity of light from the LEDs 124, the health of the LEDs 124 can be monitored to ensure that sufficient UV light is being transmitted to the fluid flowing through the reactor 102 and/or to detect whether maintenance, repairs, and/or replacement may be beneficial. For example, the controller 150 may be configured to monitor the intensity of light measured by the sensor 126 and determine whether the intensity of light measured by the sensor 126 falls below a predetermined value, which may be any suitable predetermined value, including those discussed above with respect to the embodiments in which the intensity sensors 126a, 126b are arranged in different light source assemblies 120a, 120b.

[0083] The controller 150 may be further programmed to output a notification based on the determined property or properties, in a similar manner as described above. For example, if the controller 150 determines that one or more of the properties indicates that a component (e.g., LEDS 124, light source assembly 120, sensor, or the like) of the system 100 is malfunctioning, the controller 150 may be configured to output a notification, for example, in the form of a sound, light, or other error message. The notification may indicate that the component is malfunctioning and/or the notification may identify the determined property. For example, if the controller 150 determines that the UVT is too low, this may indicate a problem with the light source assembly 120, such as a problem with the LEDs 124. The output notification may indicate, instruct, or suggest that the component may need or benefit from servicing or maintenance, for example, to fix a problem, such as an electrical or other problem with the light source assembly 120 or other component, it may indicate that the component, such as the light source assembly 120 and/or the LEDs 124, should be replaced, or it may be indicate that the light source assembly 120 (e.g., the window 132) or other component, such as a reflective surface of the reactor 102, may need or benefit from being cleaned to remove fouling materials that have accumulated on the light source assembly 120, for example, on the window 132 of the light source unit 122 and/or on the reactor 102. As discussed above, the controller 150 may monitor and/or periodically compare the signals received from the first and second intensity sensors 126a, 126b in the same light source assembly 120 to determine properties of the fluid and/or a component of the system 100, or the controller 150 may perform such evaluation upon a trigger, such as a system trigger or input from a person operating the system.

[0084] Although embodiments disclosed herein have been described with respect to treating water and/or aqueous fluids with UV radiation treatment, the present disclosure is not limited to water and aqueous fluids, and may be used to treat any fluid, including liquids, vapors, gels, plasmas, and gases. Similarly, the present disclosure is not limited to residential UV treatment systems, and may be applied to industrial, municipal, and commercial systems.

[0085] It will be appreciated that the above-disclosed features and functions, or alternatives thereof, may be desirably combined into different systems and methods. Also, various alternatives, modifications, variations or improvements may be subsequently made by those skilled in the art, and are also intended to be encompassed by the disclosed embodiments. As such, various changes may be made without departing from the spirit and scope of this disclosure.

Claims

WHAT IS CLAIMED IS

1. A fluid treatment system for treating a fluid with ultraviolet (UV) light, the system comprising: a reactor including a treatment chamber that is configured to receive a flow of the fluid; first and second light source assemblies respectively including first and second arrays of light-emitting diodes (LEDs) that are configured to emit UV light into the treatment chamber to treat the fluid, the first and second light source assemblies being arranged so that the first array of LEDs faces the second array of LEDs in the treatment chamber; and first and second intensity sensors that are respectively supported by the first and second light source assemblies and are configured to measure an intensity of UV light incident thereon.

2. The fluid treatment system according to claim 1, wherein the first and second arrays of LEDs are arranged to face each other along a longitudinal axis of the treatment chamber.

3. The fluid treatment system according to claim 1, wherein: the first and second light source assemblies each include a housing, the first array of LEDs and the first intensity sensor are arranged in the housing of the first light source assembly, and the second array of LEDs and the second intensity sensor are arranged in the housing of the second light source assembly.

4. The fluid treatment system according to claim 3, wherein: the housing of each of the first and second light source assemblies further includes a UV transparent window, the UV transparent window of the first light source assembly is arranged to cover the first array of LEDs and the first intensity sensor, and the UV transparent window of the second light source assembly is arranged to cover the second array of LEDs and the second intensity sensor.

5. The fluid treatment system according to claim 3, wherein: the first and second light source assemblies each further include a circuit board arranged in the housing, the first array of LEDs and the first intensity sensor are mounted on the circuit board in the first light source assembly, and the second array of LEDs and the second intensity sensor are mounted on the circuit board in the second light source assembly.

6. The fluid treatment system according to claim 1, wherein the first and second light source assemblies are configured to be in contact with the fluid flowing through the treatment chamber.

7. The fluid treatment system according to claim 1, further comprising a controller configured to temporarily modulate a supply of power to one of the first and second arrays of LEDs while supplying power to the other of the first and second arrays of LEDs.

8. The fluid treatment system according to claim 7, wherein the controller is further configured to receive a signal corresponding to a measured intensity of UV light from at least one of the first intensity sensor and the second intensity sensor in a first state in which the first array of LEDs is powered on and the second array of LEDs is temporarily modulated.

9. The fluid treatment system according to claim 8, wherein the controller is further configured to determine whether the measured intensity of UV light in the first state is different from a predetermined value.

10. The fluid treatment system according to claim 9, wherein the controller is further configured to output a notification if the measured intensity of UV light in the first state is different from the predetermined value.

11. The fluid treatment system according to claim 9, wherein the controller is further configured to: receive a signal corresponding to a measured intensity of UV light from at least one of the first intensity sensor and the second intensity sensor in a second state in which the second array of LEDs is powered on and the first array of LEDs is temporarily modulated; and determine whether the measured intensity of UV light in the second state is different from a predetermined value.

12. The fluid treatment system according to claim 11, wherein the controller is further configured to: output a notification if the measured intensity of UV light in the second state is different from the predetermined value.

13. A method of evaluating a condition of at least one of the first and second light source assemblies in the fluid treatment system according to claim 1, the method comprising: measuring an intensity of UV light in a first state in which the first array of LEDs is powered on and the second array of LEDs is temporarily modulated; and determining whether the intensity of UV light measured in the first state is different from a predetermined value.

14. The method according to claim 13, further comprising: outputting a notification indicating that the first light source assembly is malfunctioning if the intensity of UV light measured in the first state is different from the predetermined value.

15. The method according to claim 13, wherein the intensity of UV light measured in the first state is measured by at least one of the first intensity sensor and the second intensity sensor.

16. The method according to claim 13, further comprising: if the intensity of UV light measured in the first state is different from the predetermined value, performing at least one of: cleaning the first light source assembly, repairing the first light source assembly, and replacing the first light source assembly.

17. The method according to claim 13, further comprising: measuring an intensity of UV light in a second state in which the second array of LEDs is powered on and the power to the first array of LEDs is temporarily modulated; and determining whether the intensity of UV light measured in the second state different from a predetermined value.

18. The method according to claim 17, further comprising: outputting a notification indicating that the second light source assembly is malfunctioning if the intensity of UV light measured in the second state is different from the predetermined value.

19. The method according to claim 17, wherein the intensity of UV light measured in the second state is measured by at least one of the first intensity sensor and the second intensity sensor.

20. The method according to claim 17, further comprising if the intensity of UV light measured in the second state is different from the predetermined value, performing at least one of: cleaning the second light source assembly, repairing the second light source assembly, and replacing the second light source assembly.

21. A light source assembly comprising: one or more light-emitting diodes (LEDs) able to emit ultraviolet (UV) light; a UV transparent window; and a first intensity sensor and a second intensity sensor that are oriented differently from each other or include different input optics.

22. The light source assembly according to claim 21, wherein the different input optics include a lens, a mirror or reflective surface, an aperture, a hollow tube, a diffuser, a transparent rod, or a combination thereof.