WASTE-HEAT RECIRCULATING SYSTEM, METHOD OF INSTALLATION AND METHOD OF USE THEREOF

Abstract

A waste-heat recirculating system enables waste-heat to be transferred from flue gas to air. The air can be used to heat an enclosed space. The system comprises a housing body, a heat exchanger and a control means. The housing body has a flue-gas flow path and an air flow path. The heat exchanger is positionable or positioned within the housing body for providing a boundary between the flue-gas flow path and the air flow path. The fluid-circulating means enables transfer of waste-heat from the flue gas to the air via the heat exchanger by circulating the flue gas along the flue-gas flow path and/or the air along the air flow path; and a control means for controlling the waste-heat recirculating system, wherein the control means includes at least one of: a sensor, a logic processor module, an alarm module, a memory module, a communication module, and a user-interface module.

Claims

1. A waste-heat recirculating system for transferring waste-heat from flue gas from a boiler to air usable to heat ambient air in an enclosed space of a building, the system comprising: a housing body defining a flue-gas flow path therethrough; a heat exchanger formed as a pipe positioned within the housing body for providing a barrier between the flue-gas flow path and an air flow path defined within the pipe; a fan element for transferring waste-heat from the flue gas to the air via the heat exchanger by circulating the air along the air flow path; ducting connected to the housing body for directing the air from the air flow path to the said enclosed space; and a control means for automatically controlling the waste-heat recirculating system, wherein the control means includes: a temperature sensor being positioned at, in, on, through or adjacent to the ducting for measuring a temperature therein, a logic processor module configured to output a control signal to the fan based on an output of the temperature sensor, and a communication module for enabling communication between at least the temperature sensor and the logic processor module.

2. A waste-heat recirculating system as claimed in claim 1, further comprising at least one of: an alarm module; a memory module); and a user interface module.

3. A waste-heat recirculating system as claimed in claim 1, further comprising a carbon monoxide sensor communicable with the communication module.

4. A waste-heat recirculating system as claimed in claim 1, wherein the communication module includes at least one of: a Wi-Fi sub-unit, a Bluetooth sub-unit, Near-Far Communication sub-unit, an Internet sub-unit, a receiver, a transmitter, and a transceiver.

5. A waste-heat recirculating system as claimed in claim 1, wherein the communication module is adapted to be communicable with a software application via which a user can provide an input to the system and/or receive an output from the system.

6. A waste-heat recirculating system as claimed in claim 1, wherein the pipe of the heat exchanger is formed of a thermally conductive material.

7. A waste-heat recirculating system as claimed in claim 6, wherein the thermally conductive material includes copper.

8. A waste-heat recirculating system as claimed in claim 1, wherein the housing body is dimensioned to be engaged with a domestic flue.

9. A waste-heat recirculating system as claimed in claim 1, wherein the housing body is dimensioned to be engaged with a commercial or industrial flue.

10. A waste-heat recirculating system as claimed in claim 1, wherein the housing body further comprises a handle for enabling a user to grasp the housing body.

11. A waste-heat recirculating system as claimed in claim 1, wherein the control means includes control valving.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The invention will now be more particularly described, by way of example only, with reference to the accompanying drawings, in which:

[0021] FIG. 1 shows a schematic representation of one embodiment of a waste-heat recirculating system in accordance with the first aspect of the invention, in-use, installed in a building having a boiler, and the waste-heat recirculating system being in communication with a third-party device;

[0022] FIG. 2 is a perspective representation of part of the waste-heat recirculating system in accordance with the first aspect of the invention, in-use, connected to a boiler, with the control means and fluid-circulating means omitted for clarity;

[0023] FIG. 3 is a further perspective representation of the waste-heat recirculating system of FIG. 2;

[0024] FIG. 4 illustrates a side representation of the waste-heat recirculating system of FIG. 2, with part of a heat exchanger within a housing body of the waste-heat recirculating system shown as an outline in dotted lines;

[0025] FIG. 5 is a front representation of the heat exchanger of FIG. 4; and

[0026] FIG. 6 is a perspective representation of the heat exchanger of FIG. 4.

DETAILED DESCRIPTION OF THE INVENTION

[0027] Referring firstly to FIG. 1, there is shown a system, indicated generally at 110, installed within a building 112. The system 110 in-use enables waste-heat to be captured from a first exhaust fluid 114. The system 110 in-use further enables the waste-heat to be transferred to a second fluid 116. In other words, the system 110 may recirculate heat. Thus, the system 110 may be referred to as a waste-heat recirculating system, a recycling waste energy system, a heating system, a heat recirculating system, a heat recapture assembly, or a recuperator.

[0028] The building 112 has at least one source of first exhaust fluid 118. In the illustrated example, the source of first exhaust fluid 118 is preferably a boiler but any alternative to a boiler may be considered, such as a fireplace, furnace or kitchen hob. The system may be connected with or positioned in or on a flue 120, for example to capture the waste-heat from the combustion gas.

[0029] The first exhaust fluid 114 may include a gas, a liquid, or a combination thereof, such as liquid droplets suspended in a gas. The first exhaust fluid 114 is here the flue gas generated by the source of first exhaust fluid 118.

[0030] The second fluid 116 may include a gas. Preferably, the second fluid is air, such as ambient air.

[0031] The second fluid 116 may be used to heat one or more, preferably enclosed, spaces 122. The enclosed space 122 maybe a space within a building, such as a room, or within a construction such as a marquee. For example, the enclosed space 122 may be one or more of: a loft or attic space, an underfloor cavity, a wall cavity, a room, or any other suitable enclosed space. In FIG. 1, the system 110 is used to heat an under floor cavity 122a and an attic space 122b.

[0032] The system 110 includes a connector 124, ducting 126, a power source 128, a housing body 130, a heat exchanger 132, fluid circulating means 134, control means 136 and a one or more additional electronic components 138, but any of the above may be omitted and/or a plurality of any of the above may be provided.

[0033] The connector 124 in-use enables the system 110 or part thereof to be connectable or connected to a power source 128. The connector 124 may be an electrical cable, by way of example.

[0034] If provided, ducting 126 in-use provides a conduit for a fluid to and/or from the housing body 130. The fluid is the second fluid 116, that is, air. The ducting 126 may thus be used to distribute fluid to one or more locations and/or bring fluid to the housing body 130. The ducting 126 may enable fluid to be moved to and/or from a remote location. The ducting 126 may comprise thermally conductive material and/or non-thermally conductive material. The ducting 126 may comprise electrically-conductive and/or non-electrically conductive material. The ducting 126 may include one or more ducts. A duct may have at least one duct inlet and least one duct outlet.

[0035] If provided as part of the system 110, the power source 128 in-use can power or energise part or all of the system 110. The power source 128 may include at least one battery. Additionally or alternatively, the power source 128 may be a generator or an electrical mains. For example, the power source 128 may be connected to the electrical supply of the boiler.

[0036] The housing body 130 in-use provides a protective shell around all or at least a subset of the components of the system 110. The housing body 130 includes at least one and preferably a plurality of walls, and at least one aperture but any of the above may be omitted and/or a plurality of any of the above may be provided. For example, in a modified embodiment, an existing venting conduit or flue may form the housing body. The housing body may also be referred to as a flue chamber. In a further modification, the housing of the source of first exhaust fluid, such as the boiler housing, may provide the housing body.

[0037] In the illustrated embodiment, the housing body 130 has, defines or encloses at least part of a first-exhaust-fluid flow path 140 and at least part of a second-fluid flow path 142.

[0038] As the first exhaust fluid 114 is flue gas in the preferred embodiment, the first-exhaust-fluid flow path 140 may be referred to as a flue-gas flow path. Similarly, where the second fluid 116 is air, the second-fluid flow path 142 may be referred to as an air flow path.

[0039] The housing body 130 defines a chamber or volume. The first-exhaust-fluid flow path 140 and/or the second-fluid flow path 142 extend through the volume.

[0040] Once again, as the first exhaust fluid 114 is preferably flue gas, the first-exhaust-fluid entry aperture 144a and the first-exhaust-fluid exit aperture 144b may be referred to as a flue-gas entry aperture and a flue-gas exit aperture, respectively. Correspondingly, if the second fluid 116 is air, the second-fluid-entry aperture 146a may be referred to as an air entry aperture or air inlet. The second-fluid-exit aperture 146b may be referred to as an air exit aperture or air outlet.

[0041] In FIG. 1, each first-exhaust-fluid entry aperture 144a and each first-exhaust-fluid exit aperture 144b are substantially opposite each other. The first-exhaust-fluid entry aperture 144a may be located in a floor of the housing body 130. The first-exhaust-fluid exit aperture 144b may be located in a ceiling of the housing body 130. The second-fluid-entry aperture 146a may be located in a lateral wall of the housing body 130. The second-fluid-exit aperture 146b may be located in a floor of the housing body 30. Alternative locations for any of the apertures may be envisioned.

[0042] The first-exhaust-fluid flow path 140 is the path along which the first exhaust fluid 114 may flow when the system is in-use. The first-exhaust-fluid flow path 140 extends entirely through the housing body 130, without being split into multiple pathways.

[0043] The second-fluid flow path 142 is the path along which the second fluid 116 may flow when the system is in-use. If any ducting 126 is provided, the ducting 126 may extend the second-fluid flow path 142. The second-fluid flow path 142 may optionally fork into path sub-portions and/or path sub-portions may fuse together.

[0044] The system 110, and more preferably the housing body 130 thereof further comprises at least one graspable element but this is optional. The graspable element is not visible in FIG. 1. The graspable element enables at least the housing body 130 to be easily and securely grasped in-use, such as by a user or a robot. The graspable element here includes at least one handle or handle element.

[0045] Optionally, the graspable element may include or be formed at least in part of an insulating material, such as a thermally insulating and/or electrically insulating material. Plastics, such as silicone, are examples of an insulating material. In other words, a thermally insulating material does not permit any or any substantial heat transfer. An electrically insulated material prevents or inhibits the flow of electricity within. The user can grasp the graspable element with little to no risk of burn and/or electrocution injury, for instance if the system 110 or part thereof, such as the housing body 30 and/or heat exchanger 132 is hot and/or in contact with a source of electricity.

[0046] The heat exchanger 132 in-use enables heat to be transferred from the first exhaust fluid 114 to the second fluid 116. The heat exchanger 132 preferably provides a barrier or boundary between the first-exhaust-fluid flow path 140 and the second-fluid flow path 142. The barrier is preferably non-permeable, or at least non-permeable to fluids such as liquid and/or gas. The heat exchanger 132 is preferably within the housing body 130. The heat exchanger 132 may be positionable or positioned, such as by being integrally formed or connected to the housing body 130

[0047] In the illustrated embodiment, the heat exchanger 132 includes a length of pipe 148, but any alternative to a pipe may be considered. The 2D or 3D shape of the length of pipe 148 may be selected so as to increase the surface area of the heat exchanger 132 for increasing heat transfer efficiency. In other words, the heat exchanger 132 and more preferably each length of pipe 148 may be designed or configured to achieve maximum surface area. This may enable the second fluid 116 to absorb waste-heat from the first exhaust fluid 114, such as through conduction and/or convection.

[0048] The length of pipe 148 may be at least in part curved along the longitudinal extent of the length of pipe 148. At least part of the length of pipe 148 may form a coil or serpentine structure. More preferably, the length of pipe 148 is at least in part helical.

[0049] Preferably, in FIG. 1, there is a continuous length of pipe 148; however, a plurality of individual lengths of pipe could be considered. The pipe 148 preferably has a uniform width or radius.

[0050] Optionally, the heat exchanger 132 or the pipe 148 may be integrally formed or non-separably connected to the housing body 130. A housing body 130 and heat exchanger 132 forming a single unit may be faster and/or easier to install and/or uninstall. A housing body 130 and heat exchanger 132 may be considered to form a module or modular unit.

[0051] A single length of pipe may be faster and/or easier to install and/or connect to the housing body. A single length of pipe may also result in the corresponding fluid flow path within the housing body being elongated such that any specific volume of fluid may spend a greater length of time within the heat exchanger, at least compared to a heat exchanger having a plurality of distinct pipes in parallel rather than in series, the sum of the lengths of the distinct pipes being equal to the length of the single length of pipe.

[0052] The pipe 148 is preferably formed at least in part of a thermally conductive material. The thermally conductive material may be a metal. Copper is an example of a suitable metal, although any non-copper metal may alternatively be considered.

[0053] The pipe 148 has a longitudinal extent. The longitudinal extent is defined as being the length within the lumen of the pipe 148. In transverse cross-section the pipe 148 may have a curved, and more preferably circular profile. A circular cross-section may improve the flow of fluid within and/or around the length of pipe 148, such as by reducing or eliminating turbulence and/or improving laminar flow.

[0054] The pipe 148 may additionally or alternatively have curvature along at least part of the longitudinal extent. For example, the pipe 148 may comprise a bend. The pipe 148 may have a linear portion along at least part of the longitudinal extent. Optionally, the pipe may be at least in part helical or corkscrew.

[0055] The second-exhaust-fluid flow path 142 extends within the pipe 148. In other words, in-use, the first exhaust fluid 114 flows within the pipe 148. The first-fluid flow path 140 extends around the outside of the pipe 148. As such, the first fluid 114, that is, the flue gas preferably flows around the length of pipe 148.

[0056] If provided, the fluid-circulating means 134 in-use controls the circulation of the air, that is, the second fluid 116 through the system 110. The fluid-circulating means 134 may also be referred to as fluid-controlling means, a fluid circulator, a fluid controller, or a fluid mover. More preferably, the fluid-circulating means 134 may alter the velocity of at least one of the fluids along the second-fluid flow path 142. For example, the fluid-circulating means 134 can cause the velocity to increase from zero. This results in the relevant fluid going from being stagnant to non-stagnant. The velocity can be increased or decreased by the fluid-circulating means 134. More preferably, the fluid-circulating means 134 controls the circulation of the second fluid 116. The fluid-circulating means 134 may thus be used to ensure that a, preferably continuous, supply of second fluid 116, which is preferably air, is passing through the heat exchanger 132 and more preferably through the pipe 148 thereof. The second fluid 116 is then discharged to the enclosed space 122, such as a room, which is being heated up.

[0057] In other words, waste-heat is preferably transferred from the first exhaust fluid 114 to the second fluid 116 via the heat exchanger 132 by entering the housing body 130 such that the first exhaust fluid 114 proceeds along the first-exhaust-fluid flow path 140 whilst the second fluid 116 proceeds along the second-fluid flow path 142, with heat transfer occurring through the heat exchanger 132 from the first exhaust fluid 114 to the second fluid 116.

[0058] The fluid-circulating means 134 may also be able to control whether a fluid can move along, into and/or out of the ducting 126, such as into and/or out of the housing body 130, the enclosed space 122, or further said ducting 126.

[0059] Controlling the location and velocity of fluid can affect the amount of heat transfer from one fluid to another, and therefore affect heating efficiency.

[0060] For instance, if the second fluid 116 has no or substantially no velocity, at least compared to the first exhaust fluid 114, there may be maximal heat transfer from the first exhaust fluid 114 to the second fluid 116. However, no heating of the enclosed space occurs as the second fluid 116 is stagnant and thus does not reach the enclosed space 122.

[0061] At the other extreme, if the second fluid 116 moves with high velocity relative to the first exhaust fluid, little waste-heat is transferred to the second fluid 116 such that little heating of the enclosed space 122 occurs, even though the second fluid 116 reaches the enclosed space 122 or adjacent thereto.

[0062] Intermediate velocities result in varying degrees of heat transfer and heating efficiency. The ability to vary the velocity and location of fluid may provide a means of controlling the temperature the second fluid 116.

[0063] Preferably, the fluid-circulating means 134 includes a fan element 134a, a suction element 134b, a discharge element 134c, and a valve 134d, but any of the above may be omitted and/or a plurality of any of the above may be provided. Alternatively or additionally, the valve 134d may be part of the control means 136.

[0064] A fan element 134a, also referred to as a distribution fan, fluid distribution element, or fan, in-use can cause movement of fluid.

[0065] A suction element 134b can also cause movement of fluid, such as by reducing pressure.

[0066] Similarly, a discharge element 134c can also cause movement of fluid, such as by increasing the pressure or by pushing fluid.

[0067] The valve 134d in-use may selectively enable or prevent movement of fluid by providing a moveable barrier. A one-way valve may be preferable, to only permit one-way movement of fluid, however, a two-way valve could be envisioned. A one-way valve may be desirable to prevent or inhibit heated second fluid 116 accidentally returning to the housing body 130, at least not before being discharged into the enclosed space 122 first. A, preferably calibrated, check valve may be provided at the, each or a said second-fluid-exit aperture 146b or in the ducting 126 downstream of the housing body 130. This valve may enable regulation of the pressure inside the housing body 130. The valve 134d may allow, or alternatively, prevent or inhibit release of second fluid 116, such as air, into or further into the ducting 126. Any suitable type of valve 134d may be envisioned, such as a butterfly valve, a ballcock valve, a check valve, a needle valve, or a pressure relief valve, by way of examples only.

[0068] Optionally, a safety mechanism may be provided in the form of a safety pressure relief valve 134d. The safety pressure relief valve 134d may be installed in or on the housing body 130. If a threshold pressure is exceeded in the housing body 130, such as a safe working pressure threshold, the safety pressure relief valve 134d may open to relieve pressure, such as by venting first exhaust fluid 114 and/or second fluid 116 to the venting space. The venting space may be any of: the flue 120, the space surrounding the system 110, a further space, or any combination thereof.

[0069] The control means 136 in-use controls the waste-heat recirculating system 110 or part thereof. In other words, the operating conditions, distribution of heat and control of the system 110 can be managed via the control means 136.

[0070] For example, the control means 136 may control the fluid-circulating means 134, such as by altering the speed of a fan element 134a, discharge element 134c or suction element 134b. In another example, the control means 136 may actuate a valve 134d from an open condition to a closed condition, and/or vice versa.

[0071] The control means 136 may be electrically energisable. The connector 124 may connect the control means 136 to the power source 128. The control means 136 may thus be or include an electronic operating system. Additionally or alternatively, the control means 136 may be at least in part manually operated.

[0072] The control means 136 may alternatively be referred to as a controlling element, control panel, electrical panel, or controller. The control means 136 includes at least one of: a logic processor module 150, a sensor 152, a communication module 154, an alarm module 156, a memory module 158, and a user-interface module 160, but any of the above may be omitted and/or a plurality of any of the above may be provided. Any further module may be provided. Optionally, the control means 136 may include control valving. The control valving may include at least one said valve 134d.

[0073] The logic processor module 150 in-use receives and/or processes at least one input. Additionally or alternatively, the logic processor module 150 in-use emits at least one output. An input may be data, or a software command line by way of examples only. Similarly, an output may be data, or a software command line by way of examples only. Preferably, the logic processor module 150 may control the fluid-circulating means 134. Optionally, the logic processor module 150 may automatically control the fluid-circulating means 134, without requiring any user input.

[0074] The sensor 152 measures data values of a parameter. The sensor 152 may increase security. The sensor 152 may provide finer control and/or automated control of the system 110. The parameter may be any of: temperature, pressure, a chemical, humidity, any other desirable parameter, and any combination thereof. The chemical may be carbon monoxide, by way of example. The chemical may be a pollutant, such as smoke or nitrogen oxide by way of examples. Measurements may be taken continuously or discretely. If discrete measurements are taken, the measurements may be taken at regular and/or irregular intervals. Preferably, said sensor 152 may be a temperature sensor. The sensor 152 may be a carbon monoxide sensor. The sensor 152 may be a pressure gauge. The sensor 152 may be positioned at, in, on, through or adjacent to any of: the housing body 130, the heat exchanger 132, the ducting 126, the flue 120, the fluid-circulating means 134, the control means 136, any suitable or desired component of system 110, and in any combination thereof.

[0075] For example, a carbon monoxide sensor and/or a pressure sensor may be positioned within and/or downstream of the housing body 130 along the second-fluid flow path 142, to measure the presence of carbon monoxide and/or pressure of the second fluid 116 that is to be vented into an enclosed space 122. A temperature sensor 152 may be located within or outside of the housing body 130 and/or of any ducting 126. For example, a temperature sensor may be located within the enclosed space 122. A temperature sensor may be provided in or in proximity of the housing body 130, for example to enable rapid detection of a dangerous increase in heat indicative of a fire or likely to result in a fire.

[0076] The communication module 154 in-use enables communication between one or more of: components of the control means 136, components of the system 110, and between the system 110 and an, optionally remote, third-party device 162. The communication module 154 may include at least one of: a Wi-Fi sub-unit, a Bluetooth sub-unit, Near-Far Communication sub-unit, an Internet sub-unit, a receiver, a transmitter, and a transceiver, any other suitable means of emitting and/or receiving data, and any combination thereof. Any of the receiver, transmitter, and transceiver may emit radio waves. One-way or two-communication may be envisioned. Wired and/or wireless communication may be envisioned. SMART technology may be used.

[0077] The alarm module 156 in-use can emit an alert or alarm. The alarm module 156 may include a light-emitting element, and/or a sound-emitting element by way of examples. The alarm module 156 may be able to emit an alert to the third-party device 162.

[0078] The third-party device 162 may be a telecommunications device, such as a computer or phone by way of examples only. Optionally, the third-party device 162 may be considered part of the system 110. The user-interface module 160 or part thereof may be provided on the third-party device 162.

[0079] The memory module 158 in-use stores data. For example, the memory module 158 may store any or any combination of: an input, an output, a command line, a data value of a parameter, a reference value of a parameter, user details, or any other desirable data.

[0080] The user-interface module 160 in-use allows a user or robot to interface with the system 110 and more preferably the control means 136 thereof. The user-interface module 160 includes a shut-down element, a user-input element, and a user-output element, but any of the above may be omitted and/or a plurality of any of the above may be provided.

[0081] The shut-down element in-use enables a user or robot to interact with the system 110 to shut down: all or part of the system 110 and/or the source of exhaust fluid, such as in an emergency and/or for safety. The shut-down element may include a button, a toggle, a lever or a handle, by way of examples only.

[0082] Optionally, the shut-down element may include at least one safety valve and/or at least one fire-extinguishing element, such as a sprinkler, by way of examples. It may even be envisioned that the control means 136 and more preferably the alarm module 56 thereof may be able to interact with the shut-down element to automatically shut-down part or all of the system 110 in an emergency. This may increase safety. For example, the alarm module and/or control means 136 may automatically actuate a valve 134d, preferably the safety valve 134d, and/or activate the fire-extinguishing element.

[0083] The user-input element in-use allows the user to provide an input such as data and/or a command, to the control means 136. The user-input element may include any or any combination of: a mouse, a keyboard, a toggle or button, whether digital and/or analogue, a screen, such as a tactile screen, or any other suitable form or combination of features to enable an input to be provided.

[0084] The user-output element in-use allows an output to be provided to a user. The user-output element may include any or any combination of: a screen, an auditory-emitting element such as a speaker, a light-emitting element, or any other suitable element for providing an output.

[0085] The user-interface module 160 or part thereof may be provided at the system 110 and/or at least in part away therefrom, such as by being remote. For example, the user-interface module 160 may be or be on a third-party device 162 such as a computer or phone. The communication module 154 may enable the third-party device 162 to be communicable with the logic processor module 150 and/or the control means 136. The third-party device 162 may have or provide access to a software application. The user can provide an input and/or receive an output through the software application.

[0086] Optionally, the system 110 or any part thereof may comprise heat retaining material or insulation. For instance, the housing body 30 may comprise insulation, preferably thermal insulation for insulating against heat. The insulation may prevent or inhibit waste-heat escaping through a wall of the housing body 130. The insulation may be provided at one or more of walls of the housing body 130. More preferably yet, insulation is provided on an outward facing surface of the housing body 130 but non-outward facing may be envisioned. In modified embodiments, insulation may be provided on an inward-face of a wall, internally within a wall cavity, or formed as part of the material of the wall. Any suitable type of insulation may be envisioned. For example, insulation may be provided a layer of insulating material, a vacuum or partial vacuum.

[0087] Optionally, the system 110 or any part thereof may comprise an anti-corrosion element, not shown. The anti-corrosion element in-use prevents or inhibits corrosion of the system 110 or part thereof. Preferably, all or any subset of parts of the system 110 which may be exposed to a corroding chemical may benefit from having an anti-corrosion element. For example, an anti-corrosion element may be beneficial for any or any combination of: the housing body 130, the heat exchanger 132 or part thereof such as the or a said length of pipe 148, the control means 136, the fluid-circulating means 134 or part thereof such as a fan element, or said sensor 152, and ducting 126. The anti-corrosion element may be provided as a layer or lining of anti-corrosive material. Preferably, the inner surface of the housing body 130, the outer and/or inner surface of the or each length of pipe 148, and the inner surface of any ducting 126 are lined with or protected by an anti-corrosion element, although an anti-corrosion element could be omitted on any of the above.

[0088] In-use, the user may wish to transfer waste-heat from a first exhaust fluid 114 to a second fluid 116 and optionally use the second fluid 116 to heat an enclosed space, thereby saving money, energy and reducing their environmental impact.

[0089] If not already installed, the system 110 may need to be installed first. The system 110 may be in a fully or partially disassembled condition. To install the system 110, any or all of the following steps may be carried out. The system 110 may be installed during construction of a new building or retrofitted in an existing building. The system 110 can be installed in a single domestic housing, large scale domestic apartment blocks, a shopping mall, a hotel, a ship, an industrial factory, or any other suitable environment.

[0090] A housing body 130 may need to be obtained or formed.

[0091] Depending on the use scenario, the housing body 130 of specific dimensions may be required. For example, a housing body 130 may be dimensioned to be engaged with a domestic flue. Alternatively, the housing body 130 may be dimensioned to be engaged with a commercial or industrial flue. As a domestic flue is typically smaller than a commercial or industrial flue, a housing body 130 for use with a domestic flue is typically smaller than a housing body 130 for use with a commercial or industrial flue.

[0092] Preferably, the housing body 130 is distinct from the flue. The housing body 130 may be connected in series with the flue. In an alternative arrangement, the housing body may even be inserted inside a flue.

[0093] Part of the flue may need to be parted, omitted or removed to accommodate the housing body 130. This may occur if the system 110 is retrofitted to an existing heating system 110, for example. In a further arrangement, the housing body may be formed, for example, by altering and repurposing part of the flue. Preferably however, the system 110 and/or housing body 130 thereof is to be installed as an auxiliary unit with a new source of first exhaust fluid 118 having a flue.

[0094] If not already integrally formed with or engaged with the housing body 130, a heat exchanger 132 is engaged with the housing body 130. The heat exchanger 132 is arranged to provide a boundary between the first-exhaust-fluid flow path 140 and the second-fluid flow path 142, here between the flue-gas flow path and the air flow path. In the illustrated embodiment, the heat exchanger 132 is positioned at least in part within the housing body 130.

[0095] Optionally, if ducting 126 is provided, the ducting 126 may be connected to the housing body 130, and more preferably to an aperture thereof. For instance, ducting 126 and/or a duct inlet of a duct may be connected to the second-fluid-exit aperture 146b. A duct outlet of the ducting 126 is positioned at or adjacent to the enclosed space 122.

[0096] Optionally, a control means 136 may also be provided. The control means 136 is preferably arranged or configured to control the system 110. To this end, the control means 136 is or may be arranged or configured to be communicable with any or any combination of components of the system 110. For instance, the control means 136 is communicable or may be arranged or configured to be communicable with the fluid-circulating means 134 or part thereof.

[0097] Preferably, the communication module 154 is adapted or configured to be communicable with a software application via which a user can provide an input to the system 10 and/or receive an output from the system 110.

[0098] If any component of the system 110 is electrically energisable, such as the control means 136, the connector 124 may be provided to connect the system 110 to a power source 128. Optionally, the power source 128 may even be provided.

[0099] The system 110 is now in an installed condition.

[0100] To use the system 110, for example to heat an enclosed space 122, a waste-heat recirculating system 110 is provided in the installed condition.

[0101] Similarly, the second fluid 116 moves along the second-fluid flow path 142. The second fluid 116 enters the housing body 130 via one or more second-fluid entry apertures 146a, optionally after passing through ducting 126 and/or via the fluid-circulating means 134 such as a valve 134d and/or a fan element 134a. In the shown embodiment, the second fluid 116 is preferably air. In other words, ambient air at preferably room temperature, is forced into or drawn into the housing body 130.

[0102] Circulation of the air may be passive. For example, pressure and/or temperature differences may be sufficient to drive movement of one fluid relative to another. Heating the second fluid 116 may cause the second fluid 116 to undergo expansion. However, as the housing body 130 and/or the heat exchanger 132 are preferably non-deformable or substantially non-deformable, and in the absence of any venting, the second fluid 116 is prevented from occupying a larger volume. This results in an increased pressure. Thus, the chamber defined by the housing body 130 may be pressurized. Closing or opening a valve 134d can be used to control where second fluid 116 flows. Venturi effects and/or capillary effects may also be considered.

[0103] Preferably, however, circulation of the air is actively controlled, such as by fluid-circulating means 134 or at least a fan element and/or suction element 134b thereof. For example, the fan element and/or suction element 134b may cause fluid to enter the relevant flow path. In FIG. 1, the fluid is preferably second fluid 116 and the relevant flow path is preferably the second-fluid flow path 142.

[0104] Circulation of the second fluid 116 enables the second fluid 116 to be heated using waste-heat extracted from the first exhaust fluid 114 via the heat exchanger 132.

[0105] One or more sensors 152 may be in or on the first-exhaust-fluid flow path 140 and/or on the second-fluid flow path 142. For example, any or all of: a temperature or thermal sensor 152, a pressure sensor 152, and a carbon monoxide sensor 152 may be positioned on the second-fluid flow path 142 in and/or downstream of the housing body 130 to measure the temperature, pressure and the presence of carbon monoxide in the second fluid 116. The control means 136 and more preferably the logic processor module 150 thereof, may be receiving and processing data, such as values of parameters measured by the sensors 152 and/or an input from a user. Data may be recorded by the memory module 158.

[0106] The control means 136 and more preferably the logic processor module 150 thereof, can issue one or more outputs, such as a data output, via the communication module 154.

[0107] Preferably, the fluid-circulating means 134 is under the control of the control means 136. The control means 136 may, for example, emit an output to alter the speed of a said fan element 134a and/or of a said suction element 134b. The flow rate of the relevant fluid or fluids affects the amount of heat transfer. Thus, the control means 136 can alter the temperature of the second fluid 116 discharged into the enclosed space 122 by altering the flow rate.

[0108] The control means 136 may cause a valve 134d of the fluid-circulating means 134 to be operated from a closed condition to an open condition, or vice versa. Thus, the control means 136 may control one or more valves 134d for altering where a fluid, preferably the second fluid 116, is found within the system 110. Thus, the control means 136 can alter the temperature of the second fluid 116 discharged into the enclosed space 122 by altering the time spent in the housing body 130.

[0109] Once the maximum or desired amount of waste-heat has been transferred from the first exhaust fluid 114 to the second fluid 116, the second fluid 116 is discharged adjacent to or into the enclosed space 122. For example, the second fluid 116 may be discharged into a room. In FIG. 1, the second fluid 116 is discharged into an underfloor cavity below an enclosed space, or a loft space, by way of examples only.

[0110] Optionally, the second-fluid flow path 142 may extend along the ducting 126. If part of the fluid-circulating means 134, such as a fan element 134a, is located on the second-fluid flow path 142 downstream of the housing body 130, the fluid-circulating means 134 may help to move second fluid 116 through the ducting 126.

[0111] The second fluid 116 may thus be heated via waste-heat then pass through ducting 126 before being discharged into adjacent to the enclosed space 122, for example if the enclosed space 122 is remote from the heat exchanger 132 and/or housing body 130.

[0112] Preferably the housing body 130 is or is substantially a cuboid, but any shape may be envisioned. The housing body 130 may be 1 metre in Length by 1 metre (m) in Width by 1 m in Height but any of the Length, Height or Width may be greater or smaller than 1 m, such as 0.5 m, 2 m, 3 m, 5 m. More preferably, the housing body 130 is 200 millimetres (mm) by 200 mm and has a length of 225 mm.

[0113] The graspable element 164, which is preferably a handle, is shown clearly in FIGS. 2, 3 and 4.

[0114] The length of pipe 148 may comprise at least one bend 166 and/or at least a linear portion 168. The linear portions 168 are most clearly visible in FIGS. 4, 5 and 6. Preferably a plurality of, optionally U-shaped, bends 166 are interconnected via a plurality of linear portions 168. Furthermore, there is preferably only one continuous length of pipe 148 or interconnected pipes 148 connected in series, rather than in parallel. The length of pipe 148 may have an, optionally outer, diameter of 1 m or less but greater or smaller diameters may be envisioned. More preferably, the length of pipe 148 has a diameter of 0.5 m or less, and most preferably, a diameter of 15 mm. The total longitudinal extent of the length of pipe 148 may be 10 m or less, but greater than 10 m may be envisioned, such as up to 5 m, up to 8 m, up to 12 m, up to 15 m, up to 30 m by way of examples. More preferably, the length of pipe 148 has a total longitudinal extent of 3.07 m.

[0115] The first-exhaust-fluid entry aperture 144a and the first-exhaust-fluid exit aperture 144b are preferably not opposite each other. Asymmetry means that the first exhaust fluid has to take a longer route to exit the housing body 130, thereby remaining longer in the housing body 130. More preferably, the first-exhaust-fluid exit aperture 144b is in a lateral wall of the housing body 130. Part of the length of pipe 148 may, as shown, extend beyond the housing body 130.

[0116] In this embodiment, the second fluid 116 flows along the second-fluid flow path 142 which is within the length of pipe 148.

[0117] Preferably, neither the second fluid 116 nor the first exhaust fluid 114 has an increased pressure, at least compared to atmospheric pressure within the housing body 130, although either or both fluids may have an increased pressure. In other words, the chamber defined by the housing body 130 is preferably not pressurised.

[0118] Whilst a preferred shape may have been specified for any of the above-described features, any alternative shape may be envisioned in any of transverse or lateral cross-section, longitudinal cross-section, in side view, or in plan view. The shape may be any or any combination of: curved, part curved, non-curved, linear, part linear, non-linear, a broken line, any polygon, whether regular or irregular, having one or more chamfered and/or rounded corners, a triangle, a quadrilateral, such as a square, a rectangle, a trapezium, a trapezoid, a pentagon, a hexagon, a heptagon, an octagon, or any other polygon, a cross, an ellipse, a circle, part circular, an oval, or any abstract shape.

[0119] For example, the housing body may have a fluid-dynamic-enhancing shape. A fluid-dynamic-enhancing may increase the laminarity of fluid flow or, conversely, the turbulence of fluid flow.

[0120] It is therefore possible to provide waste-heat recirculating system which is environmentally friendlier and increases energy efficiency for a given amount of fuel. The system captures waste-heat, which would otherwise be lost. This translates to a greater efficiency, in other words, a greater amount of energy is used for a given amount of fuel. In scenarios where a space is heated by a hot water-based central heating system including a boiler burning fuel, the captured waste heat may displace some of the fuel usage. Less fuel is required, saving costs for the consumer and helping in the fight against climate change. Extracting heat from the exhaust fluid also reduces the temperature of the exhaust fluid, reducing damage to the surrounding infrastructure.

[0121] It is therefore also possible to provide a method of installing a waste-heat recirculating system. The method enables a waste-heat recirculating system to be installed ready for use.

[0122] It is further possible to provide a method of using a waste-heat recirculating system for heating an enclosed space. The system enables heat that would otherwise be wasted to be captured and used to heat an enclosed space, such as a building room. The second fluid being air means that the air can be discharged directly into the enclosed space. No additional infrastructure is required such as radiators.

[0123] The words comprises/comprising and the words having/including when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components, but do not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

[0124] It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

[0125] The embodiments described above are provided by way of examples only, and various other modifications will be apparent to persons skilled in the field without departing from the scope of the invention as defined herein.