Spiral heat exchange tube type low-nitrogen condensation water heater

Abstract

The utility model discloses a spiral heat exchange tube type low-nitrogen condensation water heater which comprises a shell, a combustion module and a spiral heat exchange tube set, a top cover is arranged at the top of the shell, the combustion module comprises a gas valve, an air filter, a venturi, a combustion cylinder and a combustion chamber, the combustion chamber is cylindrical, and the combustion chamber and the top cover form a sealing structure. A first gap is formed between the inner side wall of the combustion chamber and the combustion cylinder, a second gap is formed between the inner bottom wall of the combustion chamber and the combustion cylinder, and the width of the first gap is smaller than that of the second gap. According to the water heater, the cylindrical sealed combustion chamber is formed by the water heater and the top cover of the shell, and the left-right and up-down gaps between the combustion chamber and the combustion cylinder are improved, so that more spiral heat exchange tube group structures with larger inner diameters can be arranged, high-temperature flue gas can be buffered in the combustion chamber, and the heat exchange efficiency is improved. The water temperature of the upper layer of the water storage cavity can be increased under the condition that the tempering phenomenon can be avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of water heaters, in particular to a spiral heat exchange tube type low-nitrogen condensing water heater. Background Art

[0002] Gas water heaters use gas as energy and heat water through the heat generated by gas combustion to make the water temperature meet the requirements of life, heating, production process, etc. Low nitrogen condensing water heaters use gas and air to mix evenly in advance to form a gas-air mixture, and then ignite and burn it to make its flue gas emit NO X Low, achieving the effect of low nitrogen emissions. At present, most low-nitrogen condensing water heaters on the market adopt a volumetric structure, with a gas water heater with a hot water storage container inside as a part of the water heater. The principle is: a mixture of gas and air is sprayed from the top of the water heater, enters the combustion cylinder, ignites and burns in the combustion chamber, and then the high-temperature flue gas flows out along the heat exchanger and exchanges heat with cold water to heat the cold water. Finally, the flue gas after heat exchange flows out from the bottom, that is, the flue gas flows from top to bottom, achieving a better heat exchange effect.

[0003] In the prior art, the bottom / top of the combustion chamber of most water heaters adopts a semicircular or semi-elliptical structure. For example, CN218820983U discloses a volumetric gas water heater, in which both ends of the combustion chamber adopt a semicircular structure. Combined with the structure of the heat exchange component of the small diameter pipe, the high-temperature flue gas can flow out quickly and achieve a better heat exchange effect. However, due to the short residence time of the high-temperature flue gas in the combustion chamber, it is easy to cause the water temperature on the upper part of the heat storage tank to be insufficient and fail to meet the water temperature requirements of the user. In addition, the small diameter of the heat exchange pipe is not conducive to installation or maintenance. Utility Model Content

[0004] In order to overcome the deficiencies of the prior art, the utility model provides a spiral heat exchange tube type low nitrogen condensing water heater to solve the above-mentioned traditional problems.

[0005] The utility model is implemented by the following technical solutions:

[0006] A spiral heat exchange tube type low-nitrogen condensing water boiler, comprising an outer shell, a combustion module installed on the top of the outer shell and a spiral heat exchange tube group connected to the combustion module, the top of the outer shell is provided with a top cover, the combustion module comprises a gas valve, an air filter, a venturi connected to the gas valve and the air filter respectively, a combustion barrel connected to the venturi and a combustion chamber, the combustion barrel is placed in the combustion chamber, the combustion chamber is arranged in the water storage cavity, the combustion chamber is cylindrical and the combustion chamber and the top cover form a sealing structure, a first gap is provided between the inner side wall of the combustion chamber and the combustion barrel, a second gap is provided between the inner bottom wall of the combustion chamber and the combustion barrel, the width of the first gap is smaller than the width of the second gap; the spiral heat exchange tube group is installed at the bottom of the combustion chamber.

[0007] Preferably, the width of the first gap is 0.7-0.9 of the width of the second gap.

[0008] Preferably, a third gap is provided between the outer side wall of the combustion chamber and the outer shell, and the width of the third gap is smaller than the width of the first gap.

[0009] Preferably, the width of the third gap is 0.7-0.9 of the width of the first gap.

[0010] Preferably, the outer shell is cylindrical, and a smoke collecting box connected to the spiral heat exchange tube group is also provided at the bottom of the outer shell, the smoke collecting box includes a smoke collecting part and a smoke exhaust part, the smoke collecting part is provided at the bottom of the outer shell, the smoke exhaust part is provided on the outside of the outer shell, a vertically arranged smoke exhaust pipe is provided on the side of the smoke exhaust part away from the smoke collecting part, and a condensate discharge port is also provided on one side of the smoke exhaust part.

[0011] Preferably, the diameter of the smoke exhaust pipe is larger than the diameter of the spiral heat exchange tube in the spiral heat exchange tube group.

[0012] Preferably, the diameter of the smoke exhaust pipe is 2-3.5 times the diameter of the spiral heat exchange tube in the spiral heat exchange tube group.

[0013] Preferably, the spiral heat exchange tube group is formed by a plurality of heat exchange tubes spiraled from top to bottom, and the heat exchange tubes include an input tube, a spiral tube and an output tube connected in sequence, and the input tube is arranged vertically to the combustion chamber.

[0014] Preferably, the combustion tube is a metal fiber burner.

[0015] Preferably, a heat insulating sealing plate is provided at the connection between the combustion tube and the venturi, and the heat insulating sealing plate is an aluminum silicate plate.

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] The spiral heat exchange tube type low-nitrogen condensing water heater of the utility model forms a cylindrical sealed combustion chamber with the top cover of the outer shell, and improves the left and right and up and down gaps between the combustion chamber and the combustion tube, so that more spiral heat exchange tube groups with larger inner diameters can be arranged, so that high-temperature flue gas can be buffered in the combustion chamber, and the water temperature of the upper layer of the water storage chamber can be increased while avoiding the occurrence of flashback. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a three-dimensional structural diagram of the spiral heat exchange tube type low nitrogen condensing water heater of the utility model;

[0019] Figure 2 for Figure 1 A side view of a spiral heat exchange tube type low nitrogen condensing water heater is shown;

[0020] Figure 3 for Figure 1 A cross-sectional view of a spiral heat exchange tube type low nitrogen condensing water heater is shown.

[0021] In the figure: 10, outer shell; 11, smoke collection box; 12, smoke exhaust pipe; 13, condensate discharge port; 20, combustion module; 21, gas valve; 22, air filter; 23, Venturi; 24, combustion tube; 25, combustion chamber; 30, spiral heat exchange tube group. DETAILED DESCRIPTION

[0022] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0023] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0024] In the description of the present utility model, it is necessary to understand that when an element is considered to be "connected" to another element, it may be directly connected to another element or there may be intermediate elements at the same time. On the contrary, when an element is said to be "directly" connected to another element, there are no intermediate elements.

[0025] See also Figure 1-Figure 3 , which is a spiral heat exchange tube type low-nitrogen condensing water heater of a preferred embodiment of the utility model, is used to use gas as energy, heat water through the heat generated by gas combustion, and provide hot water for users. Specifically, the spiral heat exchange tube type low-nitrogen condensing water heater includes a shell 10 with a water storage cavity, a combustion module 20 installed on the top of the shell 10, a spiral heat exchange tube group 30 connected to the combustion module 20, and a control system.

[0026] The outer shell 10 is the water storage body of the entire water heater. The outer shell 10 is roughly cylindrical, that is, the outer shell 10 consists of a main body, a top cover arranged on the top of the main body and a bottom cover arranged at the bottom of the main body. The top cover and the bottom cover are both flat plates, which are convenient for installation and installation of other accessories. The main body, the top cover and the bottom cover form the water storage cavity, wherein the thickness of the top cover is greater than the thickness of the bottom cover, which is convenient for fixing the combustion module 20 and the spiral heat exchange tube group 30. In this embodiment, a smoke collecting box 11 connected to the spiral heat exchange tube group 30 is also provided at the bottom of the shell 10. The smoke collecting box 11 includes a smoke collecting part and a smoke exhaust part. The smoke collecting part is provided at the bottom of the shell 10, and the smoke exhaust part is provided on the outside of the shell 10. A vertically arranged smoke exhaust pipe 12 is provided on the side of the smoke exhaust part away from the smoke collecting part. A condensate discharge port 13 is also provided on one side of the smoke exhaust part for discharging condensate in the smoke collecting box 11. In one embodiment, the diameter of the smoke exhaust pipe 12 is greater than the diameter of the spiral heat exchange tube in the spiral heat exchange tube group 30. Optionally, the diameter of the smoke exhaust pipe 12 is 2-3.5 of the diameter of the spiral heat exchange tube in the spiral heat exchange tube group 30. Specifically, the diameter of the smoke exhaust pipe 12 is 270 mm, and the diameter of the condensate discharge port 13 is 40 mm. In other embodiments, control valves are provided on the smoke exhaust pipe 12 and the condensate discharge port 13 to control the discharge of smoke / condensate. The side of the housing 10 is provided with a cold water inlet and a hot water outlet, the cold water inlet is provided at the lower end of the housing 10, and the hot water outlet is provided at the upper end of the housing 10, specifically, the hot water outlet is placed above the spiral heat exchange tube group 30. The inner layer of the top cover can be coated or paved with heat insulation, high temperature resistant materials, corrosion resistant materials, etc., to insulate it, resist high temperature, resist corrosion, and improve the durability of the equipment.

[0027] like Figure 1 and Figure 2As shown, the combustion module 20 includes a gas valve 21, an air filter 22, a venturi 23 connected to the gas valve 21 and the air filter 22 respectively, a combustion tube 24 connected to the venturi 23, an ignition electrode, an ion probe and a combustion chamber 25. The gas valve 21 is used to adjust the gas intake, the air filter 22 is used to adjust the air intake, the venturi 23 is used to pre-evenly mix the gas and air, and the combustion tube 24 is a metal fiber burner, the head of which is made of extremely fine metal fibers, which has the effect of full combustion and low nitrogen oxide emission. The ignition electrode is used to ignite the combustion tube 24, and the ion probe is used to detect the flame on the surface of the combustion tube 24. In this embodiment, the combustion tube 24 is penetrated through the top cover of the shell, and the connection between the combustion tube 24 and the venturi 23 is provided with a heat insulation sealing plate, which is but not limited to an aluminum silicate plate. Through the action of the aluminum silicate plate, the heat transfer efficiency between the combustion tube 24 and the venturi 23 is reduced to avoid heat loss. In other embodiments, the combustion module 20 also includes detection equipment such as a water pressure relief valve, a magnesium rod, a water temperature controller, and a water level electrode for detecting control parameters in the shell so as to make corresponding adjustments.

[0028] like Figure 3 As shown, the combustion tube 24 is placed in the combustion chamber 25, and the combustion chamber 25 is arranged in the water storage cavity. When the high-temperature flue gas generated by the combustion of the combustion tube 24 is heated, the heat is transferred to the water in the water storage cavity through the combustion chamber 25 and the spiral heat exchange tube group 30. The combustion chamber 25 also has the function of buffering the high-temperature flue gas and guiding the high-temperature flue gas into the spiral heat exchange tube group 30 to avoid the high-temperature flue gas from backflowing into the combustion tube 24 and causing the phenomenon of flashback. Specifically, the combustion chamber 25 is roughly cylindrical, and the bottom of the combustion chamber 25 is flat. , which is convenient for the layout of each pipe of the spiral heat exchange tube group 30, and is also convenient for the layout of heat exchange tubes with larger diameters; the top of the combustion chamber 25 can be open or closed. If it is open, the combustion chamber 25 and the top cover of the outer shell 10 form a sealed structure, wherein a first gap is provided between the inner wall of the combustion chamber 25 and the combustion tube 24, and a second gap is provided between the inner bottom wall of the combustion chamber 25 and the combustion tube 24. The width of the first gap is smaller than the width of the second gap, so that the high-temperature flue gas can be buffered in the combustion chamber 25 to increase the water temperature of the upper layer of the water storage chamber. In this embodiment, the width of the first gap is 0.7-0.9 of the width of the second gap. Preferably, the width of the first gap is 0.85 of the width of the second gap. In other embodiments, a third gap is provided between the outer wall of the combustion chamber 25 and the outer shell 10, and the width of the third gap is smaller than the width of the first gap, so that the water temperature of the upper layer of the water storage chamber can reach a higher temperature. Optionally, the width of the third gap is 0.7-0.9 of the width of the first gap, and preferably, the width of the third gap is 0.75 of the width of the first gap. In this embodiment, the combustion chamber 25 is made of high temperature resistant material.

[0029] like Figure 3 As shown, the spiral heat exchange tube group 30 is installed at the bottom of the combustion chamber 25, and is used to connect the combustion chamber 25 with the smoke collecting box 11 at the bottom of the outer shell 10. The spiral heat exchange tube group 30 is formed by a plurality of heat exchange tubes spiraled from top to bottom, wherein the heat exchange tubes include an input tube, a spiral tube and an output tube connected in sequence, the input tube is vertically arranged to the combustion chamber 25, so as to facilitate the introduction of flue gas, the spiral tubes have the same spiral circumference and spiral in the same direction from top to bottom to form an upper and lower stacked structure, with spiral gaps between the spiral tubes, the output tube is connected to the smoke collecting box 11, and is perpendicular to the smoke collecting box 11, so as to facilitate the outflow of flue gas. It can be understood that the spiral heat exchange tube group 30 contains multiple heat exchange tubes, and each heat exchange tube is evenly distributed and arranged on the combustion chamber 25. For example, the input tube is arranged along the same circumference of the bottom of the combustion chamber 25, and then spirals in the same direction. Because the circumference is equal and the angle is the same, that is, the walking trajectory is also similar, so that the spiral tubes are stacked up and down. At the same time, because there is a spiral gap between the spiral tubes, that is, a spring-like structure, a buffer for water flow, smoke, etc. can be formed. The spacing is designed according to the specific model, which will not be repeated here. The number of spiral heat exchange tube groups 30 is 2 groups, and the diameter of the inner spiral heat exchange tube group 30 and the outer spiral heat exchange tube group 30 can be the same or different. In this embodiment, the diameter of the inner and outer spiral heat exchange tube groups 30 is DN80. In addition to the above-mentioned restrictions, the number of spiral heat exchange tube groups 30 can also be 2 groups, 4 groups, 5 groups, 6 groups, etc., designed according to the model and heat exchange efficiency of the water heater, which will not be repeated here.

[0030] The control system is used to control the entire device. The control system is electrically connected to the water pressure relief valve, magnesium rod, water temperature controller, water level electrode, gas valve 21, ignition electrode, ion probe and other equipment to control the start and stop of the equipment after receiving the signal.

[0031] The working principle of the water heater is: utilizing the principle that water density decreases as temperature rises, the higher the water temperature, the more the hot water flows upward, so that the water in the water storage chamber flows upward and the water temperature increases, ensuring that the output water is hotter, and the flue gas flows downward, continuously transferring high-temperature heat from top to bottom to the water in the water storage chamber, so that the water in the upper part is in a heated state and the water in the lower part is in a preheated state, so as to continuously and repeatedly utilize the heat of the flue gas, thereby improving the thermal efficiency of the water heater.

[0032] The above-mentioned spiral heat exchange tube type low-nitrogen condensing water heater forms a cylindrical sealed combustion chamber 25 with the top cover of the outer shell 10, and improves the left and right, up and down gaps between the combustion chamber 25 and the combustion tube 24. It is possible to arrange more spiral heat exchange tube groups 30 with larger inner diameters, so that high-temperature flue gas can be buffered in the combustion chamber 25, thereby increasing the water temperature in the upper layer of the water storage chamber while avoiding the occurrence of flashback.

[0033] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0034] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A spiral heat exchange tube type low nitrogen condensing water heater, characterized in that: It includes an outer shell, a combustion module installed on the top of the outer shell and a spiral heat exchange tube group connected to the combustion module. The top of the outer shell is provided with a top cover. The combustion module includes a gas valve, an air filter, a venturi connected to the gas valve and the air filter respectively, a combustion tube connected to the venturi and a combustion chamber. The combustion tube is placed in the combustion chamber, and the combustion chamber is arranged in the water storage cavity of the outer shell. The combustion chamber is cylindrical and forms a sealing structure with the top cover. A first gap is provided between the inner side wall of the combustion chamber and the combustion tube, and a second gap is provided between the inner bottom wall of the combustion chamber and the combustion tube. The width of the first gap is smaller than the width of the second gap. The spiral heat exchange tube group is installed at the bottom of the combustion chamber.

2. The spiral heat exchange tube type low nitrogen condensing water heater according to claim 1, characterized in that: The width of the first gap is 0.7-0.9 of the width of the second gap.

3. The spiral heat exchange tube type low nitrogen condensing water heater according to claim 1, characterized in that: A third gap is provided between the outer side wall of the combustion chamber and the outer shell, and a width of the third gap is smaller than a width of the first gap.

4. The spiral heat exchange tube type low nitrogen condensing water heater according to claim 3, characterized in that: The width of the third gap is 0.7-0.9 of the width of the first gap.

5. The spiral heat exchange tube type low nitrogen condensing water heater according to claim 1, characterized in that: The outer shell is cylindrical, and a smoke collecting box connected to the spiral heat exchange tube group is also provided at the bottom of the outer shell. The smoke collecting box includes a smoke collecting part and a smoke exhaust part. The smoke collecting part is provided at the bottom of the outer shell, and the smoke exhaust part is provided at the outside of the outer shell. A vertically arranged smoke exhaust pipe is provided on the side of the smoke exhaust part away from the smoke collecting part, and a condensed water discharge port is also provided on one side of the smoke exhaust part.

6. The spiral heat exchange tube type low nitrogen condensing water heater according to claim 5, characterized in that: The diameter of the smoke exhaust pipe is larger than the diameter of the spiral heat exchange tube in the spiral heat exchange tube group.

7. The spiral heat exchange tube type low nitrogen condensing water heater according to claim 6, characterized in that: The diameter of the smoke exhaust pipe is 2-3.5 of the diameter of the spiral heat exchange tube in the spiral heat exchange tube group.

8. The spiral heat exchange tube type low nitrogen condensing water heater according to claim 1, characterized in that: The spiral heat exchange tube group is formed by a plurality of heat exchange tubes spiraling from top to bottom. The heat exchange tubes include an input tube, a spiral tube and an output tube connected in sequence. The input tube is vertically arranged to the combustion chamber.

9. The spiral heat exchange tube type low nitrogen condensing water heater according to claim 1, characterized in that: The combustion tube is a metal fiber burner.

10. The spiral heat exchange tube type low nitrogen condensing water heater according to claim 1, characterized in that: A heat-insulating sealing plate is provided at the connection between the combustion tube and the venturi, and the heat-insulating sealing plate is an aluminum silicate plate.

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