Ultraviolet irradiation apparatus with integral thermal transfer element

Abstract

An irradiation apparatus having an interior irradiation reactor and a UV-LED emitting source configure to emit UV light through an opening in a lower wall of the irradiation chamber, a first liquid port and a second liquid port for liquid flow into and out of the irradiation reactor. A first connection port connects to either a liquid supply source or a liquid usage device, and consists of a metal tubing with an outer sidewall with a flattened portion along its length. The flattened portion of the outer sidewall of the metal tubing provides a thermal contact surface that when placed into confronting contact with a heat-emitting surface of the UV-LED source provides a heatsink for the heat generated by the UV-LED source.

Description

Attorney docket: AST-011 -PCTULTRAVIOLET IRRADIATION APPARATUS WITH INTEGRAL THERMAL TRANSFER ELEMENTFIELD OF THE INVENTION

[0001] The present invention relates generally to apparatus and methods for disinfection of fluids by irradiation. More specifically, the invention relates to an apparatus and methods for disinfection of liquids containing a contaminant or pathogen to be irradiated with a UV radiation source.BACKGROUND OF THE INVENTION

[0002] The use of ultraviolet (UV) radiation for the purpose of disinfection of a fluid, including liquids and gases, is well known. The process of using ultraviolet radiation to inactivate microbial contaminants in fluids is referred to as Ultraviolet Germicidal Irradiation (UVGI). Ultraviolet radiation has also been used for oxidizing organic and inorganic materials in a fluid, termed Advance Oxidation Process (AOP), and many commercial AOP systems are in use today. Systems employing UVGI and AOP methods rely on the ability to transmit UV radiation into the fluid in a predictable manner. The dose of a UVGI system, which has units of J / cm2, can be simply stated as the product of the UV irradiance in units of W / cm2and the exposure time in seconds.

[0003] There are many types of UV radiation sources. Solid state sources such as LEDs create light in a semiconductor material through charge recombination in an active layer where charge injection is applied to an anode and cathode of the semiconductor heterostructure. Solid state radiation sources have maximized outputs at lower ambient temperatures. For example, the output power of a low-pressure mercury lamp may peak at an ambient temperature of 40 degrees Celsius while the optical output power of a 265nm light emitting diode (LED) displays a linear relationship with ambient temperature. The slope of the LED curve may vary by the device design, but the trend remains the same with larger optical output powers seen at lower ambient temperatures.

[0004] Many LED manufacturers specify a maximum junction temperature which should not be exceeded. The LED junction temperature is the temperature of the active layer sandwiched between the n-type and p-type semiconductor layers of the LED. Exceeding a maximum rated junction temperature may result in a decrease in the lifetime or other characteristics of the LED. In a simplified model, an LED can be represented as a series of thermal resistances.Attorney docket: AS T-011-PC T

[0005] LEDs are unique among most UV sources in that heat is removed through the side of the chip which is electrically connected versus the side which is responsible for most of the UV emission. However, LEDs can be sensitive to electro-static discharge, moisture, and ambient gases like oxygen or nitrogen which can degrade the performance of the LED electrical contacts and the semiconductor. For this reason, a LTV-light transmissive window, for example, a quartz window, is often placed on the SMD package of a LED. In UVGI systems where the LED will be protected from the fluid via a window, the window on the SMD becomes superfluous if the above environmental impacts can be mitigated. A single window over a board containing one or more LEDs can be used as the optical window for a fluid disinfection system if the LEDs are sealed between the board and the window such that the window can serve as a portion of the pressure vessel for the disinfection system and to segregate the LEDs from the fluid. Potting compounds like epoxies, silicones, or sealing gaskets or O-rings can be used between the board and the window to accomplish this. The potting may be undertaken in a low relative humidity environment or even purged with dry air or an inert gas to ensure any voids between the LED and window do not have undesirable moisture or gases inside. This would also increase the output power of the LED since it would pass light through one quartz window versus two. An additional benefit to this type of single window lamp package is that the LED imparts little heating to the window, in contrast to mercury vapor sources which transmit a large amount of heat to the window. Lower window temperatures have been correlated to less fouling of the window. Window fouling lowers the overall UV transmittance of the window, which in turn lowers the performance of UVGI and AOP systems. Thus, a robust product design utilizing a UV source will account for the temperature of the UV source during operation by consideration of heat transfer. By such methods the lifetime and output power of the UV source may be better controlled. In addition, methods of assembling the UV source into secondary packaging can be used to enhance the output power and lifetime of the UV source.

[0006] While the UV source is an important component in a UVGI system, it is only one component in the overall system efficiency. The system efficiency can be expressed as the product of the reactor efficiency and the UV source efficiency. It is good practice in the design of a UVGI system to maximize the exposure time, often termed the “residence time”, of the fluid to the UV irradiance thereby maximizing the dose seen by the fluid. The reactor efficiency is a combination of the residence time efficiency and the optical efficiency. The optical efficiency of the reactor isAttorney docket: AS T-011 -PC T a measure of how effectively the reactor uses photons from the UV source to increase the probability that a microbial contaminant in the fluid will absorb a photon.

[0007] Water security is a worldwide problem due to cost, infrastructure, and availability. In locations with less water security, water quality is often also a problem. The microbial safety of the water can be lower than recommended for human consumption in these areas. There exist UV technology solutions integrated into point of use treatment products, however these systems use gas discharge mercury' vapor lamps.

[0008] There nevertheless remains a need for a low cost, mercury-free and effective product to improve the microbial safety of the water in these locations. The United Nations has ratified the Minimata convention with the goal of eliminating mercury from all products including UV treatment systems. The cost of a system includes both materials and labor cost. The efficiency of a product is comprised of the system efficiency and operational efficiency. The system efficiency is comprised of the hydraulic efficiency which accounts for the retention time of the fluid in the system and the optical efficiency which describes the probability for a photon to be absorbed by' a pathogen in the fluid. The operation efficiency is dependent on the product operational usage (is it on intermittently or constantly') and the electrical efficiency of the product.

[0009] U. S. Patent Application Publications 2012 / 0318749 Al, 2014 / 0161664 Al, and 2014 / 0240695 Al, and U. S. Patent 10,500,295, all incorporated herein by reference, disclose various apparatus, materials and methods useful herein for disinfection of fluids by means of a U V irradiation source that can include UV-emitting light emitting diodes (LEDs).

[0010] Nevertheless, there remains a need for an improved apparatus and method for irradiation that provides good system efficiency, incorporates adequate cooling, and can be used with a variety of housings or flow cells, all while maintaining a compact footprint.SUMMARY OF THE INVENTION

[0011] The present invention provides an apparatus and method for an ultraviolet irradiation apparatus having an integral thermal transfer element, that balances system efficiency with system cost by using a unique hydraulic design with an optically efficient irradiation chamber that can be manufactured using simple machining steps. The present invention also uses a mercury-free ultraviolet irradiation source and improved and effective thermal management.Attorney docket: AST-011 -PCT

[0012] More particularly, the present invention provides an apparatus having a liquid connection port consisting of a metal tubing having a thermal contact surface on an outer sidewall that is configured to be placed into confronting thermally-conducting contact with heat-emitting surface of the UV radiation source, thereby providing a heatsink for, or improving a heatsink of, the UV radiation source.

[0013] The present invention provides an irradiation apparatus comprising: (i) an interior irradiation reactor, a first liquid port and a second liquid port for liquid flow into and out of the irradiation reactor; (ii) a UV radiation source configure to emit UV light through an opening in a lower wall of the irradiation chamber, the UV radiation source having a heat-emitting surface; and (iii) a first connection port for connection to either a liquid supply source or a liquid usage device, the first connection port consisting of a metal tubing comprising an outer sidewall, a portion of the outer sidewall comprising a thermal contact surface disposed in confronting contact with the heatemitting surface of the UV radiation source, thereby providing a heatsink for the UV radiation source.

[0014] The present invention also provides an irradiation apparatus comprising: (i) an irradiation chamber for a liquid containing a contaminant to be irradiated, the irradiation chamber having an interior irradiation reactor, a first liquid port and a second liquid port for liquid flow into and out of the irradiation reactor; (ii) a UV radiation source configured to emit UV light through an opening in a lower wall of the irradiation chamber, the UV radiation source having a heatemitting surface; and (iii) a first connection port for connection to either a liquid supply source or a liquid usage device, the first connection port consisting of a metal tubing comprising an outer sidewall, a portion of the outer sidewall comprising a thermal contact surface disposed in confronting contact with the heat-emitting surface of the UV radiation source, thereby providing a heatsink for the LTV radiation source.

[0015] hr various embodiments, the material of the metal tubing can be selected from the group consisting of copper, silver, nickel, zinc, stainless steel, aluminum, and an alloy thereof. In some embodiments, the metal tubing is copper tubing.

[0016] In various embodiments, the UV radiation source is one or more light emitting diodes (LEDs). In some embodiments, the EEDs are mounted on a printed circuit board (PCB).

[0017] hi various embodiments, the PCB is a metalcore PCB (MCPCB).Attorney docket: AS T-011 -PC T

[0018] In various embodiments, the thermal contact surface of the metal tubing is in direct thermal contact with the heat-emitting surface of the UV radiation source.

[0019] In various embodiments, the irradiation apparatus includes a means for compressing the thermal contact surface against the heat-emitting surface of the UV radiation source or the PCB.

[0020] hi various embodiments, a thermal interface material can be placed between the thermal contact surface and the heat-emitting surface of the PCB or the U V radiation source. Non-limiting examples of a thermal interface material can include a grease, a paste, a gel, or a pad.

[0021] In various embodiments, the surface of the PCB at which the LEDs are fixed can include one or more thermal vias. A thermal via is a heat-conducting metallic cylinder, barrel, or solder-filled barrel, positioned just below the heat-generating component, that reduces thermal resistance from the upper surface of the PCB to the bottom, heat-emitting surface.

[0022] In various embodiments, the ratio of the lateral width of the thermal contact surface to the outer diameter of the metal tubing is about 0.6 to 0.9:1, and preferably about 0.78 to 0.82:1.

[0023] In various embodiments, the radial distance from a centerline of the metal tubing to the thermal contact surface is 55-85%, preferably about 65%-70%, of the outer radius of the metal tubing.

[0024] In various embodiments, the metal tubing includes a distal transfer segment having an opening formed through the cylindrical wall, for placing the metal tubing in liquid communication with the irradiation chamber.

[0025] In various embodiments, the metal tubing includes a distal transfer segment having a transverse opening formed through the cylindrical wall perpendicular to axial centerline of the distal transfer segment, for placing the metal tubing in liquid communication with the irradiation reactor.

[0026] In various embodiments, the transverse opening is a circular bore having a diameter of about 75-100% of, and preferably the same as, an inside diameter of the distal transfer segment.

[0027] In other embodiments, the transverse opening can be a lateral slit or other shaped opening.

[0028] In various embodiments, the irradiation has a capsule shape.

[0029] In various embodiments, the first liquid port is disposed in the lower wall of the irradiation reactor, and the second liquid port is disposed in an upper wall of the irradiation reactor.Attorney docket: AST-011 -PCI'

[0030] In various embodiments, the first liquid port is oriented along a tangential path from the axial centerline of the irradiation reactor.

[0031] In various embodiments, the first liquid port is oriented along a chord path through the circular cross-section of the irradiation reactor spaced away from the centerline and toward the periphery of the reactor.

[0032] In various embodiments, the irradiation chamber consists of: i) a base body that includes a lower portion of the irradiation reactor, a means for positioning a U V-light transmissive window in the lower portion of the irradiation reactor, at least a portion of the first liquid port, and a transfer port for placing the first connection port in liquid communication with the first liquid port of the irradiation reactor, and ii ) a chamber body that has an interior cavity that consists of a remaining portion of the irradiation reactor and the second liquid port.

[0033] In another embodiment, the irradiation chamber further consists of iii) a cover that includes the second connection port positioned in liquid communication with the second liquid port.

[0034] In various embodiments, the UV-light transmissive window can be made of quartz, sapphire, or a principally UV-transparent polymer. In some embodiments, the UV-light transmissive window is a quartz window.

[0035] In various embodiments, the UV-light transmissive window is secured within a window plug that is inserted into the lower portion of the irradiation reactor. In some embodiments, window' plug includes a means for compressing a peripheral seal of the UV-light transmissive window to provide a fluidic seal for a liquid passing through the apparatus.

[0036] In some embodiments, the base portion is configured to be engaged with the chamber body in only one axial rotational position.

[0037] The present invention provides an apparatus and method wherein the heat-emitting surface of a UV radiation source, typically a light emitting diode (LED), is cooled by a liquid supply tubing, made of a metal through which the liquid supply passes to or from the irradiation reactor into which the UV radiation is emitted. In one preferred embodiment, the liquid is water and the metal is copper. The increased thermal transmissivity of the metal of the metal tubing improves cooling and thermal transfer from the heat-emitting surface of the UV radiation source, as compared to an embodiment where the cooling is provided by direct contact of the suppliedAttorney docket: AST-011 -PCT liquid with the heat source, such as is described in US Patent 10,500,295, the disclosure of which is incorporated by reference in its entirety.

[0038] The invention also provides an irradiation apparatus and method comprising: an irradiation chamber for a liquid containing a contaminant to be UV irradiated, the irradiation chamber having an internal irradiation reactor, an inlet port and an outlet port for liquid flow into and out of the irradiation reactor; a UV radiation source in UV irradiation communication with the irradiation reactor; and metal tubing for liquid delivery to or from the irradiation apparatus, the metal tubing comprising a thermal contact surface thermally coupled to the UV radiation source. Preferably the UV irradiation source comprises an LED mounted to a PCB, and the thermal contact surface provides a heatsink in thermal contact with the heat-emitting surface of the PCB.BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The invention is illustrated and described herein with reference to the various drawings, in which like reference numbers are used to denote like apparatus components, as appropriate, and in which:

[0040] Figure 1 is a perspective view of an irradiation apparatus of the invention.

[0041] Figure 2 an exploded view of an irradiation apparatus.

[0042] Figure 3 is a longitudinal sectional view of the irradiation apparatus taken along line 3- 3 of Figure 1 .

[0043] Figure 4 is a detailed view of a portion of the Figure 4 is a transverse sectional view of the irradiation apparatus taken along line 4-4 of Figure taken from Figure 3.

[0044] Figure 5 is a transverse sectional view of the irradiation apparatus taken along line 5-5 of Figure 1.

[0045] Figure 6 is a plan view of the irradiation apparatus taken along line 6-6 of Figure 1.

[0046] Figure 7 is a perspective view of a chamber body separated and angled from a base body of the irradiation apparatus.

[0047] Figure 8 is an exploded, perspective view of an alternative embodiment of a base body having an insertable window plug.

[0048] Figure 9 is perspective view of an underside of the insertable window plug.

[0049] Figure 10 is a vertical sectional view of the inserted window plug through line 10-10 of Figure 8.Attorney docket; AST-011 -PCT

[0050] Figures 11 and 12 are perspective upper and lower views, respectively, of a installation tool for inserting the window plug into the base body.DETAILED DESCRIPTION OF THE INVENTION

[0051] When describing the apparatus and its bodies, parts, elements, and features, the terms “upper” (or “top”) and “lower” (or “bottom”) are used as a convenience in identifying the relative positions of the bodies, parts, elements and features as illustrated in the drawings. It should be understood that in a normal use, the apparatus can be oriented as illustrated in the drawing, with an “upper” body, part, element or feature oriented vertically upward and a “lower” body, part, element or feature oriented vertically downward; or in the opposite orientation, with an “upper” body, part, element or feature oriented vertically downward and a “lower” body, part, element or feature oriented vertically upward; or in a transverse position, with both the “upper” and “lower” body, part, element or feature oriented horizontally; or any omnidirectional orientation.

[0052] The reactor body 10 is the upper body, and the coolant body 31 is the lower body.

[0053] Figure 1 shows a perspective view of the irradiation apparatus 1 , featuring an irradiation chamber 10, an ultraviolet (UV)-source electronics housing assembly 80, and a metal tubing 70.

[0054] Figure 2 shows an exploded view of main components and supporting elements of the irradiation apparatus 1, including an irradiation chamber 10, a base assembly 20 having a base body 21 and a transition connection 32, a chamber body 40, a cover body 60, the metal tubing 70, a tubing guide 78, and an electronic housing assembly 80. cmetal tubing>

[0055] A cooling means for the L'V radiation source is a length of metal tubing 70. The length of the metal tubing includes a connection segment including a first connection port 11 for attachment to a liquid supply system or a liquid usage device, an intermediate heat transfer segment 71 , and a distal transfer segment 74. The intermediate heat transfer segment 71 includes an outerwall surface that can be placed into thermal contact, and preferably into direct thermal contact, with a heat-emitting surface 84 of a UV radiation source.

[0056] In various embodiments, the liquid is water, and a liquid supply system is typically a copper piping that connects a water supply system (by non-limiting example, a municipal waterAttorney docket: AS T-01 1 -PC T system, tank, reservoir, or integrated water server consisting of a pump) to a water usage device (by non-limiting example, a sink, faucet or spigot).

[0057] The intermediate heat transfer segment 71 includes a thermal contact surface 73 formed on an arc portion of the surface of the outer wall 72. Preferably, the thermal contact surface 73 is a planar surface, having a length extending parallel to, and a width transverse and perpendicular to, the centerline 100 of the metal tubing 70.

[0058] The flattening of the outer wall 72 in the intermediate heat transfer segment 71 to form the thermal contact surface 73 can be performed by placing a tubular mold inside the copper tubing having a planar arc surface extending normally and along the centerline of the metal tubing. A planar thermal contact surface 73 is formed by compressing the tubing wall against the planar arc surface of the tubular mold.

[0059] The axial length of the thermal contact surface 73 is typically sufficient to not only span across an underside of the UV radiation source, such as an LED, but typically also across a printed circuit board (PCB) on which the LED is affixed.

[0060] The ratio of the axial length of the thermal contact surface to the outer radius of the metal tubing is typically at least 1: 1, and can be up to 6: 1 or more.

[0061] A ratio of the radial distance (Rte) from the centerline 100 of the thermal contact surface to the outer surface (Ros) of the wall 72 of the metal tubing 70 is 0.55-0.85: 1, and preferably about 0.65-0.70: 1 .

[0062] Transition segments 75a and 75b connect the opposite ends of the heat transfer segment71 to the connection segment and the distal transfer segment 74, respectively.

[0063] In various embodiments, the distal transfer segment 74 includes a transverse opening 76 for the water to exit the metal tubing and enter the base body 21 of the irradiation chamber. The transverse opening 76 allows the water to exit (or to enter) the metal tubing 70 at a right angle (perpendicular) to the longitudinal centerline 100 of the metal tubing.

[0064] In a preferred embodiment, a transverse opening 76 is formed through the cylindrical wall, and has an axial transfer port centerline 103 oriented substantially perpendicular to the tubing centerline 100 through the distal transfer segment 74. In some embodiments, the transverse opening 76 is a circular bore formed normal to the tubing centerline 100 of the distal transfer segment 74, for example by circular drilling. As shown in Figures 3 and 4, the transverse openingAttorney docket: AST-011 -PCT76 is oriented to align and fluidly communicate with a transfer port 31 in the base body 21 of the irradiation chamber 10.

[0065] The diameter of the transverse opening 76 is typically about 75-100% of, and preferably is the same as, the inside diameter of the metal tubing 70. Typically the opening is as large as possible to reduce liquid pressure loss.

[0066] In some embodiments, the distal transfer segment 74 has an end opening 77 defined by the peripheral edge of the outer wall 72. The end opening 77 can be sealed, though preferably the end opening 77 can be placed into a ‘"dead end” of the elbow segment 34, with the end opening 77 in direct contact with an end wall 35 of the elbow segment 34. Sealing of the end opening 77 itself is not required because a cavity into which the end opening opens is itself in fluid communication with the transfer port 31 , and / or is sealed off; for example, egress of liquid from the transition connection 32 is prevented by the O-ring seal 90 as shown in Figure 3. This allows the metal tubing 70 to be fully inserted axially into the transition connection 32.

[0067] The thermal contact surface 73 is preferably formed along the same longitudinal line of the metal tubing as the transverse opening 76, so that both are oriented in the same radial direction. The axial distance between the edge of the thermal contact surface 73 and the end opening 77 is provided to match the horizontal distance between the edge of the PCB 52 and the transfer port 31 , to ensure that when the heat-emitting surface of the PCB is registered and aligned with the thermal contact surface 73 of the metal tubing 70, the distal end 77 of the distal transfer segment 734 extends fully into the transfer port endwall 35.

[0068] In some embodiments, a thermal interface material 94 is placed between the thermal contact surface 73 and the heat-emitting surface, for example, the PCB, to improve heat transfer to the thermal contact surface 73.<irradiation chamber>

[0069] hr various embodiments, the irradiation chamber 10 can include two or more separate body portions that are placed and secured together to form a unitary body comprising an irradiation reactor 55.

[0070] In the illustrated embodiment, the base assembly 20 of the irradiation chamber 10 is a base body 21 that includes a lower chamber portion 26, and a transition connection 32 forAttorney docket: AST-011 -PCT providing liquid communication between the first connection port 11 and the irradiation reactor 55.

[0071] The intermediate body portion of the irradiation chamber 10 is a chamber body 40 that includes a domed cavity 46 that provides an upper portion of the irradiation reactor 55 and an upper liquid port 50.

[0072] The upper body portion of the irradiation chamber 10 is a cover body 60 including a second connection port 12 to provide liquid communication with the upper liquid port 50 of the chamber body 40.<base body>

[0073] The base assembly 20 includes the base body 21 , a cylindrical sidewall 22 extending axially from an upper surface of the periphery of the base body 21, and a transition connection 32 formed integrally on the underside of the base body 21, to provide liquid communication between the metal tubing 70 and the base body 21.

[0074] The base body 21 includes a transition floor 23 and a lower chamber portion 26 that extends axially upward from the transition floor 23 of the base body 21. The lower chamber portion 26 has a cylindrical outer sidewall 29, and a concave surface 30 that increases in radius, from an axial chamber centerline 102 of the concave surface 30, to an upper end at the rim 28. The bottom end of the lower chamber portion 26 has a circular opening formed into the concave surface 30 and a window well 69 for placement and sealed securing of the quartz window 96 and for the passage of UV light from the LED(s) or equivalent light source into the reactor 55.

[0075] A tangential port 27 introduces the flow of water tangentially into the lower chamber portion 26 of the irradiation chamber 55. The tangential port 27 extends through the outer sidewall 29 and enters along a centerline 104 of the tangential port 27 extending tangential to the chamber centerline 102.

[0076] The flow of liquid along the tangential port 27 generates a swirling, circular pattern of water flow within the lower, middle and upper sections of the irradiation chamber 55, and in communication with the upper liquid port 50 in the upper section. Whether the liquid flows into or out of the irradiation chamber through the tangential port 27, a swirling pattern of the liquid flow within the irradiation chamber 55 is induced.Attorney docket: AST-011 -PCT

[0077] The cylindrical sidewall 22 of the base assembly 20 forms a cylindrical cavity into which the chamber body 40 (described below) is placed, and over which the cover body 60 is placed and secured. As illustrated in Figure 4, the volume or space between the transition floor 23 of the base body 21 and the lower surface 44 of the chamber body 40, and outside the outer sidewall 29 of the lower chamber portion 26, form the boundaries of a coolant transfer corridor 39 that provides liquid communication for the movement of liquid (water) between the tangential port 27 of the irradiation chamber 55, and a transfer port 31 formed through the transition floor 23 of the base body 21 and into the transition connection 32.

[0078] In some embodiments, and as illustrated in Figure 7, an upper portion 51 of the tangential port 27 can be formed into the lower surface 44 of the chamber body 40, to ensure adequate liquid flow' tangentially into (or out of) the lower section of the irradiation chamber 55.

[0079] The transition connection 32 is formed integrally with the underside of the base body 21 and provides for liquid communication between the transfer corridor 39 and the metal tubing 70. The transition connection 32 includes an elbow segment 34 including an upper vertical channel 33 in liquid communication with the transfer port 31, and a lower horizontal channel 38. The lower horizontal channel 38 includes a distal flare segment 36 that forms a stop shoulder 37.

[0080] The illustrated embodiment also includes a tubing guide 78. The tubing guide 78 includes a slotted cylindrical proximal end 79a, a slotted cylindrical distal end 79b, and a semi- cylindrical intermediate segment 86 between the two ends 79a, 79b. Both the slotted cylindrical proximal end 79a and the slotted cylindrical distal end 79b have an axial slot 85 of a narrow' arc w'idth (about 10-15 arc degrees) that allow the separated edges to be forced toward or apart from the other by a biasing force.

[0081] The tubing guide 78 is formed integrally with a housing base tray 87. The housing base tray 87 includes a flat tray surface for placement of an electronic PCB board 52, and is covered with a housing cover 81.

[0082] The housing base tray 87 is formed of two laterally-separated rectangularly-shaped half trays 87a, 87b. The tw'o half trays 87a, 87b are attached along a joint edge 68 to the opposite, axially-extending wall edges of the semi-cylindrical intermediate segment 86. The tw'o half trays 87a, 87b form the lateral wings of the rectangular housing base tray 87, separated by the space between the joint edges 68. The two rectangularly-shaped half trays 87a, 87b include a peripheralAttorney docket: AS T-011-PC T wall along their respective other three edges, providing a rectangular space for placement of a PCB. Opposed pairs of retaining clips 83 retain the PCB 52 to the housing base 87.

[0083] The design of the tubing guide 78 pennits the two base trays 87a, 87b to flex and pivot at their joint edges 68 around the centerline 100 of the tubing guide 78.

[0084] The tubing guide 78 has a cylindrical passageway along the centerline 100. During assembly of the apparatus 1, the metal tubing 70 is inserted through tire cylindrical passage way, with the first connection port of the metal tubing 70 extending from the slotted cylindrical proximal end 79a, the distal transfer segment 74 extending from the slotted cylindrical distal end 79b, and the intermediate heat transfer segment 71 of the metal tubing 70 centered along the semi- cylindrical intermediate segment 86 of the tubing guide 78, with the thermal contact surface 73 of the metal tubing 70 registered within the opening between, and elevated slightly above, the joint edges 68 of the intermediate segment 86.

[0085] The LED 53 is attached along the longitudinal centerline of the PCB 52, so thatthe undersurface of the PCB is placed immediately below the LED 53 into a position confronting and registered with the intermediate heat transfer segment 71 of the metal tubing 70.

[0086] A housing cover 81 is then placed over the housing base tray 87 to cover the PCB 52 and other electronic components. The housing cover 81 has two integrally-formed half covers 81 a, 81 b, each half cover including a peripheral wall along their respective three edges, and having a pair of opposite, axially-separated arched openings 89 separating the side walls of the half covers 81a,81b. The arched openings 89 accommodate and prevent contact with the respective proximal and distal ends 79a, 79b of the tubing guide 78, and allow the housing cover 81 to flex along its longitudinal center.

[0087] The assembled electronics housing assembly 80 with the attached tubing guide 78 is then positioned against the underside of the base body 21 while inserting the distal end 79 of the tubing guide 78 into the flare segment 36, which then engages the stop shoulder 37 of the transition connection 32, forming a seal with the stop shoulder 37 with the tubing O-ring 90. An end of the distal transfer segment 74 of the metal tubing 70 extends through the horizontal channel 38 of the elbow segment 34, to confront or engage the end wall 35 of the transition connection 32.

[0088] Additionally, the opening 88 in the housing cover 81 above the LED 53 is placed into alignment and registry with an opening 67 in the bottom of the base body 21, along the axial centerline 102 of the quartz window 96 and the irradiation reactor 55.Attorney docket: AST-011 -PCT

[0089] A pair of fasteners, illustrated as screws 82, are then inserted through through-holes in the housing tray 87, PCB 52, and the housing cover 81, and are threaded into the undersurface of the base body 2 Ito secure the electronics housing assembly 80 to the base body21 .

[0090] The secure threading of the securements (screws) into the base body 21 also draws the electronics housing assembly 80, the guide 78, and in particular the metal tubing 70 and its thermal contact surface 73 upward into the PCB, thereby compressing the thermal contact surface 73 against the undersurface, and the heat-emitting surface, of the PCB, to improve heat transfer. The “drawing up” of the two halves 87a, 87b of the base tray also causes the proximal and distal ends 79a, 79b of the tubing guide 78 to be compressed together, narrowing the slot 85, and tightening the proximal and distal ends 79a, 79b against the proximal segment and distal transfer segment 74 of the metal tubing 70, thereby securing together and maintaining rotational alignment and positioning between the base body 21, the metal tubing 70 , LED(s) 53 , and heat-emitting surface 84.<chamber body>

[0091] The chamber body 40 comprises a cylindrical body having a domed cavity formed into a lower surface that provides a majority portion of the irradiation chamber.

[0092] In the illustrated embodiment, shown in Figure 7, the cylindrical body comprises a cylindrical main body 41 and a cylindrical upper body 42. The upper body 42 has a planar upper surface 43 and extends axially and concentrically from an upper surface of the main body, forming an annular shoulder 45 at the upper periphery of the main body 41. The main body 41 has a planar lower surface 44, and a domed cavity 46 formed into the planar lower surface 44 of the main body 41 that consists of the majority of the volume of the irradiation chamber 55, and specifically at least 70% and up to 90% of the volume, and in the illustrated embodiment, about 80% of the volume, of the irradiation chamber 55.

[0093] In some embodiments, a portion of the tangential port 27 can be formed into the lower surface 44 of the chamber body 40, to permit liquid communication between the tangential port 27 of the irradiation chamber 55 and a transfer corridor 39, described in further detail below.

[0094] In the illustrated embodiments, the irradiation chamber 55 is formed when the chamber body 40 is positioned on and secured to the base assembly 20, as illustrated in Figures 5 and 8.Attorney docket: AST-011 -PCT

[0095] The irradiation chamber 55 has a capsule shape or a stadium-of-revolution shape. As shown in Figure 5, irradiation chamber 55 has a dome-shaped lower section, a cylindrical middle section, and an upper hemispherical section, along an axial chamber centerline 102.

[0096] The upper section of the irradiation reactor 55 is formed of an upper wall 49 having a hemi-spherical shape, having an axial centerline 102 that is parallel to and offset from the centerline 101 through the chamber body 40. An upper liquid port 50 in tire upper wall 49 is in fluid communication with the second connection portion 1 1 , and has a centerline coaxial with the centerline 100 of the irradiation chamber 10, though offset from the centerline 102 through the irradiation reactor

[0097] The cylindrical middle section of the irradiation reactor 55 has a cylindrical middle wall 48 and extends to from the lower section to the upper section.

[0098] The dome-shaped lower section of the irradiation reactor 55 has a boundary formed of the lower chamber portion 26 of the base assembly 20 and the quartz window 96.

[0099] The quartz window 96 is positioned in the lower section, disposed along the chamber centerline 102 of the irradiation chamber 55 along the opening 67 through the bottom of the base body 21. The quartz window 96 is positioned within a peripheral seal 95 and fixed inside a window well.

[0100] In some embodiments, a window well 69 comprises a circular cavity within the lower chamber portion 26, for placement of the quartz window 96, and to isolate the irradiation chamber 55 from the electronic housing assembly 80 and its LED (s) 53. In some embodiments, the window well includes a projecting rim along the opening of the lower chamber portion 26 into the window well 69, which frictionally and annularly contacts the peripheral seal 95 surrounding the quartz window 96, so that once the quartz window and peripheral seal are pressed past the projecting rim and into the window well 69, the projecting rim retains and interferes with removal of the quartz window from the window well.

[0101] hr some embodiments, the frictional securement of the quartz window and peripheral seal provide a fluidic seal to prevent the liquid within the irradiation chamber from leaking past the quartz window, and out through the opening 67 in the bottom of the base body 21.

[0102] The radius of the quartz window preferably provides an opening sufficient for the emitted UV radiation that passes through to illuminate the entire inside wall surface of theAttorney docket: AST-011 -PCT irradiation chamber, and namely the surfaces of the lower chamber portion 26, the middle wall 48 and the upper wall 49.

[0103] In another embodiment, a window well for a quartz window in the lower chamber portion of the irradiation reactor is provided by a window plug 57 that retains the quartz window and is secured into the lower chamber portion of the irradiation reactor to fluidly seal irradiation reactor 55 along the quartz window 96. Figures 8-10 illustrate a base assembly 120 having a formed into a lower chamber portion 126 having formed along its axis 102 a threaded window well 169 having a threaded well wall 56 and a lower annular seal surface 166 that surrounds the opening 67 in the bottom of the base body 121. A quartz window 96 is positioned within a cavity formed within the threaded wall 58 and beneath the upper tlange 59b of the window plug 57. The quartz window 96 is disposed within the threaded window well 169, and is sealed at and along its peripheral edge with a peripheral seal 97. The lower annular surface of the peripheral seal 97 can include one or more annular seal rims 98 that are placed into contact with the upper surface of the lower annular seal surface 166. The annular seal rims 98 are placed into a liquid sealing state against the surface of the lower annular seal surface 166 by compressing the window plug 57 downwardly against the upper annular surface of the peripheral seal 97, which compresses the one or more annular seal rims 98 against the lower annular seal surface 166.

[0104] In various embodiments, the window plug 57 includes an upper flange 59b and an outer threaded wall 58. The upper surface of the upper flange 59b forms a portion of the lower chamber portion 126. The outer threaded wall 58 is configured to rotatingly engage the threads of the threaded window well 169, and to press downward on the peripheral seal 97 of the quartz window 96. The compression ensures a leak-proof scaling of the window well when the apparatus is placed into service in a pressurized liquid flow system.

[0105] The window plug 57 also includes a pair of drive ports 59c as a means for securing the window plug 57 to the lower chamber portion 126 of the irradiation reactor 55.

[0106] In some embodiments, the means for securing the window plug 57 is a pair of drive ports 59c formed into opposite sides of the upper surface of the window plug 57, to allow a pair of drive pins of a installation tool to engage the drive ports 59c for rotation. Figures 11 and 12 illustrates an installation tool 15 for installing the window plug 57 into the lower chamber portion of the irradiation reactor. The installation tool 15 has a lower end that includes a cylindrical alignment post 17 that inserts into the upper opening of the window plug 57, above the quartzAttorney docket: AST-011 -PCT window 96, and a pair of oppositely disposed drive pins 18 along the periphery of the installation tool 15, that are configured to enter the drive ports 59c. The installation tool 15 has an upper end having a shaped opening, illustrated as a square opening, for insertion of a driving tool (not shown), such as a square driving bit or an Allen wrench with a square drive end.

[0107] The quartz window 96 is positioned in the window well 169 in the lower chamber portion 126 and secured with the installation tool 15. The quartz window 96 with its peripheral seal 97 are first placed into the low'er cavity of the window' plug 57, and the window' plug 57 is positioned and threaded using the installation tool 15 into the threaded well wall 56. The peripheral seal 97 is compressed against the seal surface 166 that surrounds the opening 67 in the bottom of the base body 121 , fluidically sealing the quartz window within the window well.

[0108] In preferred embodiments, the volume and shape of the irradiation chamber 55 is symmetrical about the chamber centerline 102. In the illustrated embodiment, the lower, middle and upper sections of the irradiation chamber 55 are symmetrical about the chamber centerline 102.

[0109] In other embodiments, the cavity in the chamber body can be formed with other interior surface shapes, such as an ovoid or an ellipsoid.

[0110] In some embodiments, a portion of the tangential port 27 can be formed into the lower surface 44 of the chamber body 40, to permit liquid communication between the tangential port 27 of the irradiation chamber 55 and a transfer corridor 39, described in detail above.

[0111] In various embodiments, the interior surfaces of the irradiation chamber 55 can be coated with a Lambertian scattering material. In other embodiments, the interior surfaces of the irradiation chamber 55 can be coated with a photocatalytic material capable of destroying adsorbed biological materials in the presence of the generated and reflected radiation.<cover body>

[0112] The cover body 60 includes a circular upper w'all 61, an annular, axially-extending first sidew'all 62 extending from a peripheral edge of the circular upper wall 61 , and forming a first cylindrical cavity on the inside of cover body 60. The cover body 60 also includes an annular flange 63 extending radially outward from a distal edge of the first sidew'all 62, and an annular, axially-extending second sidewall 64 extending from a peripheral edge of the annular flange 63, and forming a second cylindrical cavity’ on the inside of cover body 60.Attorney docket: AST-011 -PCT

[0113] The second connection portion 11 extends axially from the circular upper wall 61 along the chamber centerline 101, and having a fluid passage therein extending through and in liquid communication to the upper liquid port 50 in the upper wall 49 of the irradiation chamber.

[0114] In some embodiments, each of the upper wall 61, first sidewall 62, annular flange 63, and second sidewall 64 are disposed concentrically around the axial chamber centerline 101 of the irradiation chamber 10.

[0115] In some embodiments, the upper liquid port 50 of the chamber body 40 is position along the centerline 101 of the chamber 10, and parallel to and offset laterally from the chamber centerline 102 through the irradiation reactor 55.

[0116] To secure the chamber body 40 to the base body 21 , the cover body 60 is placed over the positioned properly positioned and oriented chamber body 40 and threadedly secured to the base body 21 , by engaging the internal threads 65 of the second sidewall 64 of the cover body 60 with the external threads 25 of the sidewall 22 of the base body 21, and rotating until the cover body secured and the irradiation reactor sealed.

[0117] In some embodiments, the upper liquid port 50 passing from the irradiation chamber 55 to the upper surface 43 of the chamber body 40 is placed into liquid communication with the second connection port 12 of the cover body 60. A chamber O-ring 91 is placed within an annular groove in the inner surface of the upper wall 61 of the cover body 60, to seal the passageway to the liquid port 50 in the upper surface 43 of the chamber body 40.

[0118] In some embodiments, an annular ring gasket 92 is placed within the second cylindrical cavity and on and against the internal annular flange 63 of the cover body 60. When the cover body 60 is threaded onto the base body 21, the lower surface of the ring gasket 92 engages and seals against both the upper rim 24 of the base body 21 , and the annular shoulder 45 of the chamber body 40, which seals off the transfer corridor 39.

[0119] In a preferred embodiment, the chamber body 40 is “keyed” in only one position rotationally along the chamber centerline 101 relative to the base body 21. This means that the base body 21 is configured to be engaged to the chamber body 40 in only one axial rotational position, whereby certain elements of the chamber body 40 only properly engage and align with corresponding elements of the base body 21 in the one rotational position. As illustrated in Figure 7, the lower half 27a of a tangential port 27 and the chamber lower wall rim 28 of the base body 21 can only align axially with, for properly engaging, the corresponding upper half 51 of the liquidAttorney docket: AST-011 -PCT tangential port and the irradiation chamber lower flange 47 of the base body 21 , if the chamber body 40 is in the one proper, rotational position relative to the base body 21.<UV irradiation source>

[0120] In various embodiments, the irradiation assembly can include a monitoring / detection mechanism and control circuitry for dynamically controlling the delivery of UV radiation to the material to be irradiated based on flow rate, water quality, user input, or other operating conditions. Finally, associated performance data may be stored in an onboard or external data storage unit.

[0121] In various embodiments, the UV LED can be a UV radiation source package containing a single LED or multiple LED "dice" arranged in a matrix or array. The LED dice can be selected to provide multiple wavelengths in both the U V and visible radiation spectrum from about 200 nm to about 800 nm. In one exemplary embodiment, the matrix or array includes LED dice emitting wavelengths in the range of about 200-320 nm to saturate the absorption mechanism of nucleocapsids (with peak emission centered at around 280 nm), and at the same time to target the peak absorption of nucleic acid with its peak emission wavelength spanning about 250-280 nm. In another exemplary embodiment, with the intention of mimicking the optical output spectrum of low or medium pressure Hg-based LJV lamps used to target various bacteria and viruses, the matrix or array of LED dice utilizes multiple wavelengths, including at least one of about 240-260 nm, about 260-344 nm, about 350-380 nm, about 400-450 nm, or about 500-600 nm. A further exemplary embodiment is a matrix or array of LED dice emitting germicidal wavelengths ranging from about 250 nm to 300 nm in conjunction with LED dice emitting wavelengths in the range of about 350 nm to 400 nm to enable photocatalytic oxidation of pathogens or pollutants in water in proximity of crystalline films of n-type semiconductors, such as TiO2, NiO, or SnO2. A still further exemplary embodiment is a modular mounting configuration containing multiple LED dice emitting about 250-320 nm and about 320-400 nm wavelengths arranged in a matrix or array to enable the fluorescence spectra of NADH, and tryptophan, of particles with biological origin. In another exemplary' embodiment, a commercially available SETi UV Clean™ LED package is used. Individual LED dice or a single die bonded to a thermally conductive metal core circuit board (MCPCB), such as those available from The Bergquist Company™, may also be used.

[0122] hr various embodiments, the LED package may be electrically connected to control and power circuitry', which is included as part of the replaceable module. Circuitry is included withinAttorney docket: AST-011 -PCT the replaceable module to provide telemetric data and track information, such as operating temperature and run time.

[0123] Components for the electrical and / or electronic control of the UV radiation source may optionally be included within the sealed electronics housing assembly 80, such that they may act upon the UV radiation source whilst maintaining protection from the external environment through such hermiticity, the use of desiccants, or a combination thereof. Further, the co-location of these components onto the MCPCB, or otherwise, and subsequent thermal union to the heat exchange mechanism may be used to extract heat generated by, for example, power conversion components. Additionally, these electrical and / or electronic components may include sensors by which the operating conditions and status of the UV radiation source may be determined, including but not limited to a photodiode, thermocouple, thermistor, acoustic sensor, hall probe, current probe, etc. A power and control junction box 93 extends through the electronic housing base 87 and delivers power and control wiring to the electronic components and LED(s) 53 positioned on the PCB board 52.

Claims

Attorney docket: AST-011 -PCTWe claim:

1. An irradiation apparatus comprising: an interior irradiation reactor, a first liquid port and a second liquid port for liquid flow into and out of the irradiation reactor; a UV radiation source configure to emit UV light through an opening in a lower wall of the irradiation chamber, the UV radiation source having a heat-emitting surface; and a first connection port for connection to either a liquid supply source or a liquid usage device, the first connection port consisting of a metal tubing comprising an outer sidewall, a portion of the outer sidewall comprising a thermal contact surface disposed in confronting contact with the heat-emitting surface of the UV radiation source, thereby providing a heatsink for the UV radiation source.

2. The irradiation apparatus according to Claim 1, wherein the metal tubing is copper tubing.

3. The irradiation apparatus according to either Claim 1 or Claim 2, wherein the thermal contact surface of the metal tubing is in direct thermal contact with the heat-emitting surface.

4. The irradiation apparatus according to any one of Claims 1-3, wherein a thermal interface material is placed between the thermal contact surface and the heat-emitting surface.

5. The irradiation apparatus according to any one of Claims 1-4, wherein the ratio of the lateral width of the thermal contact surface to the outer diameter of the metal tubing is about 0.6 to 0.9:1, and preferably about 0.78 to 0.82.

6. The irradiation apparatus according to any one of Claims 1-5, wherein a ratio of a radial distance from a centerline of the metal tubing, of the thermal contact surface to the outer surface of the metal tubing, is 0.55-0.85: 1, and preferably about 0.65-0.70: 1.

7. The irradiation apparatus according to any one of Claims 1-6, wherein the metal tubing includes a distal transfer segment having a transverse opening formed through the cylindrical wall perpendicular to an axial centerline of the distal transfer segment, for placing the metal tubing in liquid communication with the irradiation reactor.Attorney docket: AST-011 -PCT8. The irradiation apparatus according to Claim 7, wherein the transverse opening is a circular bore having a diameter of about 75-100% of, and preferably the same as, an inside diameter of the distal transfer segment.

9. The irradiation apparatus according to any one of Claims 1-8, wherein the irradiation chamber has a capsule shape.

10. The irradiation apparatus according to any one of Claims 1-9, wherein the first liquid port is disposed in the lower wall of the irradiation chamber, and the second liquid port is disposed in an upper wall of the irradiation reactor.

11. The irradiation apparatus according to any one of Claims 1-9, wherein the first liquid port is oriented along a flow path tangential from the axial centerline of the irradiation reactor.

12. The irradiation apparatus according to any one of Claims 1-11, wherein the apparatus includes an irradiation chamber consisting of: i) a base body that includes a lower portion of the irradiation reactor, a means for positioning a quartz window in the lower portion of the irradiation reactor, at least a portion of the first liquid port, and a transfer port for placing the first connection port in liquid communication with the first liquid port of the irradiation reactor, ii) a chamber body that has a cavity that consists of a remaining portion of the irradiation reactor and the second liquid port, and iii) optionally a cover body that includes the second connection port positioned to place the second connection port in liquid communication with the second liquid port.

13. The irradiation apparatus according to Claim 12 wherein the base body is configured to be engaged to the chamber body in only one axial rotational position.

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