Drain water heat recovery device, system and method

Abstract

Various devices, systems and methods affiliated with thermal recovery using heat transfer are disclosed. More specifically, the device and systems are directed to heat recovery device and systems for enhancing thermal energy transmission between two fluids. More particularly, the recovery of energy from heated fluid including drain water from appliances. The heat recovery device includes a plurality of layers: a first layer configured as an internal conduit for a first fluid flow; a second layer on the internal conduit; and an insulating jacket housing with a helical cut pathway for a second fluid flow. The device includes a thermal exchange surface, couplings / caps, attachments and support elements. The device and systems include the thermal exchange surface including copper and copper / graphene mixtures for enhanced thermal exchange and recovery.

Description

DRAIN WATER HEAT RECOVERY DEVICE, SYSTEM AND METHODInventors: Hany F. Koelling, Bryan F. Koelling, and Peter J. RileyCROSS-REFERENCE TO RELATED APPLICATION

[0001] This Application claims the benefit of priority under 35 U.S.C. §1 19(e) based on U.S. Provisional Patent Application having Application No. 63 / 564,419 filed on March 12, 2024, and entitled “Drain Water Heat Recovery Device, System and Method”, which is hereby incorporated herein by reference in its entirety.FIELD OF THE INVENTION

[0002] The present invention relates to energy conservation devices, systems and methods using heat transfer. More particularly, the invention relates to the recovery of energy from heated water from appliances, particularly energy recovery from heated water / drain water from home appliances including dishwashers and washing machines along with heated water used in showers, bathtubs, and kitchen and bathroom sinks.BACKGROUND OF THE INVENTION

[0003] Conventional drain water heat recovery devices have been in use to recover heat from hot water drain sources (grey water) in the home / buildings. However, current devices only have efficiencies at or below 40% and require high use of copper metal, which adds to the cost and weight of such devices. For example, a current drain water heat recovery device includes a copper drainpipe (internal conduit or internal pipe) having a diameter to match the size of the plumbing stack it replaces,and a smaller diameter copper tube that is tightly wound around the inner pipe ( i.e., the copper inner pipe is surrounded by a coiled copper tube). Typically, drain water goes down the inner pipe while potable water is circulated within the coiled copper tube surrounding the inner pipe to recover heat from the drain water. However, such designs come with the disadvantages in being less than ideal in its contact area between counterflowing stream, are heavy, costly, and prone to theft.

[0004] There is a need for significant improvement in thermal energy recovery by applying methods for improved thermal conduction between two opposed flowing fluids (potable stream versus non potable water flow). At the same time, products in this category must meet the efficiency measurement standards and construction basics as established for example in CSA B55.1:20, revision October 2021 document (hereby incorporated by reference in its entirety).

[0005] Therefore, it would be advantageous to have a solution that utilizes improved methods and materials and construction geometry to accomplish the purposes of increased thermal transfer efficiency and reduction in costs thereby providing an improved cost / savings benefit to purchasers.SUMMARY OF THE INVENTION

[0006] The present invention is directed to an improved drain water heat recovery device, system and methods for heat recovery, designed to improve energy recovery from hot water drain sources compared to existing products.

[0007] In a typical embodiment of the present invention, a thermal recovery device to enhance thermal energy transmission between two fluids is provided. Typically, the device comprises a plurality of layers: 1) a first inner layer configured to surround and transport a first fluid, the first fluid capable of giving off heat; 2) asecond outer layer deposited on to an outer surface of the first inner layer; and, 3) a third insulating layer surrounding the second outer layer, the third insulating comprising a helical cut pathway into an interior surface of the third insulating layer; the helical cut pathway, configured to transport a second fluid.

[0008] In one embodiment, the first inner layer and second outer layer together forming a thermal exchange layer surface to enhance thermal transmission.Preferably, the innermost diameter of the third insulating layer is flush and matches an exterior surface diameter of the second outer layer. More preferably, the second fluid is circulated within the helical cut pathway and exposed to the second outer layer to receive thermal energy from the first fluid.

[0009] According to a preferred embodiment of the present invention, the drain water heat recovery device comprises a non-potable internal drainage pipe / conduit surrounded by a jacket housing having a helical cut pathway through which the counterflow potable water flows in and out via piping / hose connections. Preferably, the internal drainage pipe is a single internal copper pipe configuration with an outer copper layer, wherein the outer copper layer has a thickness less than the thickness of the internal copper pipe; and the jacket housing which conceals the internal pipe is made of PVC material. An end coupling / cap is positioned at each end of the device and a corresponding “O” ring is provided at each end connecting the jacket housing to the internal drainage pipe and to the end coupling / cap. The device further comprises of two-end caps at each end to ensure integrity of the seal provided by each “O” ring and a drainage connector at each end for connecting the device to the existing drain pipe / plumbing stack.

[0010] According to an embodiment of the present invention, a method for heat recovery between non-potable water and potable water using a heat recovery devicecomprises: guiding non-potable water through an inside of a conduit for the device, the non-potable water received at a first end of the conduit and discharged through a second end of the conduit; receiving potable water at an inlet end of a helically cut channel of a jacket housing surrounding the conduit, wherein the inlet end is at an opposite end from the first end of the conduit; circulating the potable water through the helically cut channel, the circulating potable water having direct contact with an exterior surface of the conduit; transferring thermal energy from the inside of the conduit to the exterior surface; heating the potable water from the contact with the exterior surface; and emitting the potable water at an outlet end of the helically cut channel of the jacket housing.

[0011] According to embodiments of the present invention, the device employs manufacturing methods that enhance surface area and water flow retention rates. To comply with CSA B55.1 :20 standards, the device comprises a clear PVC end cap for connection to drain pipes, allowing visual inspection for leaks between grey and potable water flows. Additionally, the device reduces the amount of copper required as a thermal transfer medium and conceals copper within a PVC outer jacket to deter theft.

[0012] The device of the present invention provides significant improvements in drain water heat recovery by increasing thermal efficiency to high 50% efficiency. |0013| These features, advantages and other embodiments of the present invention are further made apparent in the remainder of the present description and drawings, to those of ordinary skill in the art.BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to describe embodiments of the present invention more fully, reference is made to the accompanying drawings. These drawings are not to be considered limitations in the scope of the invention, but are merely illustrative.

[0015] FIG. 1A illustrates a schematic front view of the fully assembled heat recovery device according to an embodiment of the present invention.

[0016] FIG. IB is a cross-sectional side view taken along and in the direction of the line [A-A] in FIG. 1A.

[0017] FIG. 1C illustrates another schematic view of FIG. 1A rotated partially in the axial direction and with the collar position adjusted.

[0018] FIG. ID illustrates a schematic view of FIG. 1C detailing the inlet and outlet connections for both the potable and non-potable flow of water including the internal view of the jacket for the potable water which surrounds the internal non- potable (drainage) pipe of the device, according to an embodiment of the present invention.

[0019] FIG. 2A illustrates an exploded perspective view of one end of the heat recovery device, according to an embodiment of the present invention.

[0020] FIG. 2B illustrates an alternative enlarged partial cross-sectional view of one end of the heat recovery device, according to an embodiment of the present invention.

[0021] FIG. 3 shows an enlarged perspective partial end view of the non-potable drainage pipe of the heat recovery device according to an embodiment of the present invention.

[0022] FIG. 4 illustrates another cross-sectional view of the device showing the jacket housing which surrounds the non-potable pipe of the device, according to an embodiment of the present invention.

[0023] FIG. 5A illustrates an enlarged partial cross-sectional side view of one end of the device shown in FIG. IB, according to an embodiment of the present invention.

[0024] FIG. SB illustrates an enlarged partial sectional outline view of one end of the device taken along a cut line through an inlet / outlet portal, according to an embodiment of the present invention.

[0025] FIG. SC illustrates a partial schematic view of an assembled heat recovery device according to an embodiment of the present invention.

[0026] FIG. 5D is a cross-sectional side view taken along and in the direction of the line [B-B] in FIG. SC showing the device without the non-potable drainage pipe (inner conduit).

[0027] FIGS. 6A - 6B illustrate a perspective view and a side view of an end coupling with threaded inlet / outlet of the heat recovery device according to an embodiment of the present invention.

[0028] FIGS. 7A - 7B illustrate a perspective view and a side view of an end cap of the heat recovery device according to an embodiment of the present invention.|0029| FIGS. 8A - 8B illustrate a plan view and a side view of an “O” ring of the heat recovery device according to an embodiment of the present invention.

[0030] FIGS. 9A - 9B illustrate a perspective view and a side view of a drainage connector, for connecting the heat recovery device to a drain pipe, according to an embodiment of the present invention.

[0031] FIGS. 10A - 10B illustrate a perspective view and a side view of a hose coupling (inlet / outlet connection) of the heat recovery device, according to an embodiment of the present invention.

[0032] FIGS. 11A - 11B illustrate a perspective view and a plan view of a snap on I snap off removable circular attachment having a round spirit level located on a widened protruding area on the side of the ring of the heat recovery device, according to an embodiment of the present invention.

[0033] These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description.DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

[0034] The description and the drawings of the present disclosure focus on one or more preferred embodiments of the present invention, and describe exemplary optional features and / or alternative embodiments of the present invention. The description and drawings are for the purpose of illustration and not limitation. Those of ordinary skill in the art would recognize variations, modifications and alternatives which are also within the scope of the invention.

[0035] Various embodiments of the present invention illustrated in the drawings may not be drawn to scale. Rather, the dimensions of the various features may be expanded or reduced for clarity. In addition, some of the drawings may be simplified for clarity. Thus, the drawings may not depict all of the components of a given apparatus (e.g., device) or method. The same reference indicators will be used throughout the drawings and the following detailed description to refer to the same or like parts.

[0036] The present invention addresses the aforementioned need for a thermal recovery device. More specifically, various embodiments of a heat recovery device, systems and methods are disclosed.

[0037] In an embodiment of the present invention, a thermal recovery device designed to recover thermal energy (for example, heat) from a fluid and transfer thermal energy to another fluid is presented. In a most preferred embodiment of the present invention, the thermal recovery device is a heat recovery device designed to enhance thermal energy transmission between a first fluid and a second fluid. Preferably, the heat recovery device includes a plurality of layers; a first inner layer configured to transport the first fluid; a second outer layer deposited on the first inner layer; and, a third insulating layer surrounding the second outer layer deposited on the first inner layer; the third insulating layer comprising a helical cut pathway into an interior surface of the third insulating layer; the helical cut pathway capable of transporting the second fluid. Preferably, the second fluid is circulated within the helical cut pathway and exposed to the second outer layer deposited on the first layer to receive thermal energy from the first fluid.

[0038] In a typical embodiment of the present invention, the first inner layer and the second outer layer comprise a metal composite mixture.

[0039] According to a typical embodiment of the present invention, the heat recovery device includes the plurality of layers arranged in a cylindrical tubular concentric sequence. Generally, in a typical embodiment, the plurality of layers is configured into a plurality of open ended elongated concentric conduits, pipes, tubes, or channels, capable of holding, containing, receiving, guiding and transporting fluids between the layers. Preferably, the thermal recovery device includes concentric conduits, pipes or tubes with a circular cross section to ensure even efficient transferof thermal energy between the two fluids, however it can be understood that any shape, (for example, oval, elliptical, rectangular, square) can be used according to preference.

[0040] Preferably, the first inner layer is a cylindrical core configured to transport the first fluid. Preferably, the second outer layer is deposited on the first inner layer forming a thermal exchange surface. More preferably, the third insulating layer has an inner diameter matching the outer diameter of the second outer layer deposited on the first inner layer, wherein the combination of the helical cut pathway against the outer diameter of the second outer layer forms a conduit for the second fluid.

[0041] In a typical embodiment of the present invention, the first fluid is capable of giving off thermal energy and the second fluid is capable of receiving thermal energy given off by the first fluid.

[0042] In a most preferred embodiment of the present invention, the second outer layer has a thickness less than the thickness of the first inner layer.

[0043] In a preferred embodiment of the present invention, the thermal recovery device comprises 1) a drainage pipe comprising: the second outer layer deposited on the first inner layer; and 2) the third insulating layer with the helical cut pathway.

[0044] In a typical embodiment, the first inner layer is a core layer and can be configured into a conduit, pipe, hollow tube, or channel capable of holding, transporting and circulating the first fluid. The first inner layer configured to transport a first fluid may be referred to as an internal conduit of internal pipe. The third insulating layer configured to transport a second fluid be referred to as an insulating jacket housing.

[0045] In a most preferred embodiment of the present invention, the thermal recovery device comprises 1) a drainage pipe comprising: the second outer layerdeposited on the internal conduit or internal pipe; and 2) a jacket housing comprising the third insulating layer with the helical cut pathway. Preferably, the helical cut pathway is cut into the interior surface of the jacket housing.

[0046] In yet another embodiment of the present invention, the first inner layer comprises any conductive material known to those skilled in the art that allows thermal transfer efficiency. Typically, the first inner layer comprises a metal composite mixture material which can include but not be limited to aluminum, brass, cadmium, copper, graphene, nickel, steel, stainless steel, zinc, and mixtures thereof. Preferably, the first inner layer comprises a copper composite mixture with copper / graphene. More preferably, the first inner layer comprises a copper mixture with about 99.5% copper.

[0047] In a preferred embodiment of the present invention, both the first inner layer and the second outer layer comprise at least 99.5% copper minimum with the remainder of 0.5% including typical “impurities” or minority metals known to those skilled in the art, for example, metals, alloys, elements etc., in compliance with NSF61 / ANSI / CAN 600:2023 standards which is included herein in its entirety (for example, the balance of the minority metals and their maximum concentration are provided within). It can be appreciated by those skilled in the art that the code referenced within the aforementioned reference protects potable water streams from leaching, and possibly accumulating any undesirable metals for human consumption. In still yet another embodiment, the 0.5% minority metals can include phosphorous at about 0.025% and other small amounts of about 20 other metals known to those skilled in the art.

[0048] In yet another alternate embodiment of the present invention, the first inner layer comprises a metal composite mixture made of a copper / graphene mixture.Preferably, it can be appreciated by those skilled in the art that the higher the percentage of graphene, the greater the thermal conductivity. In a most preferred embodiment, the copper / graphene mixture can be from 8% copper and 92% graphene. According to an embodiment, a minimum copper composition from about 8% is needed to best align single molecular layer graphene deposits.

[0049] In yet still another embodiment of the present invention, the second outer layer comprises any metal composite mixture known to those skilled in the art that can allow thermal transfer efficiency. Typically, the metal composite mixture can include but not limited to aluminum, brass, cadmium, copper, graphene, nickel, steel, stainless steel, zinc, and mixtures thereof. Preferably, the second outer layer comprises a copper composite mixture with about 99.5% copper in compliance with NSF61 / ANSI / CAN 600:2023 standards. Similarly, the remainder of 0.5% including typical “impurities” known to those skilled in the art, for example, metals, alloys, elements etc.

[0050] In yet still another preferred embodiment of the present invention, the second outer layer comprises a copper / graphene mixture. Preferably, it can be appreciated by those skilled in the art that the higher the percentage of graphene, the greater the thermal conductivity. In a most preferred embodiment, the copper / graphene mixture can be from 8% copper and 92% graphene. According to an embodiment, a minimum copper composition from about 8% is needed to best align single molecular layer graphene deposits.

[0051] In a most preferred embodiment of the present invention, the first inner layer is configured as an internal conduit or internal pipe made of 99.5% copper.

[0052] In another embodiment of the present invention, the second outer layer comprises 99.5% copper deposited on the internal conduit. In another embodiment,the second outer layer is an outer second copper mixture layer, deposited on the internal conduit. Preferably the outer second copper mixture layer is made of 99.5% copper. In another embodiment, the outer second copper mixture layer is an outer second copper / graphene mixture layer.

[0053] In a typical embodiment, copper layers are preferred since copper is known to be used in plumbing and pipes for potable / non-potable systems. Graphene is known to those skilled in the art to be one of the most conductive materials for conducting heat and electricity. In a most preferred embodiment, a copper / graphene mixture for the first inner layer and / or second outer layer would ensure a thermal exchange surface with enhanced heat transmission and recovery.

[0054] In yet another embodiment of the present invention, the first inner layer and the second outer layer deposited on to the first inner layer are conformed together and can be referred to hereinafter as a “unit”. In one embodiment, the “unit” can include the drainage pipe comprising the second outer layer deposited on the first inner layer and can be used interchangeably.

[0055] Preferably, the third insulating layer is a jacket housing with an inner diameter matching the outer diameter of the “unit”, for containing the second fluid flow to remain in the helical cut pathway, thus preventing the second fluid (potable water) from bypassing the helical path taken by the second fluid (cold potable water) flow.

[0056] Preferably, the second fluid is exposed to and in contact with an exterior surface of the “unit” and the interior surface of the helical cut pathway or helical groove contained in the jacket housing, wherein the combination of the pathway surface against the exterior surface of the “unit” creates a helical conduit for the second fluid.

[0057] In yet another embodiment of the present invention, the second outer layer is aligned and deposited on to the first inner layer to provide optimized surface contact geometry by increasing and enhancing the outer surface area of the second outer layer, to allow for maximum thermal transfer efficiency between the first fluid and the second fluid and water flow retention rates.

[0058] In a typical embodiment of the present invention, the jacket housing of the heat recovery device is configured to surround, encase and conceal a sufficient area of the drainage pipe to ensure maximum thermal transfer efficiency by recovering heat from the first fluid and transferring heat to the second fluid.

[0059] In yet a most preferred embodiment, the jacket housing comprises the third insulating layer and can be a rigid cylindrical hollow shell molded around and surrounding the second outer layer deposited on to the first inner layer. Preferably, the jacket housing is a thermal insulating jacket housing to retain thermal recovery. In yet still another embodiment of the present invention, the jacket housing includes but is not limited to any thermal insulating material known to those skilled in the art including plastic, composite, metal or mixtures thereof. Preferably, the jacket housing is made of any plastic, rubber, metal or composite material known to those skilled in the art. Preferably, the third insulating layer or jacket housing is a plastic. More preferably, the third insulating layer or jacket housing is PVC.|0060| In yet another preferred embodiment of the present invention, the third insulating layer or jacket housing is composed of PVC and provides a thermal insulation R-value range of 11.2-12.6.

[0061] In yet a preferred embodiment, the j acket housing containing the helical cut pathway on to the interior surface of the jacket housing is flush with the second outer layer, configured to contain and form a helical groove conduit to hold the flowof the second fluid. Preferably, the jacket housing has an inner diameter, formed by the inner facing channel edges of the helical pathway, that is flush against and matching the outer diameter of the “unit” (internal conduit and outer layer), preventing the second fluid potable water from by passing the helical path taken by the cold potable water flow. In a most preferred embodiment, the jacket housing containing the helical cut pathway is flush with the exterior surface of the second outer layer, and is configured to form a helical groove conduit or channel to transport a second fluid.

[0062] In an embodiment of the present invention, the exterior surface of the second outer layer is configured to align with an interior surface of the jacket housing containing the helical cut pathway such that the second fluid flowing through the helical cut pathway is exposed to the exterior surface of the second outer layer deposited on the first inner layer to allow maximum thermal energy transmission.

[0063] In yet a most exemplary preferred embodiment of the present invention, the inner diameter interior surface of the jacket housing is machine cut with a rectangular helical cut pathway containing the second fluid (for example, cold potable water) such that the second fluid circulates continuously around the exterior thermal surface of the second outer layer deposited on first inner layer; thus increasing cold water retention time while causing only minimal pressure drop (1 or 2 psi). This design enhances thermal heat exchange efficiency. Typically, the jacket housing insulates the second fluid (for example, potable water) flow and prevents thermal loss to the atmosphere.

[0064] In yet still another embodiment of the present invention, a majority of the first inner layer or internal conduit, and second outer layer are concealed within the jacket housing, thus reducing the visibility of the copper and deter the potential oftheft. Preferably, the jacket housing with the inner helical cut pathway designed potable water passage-ways obtain maximum efficiency when the total amount of contact surface area approaches or reaches 100%.

[0065] In a preferred embodiment of the present invention, the first fluid is of greater temperature (for example, hotter) than the second fluid (cold).

[0066] In an embodiment of the present invention, the first fluid can be any fluid known to those skilled in the art that can give off thermal energy including and not limited to liquids, gas or any mixtures thereof. Typically, the first fluid can include for example, water; coolant; oil; radiator fluids; etc.

[0067] In yet another embodiment of the present invention, the second fluid can be any fluid known to those skilled in the art that can receive thermal energy including and not limited to liquids, gas or any mixtures thereof. Typically, the second fluid to receive thermal energy can include for example, water; coolant; oil; radiator fluids; etc.

[0068] Preferably, the first fluid is non-potable grey water or grey drain water and the second fluid is potable drinking water. More preferably, the non-potable grey water or grey drain water is hot and the potable drinking water is cold. In a most preferred embodiment of the present invention, the first inner layer is an internal drainage pipe containing the first fluid such as non-potable water or grey -drain water. |0069| In yet another preferred embodiment of the present invention, the interior surface of the first inner layer or internal conduit or internal pipe can further include at least one coating. The coating can be any coating known to those skilled in that art and preferably includes at least one super hydrophilic, oleophobic and mixtures thereof. Preferably, the coating is used to 1) enhance hot first fluid film formation on the interior surface of the first inner layer or internal conduit or internal drainage pipe,to prevent buildup of oil or other contaminants, and enhance flow of fluid and ensure efficient and maximum thermal energy transfer.

[0070] According to embodiments of the present invention, super hydrophilic / oleophobic coating / film(s) include but are not limited to TiCh (Titanium dioxide), S1O2 (Silica dioxide), GO (Graphene Dioxide), polyvinyl alcohol (PVA), chitosan (CTS), glutaraldehyde (GA) with TiOz (Titanium oxide) nanoparticles and plasma films using oxygen or ammonia to increase wettability and create a super hydrophilic / oleophobic coating surface.

[0071] In yet still another embodiment of the present invention, methods for applying the coating(s) including super hydrophilic / oleophobic film(s) are disclosed. Depending on the super hydrophilic / oleophobic film(s) applied, methods for the application include but are not limited to plasma formation, sol-gel deposition, spin coating, dip coating or spray coating or any other methods known to those skilled in the art.

[0072] In yet another typical embodiment of the present invention, the thermal recovery device (for example, heat recovery device) can further include attachments to connect or couple, seal and cap. In an embodiment of the present invention, attachments such as couplings are provided to couple or connect the plurality of layers of the device, or the drainage pipe with the jacket housing of the thermal recovery device. In yet still another embodiment of the present invention, connectors are provided to connect the thermal recovery device to external fluid sources. Preferably, these connectors can supply / drain fluids undergoing thermal transmission. In a most preferred embodiment of the present invention, the thermal recovery device includes coupling(s), “O” ring(s), end cap(s) and connector(s) for each end of the device. In an embodiment of the present invention, the attachments to connect, couple, seal and capcan be any connecting or fastening mechanism known to those skilled in the art, including but not limited to mechanical (for example, screws, bolts, chemical, welding, etc.).

[0073] In an exemplary embodiment of the present invention, preferably, the two fluids (the first fluid and the second fluid) undergoing thermal exchange, are never in direct contact with each other. More preferably, within the thermal recovery device, although the first fluid and second fluid can flow in a parallel directions, e.g. and / or substantially in the direction of gravity, in a most preferred embodiment, the first and second fluids are in a counterflow stream direction with each other.

[0074] In a typical embodiment of the present invention, the coupling is configured to seamlessly match the first inner layer or internal conduit, and second outer layer to prevent disruption of the first fluid flowing down the interior surface of internal conduit . When assembled, one side of the end coupling abuts the terminal end of the internal conduit or internal pipe and the second outer layer, and is surrounded by the “O” ring.

[0075] According to an embodiment of the present invention, each of the coupling(s) include an inlet / outlet portal(s) at each end of the thermal recovery device; the inlet(s) configured to supply and receive the entry of the second fluid, and the outlet(s) configured to transfer and exit the (heated) second fluid for use in a heat recovery system.

[0076] Preferably, each of the coupling(s) of the thermal recovery device are configured to ensure the first fluid and second fluid streams are never in direct contact with each other. Each of the coupling(s) are aligned to the “unit” and jacket housing and configured such that the first fluid flows in one path in one direction within the interior surface of the coupling pair attached to the end of the “unit”; and the secondfluid flows on another path in another direction within the helical cut pathway within the jacket housing on the exterior of the “unit” with no direct contact between the fluids.

[0077] In a most preferred embodiment of the present invention, the inlet / outlet portals are configured and designed to induce turbulent centrifugal movement of the second fluid (for example, potable water) through the helix cut pathway of channels in the interior surface of the jacket housing (preferably made of PVC), enhancing thermal transfer efficiency by increasing the second fluid’s (for example, potable water) surface are and interaction time with the thermal exchange surfaces provided by the “unit” (second outer layer deposited on the first inner layer) both layers made preferably of a copper composite mixture.

[0078] In still yet another embodiment of the present invention, each of the coupling(s) are capable of connecting the jacket housing to the “unit” or drainage pipe, allowing the first fluid to counterflow along the interior surface of both the “unit” or drainage pipe. Preferably, the coupling can be made of the same insulating material as the jacket housing and can include but is not limited to any thermal insulating material known to those skilled in the art including plastic, composite, metal or mixtures thereof. Preferably, the coupling(s) are made of any plastic, rubber, metal or composite material known to those skilled in the art. According to the most preferred embodiment of the present invention, the end coupling preferably is comprised of a clear PVC.

[0079] Preferably, each coupling(s) can include holes, and can be secured via any securing means known to those skilled in the art including mechanical, chemical, welding, etc. Preferably, the end caps are secured to the coupling(s) via a mechanical mechanism and are attached and secured by metal screws or bolts.

[0080] In a most preferred embodiment of the present invention, the “unit” is surrounded by the jacket housing having a helical cut pathway through which the second fluid counterflows in and out via inlet / outlet connections located on each end coupling. Preferably, the inlet / outlet connections are connected to an external piping / hose to supply, circulate and drain the second fluid. More preferably, each of the coupling(s) are also aligned to connect the interior surface of the jacket housing to the interior surface of the “unit” or drainage pipe, allowing the first fluid to counterflow against the second fluid; the “unit” capable of sufficiently supplying a thermal enhancement layer(s) or surface to exchange thermal energy between the first fluid and the second fluid with enhanced and maximum efficiency.

[0081] In a most preferred embodiment of the present invention, the first fluid flows along the interior surface of both the “unit” or drainage pipe while the second fluid circulates in a counter flow direction on the exterior surface of both the “unit” or drainage pipe (within the helical cut pathway on the interior surface of the jacket housing); wherein the “unit” (first inner layer with the second outer layer deposited on the first inner layer). In a most preferred embodiment, the first fluid is non-potable water and the second fluid is potable water.

[0082] In yet still another embodiment of the present invention, corresponding “O” ring(s) are provided and are positioned at each end of the thermal recovery device between the coupling(s) and end cap(s). Preferably, the “O” ring(s) provides a tight seal by isolating the “unit” (second outer layer deposited on the first inner layer) from the jacket housing and connects the end coupling. In a typical embodiment the “O” ring is configured to maintain inner second fluid inlet pressure without allowing leakage from the jacket housing. In yet another embodiment, the “O” ring connects the jacket housing to the internal conduit and second outer layer and the second fluidoutlet coupling. In a most preferred embodiment, the precision fit and material integrity of the “O” ring ensure no leakage between opposing first and second fluid flows. Typically, the “O” ring can be made of silicon, rubber, plastic or any composite material known to those skilled in the art known to ensure a seal.

[0083] In another typical embodiment of the present invention, the thermal recovery device can further include end cap / connector(s) positioned at each end of the device and is placed over the “O” ring to secure and compress the circular “O” ring to retain the second fluid flow within the helical cut pathway of the jacket housing under normal operating water pressure, contain the “unit” and jacket housing. End cap / connector(s) can referred herein as “end cap” and understood to function as both an end cap and a connector. Typically, the end cap(s) ensure the flow of the second fluid to be redirected through the inlet / outlet connectors on each of the coupling(s); yet provides a connection for the flow of the first fluid within the interior surface of the interna] conduit to external fluid supply / drain source. In a most preferred embodiment, the end cap(s) are made of any plastic, rubber, metal or composite material known to those skilled in the art. Preferably, the end cap(s) is a plastic such as PVC. More preferably, the end cap is made of clear PVC.

[0084] Use of a clear PVC coupling(s) and end cap / connector(s) are designed to allow visual inspection for potential leaks between the inner first layer and outer second layer, or the “unit” with the jacket housing providing efficient leak detection and maintenance.

[0085] Preferably, each end cap can include holes, and can be secured to the coupling(s) via any securing means known to those skilled in the art including mechanical, chemical, welding, etc. Preferably, the end caps are secured to thecoupling(s) via a mechanical mechanism and are attached and secured by metal screws or bolts.

[0086] The thermal recovery device of the present invention can further include drainage connector(s) at each end of the thermal recovery device to provide supply and drain channels for the first fluid (for example, non-potable water) from an existing drain pipe / plumbing stack. The drainage connectors can include any drain connectors known to those skilled in the art. In an embodiment, the drainage connector(s) for the drain pipe / plumbing stack to the thermal recovery device, can include an internal rubber compression seal and stainless-steel hose clamps for a watertight joint with the end cap(s).

[0087] Preferably, the first fluid is a warm or hot fluid to provide thermal energy (such as heat) to be transferred to the second fluid. In a most preferred embodiment, the path flow of the second fluid from the jacket housing inlet to the outgoing path jacket housing outlet is countercurrent to the flow of the first fluid counterflowing from within the interior surface of the “unit”.

[0088] Preferably the jacket housing of the thermal recovery device prevents thermal loss to the atmosphere and is designed to control the second fluid flow to increase contact area and residence time between the first fluid and the second fluid counterflowing streams and thereby improves thermal transfer. Moreover, the device and methods allows for maximizing retention time of potable water flow to facilitate heatenergy transfer without causing any significant drop in water pressure.

[0089] In yet another embodiment of the present invention, the thermal recovery device is connected to an external fluid source to provide the fluids involved in heat recovery process. The external fluid source can be for example, a water pump, water heat, radiator, etc.

[0090] In yet another embodiment of the present invention, heat recovery system(s) are provided using the aforementioned heat recovery device described above. In one particular embodiment, a heat recovery system with a PVC potable water layer from the heat recovery device is provided. Preferably, the heat recovery water system includes the heat recovery device with insulating third outer layer. More preferably, the insulating third outer layer is a jacket housing comprising PVC. In a most preferred embodiment, the insulating third outer layer has a thermal insulation R-value range from about 11.2 to about 12.6. The thermal insulating layer or jacket housing preferably provides the heat recovery device and system with reduced heat loss to the external environment. Additionally, the system provides exemplary cost savings compared to other existing systems, by utilizing copper composite mixtures for the first inner layer and second outer layer of the heat recovery device surrounded by the insulating third outer layer or jacket housing made of PVC with the thermal insulation R-value from about 1 1.2 - 12.6.

[0091] In yet another particular embodiment, a heat recovery system with the aforementioned heat recovery device with copper / graphene layers is provided. Preferably, the heat recovery system includes the heat recovery device with the first inner layer and the second outer layer are copper composite mixtures. More preferably, the first inner layer and the second outer layer are made of a copper / graphene composite mixture material. Copper / graphene composite material is known to provide a 5x to 8x increase in thermal transfer efficiency compared to copper alone. Furthermore, the copper / graphene composite mixture provides the system with improved structural integrity with a 200% increase in yield strength and durability. Preferably, the heat recovery devices includes the first inner layer, and the second outer layer deposited on the first inner layer made of copper / graphenecomposite material. In yet a most exemplary preferred embodiment, the second outer layer is deposited on to the first inner layer is accomplished using a continuous alternating high-velocity atomization process in a reducing atmosphere.

[0092] In yet still another particular embodiment, a heat recovery system with the aforementioned heat recovery device with a leak detection mechanism is provided. Preferably, the heat recovery system includes the heat recovery device including a clear PVC end cap connector is designed to allow visual inspection for potential leaks between the first inner layer and the second outer layer barriers, enabling efficient leak detection system.

[0093] In yet still another particular embodiment, a heat recovery system with the aforementioned heat recovery device with concealed layers is provided. Preferably, the heat recovery system includes the heat recovery device with the first inner layer and the second outer layer comprise a copper composite mixture. More preferably, the first inner layer is a conduit made of 99.5% copper or a copper / graphene mixture. Preferably, the second outer layer is made of 99.5% copper or a copper / graphene mixture deposited on the conduit; and, the third insulating layer is a jacket housing surrounding, encasing and concealing the first inner layer and the second outer layer to reduce visibility of the layers comprising copper and deter theft. In a typical embodiment, the system can provide additional protection against environmental damage, and address the increasing demand and cost pressures associated with copper materials.

[0094] In yet still another particular embodiment, a heat recovery system with the aforementioned heat recovery device with inlet / outlet portals to induce turbulent fluid movement is provided. Preferably, the inlet / outlet portals in the heat recover device is capable of inducing turbulent centrifugal movement of the second fluid (for example,potable water) through the helical cut pathway channels in the outer PVC jacket housing, enhancing thermal transfer efficiency by increasing the second fluid’s (or example, potable water) surface area and interaction time with the thermal exchange surfaces (the second outer layer deposited on the first inner layer; the layers preferably made of copper composite mixture material).

[0095] In another particular embodiment, a heat recovery system with the aforementioned heat recovery device is provided with a spirit level. Preferably, the heat recovery system comprises a circular spirit level placed circumferentially on the outer PVC jacket housing, wherein the spirit level ensures critical vertical positioning of the system to maximize efficiency by maintaining the correct alignment of falling water film on the thermal exchange surface (copper composite mixture) surface.

[0096] In other embodiments of the present invention, methods are provided using the aforementioned heat recovery device(s) and system(s). The method(s) include(s) a method of conforming layers; methods for increasing copper composite mixture surface area; a method for maintaining optimal heat transfer; a method for maximizing potable water retention time; a method for reducing material usage in heat recovery systems; and, a method for allowing thinner heat transfer layers.

[0097] In a typical embodiment of the present invention, a method for conforming the first inner layer and the second outer layer of the thermal recovery device and / or heat recovery system described above is provided. The method comprising the steps of 1 ) conforming the first inner layer to transport the first fluid; 2) configuring the second outer layer to transport the second fluid; 3) aligning the first inner layer and the second outer layer with optimized surface contact geometry; and, 4) creating an improved mechanical bond between the first inner layer and the second outer layer.

[0098] Typically, the first inner layer and second outer layer include a metal composite mixture. Preferably, the first inner layer and the second outer layer is a copper composite mixture. In a preferred embodiment, the first inner layer is 99.5% copper and the second outer layer is a 99.5%. In another embodiment, the first inner layer and the second outer layer are both made of a copper / graphene composite mixture. In a typical embodiment of the present invention, the first inner layer can be a conduit or pipe. Preferably, the first fluid is grey drain water and the second fluid is potable water.

[0099] In a preferred embodiment, the mechanical bond can be achieved by creating a roughened surface on the outer surface of the first inner layer. More preferably, grit blasting the outer surface of the first inner layer using Alumina type 80 mm / min mesh size particles. Preferably, when the first inner layer is a conduit or pipe, the roughened outer surface can be achieved by rotating the conduit or pipe at 6 rpm and moving laterally at 1200 mm / min, with a sand / grit dispenser operating at 100 psi air pressure, thereby creating a roughened surface (Ra 10-15) for improved mechanical bonding between the two layers.

[0100] In a typical embodiment of the present invention, a method for increasing copper composite mixture surface area of the thermal recovery device and / or heat recovery system described above is provided. Preferably, the second outer layer is a copper composite mixture layer and applied using the aforementioned method above. A method for increasing the surface area of the second out layer includes the steps of: 1) applying a copper atomization process to the outer surface of the first inner layer; and 2) forming micro-dendritic structures (for example, micro-dendritic copper structures or micro-dendritic copper / graphene mixture structures) on the outer surface of the first inner layer (for example, an inner copper pipe), through the copperatomization process. The method increases the surface area by a factor of 3x to 4x, thereby enhancing thermal transmission between the first inner layer and the second outer layer.

[0101] In a typical embodiment of the present invention, a method for reducing material usage in the thermal recovery device and / or heat recovery system described above is provided. Preferably, the method includes the steps of reducing the total copper density in the system by more than 50% compared to similar existing devices, while maintain or improving thermal energy transfer efficiency to enhance costeffectiveness.

[0102] In yet another typical embodiment of the present invention, a method for maintaining optimal heat transfer of the thermal recovery device and / or heat recovery system described above is provided. Typically, the method includes the steps of: 1 ) cleaning the interior surface of the first inner layer to remove contaminants; and, 2) applying a super hydrophilic and oleophobic coating / film to the interior surface of the first inner layer to enhance hot water film formation on the waste drain copper surface, by increasing wettability and creating a super hydrophilic / oleophobic coating ensuring efficient thermal energy transfer and preventing the buildup of oil or other contaminants. Preferably, the first inner layer is an internal conduit or internal pipe made of a copper composite mixture and is made of 99.5% copper or a copper graphene mixture. In a preferred embodiment, the super hydrophilic / oleophobic coating / film(s) for copper include but are not limited to TiC (Titanium dioxide), SiO (Silica dioxide), GO (Graphene Dioxide), polyvinyl alcohol (PVA), chitosan (CTS), glutaraldehyde (GA) with TiO2 (Titanium oxide) nanoparticles and plasma films using oxygen or ammonia which will react with copper to form hydrophilic / oleophobic functional groups.

[0103] In a typical embodiment of the present invention, a method for maximizing potable water retention time in the heat recovery system using the thermal recovery described above is provided. Preferably, the method comprises the steps of: configuring the outer PVC jacket housing with a helical cut pathway water channel on to the interior surface of the jacket housing, the helical cut pathway having a pitch of 22mm + 2mm and a width of 18.5 + 1.5 mm; and ensuring the helix design prolongs potable water retention time without causing significant pressure loss, not exceeding 3 + 0.5 psi, thereby optimizing heat energy transfer.

[0104] In a typical embodiment of the present invention, a method for providing thinner heat transfer layers of the thermal recovery device and / or heat recovery system described above is provided. Preferably the method to enable thinner copper composite mixture (copper or copper / graphene composite mixture) heat transfer layers in a heat recovery system, the method comprising the steps of: providing a heat recovery system using the aforementioned heat recovery device(s) to operate without leakage or mechanical damage at an operating pressure of about 225 to about 230 psi for up to about 30 minutes; and, providing thinner materials to improve thermal transfer efficiency, the thinner materials are chosen based on the formula:K = (Q L / (AT), wherein, K is thermal conductivity; Q is heat transferred; L is distance between isothermal planes; A is surface are, and AT is the temperature difference. The method can further comprise the steps of: exposing copper or copper / graphene mixture layers to temperatures from about 600 °C to about 700 °C, followed by applying contact with silicon-bearing sand for about 20 - 30 minutes, resulting in a 3x improvement in hardness and a 2.5x increase in compressive yield strength, enabling thinner layers (0.8 - 1.5 mm) to meet the required operating pressures.

[0105] According to a most exemplary embodiment of the present invention, the thermal recovery device preferably is a heat recovery device and is represented in the following figures.

[0106] Referring now to FIGS. 1A, 1C and ID, a schematic diagram(s) illustrating a view(s) of a heat recovery device 100 according to an exemplary embodiment(s) of the present invention. The heat recovery device 100 preferably is a drain water heat recovery device designed to efficiently recover heat from a first fluid (for example, non-potable water, drain water or grey water flow) for reuse in, for example, a domestic hot water system. As shown in FIG. ID, the fully assembled heat recovery device 100 comprises a first inner layer 1 (for example, a non-potable internal drainage pipe) with a second outer layer 2 deposited on the outer surface of first inner layer 1. Preferably, the first inner layer 1 can be referred to hereinafter as an “internal conduit” or “internal pipe” 1, and the combination of the second outer layer 2 deposited on the first inner layer 1 can be referred to hereinafter as “drainage pipe / conduit” or “unit” 20, and terms can be used interchangeably hereinafter. Preferably, the second outer layer 2 deposited on the first inner layer 1 forms a thermal exchange surface.

[0107] In a most preferred embodiment of the present invention, internal conduit or internal pipe 1 comprises a copper composite mixture. Typically, the “copper composite mixture” can be any composite which includes copper, or copper / graphene mixtures thereof. In one preferred embodiment, the internal conduit comprises a copper composite made of 99.5% copper. In yet another alternative preferred embodiment, the first inner layer (internal conduit or internal pipe) 1 comprises a copper composite mixture made of a copper / graphene mixture.

[0108] In a typical embodiment of the present invention, both the first inner layer (internal conduit or internal pipe) 1 and the second outer layer 2 comprise at least 99.5% copper complying with NSF61 / ANSI / CAN 600:2023 standard and 0.5% can include typical “impurities” or minority metals known to those skilled in the art, for example, metals, alloys, elements etc. In still yet another embodiment, the 0.5% minority metals can include phosphorous at about 0.025%

[0109] In yet another alternate preferred embodiment, the copper / graphene mixture can be from 8% copper and 92% graphene. According to an embodiment, a minimum copper composition from about 8% is needed to best align single molecular layer graphene deposits. Preferably, it can be appreciated by those skilled in the art that the higher the percentage of graphene, the greater the thermal conductivity.

[0110] In a preferred embodiment, the second outer layer 2 includes a copper composite mixture and can be referred to hereinafter as the outer copper composite layer 2. More preferably, the second outer layer 2 comprises a copper composite made of copper or a copper / graphene mixture from about 8% copper and 92% graphene.

[0111] In a preferred embodiment of the present invention, the outer copper composite layer 2 preferably is a second layer and is deposited on first inner layer or internal conduit 1. In yet another embodiment of the present invention, the outer copper composite layer 2 is so closely conformed around the internal conduit 1, that reference made to the “drainage pipe” or “non-potable draining pipe” may essentially refer to both the internal conduit or internal pipe 1 and outer copper composite layer 2 as a “unit” 20.

[0112] In a most preferred embodiment of the present invention, referring to “phantom view” FIG. ID, the “unit” 20 is surrounded by (see FIGS. 1A - D) a jackethousing 3 having a helical cut pathway 9 through which the counterflow potable water flows in and out via inlet / outlet connections 7 located on end coupling 6 connected to an external piping / hose (not shown); an end coupling 6 located at each end of the heat recovery device 100, connecting the jacket housing 3 to the drainage conduit 20 and to a clear PVC bolted on end cap 5 at each end of heat recovery device 100. Preferably, an “O” ring 4 is aligned at each end of the heat recovery device 100 between end coupling 6 and end cap 5 to ensure integrity of a seal provided by each “O” ring 4. The heat recovery device can further include a connector 8 at each end for connecting the heat recovery device 100 to an existing drain pipe / plumbing stack.

[0113] According to embodiments of the present invention, the non-potable drainage pipe / conduit 20 includes the first inner layer or internal conduit 1 concentric with an outer copper composite layer 2. The internal pipe 1 component functions as a conduit for the flow of the first fluid. Preferably, the first fluid is hot non-potable greywater. More preferably, the internal conduit 1 is made from a copper composite mixture comprising at least 99.5% pure copper or alternatively a graphene / copper mixture. In a most preferred embodiment, the copper / graphene mixture can be from 8% copper and 92% graphene.

[0114] In a most preferred embodiment of the present invention, the addition of graphene can significantly increase thermal conductivity of the first inner layer or internal conduit or internal pipe 1 by 5 to 8 times.

[0115] In yet another embodiment of the present invention, the first inner layer or internal conduit 1 is a copper composite mixture. Preferably, the internal conduit 1 is a copper pipe comprising at least 99.5% pure copper and can be referred to hereinafter as inner layer / copper pipe 1.

[0116] Typically, the interior surface of the copper pipe 1 can be thoroughly cleaned with special cleaning agents. In yet another embodiment of the present invention, the interior surface of the first inner layer or copper pipe 1 can further include at least one coating. Preferably, a (super) hydrophilic oleophobic coating can be applied using methods to assure that the first fluid, for example non-potable hot water, can cascade down from the top of the pipe, forming a continuous film of hot non-potable water, thus preventing water bead formation and thus assuring maximum possible thermal transmission to the outer copper composite layer 2.

[0117] According to embodiments of the present invention, super hydrophilic / oleophobic coating / film(s) for copper include but are not limited to TiCh (Titanium dioxide), SiCh (Silica dioxide), GO (Graphene Dioxide), polyvinyl alcohol (PVA), chitosan (CTS), glutaraldehyde (GA) with TiO2 (Titanium oxide) particles and plasma films using oxygen or ammonia which will react with copper to form hydrophilic / oleophobic functional groups.

[0118] In yet still another embodiment of the present invention, methods for applying the coating(s) including super hydrophilic / oleophobic film(s) are disclosed. Depending on the super hydrophilic / oleophobic film(s) applied, methods for the application include but are not limited to plasma formation, sol-gel deposition, spin coating, dip coating or spray coating or any other methods known to those skilled in the art. In yet another embodiment of the present invention, special cleaning agents refer to the chemistry specific to surface cleaning and deoxidizing the interior surface of the copper pipe 1 to prepare for optimized adhesion to the copper. According to embodiments of the present invention, the specifics as to which special cleaning agents are used typically depends on which type and deposition method are selected to deposit the hydrophilic film.

[0119] In yet a preferred embodiment of the present invention, surrounding the internal conduit 1 is the outer copper composite layer 2, precisely positioned in close conformity and deposited on to the internal conduit 1 to optimize thermal transmission. Preferably, the outer copper composite layer 2 is made from 99.5% pure copper or alternatively a graphene / copper mixture. In a typical embodiment of the present invention, both the internal conduit 1 and the outer copper composite layer 2 comprise at least 99.5% copper as required by NSF61 / ANSI / CAN 600:2023 which is included herein in its entirety (for example, 0.5% includes the balance of the minority metals and their maximum concentration are provided within).

[0120] Preferably, it can be appreciated by those skilled in the art that the higher the percentage of graphene, the greater the thermal conductivity. In a most preferred embodiment, the copper / graphene mixture can be from 8% copper and 92% graphene. According to an embodiment, a minimum copper composition from about 8% is needed to best align single molecular layer graphene deposits.

[0121] Preferably, the outer copper composite layer 2 is engineered and deposited with a thickness and material composition chosen for enhanced heat transfer efficiency. In yet still another preferred embodiment of the present invention, the exterior surface of the first inner layer or internal conduit 1 is modified by depositing the outer copper composite layer 2 to increase the surface area by a factor of three compared to an unmodified outer surface of first inner layer or internal conduit 1, thereby maximizing heat exchange capabilities. For example, the outer copper composite layer 2 may be applied over the outer surface of internal conduit 1 by a thermal spraying coating technique to maximize heat exchange performance.

[0122] In still yet another preferred embodiment of the present invention, the outer copper composite layer 2 may be configured with a thickness of 0.25 mm andthe internal conduit 1 configured to have a thickness of 1.2 mm. It can be appreciated by those skilled in the art that the thinner the combination of the internal conduit 1 and outer composite layer 2 the higher the efficiency of thermal transmission between the heated non potable water and the cold potable water stream. In a most preferred embodiment, the total thickness of the combined internal conduit 1 and the outer copper composite layer 2 must meet a pressure testing of 230 psi for 15 minutes without producing any fractures in either layer resulting in water leakage.

[0123] Referring now to FIGS. 1A-C, further details are provided on the inlet and outlet connections 7 engaged with inlet and outlet portals 17 located on end coupling 6 for flow of a second fluid, for example, potable water, into the heat recovery device 100. The helically cut pathway 9 within the jacket housing 3 allows potable water to maintain proximal contact with the outer surface of conduit unit 20 (i.e. internal conduit 1 with outer copper composite layer 2), maximizing retention time. Also shown are end cap(s) 5, and drain connector(s) 8.

[0124] According to an embodiment of the present invention, an exploded perspective view of one end of the device 100 is shown in FIG. 2A, wherein the internal copper pipe 1 and a second copper composite layer 2 are mechanically connected (i.e. via a mechanical bond mechanism) and are positioned by press fit tightly inside the jacket housing 3. Preferably, the heat recovery device 100 can further include “O” ring 4; end cap 5; and corresponding coupling 6; wherein both end cap 5 and corresponding coupling 6 are positioned at the end of each device 100. In a preferred embodiment, “O” ring 4 can be any known circular gasket known to those skilled in the art to form a seal between connecting parts. Preferably, the “O” ring 4 can form an interface with the jacket housing 3, the internal copper pipe 1, andthe coupling 6, sealed by end cap 5. Typically, coupling 6 and end cap 5 are clear PVC.

[0125] Referring to FIG. 2A, preferably, end cap 5 comprises a clear PVC end cap connector designed to allow visual inspection for potential leaks between the internal copper pipe 1 and outer copper composite layer 2 enabling efficient leak detection and maintenance of the heat recovery device 100. According to an embodiment of the present invention, end cap 5 can include a sufficient quantity of bolts 5a-e to secure end cap 5 to each end of the heat device 100 to withstand water pressure and deter and leakage between the grey and potable water sources. Any type of bolts or connectors known to those skilled in the art can be used (for example, screws, fasteners, etc.)

[0126] Referring to FIG. 2B, the helically cut pathway 9 within the interior surface of jacket housing 3 ensures that potable water follows a circular pattern around the circumference of the “unit” 20 (the first inner layer or internal conduit 1 and the outer copper composite layer 2, together). The helically cut pathway 9 is formed into the interior surface of the jacket housing 3 as an open channel and when the jacket housing is positioned / engaged on the unit 20, the circumferential surface of the unit 20 (i.e. exterior surface of outer layer 2) meets the inner facing channel edges 9a of the helically cut pathway 9 such that the pathway 9 becomes a closed channel for the potable water flow. This configuration makes it possible for the potable water to directly contact the exterior circumferential surface of outer layer 2 and in a circular manner, enhancing thermal transfer.

[0127] Referring to FIG. 3, a perspective partial end view of the non-potable drainage pipe 20 of the heat recovery device 100 comprised of the first inner layer or internal conduit 1 and second outer layer or outer copper composite layer 2 is shownaccording an embodiment of the present invention. The internal conduit 1 and copper composite layer 2, together also known as the “unit” 20, typically have an elongated length longer than the jacket housing 3; and when assembled, extend out from the jacket housing 3 at each end of heat recovery device 100 (see FIGS. 2A-2B).

[0128] In a preferred embodiment of the present invention, internal conduit / pipe 1 is longer than copper composite layer 2. The following is example according to an embodiment of the present invention, wherein the total copper pipe length 1 is 965.2mm (38in) long. The second copper layer 2 is 925.2 mm long which is 40 mm less than the copper pipe 1. Approximately 20mm on each end of the pipe 1 is not covered by the second copper layer 2 as that layer 2 is far too rough to provide a good water tight seal with the "O" ring 4. Therefore 20 mm are at each end of the pipe is not coated with the second layer 2 as the inner pipe layer 1 is much smoother having much less roughness and thereby provides a greater and more dependable sealing with the "O" ring 4. See also FIGS. 2B, 4 5A and SB which illustrates the hidden line that depicts the approximate end point of the second copper layer 2 and where the remaining portion of the inner pipe 1 thereafter is exposed. The “O” ring is positioned directly around the exposed exterior of the inner pipe 1 as shown for an effective seal.

[0129] Typically, the first inner layer or internal conduit 1 has a thickness greater than the second outer layer or copper composite layer 2. Preferably, the first inner layer is an internal conduit or internal pipe or copper pipe 1 configured with a thickness ranging from about 1 mm to about 2 mm, surrounded by the second outer layer or copper composite layer 2 with a thickness from about 0.025 mm to about 0.05 mm. More preferably, copper composite layer 2 is deposited on to internal conduit 1. It can be appreciated by those skilled in the art that the thinner the combination of the internal conduit 1 and outer composite layer 2 the higher theefficiency of thermal transmission between the heated non potable water and the cold potable water stream. In a most preferred embodiment, the total thickness of the combined internal conduit 1 and the outer copper composite layer 2 must meet a pressure testing of 230 psi for 15 minutes without producing any fractures in either layer resulting in water leakage.

[0130] Preferably, the outer copper composite layer 2 is mechanically applied to the outer surface of the internal conduit 1, by any methods known to those skilled in the art to deposit a metal layer, including for example, via a thermal spraying technique; more preferably an ARC spray method. Typically, the ARC spray method deposits a copper composite layer 2 on to the internal conduit 1 through high-speed fusion with the surface micro-morphology of the pipe. In a typical embodiment of the present invention, it can be understood to those skilled in art that although the adhesion achieved is robust and mechanically sound, the resulting outer copper composite layer 2 can he uniformly removed from the outer surface of the internal conduit 1 when desired. According to other embodiments of the present invention, alternative techniques such as plasma spraying or vacuum deposition may also be employed.

[0131] According to an embodiment of the present invention, FIGS. 4, 5A and 5B illustrate respectively a cross-sectional view of the device, an enlarged perspective partial sectional view of one end of the device shown in FIG. IB and another enlarged perspective partial sectional outline view of one end of the device as cut through an inlet / outlet portal and shown without a drain connector 8. In particular, FIG. 4 illustrates the jacket housing 3 with helical cut pathway 9 which surrounds and rests flush against the outer surface or circumference of the second layer 2 of the drainage pipe / conduit 20 of the heat recovery device 100 according to a preferredembodiment of the present invention. The drainage conduit 20 is configured for receiving the flow of non-potable water separately from and without any direct contact with the fluid flow (e.g. potable water) inside the jacket housing 3. The drainage conduit 20 comprises first layer internal conduit or internal pipe 1 with an outer copper composite layer 2 according to a preferred embodiment of the present invention. The conduit 20 comprises a first end 21 and a second end 22 at which non- potable water is received and exits respectively.

[0132] Preferably, the jacket housing 3 has an inner diameter matching (i.e. abutting) the outer diameter / circumferential surface of the “unit” 20 (internal conduit 1 and outer copper composite layer 2), preventing potable water from bypassing the helical path 9 taken by the cold potable water flow. This configuration is further illustrated in the exploded view of FIG. 2B, and in FIGS. 5A-5B, where the internal conduit / first layer 1 and outer copper layer 2 extend from jacket housing 3. As shown in FIG. 4, the jacket housing 3 comprises an inlet housing end 31 and an outlet housing end 32 at which potable water is received and exits respectively.

[0133] Typically, according to an embodiment of the present invention, the jacket housing 3 is the outermost insulating layer of the heat recovery device and is comprised of plastic, more particularly, PVC (polyvinyl chloride), or other similar material safe for contact with potable water. Preferably, the jacket housing 3 is made of PVC, and tightly surrounds internal copper pipe 1 and outer copper layer 2 assembled as a press fit.

[0134] In a most preferred embodiment of the present invention, the inner diameter interior surface of jacket housing 3 is machine cut with a helical rectangular cut pathway 9 (or open channel) for transporting cold potable water flow such that the cold potable water circulates continuously around the exterior circumferential surfaceof conduit unit 20 (internal conduit 1 and outer copper layer 2), thus increasing cold water retention time while causing only minimal pressure drop (1 or 2 psi). This preferred embodiment design enhances heat exchange efficiency.

[0135] As shown in FIGS. 5A-5B, and in the cross-sectional side view of FIG. 5D taken along and in the direction of the line [B-B] in FIG. 5C (shown without the conduit 20 for visibility), the rectangular cut pathway 9 is illustrated according to an embodiment of the present invention. The rectangular cut pathway 9 into the interior surface of the housing 3 provides for a consistent and uniformly thick outer wall 35 of the jacket housing 3 to meet minimum code requirements for pressure. Importantly, the rectangularly cut pathway 9 provides for a uniform 5mm thick outer wall 35 which will meet a 235 psi pressure test. The helically cut rectangular pathway 9 is formed into the interior surface of the jacket housing 3 as an open channel and when the jacket housing is positioned / engaged on the unit 20, the circumferential surface of the unit 20 (i.e. exterior surface of outer layer 2) meets the inner facing channel edges 9a of the rectangular cut pathway 9 such that the pathway 9 becomes a closed channel for the potable water flow. The potable water thereby directly contacts the exterior surface of outer layer 2 and in a circular manner for efficient heat transfer and recovery. Furthermore, the jacket housing 3 serves to insulate the potable water flow and prevent thermal loss to the atmosphere. In yet still another embodiment of the present invention, a majority of the internal conduit 1 and outer copper layer 2 are concealed within the jacket housing 3, thus reducing the visibility of the copper composite and deter the potential of theft.

[0136] As shown in FIGS. 6A - 6B and in FIGS. 2A-2B, 4, 5A and 5B, coupling 6 is configured to seamlessly match the internal copper pipe 1 and outer copper layer 2 to prevent disruption of the grey water film flowing down the internal copper pipe 1.When assembled, the end coupling 6 at its smaller diameter section side 11, receives the ends (21, 32 or 22, 31) of both the conduit unit 20 and the jacket housing 3; and the larger diameter section 10 face of the end coupling 6 abuts the flange face 18 of the end cap 5. Each terminal end 21, 22 of the conduit unit 20 (exposed internal copper pipe 1 portion) is attached via a corresponding end coupling 6, surrounded by the “O” ring 4, to a corresponding end cap 5. According to the embodiment of the present invention, the end coupling 6 preferably is comprised of a clear PVC. Use of a clear PVC pipe end cap 5 also provides a visible means of leak detection between the inner and outer copper pipe barriers.

[0137] As further illustrated, the end coupling 6 comprises an inlet / outlet portal 17 to direct inflow and outflow of the potable water. When the end coupling 6 is engaged with a jacket housing end 31, 32, the portal 17 is in fluid communication with the helical cut pathway 9. The inlet / outlet portals 17 are configured and designed to induce turbulent centrifugal movement of the potable water through the helix cut pathway 9. As shown in FIG. 5B and 5D, the inlet / outlet portal 17 comprises a transition 40 where a circular configuration of the portal 17 transitions to a rectangular configuration on the inside of the coupling 6 to precisely meet the rectangular pathway 9 at the jacket housing end 31, 32. This design causes tubulation and thus better and more uniform exposure of the cold potable inlet water stream to the heat emitted from the conduit 20 (inner pipe 1 with outer layer 2). The portal 17 is shown radially extending from the flanged section of the end coupling 6 and includes a threaded end to correspondingly connect with the potable water inlet / outlet connections 7 (e.g. at connection end 12, see FIGS. 10A-10B). Other configurations in which the portals 17 are formed directly on the jacket housing 3 to meet the helical pathway 9 may be contemplated according to other embodiments as long as fluid flowthrough the jacket housing 3 never comes into direct contact with the fluid flow through internal pipe 1.

[0138] As illustrated in FIGS. 2A-2B, 4, 5A, 5B and 5D, the “O” ring 4 of the device according to a most preferred embodiment of the present invention, isolates the internal copper pipe 1 and outer copper layer 2 from the PVC jacket housing 3 and connects the end coupling 6 with end cap 5. The smaller diameter section 11 side of the end coupling 6 is configured to surround the exterior surface / outer circumference of the jacket housing 3. The end coupling 6 is configured so that an exposed end 21, 22 of the conduit 20 (internal pipe 1 exposed portion) passes through the end coupling 6 and though the “O”- ring 4 to end inside the end cap 5, while an end of the jacket housing 31, 32 abuts an edge 16 of the internal diameter of the coupling 6 (See FIGS. 6A, 2B and 5A). The configuration of the end coupling 6 facilitates the tight connection of the jacket housing 3 to the exterior surface of the conduit 20.

[0139] According to an embodiment of the present invention, FIGS. 8A - 8B illustrate a front and side view of the circular “O” ring 4. The “O” ring 4 component serves multiple critical functions. First, it maintains the potable water inlet pressure without allowing leakage from the PVC jacket housing 3. Second, it connects the jacket 3 to the internal copper pipe 1 and outer copper layer 2 and the end coupling 6 with grey water inlet / outlet end cap 5. The precision fit and material integrity of this “O” ring seal are crucial to ensuring that there is no leakage between the opposing grey and potable water flows.

[0140] According to embodiments of the present invention, FIGS. 7A-7B, 8A - 8B and FIGS. 2A-2B, 4, 5A-5B exhibit end cap 5, securing and compressing the circular “O” ring 4 to retain potable water flow within the PVC jacket housing 3 under normal operating water pressure. To further ensure the integrity of the sealprovided by the circular “O” ring 4, the end cap 5 is placed over the “O” ring 4. The end cap 5 fits over the “O” ring 4 placed into an “O” ring groove 15 located on the face 10 of inlet / outlet end coupling 6 (see FIG. 6A). Threaded bolts 5a-e passing through the faces 10, 18 of both the end cap 5 and end coupling 6 are tightened, thus providing compression of the “O” ring 4 material to prevent any potential leaks. According to an embodiment, each end cap 5 is made of clear PVC.

[0141] As shown in FIGS. 9A - 9B, the connector 8 for the drain pipe / plumbing stack (not shown) to the device 100, features an internal rubber compression seal and stainless-steel hose clamps for a watertight joint with the end cap 5, according to an embodiment of the present invention. As shown in FIG. 7B , the end cap 5 comprises a terminal end section 19 protruding from the flange side, configured for joining with the connector 8. See FIG. 2B and FIGS. 4, 5A further showing how the connector 8 is engaged with the end cap 5 and partially overlaps the terminal end section 19.

[0142] FIGS. 10A - 10B illustrate enlarged views of the hose coupling / connections 7 which engage with inlet / outlet portals 17 for the inlet and outlet of potable water into the PVC jacket housing 3 (see FIG. IB and FIG. 2B), featuring P? inch NPT threads on one end 12, according to an embodiment of the present invention. At each end 31, 32 of the PVC jacket housing 3, the helical path openings 9 are in fluid communication with the inlet and outlet portals 17 of the end couplings 6 (see also FIG. 5B and 5D) for potable water inlet and outlet, and which engage with the inlet and outlet connections 7. These inlet / outlet portal connections 7 allow for the entry and exit of potable water into and out of the PVC thermal jacket housing 3 via the end couplings 6. The connections 7 have a 0.5-inch NPT thread on one end 12 to be screwed into the side openings / portals 17 of the end couplings 6. Theother end of the outlet / inlet connection 7 can be designed to meet the requirement of the purchaser / consumer (for example, to fit with external piping / hose (not shown)).

[0143] The drain water heat recovery device 100, system and methods described according to embodiments of the present invention achieve a solution for conforming internal copper pipe 1, and a second outer copper composite mixture layer 2 together to optimize thermal transmission between opposing water flows. The device 100 increases the outer surface area of the second outer copper composite mixture layer 2 to enhance thermal transmission. The insulating thermal jacket 3 of the device prevents thermal loss to atmosphere and is designed to control potable water flow to increase contact area and residence time between the hot and cold counterflowing water streams and thereby improves thermal transfer. Moreover, the device and methods allows for maximizing retention time of potable water flow to facilitate heat energy transfer without causing any significant drop in water pressure.

[0144] In other embodiments of the present invention, the use of a copper I graphene mixture in both the internal conduit 1 and outer copper layer 2 materials further significantly improves thermal transfer. By use of a copper-graphene mixture according to the present invention, efficiencies can be increased by a factor of 3 to 5 pending concentrations and layering of graphene in the mixture.

[0145] The components of the device are designed to facilitate a free and undisrupted flow of dropping hot water film (falling film) onto interior pipe sidewalls. The better the formation of a falling film of water within the drain pipe, the better the performance of the heat recovery. Drain water adheres to the internal walls and falls as an annular film, covering the entire inner surface of the pipe. This falling film maximizes the area for heat transfer, while minimizing the thickness of water through which the heat must be transferred to the walls.

[0146] In another preferred embodiment of the present invention, forming a thin adherent water film on the interior surface of internal copper pipe 1 is necessary to ensure that the device 100 is installed in as perfect a vertical formation as possible. Referring to FIGS. 1A, 11A and 11B, a round spirit level 13 is attached to a flexible and removeable collar 14, which can be attached to the circular profile of the outer PVC jacket housing 3 for this purpose.

[0147] By utilizing the novel cleaning method and application of a hydrophilic / oleophobic coating to the interior surface of the internal copper or copper / graphene pipe 1, hot water film formation is improved on the internal conduit 1 interior surface. The method of drain water heat recovery according to the present invention in use of special cleaning agents to remove any organic materials and subsequently applying a hydrophilic / oleophobic coating better assures hot water film formation on the internal conduit 1.

[0148] The configuration of the device components according to the present invention further results in reducing copper usage to improve cost / savings effectiveness and significantly reduces device weight.

[0149] Throughout the description and drawings, example embodiments are given with reference to specific configurations. It can be appreciated by those of ordinary skill in the art that the present invention can be embodied in other specific forms.Those of ordinary skill in the art would be able to practice such other embodiments without undue experimentation. The scope of the present invention, for the purpose of the present patent document, is not limited merely to the specific example embodiments or alternatives of the foregoing description.

Claims

CLAIMSWhat is claimed is:

1. A heat recovery device to enhance thermal energy transmission between non-potable water and potable water, the device comprising: a conduit for non-potable water drainage having a first end and a second end, the conduit comprising a first layer configured to contact the non-potable water and a second layer deposited on an outer surface of the first layer, wherein the first layer and second layer are comprised of one or more thermally conductive materials, the second layer having a thickness less than a thickness of the first layer; and an insulating jacket housing surrounding the conduit and having an inlet housing end and an outlet housing end, the jacket housing comprising a helical cut pathway into an interior surface of the jacket housing and configured to transport potable water from the inlet housing end to the outlet housing end; wherein an innermost diameter of the jacket housing, formed by inner facing channel edges of the helical cut pathway, is disposed flush against and matches an exterior circumferential surface of the second layer, such that the potable water flowing through the helical cut pathway is exposed to contact the exterior circumferential surface of the second layer.

2. The device according to claim 1, further comprising: a first coupling configured to receive the inlet housing end and the second end of the conduit, the first coupling comprising an inlet portal in fluid communication with the helical cut pathway at the inlet housing end; anda second coupling configured to receive the outlet housing end and the first end of the conduit, the second coupling comprising an outlet portal in fluid communication with the helical cut pathway at the outlet housing end; wherein a length of the conduit is longer than a length of the jacket housing, the conduit disposed within the jacket housing such that the first end and the second end each extend beyond the outlet housing end and inlet housing end respectively.

3. The device according to claim 2, wherein the first coupling and the second coupling are comprised of a clear PVC, the jacket housing is comprised of a PVC, and the helical cut pathway has a rectangular cross section.

4. The device according to claim 1 , further comprising a plurality of attachments at the first end of the conduit, the second end of the conduit, the inlet housing end and the outlet housing end; wherein the plurality of attachments includes a pair of end couplings, a pair of “O” rings, and a pair of end caps.

5. The device according to claim 4, wherein a first end coupling of the pair of end couplings comprises an inlet portal, and a second end coupling of the pair of end couplings comprises an outlet portal, the inlet portal and the outlet portal each connected to a pathway opening located at the inlet housing end and at the outlet housing end respectively; each of the pair of “O” rings disposed between one of the pair of end couplings and one of the pair of end caps, and configured to surround the first end of the conduit or the second end of the conduit respectively; andwherein each of the inlet housing end and the outlet housing end is enclosed within a respective end coupling, and each of the first end of the conduit and the second end of the conduit extends through a respective end coupling and partly into a respective end cap.

6. The device according to claim 4, wherein the plurality of attachments further includes a pair of end connectors, each configured to engage with one of the pair of end caps; and wherein the pair of end caps and the pair of end couplings are comprised of a clear PVC.

7. The device according to claim 1, wherein the thermally conductive materials comprise a metal composite mixture including at least one selected from the group consisting of aluminum, brass, cadmium, copper, graphene, nickel, steel, stainless steel, zinc, and mixtures thereof.

8. The device according to claim 7, wherein the first layer and the second layer each comprise copper.

9. The device according to claim 8, wherein the first layer and the second layer each comprise at least a copper mixture or a copper-graphene composite mixture.

10. The device according to claim 1, wherein first layer and the second layer are mechanically bonded together.

11. The device according to claim 1, wherein an interior surface of the first layer further comprises at least one super hydrophilic / oleophobic coating.

12. A thermal recovery device to enhance thermal energy transmission between two fluids, the device comprising a plurality of layers including: a first inner layer configured to surround and transport a first fluid; a second outer layer deposited on to an outer surface of the first inner layer; wherein the first inner layer and the second outer layer are mechanically bonded and together form a thermal exchange surface layer enhancing thermal transmission; and a third insulating layer surrounding and concealing the second outer layer, the third insulating comprising a helical channel cut into an interior surface of the third insulating layer and configured to transport a second fluid; wherein an innermost diameter of the third insulating layer contacts flush against an exterior surface of the second outer layer; such that the second fluid which flows within the helical channel is exposed to the second outer layer and receives thermal energy from the first fluid.

13. The device according to claim 12, wherein an interior surface of the first inner layer further comprises at least one super hydrophilic / oleophobic coating selected from the group consisting of TiCh (Titanium dioxide), SiC (Silica dioxide), GO (Graphene Dioxide), polyvinyl alcohol (PVA), chitosan (CTS), glutaraldehyde (GA) with TiO2 (Titanium oxide) nanoparticles and plasma films using oxygen or ammonia.

14. The device according to claim 12, further comprising a spirit level attached to an outside surface of the third insulating layer; and wherein the plurality of layers are arranged cylindrically and concentrically in a vertical direction.

15. The device according to claim 12, further comprising: a first coupling disposed at a first terminal end of the device and a second coupling disposed at a second terminal end of the device; wherein each coupling comprised of a clear PVC and configured to centrally receive one of the first and second terminal ends, and maintain a connection of the third insulating layer on the second outer layer; and wherein the first coupling comprises an inlet and the second coupling comprises outlet, the inlet and outlet each fluidly connected to a corresponding end of the helical channel in the third insulating layer.

16. The device according to claim 12, wherein the thermal exchange surface layer includes micro-dendritic structures resulting from deposition of the second outer layer on to the outer surface of the first inner layer such that a surface area of the second outer layer is increased, and wherein the second outer layer has a thickness less than a thickness of the first inner layer.

17. The device according to claim 12, wherein the first inner layer comprises a copper / graphene mixture, the second outer layer comprises a copper / graphene mixture and the third insulating layer comprises a PVC.

18. A heat recovery system to enhance thermal energy transmission between non- po table water and potable water comprising: the device according to claim 1 ; a first connector having an entry side and an exit side, the entry side configured to engage with a non-potable water drainage stack, and the exit side configured to engage with a first end cap, wherein the first end cap receives the first end of the conduit through a first “O”-ring and through a first coupling and wherein the outlet housing end is disposed inside the first coupling, the first coupling including an outlet portal in fluid communication with the helical cut pathway at the outlet housing end; an outlet connection configured to engage with the outlet portal and with a potable water outlet; a second connector having receiving side and emitting side, the receiving side configured to engage with a second end cap, and the emitting side configured to engage with the non-potable water drainage stack, wherein the second end cap receives the second end of the conduit through a second “O”-ring and through a second coupling and wherein the inlet housing end is disposed inside the second coupling, the second coupling including an inlet portal in fluid communication with the helical cut pathway at the inlet housing end; and an inlet connection configured to engage with the inlet portal and with a potable water inlet.

19. A method for heat recovery between non-potable water and potable water using a heat recovery device comprising a conduit configured for non-potable flow in one direction and a jacket housing surrounding and positioned flush against an exterior surface of the conduit, wherein the jacket housing comprises a helical rectangular cut channel in an interior surface along a length of the jacket housing configured for potable water flow in another direction, the method comprising: guiding non-potable water through an inside of the conduit, the non-potable water received at a first end of the conduit and discharged through a second end of the conduit; receiving potable water at an inlet end of the rectangular cut channel of the jacket housing, wherein the inlet end is at an opposite end from the first end of the conduit; circulating the potable water through the rectangular cut channel, the circulating potable water having direct contact with the exterior surface of the conduit; transferring thermal energy from the inside of the conduit to the exterior surface; heating the potable water from the contact with the exterior surface; and emitting the potable water at an outlet end of the rectangular cut channel of the jacket housing.

20. The method according to claim 19, wherein the step of receiving potable water is conducted through an inlet portal disposed on a first coupling engaged with the inlet end and the second end;wherein the step of emitting the potable water is conducted through an outlet portal disposed on a second coupling engaged with the outlet end and the first end; and wherein the first coupling and the second coupling maintaining a connection of the jacket housing with the conduit.