HYDROFURNACE

Description

TECHNICAL FIELD

[0001] The present invention relates to hydro furnaces.BACKGROUND

[0002] Since several decades, furnaces have been used to implement combustion for various industrial processes, heating systems, power generation, and the like. Such furnaces are typically operable to burn fuel in the presence of an oxidant, to release heat. A heat exchange medium fluid, such as air, liquid, water, steam, or similar, carries the heat away from the furnace for utilization in the aforesaid applications. Such a furnace is known from CN 205 783 751 U, which discloses a hydro furnace comprising: a combustion chamber comprising a first flue gas outlet (i.e. above the combustion chamber) and a second flue gas outlet (i.e. the upper exit), an inner flue gas pipe having a first lower end and a second upper end, the first end being connected to the first flue gas outlet, a liquid jacket surrounding partially the combustion chamber and the inner flue gas pipe, the liquid jacket comprising a liquid inlet and a liquid outlet.

[0003] However, existing furnaces have some limitations. For example, a typical efficiency of the furnaces is practically below 50 percent, rendering them insufficient for several applications. Such furnaces also suffer from poor fuel economy. In existing furnaces, there occurs inadequate combustion of the fuel, leading to a high by-product (such as carbon dioxide) content, and fuel consumption does not align with generated thermal energy. Presently, to enhance the efficiency and usability of the furnaces, an amount of the fuel being used is increased, but this results in increased expenses for procuring the fuel, as well as a lower ratio of generated heat (output of the furnace) to stored heat (in the fuel).

[0004] Therefore, in light of the foregoing discussion, there exists a need to overcome the aforementioned drawbacks.SUMMARY

[0005] The aim of the present invention is to provide a hydro furnace having a high efficiency and low operational expense. The aim of the present invention is achieved by a hydro furnace defined in the appended independent claim to which reference is made to. Advantageous features are set out in the appended dependent claims.

[0006] Throughout the description and claims of this specification, the words "comprise", "include", "have", and "contain" and variations of these words, for example "comprising" and "comprises", mean "including but not limited to", and do not exclude other components, items, integers or steps not explicitly disclosed also to be present. Moreover, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.BRIEF DESCRIPTION OF THE DRAWINGS

[0007] FIGs. 1A, 1B, and 1C illustrate perspective views of a hydro furnace, FIG. 1D illustrates an exploded perspective view of a portion of the hydro furnace, while FIG. 1E illustrates an exploded view of the hydro furnace, in accordance with an embodiment of the present invention; and FIGs. 2A and 2B illustrate perspective views of a combustion chamber and an inner flue gas pipe of a hydro furnace, FIG. 2C illustrates a back view of the combustion chamber and the inner flue gas pipe, while FIG. 2D illustrates an exploded view of the combustion chamber and the inner flue gas pipe, in accordance with an embodiment of the present invention. DETAILED DESCRIPTION OF EMBODIMENTS

[0008] The following detailed description illustrates embodiments of the present invention and ways in which they can be implemented. Although some modes of carrying out the present invention have been disclosed, those skilled in the art would recognize that other embodiments for carrying out or practising the present invention are also possible.

[0009] In a first aspect, the present invention provides a hydro furnace comprising: a combustion chamber comprising a first flue gas outlet and a second flue gas outlet, an inner flue gas pipe having a first end and a second end, the first end being connected to the first flue gas outlet, the inner flue gas pipe further comprising multiple pipes, each of the multiple pipes comprising a third end and a fourth end, and wherein each of the multiple pipes is arranged to cross through the inner flue gas pipe; a liquid jacket surrounding at least partially the combustion chamber and the inner flue gas pipe, the liquid jacket comprising a liquid inlet and a liquid outlet, and wherein the third end and the fourth end of the multiple pipes are connected to the liquid jacket; and a bypass flue gas pipe having a fifth end and a sixth end, the fifth end being connected to the second flue gas outlet.

[0010] The present invention provides the aforementioned hydro furnace. The hydro furnace described herein has an increased efficiency as compared to existing furnaces, since the hydro furnace is specially designed to effectively maximize harnessing of heat (produced by burning fuel in the hydro furnace) from flue gases. The liquid jacket of the hydro furnace surrounds the combustion chamber as well as the inner flue gas pipe, thus providing a long fluidic path along which liquid circulating in the liquid jacket can maximally absorb the heat from the flue gases. In order to further enhance the efficiency of the hydro furnace, the inner flue gas pipe is designed to include the multiple pipes which are fluidically coupled to the liquid jacket. This beneficially provides multiple surfaces in the inner flue gas pipe from where the heat in the flue gases can be absorbed by the liquid circulating in the multiple pipes. The first and second flue gas outlets of the combustion chamber enable effective expelling of the flue gases out of the combustion chamber to maintain optimal combustion conditions in the combustion chamber, which further enhances the efficiency of the hydro furnace. The bypass flue gas pipe beneficially enables quick ignition of the fuel and directs airflow of the flue gases to maintain optimal combustion temperatures in the combustion chamber. The increased efficiency of the hydro furnace is a synergistic effect of the aforementioned features. Moreover, the hydro furnace described herein enables adequate combustion of the fuel since optimal airflow and temperature conditions are maintained in the combustion chamber. This results in the fuel consumption being well-aligned with thermal energy produced by the hydro furnace. The hydro furnace is simple to manufacture and operate, and has a lesser fuel procurement expense than conventional furnaces for producing a given amount of the thermal energy.

[0011] The term "hydro furnace" refers to a liquid-based furnace, which is a type of a heating system that produces heat by implementing a combustion process and utilizes liquid as a heat transfer medium for effectively harnessing the heat that is produced. The liquid also serves as a coolant since it absorbs the heat produced in the hydro furnace. In an embodiment, the liquid is water. In the hydro furnace, the water may be utilized in liquid form and / or in water vapor form (i.e., steam form). The hydro furnace may also be commonly referred to as a hydronic furnace. The hydro furnace can be a water hydronic furnace, oil hydronic furnace, antifreeze hydronic furnace, or glycol hydronic furnace.

[0012] In the hydro-furnace, the combustion chamber is the heart of the combustion process and is specially designed to contain the combustion process safely and efficiently. The combustion process involves a chemical reaction between a fuel and an oxidant to produce the heat. Flue gases are by-products of the combustion process, and the heat produced in the combustion process raises a temperature of the flue gases to high levels. The (hot) flue gases are required to be expulsed out of the combustion chamber for safe operation of the hydro furnace. The first flue gas outlet and the second flue gas outlet of the combustion chamber facilitate efficient and controlled removal of the flue gases from the combustion chamber. This proper venting of the flue gases resultantly improves combustion efficiency (as optimal combustion conditions are maintained in the combustion chamber) and prevents buildup of excessive heat within the combustion chamber.

[0013] It will be appreciated that the hydro furnace can be operated to perform the combustion process using various fuels available in the environment (such as natural gas, gasoline, wood, biofuel, propane, hydrogen, and the like), and various oxidants (such as air, pure oxygen, oxygen-enriched air, nitrous oxide, steam, hydrogen peroxide, and the like). Use of other fuels and / or other oxidants in the hydro furnace may also be feasible.

[0014] In an embodiment, the liquid is water. Water has high specific heat capacity and thermal conductivity, and therefore it can effectively transfer heat and regulate temperature within the hydro furnace. This property is crucial for efficient heat transfer and maintaining stable operating conditions. Water is also non-toxic and environmentally friendly, making it a safer option compared to some other liquids that may be hazardous or harmful to the environment. Furthermore, water is typically cheaper than many other liquids, which can contribute to cost savings in the operation of hydro furnaces.

[0015] Optionally, the combustion chamber is made using a heat-resistant material that can withstand very high temperatures. Examples of the heat-resistant material include, but are not limited to, a high-temperature alloy, a refractory ceramic material, a refractory cement, or fireclay. For example, the high-temperature alloy may be stainless steel, a nickel-chromium alloy (such as Inconel), a heat-resistant steel, or similar.

[0016] The inner flue gas pipe is enclosed at least partially in the liquid jacket. Optionally, in this regard, the second end of the inner flue gas pipe is arranged outside the liquid jacket. The first end of the inner flue gas pipe is fluidically connected to the first flue gas outlet of the combustion chamber such that the flue gases exiting the combustion chamber at the first flue gas outlet are effectively transferred into the inner flue gas pipe without leakage. The multiple pipes in the inner flue gas pipe provide multiple channels for the liquid circulating in the liquid jacket to flow across the inner flue gas pipe. Notably, the third ends and the fourth ends of the multiple pipes fluidically couple different portions of the liquid jacket with each other, while crossing through the inner flue gas pipe, for enabling such flow of the liquid across the inner flue gas pipe. For example, the liquid may enter the multiple pipes at the third ends and may exit the multiple pipes at the fourth ends, or vice versa. By employing the multiple pipes in the hydro furnace, there is enabled an effective dispersed transmission of the liquid through the inner flue gas pipe via multiple fluidic paths of the multiple pipes, to provide an increased surface area for the liquid (which is the coolant) to absorb the heat from the flue gases. This increased heat recovery of the hydro furnace (by increased heat absorption by the liquid) resultantly increases the combustion efficiency of the hydro furnace.

[0017] Optionally, a length of the inner flue gas pipe which is un-enclosed by the liquid jacket lies in a range of 100 millimetres to 200 millimetres. As an example, the length of the inner flue gas pipe which is un-enclosed by the liquid jacket may be 147 millimetres. Optionally, the inner flue gas pipe is made using a heat-resistant material that can withstand high temperatures. The heat-resistant materials include, for example, steels with a specified minimum yield strength R eH lower or equal to 360 N / mm 2< .

[0018] The "liquid jacket" is an outer enclosure surrounding at least partially the combustion chamber and the inner flue gas pipe. In operation, the liquid circulates in the liquid jacket for absorbing the heat from the flue gases (that are generated in the combustion chamber and exit the combustion chamber through the inner flue gas pipe). So, the liquid absorbs the heat from the flue gases when the flue gases are present in the combustion chamber, as well as when the flue gases are present in the inner flue gas pipe. The liquid is the medium through which the heat generated by the hydro furnace is harnessed. The liquid is provided into the liquid jacket via the liquid inlet and exits the liquid jacket, upon circulation, via the liquid outlet. Since the third end and the fourth end of the multiple pipes are connected to the liquid jacket, there is established a fluidic coupling between the multiple pipes and the liquid jacket, which enables circulation of the liquid in the multiple pipes, for increased heat absorption from the flue gases. The design of the liquid jacket surrounding the combustion chamber and the inner flue gas pipe provides a large area for heat absorption in the hydro furnace, by enabling the circulation of the liquid (i.e., the coolant) around the combustion chamber and the inner flue gas pipe. This fluidic circuit of the liquid in the liquid jacket acts as a heat transfer agent between the hydro furnace and a device utilising heat generated by the hydro furnace. In an embodiment, the liquid is water.

[0019] Alternatively, instead of the water as the heat transfer agent or the coolant, other suitable liquids can be used, such as various thermal or silicone oils, glycol based antifreezes such as propylene glycol or ethylene glycol or a mixture thereof.

[0020] The liquid exiting the liquid outlet is heated and beneficially provides thermal input to said device. Beneficially, thermal energy in the flue gases is harnessed, conserved and utilized to its fullest potential through the circulation of the heat transfer agent (i.e., the liquid or the water). It will be appreciated that by implementing a chimney-like design of the inner flue gas pipe, wherein the liquid jacket surrounds the inner flue gas pipe, the liquid effectively circulates and bends around the flue gases exiting the hydro furnace, thereby effectively accumulating (i.e., harnessing) therein the thermal energy in the flue gases. Optionally, the liquid jacket is made using a heat-resistant material that can withstand high temperatures. The heat-resistant materials include, for example, steels with a specified minimum yield strength R eH lower or equal to 360 N / mm 2< .

[0021] The bypass flue gas pipe is connected at its fifth end, to the second flue gas outlet of the combustion chamber, for enabling quick ignition of the fuel and heating of the inner flue gas pipe. The bypass flue gas pipe creates a more concentrated airflow, which leads to better oxygenation and combustion becomes more efficient, resulting in faster ignition. Increased airflow also leads to higher temperatures which accelerates ignition. The heating of the inner flue gas pipe is enabled by passage of the flue gases which are hot, from the combustion chamber to the inner flue gas pipe via the bypass flue gas pipe. This subsequently provides a natural draft for the flue gases in the hydro furnace. The bypass flue gas pipe beneficially serves as a channel for directing air flow within the hydro furnace. Moreover, the bypass flue gas pipe also enables regulation of the temperature within the combustion chamber to prevent overheating, by directing a portion of the hot flue gases away from the combustion chamber through itself. This is possible since the bypass flue gas pipe is fluidically coupled to the inner flue gas pipe, at its sixth end. The bypass flue gas pipe thus beneficially enables in improving the combustion efficiency of the hydro furnace.

[0022] Optionally, the bypass flue gas pipe is made using a heat-resistant material that can withstand high temperatures. The heat-resistant materials include, for example, steels with a specified minimum yield strength R eH lower or equal to 360 N / mm 2< .

[0023] Optionally, the device utilising the heated liquid exiting the liquid outlet is one of: a boiler, a radiator, a heated floor device. Other feasible examples of devices that can utilise the heated liquid are also well within the scope of the present invention. As an example, the heated water exiting the liquid outlet may be utilised by the boiler, for heating residential buildings (or other premises) having a size such as 100 square metres, 150 square metres, 200 square metres, 250 square metres, 300 square metres, or similar. Such heating can be performed under any conditions, including lack of electricity and specific materials.

[0024] Optionally, the combustion chamber comprises a base, four sides and a top part opposite to the base, wherein the top part comprises the first flue gas outlet and the second flue gas outlet, and wherein the liquid jacket surrounds the combustion chamber from at least three sides and at least partially from the top part. This means that the inner flue gas pipe and the bypass pipe are arranged above the combustion chamber (as they are connected to the first flue gas outlet and the second flue gas outlet in the top part of the combustion chamber). Providing the first flue gas outlet and the second flue gas outlet on the top part of the combustion chamber enables in safely expelling the flue gases out of the combustion chamber. This improves safety and efficiency of the combustion process implemented in the combustion chamber. Optionally, the four sides are arranged perpendicularly with respect to the base. Optionally, at least one of the four sides is fully or partly openable. In this regard, the at least one of the four sides has at least one opening for a door, a sliding shutter, or similar. The at least three sides and at least a portion of the top part which is surrounded by the liquid jacket serve as heat exchange surfaces through which the heat is absorbed by the liquid (circulating in the liquid jacket) from the flue gases. Such a construction of the combustion chamber enables provision of the fuel into the combustion chamber with ease, provides a natural upward passage for expulsion of the flue gases from the combustion chamber, and maintains a cool uniform temperature on an outermost surface of the hydro furnace by way of the liquid jacket surrounding a considerable portion of the combustion chamber. Optionally, a temperature of the outermost surface of the hydro furnace is less than 50 degrees Celsius. For example, the temperature of the outermost surface of the hydro furnace may be 5, 10, 15, 20, 25, 30, 40, 45, or 48 degrees Celsius. It will be appreciated that other feasible values of the temperature less than 50 degrees Celsius are well within the scope of the present invention.

[0025] Optionally, the base of the combustion chamber holds thereon a water container, at least when the hydro furnace is in operation. The water container could be implemented as a slidable container element, a detachable container element, or similar, into which water is placed. In this regard, the base could be fitted with a support structure for holding the water container. The water container may, for example, be a water tray that is slidable. The water in the water container enables improved heat transfer, temperature regulation, and enhanced control of the combustion process. Furthermore, optionally, the combustion chamber further comprises a grid into / upon which the fuel is placed. The grid provides a stable platform for holding the fuel (ensuring that it remains in place during the combustion process), allows for even heat distribution and proper airflow around the fuel, and may also collect combustion by-products. The grid may be slidably attached, detachably attached, or similar, with respect to the combustion chamber. Optionally, the at least one of the four sides has a first opening for a first door and a second opening for a second door, wherein the first door is openable for accessing the water container, and the second door is openable for accessing the grid.

[0026] Optionally, a plurality of elastomeric pads are arranged on a bottom surface of the base. For example, the plurality of elastomeric pads may be arranged at least on corners of the bottom surface. The plurality of elastomeric pads support and stabilize the hydro furnace when it is installed at a required location, for ensuring proper alignment and reducing unwanted movement or vibration during operation.

[0027] Optionally, the top part comprises inclined walls towards the first flue gas outlet. In this regard, optionally, the liquid jacket also comprises inclined walls in its portion corresponding to the inclined walls of the top part. The inclined walls of the liquid jacket enable effective upward direction of the liquid in the liquid jacket. Optionally, the inclined walls of the top part extend upwards from at least two sides of the at least three sides towards the first flue gas outlet, wherein the top part further comprises a planar portion arranged between the inclined walls, the first flue gas outlet being arranged in the planar portion. Furthermore, optionally, the second flue gas outlet is also arranged in the planar portion of the top part. A technical effect of employing the inclined walls in the top part is that angled surfaces of the inclined walls guide the flue gases upward in a manner that prevents stagnation and pressure buildup in the combustion chamber. Furthermore, the inclined walls of the top part enhance an efficiency of heat transfer from the flue gases to the liquid since they provide an increased surface area for heat exchange. Moreover, the inclined walls of the top part also discourage accumulation of combustion by-products on an internal surface of the top part of the combustion chamber.

[0028] It will be appreciated that the top part of the combustion chamber serves as an intermediate section of the hydro furnace, lying between the combustion chamber (which is a flue gas-generating section of the hydro furnace) and the inner flue gas pipe (which is a flue gas-collecting section of the hydro furnace).

[0029] Optionally, the combustion chamber is fluidically coupled to a water vapor supply. In this regard, the water vapor supply provides water vapor that is to be fed into the combustion chamber, wherein the water vapor improves the combustion efficiency through pyrolysis. Pyrolysis is a process of thermochemical decomposition of the fuel in the absence of oxygen. Pyrolysis beneficially promotes efficient conversion of the fuel into useful heat energy while minimizing emissions and improving operational efficiency of the hydro furnace. Introducing the water vapor into the combustion chamber for pyrolysis can enhance heat transfer between the flue gases and the water vapor, promote steam gasification and hydrogenation reactions, regulate temperature within the combustion chamber for optimal combustion conditions, and suppress formation of undesirable byproducts of the combustion process, thereby increasing the combustion efficiency. As an example, the water vapor may react with ash to promote steam gasification, wherein this reaction beneficially converts some mount of carbon in the ash into carbon monoxide (CO) and hydrogen (H2) gases, which are combustible and can contribute to an overall heat output of the combustion chamber. As another example, the water vapor may reduce formation of harmful emissions such as nitrogen oxides (NOx) and particulate matter, leading to a cleaner combustion process and lower environmental impact.

[0030] Optionally, the combustion chamber includes an inlet for receiving water vapor from the water vapor supply. The inlet may be arranged in a lower part of the combustion chamber. Additionally or alternatively, optionally, the water placed in the water container serves as the water vapour supply.

[0031] Optionally, the water vapor supply is an ultrasonic steam generator. In this regard, the ultrasonic steam generator produces ultrasonic water vapor, which enables pyrolysis inside the combustion chamber. Beneficially, the ultrasonic water vapor enhances heat transfer efficiency of the hydro furnace due to its fine mist-like form. The mist-like form of the ultrasonic water vapor also facilitates uniform cooling of the combustion chamber. The ultrasonic water vapor effectively absorbs heat from hot surfaces of the combustion chamber, facilitating rapid cooling and maintaining optimal operating temperatures for the combustion process. Moreover, the ultrasonic steam generator also allows for precise control over water (i.e., coolant) flow rates and distribution.

[0032] Optionally, the inner flue gas pipe diameter is from 100 mm up to 150 mm. For example, the inner flue gas pipe diameter may be from 100, 105, 110, 115, 120, 130, or 140 millimetres (mm) up to 115, 125, 135, 140, 145, or 150 mm. When the inner flue gas pipe diameter lies in the aforesaid range, optimal effectiveness of heat absorption (from the flue gases) by the liquid is achieved.

[0033] Optionally, each of the multiple pipes are arranged to cross through a centre of the inner flue gas pipe. When the hydro furnace is in operation, the multiple pipes have the liquid circulating therein. When the inner flue gas pipe is designed to have each of the multiple pipes being arranged to cross through its centre, a simple, structurally stable construction of the inner flue gas pipe is achieved, which also maximises heat transfer from the flue gases to the liquid. This enables burning of the flue gases and the oxidant in an upper portion of the combustion chamber. This improves the combustion efficiency of the hydro furnace. Optionally, the upper portion of the combustion chamber is an uppermost one-third portion of the combustion chamber.

[0034] Optionally, the multiple pipes are arranged at an angle of inclination from 20° up to 40°. For example, the angle of inclination may be from 20°, 21°, 22°, 25°, 30°, or 35° up to 24°, 28°, 32°, 36°, 38°, or 40°. Such an arrangement of the multiple pipes at the angle of inclination in the aforesaid range provides an effective design for effectively heating the liquid (by absorption of the heat from the flue gases by the liquid) and also circulating the liquid. This arrangement of the multiple pipes lies along a natural draft-like upward path of the flue gases exiting the combustion chamber through the inner flue gas pipe, so by this arrangement, the heat is transferred from the flue gases to the liquid without any special fluidic diversion of the flue gases.

[0035] Optionally, the multiple pipes are comprised of at least 10 pipes. For example, the multiple pipes may be comprised of 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 22, 24, 26, 28, 30, 35, or 40 pipes, or similar. It will be appreciated that greater the number of the multiple pipes, greater is a surface area that is provided for absorption of heat in the flue gases by the liquid circulating in the multiple pipes. Therefore, a technical effect produced by employing at least 10 pipes as the multiple pipes is that it improves an efficiency of the hydro furnace, due to the increased absorption of the heat by the liquid.

[0036] Optionally, a diameter of the multiple pipes is from 25 mm up to 50 mm. For example, the diameter of the multiple pipes may be from 25, 27.5, 30, 35, or 40 millimetres (mm) up to 32, 37, 42, 45, 48, or 50 mm. When the diameter of the multiple pipes lies in the aforesaid range, optimal effectiveness of heat absorption (from the flue gases) by the liquid is achieved. Such a diameter provides an optimal size of the multiple pipes considering the inner flue gas pipe diameter, which ensures that the multiple pipes fit well in the inner flue gas pipe and also overcome potential drawbacks with very large sized multiple pipes or very small sized multiple pipes. For example, in the very large sized multiple pipes (which, for example, have diameters greater than 50 mm), the liquid may not get heated. Alternatively, in the very small sized multiple pipes (which, for example, have diameters lesser than 25 mm), the liquid may be heated inefficiently.

[0037] Optionally, the liquid jacket comprises a hollow interior for an open liquid circulation. The hollow interior region does not contain any pipes or similar flow equipment, but rather is a continuous hollow space for enabling the open liquid circulation. The hollow interior provides ample room (i.e., space) for the liquid to freely circulate in liquid form and / or water in vapor form, for absorbing heat from the flue gases. The hollow interior enables effective circulation of the liquid without requirement of any additional equipment (such as pumps, motors, and the like) for circulating the liquid. The liquid jacket comprising the hollow interior is easy to manufacture.

[0038] Optionally, the liquid inlet is located at a lower part of the liquid jacket and the liquid outlet is located at an upper part of the liquid jacket. In other words, a height of the liquid inlet is lesser than a height of the liquid outlet. The liquid enters the liquid jacket through the liquid inlet and exits the liquid jacket through the liquid outlet. The liquid exiting the liquid jacket is hot liquid, as it absorbs the heat from the flue gases while circulating in the liquid jacket. Optionally, the lower part of the liquid jacket surrounds a lower portion of the combustion chamber. For example, the liquid inlet may be located in a lower portion of one of the four sides of the combustion chamber. Optionally, the upper part of the liquid jacket surrounds an upper portion of the inner flue gas pipe. For example, the liquid outlet may be located in proximity of the second end of the inner flue gas pipe. A technical effect of providing the liquid outlet at the upper part of the liquid jacket is that it allows the liquid to exit the liquid jacket only upon circulating through a long fluidic path in the liquid jacket so that the liquid effectively absorbs maximum heat from the flue gases during such circulation. Providing the liquid inlet at the lower part of the liquid jacket enables in maximizing a length of the fluidic path along which the liquid circulates.

[0039] Optionally, the liquid jacket further comprises an additional liquid inlet. Water vapour may also be provided into the liquid jacket via the additional water inlet, if required, for efficient heat absorption from the flue gases. The additional water inlet may be arranged higher than the liquid inlet. Optionally, a length of the liquid inlet may be greater than a length of the additional water inlet. The length of the liquid inlet may, for example, be 147 millimeters, while the length of the additional water inlet may, for example, be 47 millimetres.

[0040] Optionally, the liquid outlet makes an obtuse angle with an outer surface of the liquid jacket. As an example, the liquid outlet may be arranged at 94.8 degrees with respect to the outer surface of the liquid jacket. Said outer surface of the liquid jacket may be perpendicular to the base of the combustion chamber. Optionally, a length of the liquid outlet lies in a range of 100 millimetres to 350 millimetres. For example, the length of the liquid outlet may be 229 millimetres, of which 141.1 millimetres may lie inside the hydro furnace and 87.9 millimetres may extend out of the hydro furnace.

[0041] Optionally, the hydro furnace further comprises a water storage unit below the combustion chamber. The water storage unit can be used to store the water which is to be circulated as the liquid in the water jacket, when the hydro furnace is in operation. The water storage unit beneficially provides an uninterrupted supply of the water for absorbing the heat from the flue gases during the combustion process. The water storage unit can optionally also be employed to provide water vapor through the water vapor supply coupled to the combustion chamber, for pyrolysis.

[0042] Optionally, the water vapor supply and / or the water storage unit are supplied with water via a supply pipe. The supply pipe will supply water to the water vapor supply and / or the water storage unit.

[0043] Optionally, the hydro furnace further comprises a water chamber arranged in the combustion chamber and fluidically coupled to the liquid jacket. The water chamber is fluidically coupled to the liquid jacket at two or more ends. The water chamber may comprise a container portion and two or more pipes connecting the container portion to the liquid jacket. When the hydro furnace is in use, the liquid being a water, circulates through the water chamber for increasing heat absorption from the flue gases, which in turn increases the efficiency of the hydro furnace. The container portion of the water chamber may be implemented by the water container that optionally, in use, is arranged on the base of the combustion chamber.DETAILED DESCRIPTION OF THE DRAWINGS

[0044] Referring to FIGs. 1A, 1B, 1C, 1D, and 1E (hereinafter referred as 1A-E for simplicity only), FIGs. 1A, 1B, and 1C illustrate perspective views of a hydro furnace 100, FIG. 1D illustrates an exploded perspective view of a portion of the hydro furnace 100, while FIG. 1E illustrates an exploded view of the hydro furnace 100, in accordance with an embodiment of the present invention. In FIGs. 1A-E, the hydro furnace 100 comprises a combustion chamber 102, an inner flue gas pipe 104, a liquid jacket 106, and a bypass flue gas pipe 108. It will be appreciated that owing to a design of the hydro furnace 100, some constituent elements of the hydro furnace 100 may be invisible in one or more views of FIGs 1A-E.

[0045] Moreover, in FIGs. 1A-E: The combustion chamber 102 comprises a first flue gas outlet 110 and a second flue gas outlet 112.

[0046] The inner flue gas pipe 104 has a first end 114 and a second end 116, the first end 114 being connected to the first flue gas outlet 110. The inner flue gas pipe 104 further comprises multiple pipes (depicted as pipes 118a, 118b, 118c, 118d, and 118f, referred hereinafter collectively as 118a-f). Each of the multiple pipes 118a-f comprises a third end 120 and a fourth end 122. For sake of simplicity, the third end 120 and the fourth end 122 are labelled only in FIG. 1A, and only for the pipes 118c and 118d. Each of the multiple pipes 118a-f is arranged to cross through the inner flue gas pipe 104.

[0047] The liquid jacket 106 surrounds at least partially the combustion chamber 102 and the inner flue gas pipe 104. The liquid jacket 106 comprises a liquid inlet 124 and a liquid outlet 126, and wherein the third end 120 and the fourth end 122 of the multiple pipes 118a-f are connected to the liquid jacket 106. Liquid circulating through the liquid jacket 106 when the hydro furnace 100 is in operation, is depicted via dotted arrows.

[0048] The bypass flue gas pipe 108 has a fifth end 128 and a sixth end 130, the fifth end 128 being connected to the second flue gas outlet 112.

[0049] In FIG. 1D, the portion of the hydro furnace 100 whose exploded perspective view is shown, is the liquid jacket 106 surrounding the combustion chamber 102. The combustion chamber 102 is shown to comprise a base 132, four sides (of which only two sides 134a and 134b are visible in the perspective view of FIG. 1D, and sides 134c and 134d are visible in FIG. 1E along with the two sides 134a and 134b) and a top part 136 opposite to the base 132. The top part 136 comprises the first flue gas outlet 110 and the second flue gas outlet 112. The liquid jacket 106 surrounds the combustion chamber 102 from at least three sides and at least partially from the top part 136.

[0050] As shown, the top part 136 may comprise inclined walls (depicted as inclined walls 138 and 140) towards the first flue gas outlet 110. The top part 136 may also comprise a planar part 139 arranged between the inclined walls 138 and 140. At least one of the four sides, such as the side 134a may have a first opening for a first door D1 and a second opening for a second door D2. The first door D1 may be openable for accessing a water container 142 into which water is placed when the hydro furnace 100 is in operation. The water container 142 may be used as a water vapor supply. The second door D2 may be openable for accessing a grid 143 (shown in FIGs. 1A and 1B) upon which fuel is placed when the hydro furnace 100 is in operation. There may be arranged a plurality of elastomeric pads 144 on a bottom surface 146 of the base 132. The bottom surface 146 and an exemplary arrangement plurality of elastomeric pads 144 is visible in the perspective view of FIG. 1C.

[0051] Furthermore, as shown in FIGs. 1A-E, each of the multiple pipes may be arranged to cross through a centre 148 (shown in FIG. 1E) of the inner flue gas pipe 104. The liquid inlet 124 may be located at a lower part of the liquid jacket 106 and the liquid outlet 126 may be located at an upper part of the liquid jacket 106. The liquid jacket 106 may comprise a hollow interior 149 for an open liquid circulation. Sub-parts 106a, 106b, 106c, and 106d (visible in FIG. 1E) of the liquid jacket 106, when arranged with respect to the combustion chamber 102 and the inner flue gas pipe 104, form the hollow interior 149. The liquid jacket 106 may further comprise an additional water inlet 150.

[0052] It may be understood by a person skilled in the art that the FIGs. 1A, 1B, 1C, 1D, and 1E include simplified representations of the hydro furnace 100 and its components for sake of clarity, which should not unduly limit the scope of the claims herein. The person skilled in the art will recognize many variations, alternatives, and modifications of embodiments of the present invention. For example, the multiple pipes 118a-f may be comprised of at least 10 pipes. In another example, multiple pipes 118a-f may be oriented and / or arranged differently than as shown in FIGs. 1A-E.

[0053] Referring to FIGs. 2A, 2B, 2C, and 2D (hereinafter referred as 2A-D for simplicity only), FIGs. 2A and 2B illustrate perspective views of a combustion chamber 202 and an inner flue gas pipe 204 of a hydro furnace 200, FIG. 2C illustrates a back view of the hydro furnace 200 wherein a water jacket 234 surrounds at least partially the combustion chamber 202 and the inner flue gas pipe 204, while FIG. 2D illustrates an exploded view of the combustion chamber 202 and the inner flue gas pipe 204, in accordance with an embodiment of the present invention.

[0054] It will be appreciated that owing to a design of the hydro furnace 200, some constituent elements of the hydro furnace 200 may be invisible in one or more views of FIGs 2A-D. Notably, FIGs. 2A, 2B, and 2D represent internal structures of the hydro-furnace 200, while FIG. 2C represents both the internal structures as well as an external structure of the hydro-furnace 200.

[0055] In FIGs. 2A-D: Three sides 206a, 206b and 206c of the combustion chamber 202 are shown. A base 208 and a top part 210 of the combustion chamber 202 is also shown, wherein the top part 210 comprises a first flue gas outlet 212 and a second flue gas outlet 214. Moreover, as shown, the top part 210 may comprise inclined walls (depicted as inclined walls 216 and 218) towards the first flue gas outlet 212. The top part 210 may also comprise a planar part 217 arranged between the inclined walls 216 and 218.

[0056] The inner flue gas pipe 204 has a first end 222 and a second end 224, the first end 222 being connected to the first flue gas outlet 212. The inner flue gas pipe 204 further comprises multiple pipes (depicted for example as pipes 226), each of the multiple pipes 226 comprising a third end 228 and a fourth end 230, and wherein each of the multiple pipes 226 is arranged to cross through the inner flue gas pipe 204. Each of the multiple pipes 226 is arranged to arranged to cross through a centre 229 of the inner flue gas pipe 204. The multiple pipes 226 are arranged at an angle of inclination from 20° up to 40°. The multiple pipes 226 are comprised of at least 10 pipes.

[0057] The hydro furnace 200 may further comprise a water chamber 232 (shown in FIGs. 2C and 2D) arranged in the combustion chamber 202 and fluidically coupled to the water jacket 234 of the hydro furnace 200. The water chamber 232 is fluidically coupled to the water jacket 234 at two or more ends (depicted as ends 236a, 236b, and 236c). The water jacket 234 comprises a water inlet 220 and a water outlet 240. The water jacket 234 may also comprise an additional water inlet 242 in case the liquid is water. The liquid outlet 240 may make an obtuse angle 244 with an outer surface of the liquid jacket 234.

[0058] The hydro furnace 200 may further comprise a supply pipe 250 to supply water to a water vapor supply or to a water storage unit.

[0059] FIGs. 2A, 2B, 2C and 2D are merely examples, which should not unduly limit the scope of the claims herein. A person skilled in the art will recognize many variations, alternatives, and modifications of embodiments of the present invention.

Claims

1. A hydro furnace (100, 200) comprising: a combustion chamber (102, 202) comprising a first flue gas outlet (110, 212) and a second flue gas outlet (112, 214), an inner flue gas pipe (104, 204) having a first end (114, 222) and a second end (116, 224), the first end being connected to the first flue gas outlet, the inner flue gas pipe further comprising multiple pipes (118a, 118b, 118c, 118d, 118e, 118f, 226), each of the multiple pipes comprising a third end (120, 228) and a fourth end (122, 230), and wherein each of the multiple pipes is arranged to cross through the inner flue gas pipe; a liquid jacket (106, 234) surrounding at least partially the combustion chamber and the inner flue gas pipe, the liquid jacket comprising a liquid inlet (124, 220) and a liquid outlet (126, 240), and wherein the third end and the fourth end of the multiple pipes are connected to the liquid jacket; and a bypass flue gas pipe (108) having a fifth end (128) and a sixth end (130), the fifth end being connected to the second flue gas outlet.

2. A hydro furnace (100, 200) according to claim 1, wherein the combustion chamber (102, 202) comprises a base (132, 208), four sides (134a, 134b, 134c, 134d, 206a, 206b, 206c) and a top part (136, 210) opposite to the base, wherein the top part comprises the first flue gas outlet (110, 212) and the second flue gas outlet (112, 214), and wherein the liquid jacket (106, 234) surrounds the combustion chamber from at least three sides and at least partially from the top part.

3. A hydro furnace (100, 200) according to claims 1 or 2, wherein each of the multiple pipes (118a, 118b, 118c, 118d, 118e, 118f, 226) are arranged to cross through a centre (148, 229) of the inner flue gas pipe (104, 204).

4. A hydro furnace (100, 200) according to any of the preceding claims, wherein the liquid inlet (124, 220) is located at a lower part of the liquid jacket (106, 234) and the liquid outlet (126, 240) is located at an upper part of the liquid jacket.

5. A hydro furnace (100, 200) according to any of the preceding claims, wherein the multiple pipes (118a, 118b, 118c, 118d, 118e, 118f, 226) are arranged at an angle of inclination from 20° up to 40°.

6. A hydro furnace (100, 200) according to any of the preceding claims, wherein the multiple pipes (118a, 118b, 118c, 118d, 118e, 118f, 226) are comprised of at least 10 pipes.

7. A hydro furnace (100, 200) according to any of the preceding claims, wherein a diameter of the multiple pipes (118a, 118b, 118c, 118d, 118e, 118f, 226) is from 25 mm up to 50 mm.

8. A hydro furnace (100, 200) according to any of the preceding claims, wherein the inner flue gas pipe diameter is from 100 mm up to 150 mm.

9. A hydro furnace (100, 200) according to any of the preceding claims, wherein the combustion chamber (102, 202) is fluidically coupled to a water vapor supply.

10. A hydro furnace (100, 200) according to any of the preceding claims, further comprising a water storage unit below the combustion chamber (102, 202).

11. A hydro furnace (100, 200) according to claim 9, wherein the water vapor supply is an ultrasonic steam generator.

12. A hydro furnace (100, 200) according to any of the preceding claims, wherein the liquid jacket (106, 234) comprises a hollow interior (149) for an open liquid circulation.

13. A hydro furnace (100, 200) according to any of claims 2-12, wherein the top part (136) comprises inclined walls (138, 140, 216, 218) towards the first flue gas outlet.

14. A hydro furnace (100, 200) according to any of the preceding claims, wherein the liquid is water.