An energy-saving and environmentally friendly horizontal three-pass boiler structure

Abstract

The invention discloses an energy-saving and environmentally friendly horizontal three-pass boiler structure in the field of boiler technology, comprising a horizontally arranged boiler shell, a burner is arranged at the lower side of the front end of the boiler shell, a condenser is arranged at the lower side of the rear end of the boiler shell, a heat exchanger is arranged at the upper side of the rear end of the boiler shell, a heat exchange tube of the heat exchanger extends into the upper side of the inner cavity of the boiler shell, a furnace and a backfire chamber are arranged at the lower side of the inner cavity of the boiler shell, the front end of the furnace is connected to the burner, the rear end of the furnace is connected to the backfire chamber, a water cavity is formed between the outer sides of the furnace, the backfire chamber and the inner wall of the boiler shell, the rear end of the backfire chamber is connected to the smoke inlet of the condenser, the water outlet of the condenser is connected to the water inlet of the heat exchanger, a smoke partition is arranged in the middle of the backfire chamber, a smoke passage is left between the smoke partition and the left inner wall of the backfire chamber, a light tube heat exchange tube is arranged at the front side of the smoke partition, and a fin heat exchange tube is arranged at the rear side, and the light tube heat exchange tube and the fin heat exchange tube are arranged vertically and the inside is connected to the water cavity. The invention has the advantages of simple structure, convenient manufacturing, wide application range, high safety, energy saving and environmental protection, etc.

Description

Technical Field

[0001] The invention relates to a boiler, in particular to an energy-saving and environment-friendly horizontal three-pass boiler structure. Background Art

[0002] With the development of the national economy and the improvement of people's awareness of energy conservation and environmental protection, in order to improve the living and investment environment and meet the requirements of environmental protection and energy conservation, it is necessary to further improve the thermal efficiency of boilers and reduce the NO in flue gas. X 、SO X To meet this demand, the structural design of boilers has become increasingly complex, resulting in rising costs, manufacturing difficulties, and inconvenient maintenance. Summary of the invention

[0003] The purpose of the present invention is to provide an energy-saving and environmentally friendly horizontal three-pass boiler structure which has a simpler structure, lower cost and can maintain higher thermal efficiency.

[0004] The objective of the present invention is achieved in this way: an energy-saving and environmentally friendly horizontal three-pass boiler structure comprises a horizontally arranged boiler shell, a burner is arranged on the lower side of the front end of the boiler shell, a condenser is arranged on the lower side of the rear end of the boiler shell, a heat exchanger is arranged on the upper side of the rear end of the boiler shell, the heat exchange pipe of the heat exchanger extends into the upper side of the inner cavity of the boiler shell, a furnace gallbladder and a reburning chamber are arranged on the lower side of the inner cavity of the boiler shell, the front end of the furnace gallbladder is connected to the burner, the rear end of the furnace gallbladder is communicated with the reburning chamber, a water cavity is formed between the outer sides of the furnace gallbladder and the reburning chamber and the inner wall of the boiler shell, a smoke outlet is arranged at the rear end of the reburning chamber, the smoke outlet is communicated with the smoke inlet of the condenser, the water outlet of the condenser is communicated with the water inlet of the heat exchanger, a smoke partition wall is arranged in the middle of the reburning chamber, a smoke passage is left between the smoke partition wall and the left inner wall of the reburning chamber, a light tube heat exchange pipe is arranged on the front side of the smoke partition wall, a finned heat exchange pipe is arranged on the rear side of the smoke partition wall, the light tube heat exchange pipe and the finned heat exchange pipe are arranged vertically and are internally communicated with the water cavity.

[0005] In the energy-saving and environmentally friendly horizontal three-pass boiler structure of the present invention, the burner burns in the furnace to generate high-temperature flue gas, which is radiated and horizontally flushed through the front section of the regenerative chamber arranged with light tube heat exchange tubes in the second return, and then turns to the third return through the flue gas partition wall in the regenerative chamber to horizontally flush the convection tube bundle arranged with finned heat exchange tubes. After sufficient heat exchange, it is further heat exchanged in the tail condenser and discharged to the chimney, and finally the exhaust temperature of the boiler can be reduced to less than 80°C, so that the body design thermal efficiency is as high as 96%. In addition, the energy-saving and environmentally friendly horizontal three-pass boiler structure of the present invention also has the advantages of simple structure, convenient manufacturing, wide application range, strong pressure bearing capacity, high safety, energy saving and environmental protection.

[0006] As a further improvement of the present invention, the reburning chamber is in the shape of a long cylinder, including a front end plate, a rear end plate, an upper tube plate, a lower tube plate, a left arc plate, and a right arc plate. The upper and lower ends of the flue gas partition wall are respectively welded and fixed to the upper tube plate and the lower tube plate, and the right side of the flue gas partition wall is welded and fixed to the right arc plate. The two ends of the light tube heat exchange tube and the fin heat exchange tube are respectively connected to the upper tube plate and the lower tube plate, and the curvature of the left arc plate is greater than that of the right arc plate. This structure reasonably arranges a large number of heat exchange tube bundles in a small space, increases the radiation and convection heating surface, greatly improves the heat transfer efficiency of the boiler, and reduces the flue gas resistance (boiler back pressure), so that the power consumption of the burner is smaller and more energy-saving.

[0007] As a further improvement of the present invention, there is a gap between the rear end plate and the rear end wall of the pot shell, so that the rear end plate and the rear end wall of the pot shell are connected to the water cavity, avoiding excessive temperature of the rear end wall of the pot shell and preventing heat loss.

[0008] As a further improvement of the present invention, the heat exchanger adopts a U-tube heat exchanger, which further simplifies the boiler structure and facilitates the disassembly, assembly and maintenance of the heat exchanger, thereby reducing the manufacturing and maintenance costs.

[0009] As a further improvement of the present invention, a plurality of groups of condenser heat exchange tubes are provided in the condenser, and the plurality of groups of condenser heat exchange tubes are arranged in series, so that the cold fluid flows in the condenser heat exchange tubes in an S shape, thereby extending the heat exchange time, improving the heat exchange effect, and further reducing the exhaust gas temperature.

[0010] As a further improvement of the present invention, the top of the inner cavity of the boiler shell is in an arc shape, which further improves the pressure bearing capacity of the boiler and improves the safety of use.

[0011] As a further improvement of the present invention, the burner adopts a layered cutting combustion low-nitrogen emission burner. During the entire process of boiler operation, according to the oxygen content in the flue gas, the layered cutting low-nitrogen burner automatically adjusts the air and fuel ratio, timely controls the ultra-low nitrogen emission of boiler flue gas NOx, and finally achieves low-nitrogen high-efficiency energy saving. And because the burner adopts layered cutting low-nitrogen combustion technology, there is no need to increase the size of the furnace, and there is no need to add an FGR flue gas recirculation pipeline, making the boiler structure more compact and beautiful, which not only saves manufacturing costs, but also greatly reduces the user's initial investment cost, while ensuring that the thermal efficiency of the boiler is not affected.

[0012] As a further improvement of the present invention, the water cavity is filled with water, and an overflow pipe seat is provided on the top of the boiler shell, so that the boiler structure of the present invention can be used as an indirect hot water boiler.

[0013] As a further improvement of the present invention, a steam space is provided on the upper side of the water cavity and a steam valve is provided on the top of the boiler shell, so that the boiler structure of the present invention can be used as a vacuum heat exchange steam boiler.

[0014] As a further improvement of the present invention, the furnace is corrugated in the horizontal direction, which not only increases the radiation heating area and its rigidity, but also avoids excessive internal stress, helps to reduce the thickness of the furnace and save material costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of an embodiment of the energy-saving and environmentally friendly horizontal three-pass boiler structure of the present invention.

[0016] Figure 2 for Figure 1 Top view of the .

[0017] Figure 3 for Figure 1 Side view of.

[0018] Figure 4 It is a schematic diagram of another embodiment of the energy-saving and environmentally friendly horizontal three-pass boiler structure of the present invention.

[0019] Figure 5 for Figure 4 Top view of the .

[0020] Among them, 1 boiler shell, 2 burner, 3 condenser, 3A condenser heat exchange tube, 4 heat exchanger, 4A heat exchange tube, 5 furnace, 6 backfire chamber, 6A front end plate, 6B rear end plate, 6C upper tube plate, 6D lower tube plate, 6E left arc plate, 6F right arc plate, 7 water cavity, 8 flue gas partition wall, 9 light tube heat exchange tube, 10 finned heat exchange tube, 11 steam space, 12 steam valve, 13 overflow pipe seat, 14 chimney, 15 temperature sensor. DETAILED DESCRIPTION

[0021] Below, before describing the energy-saving and environmentally friendly horizontal three-pass boiler structure of the present invention in detail, it should be made clear that the terms "up", "down", "front", "back", "left", "right", "top", "bottom", "inside", "outside", "side", "end", "vertical", "horizontal" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the structure referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0022] like Figure 1-3 The energy-saving and environmentally friendly horizontal three-pass boiler structure shown includes a horizontally arranged boiler shell 1, a burner 2 is provided on the lower side of the front end of the boiler shell 1, a condenser 3 is provided on the lower side of the rear end of the boiler shell 1, and a heat exchanger 4 is provided on the upper side of the rear end of the boiler shell 1. The heat exchange tube 4A of the heat exchanger 4 extends into the upper side of the inner cavity of the boiler shell 1.

[0023] A furnace 5 and a reburning chamber 6 are provided at the lower side of the inner cavity of the boiler shell 1. The front end of the furnace 5 is connected to the burner 2 through the burner pipe. The rear end of the furnace 5 is connected to the reburning chamber 6. A water cavity 7 is formed between the outer sides of the furnace 5 and the reburning chamber 6 and the inner wall of the boiler shell 1. The furnace 5 is corrugated in the horizontal direction, which not only increases the radiation heating area and its rigidity, but also avoids excessive internal stress, helps to reduce the thickness of the furnace 5 and save material costs. A smoke outlet is provided at the rear end of the reburning chamber 6, which is connected to the smoke inlet of the condenser 3, and the smoke outlet of the condenser 3 is connected to the chimney 14. A condenser water inlet is provided on the condenser 3 at one end close to its smoke outlet, and a condenser water outlet is provided on the other end close to its smoke inlet. The water outlet of the condenser 3 is connected to the water inlet of the heat exchanger 4, and the condenser 3, the heat exchanger 4 and the water supply system are circulated and operated as a whole.

[0024] The flue gas and medium flow of this embodiment is as follows:

[0025] Flue gas flow (such as Figure 1-2 The solid arrow in the middle indicates the following steps: fuel → burner → furnace → front section of the regenerative chamber (light tube heat exchange tube) → rear section of the regenerative chamber (finned heat exchange tube) → condenser → chimney.

[0026] Soda system (such as Figure 1 The process is as follows: (indicated by the hollow arrow): softened water supply → water tank → circulating pump → condenser → water inlet of heat exchanger → outlet pipe seat of heat exchanger → water distribution cylinder → heat user → condenser.

[0027] Among them, a flue gas partition wall 8 is provided in the middle of the reburning chamber 6, and a flue gas passage is left between the flue gas partition wall 8 and the left inner wall of the reburning chamber 6. A light tube heat exchange tube 9 is provided on the front side of the flue gas partition wall 8, and a fin heat exchange tube 10 is provided on the rear side of the flue gas partition wall 8. The light tube heat exchange tube 9 and the fin heat exchange tube 10 are arranged vertically and are connected to the water cavity 7 inside. The light tube heat exchange tube 9 is used on the front side of the flue gas partition wall 8, which has good temperature resistance and avoids damage to the flue gas partition wall caused by direct contact with high-temperature flue gas. The fin heat exchange tube 10 is used on the rear side, which can double the convection heat exchange area of ​​the boiler and improve the heat exchange effect. In addition, by setting the flue gas partition wall 8, the length of the flue in the reburning chamber is extended, further improving the thermal efficiency of the boiler. This structure rationally arranges a large number of heat exchange tube bundles in a relatively small space, thereby increasing the radiation and convection heating surfaces, extending the flue gas flow path, greatly improving the boiler heat transfer efficiency, and reducing the flue gas resistance (boiler back pressure), making the burner 2 consume less power and more energy-efficient.

[0028] Specifically, the structure of the reburning chamber is as follows:

[0029] The reburning chamber 6 is in the shape of an elongated cylinder, and includes a front end plate 6A, a rear end plate 6B, an upper tube plate 6C, a lower tube plate 6D, a left arc plate 6E, and a right arc plate 6F. The upper and lower ends of the smoke partition wall 8 are respectively welded and fixed to the upper tube plate 6C and the lower tube plate 6D, and the right side of the smoke partition wall 8 is welded and fixed to the right arc plate 6F. The two ends of the light tube heat exchange tube 9 and the fin heat exchange tube 10 are respectively connected to the upper tube plate 6C and the lower tube plate 6D. Among them, the curvature of the left arc plate 6E is greater than that of the right arc plate 6F, which is convenient for the flue gas to turn, and increases the pressure bearing performance of the reburning chamber 6, thereby improving the safety of the equipment. In this embodiment, the rear end plate 6B is the rear end wall of the boiler shell 1, which greatly simplifies the boiler structure and saves material costs.

[0030] like Figure 1 As shown, several groups of condenser heat exchange tubes 3A are provided in the condenser 3. Specifically, in this embodiment, three groups of condenser heat exchange tubes 3A are provided in the condenser 3, each group of condenser heat exchange tubes 3A includes three condenser heat exchange tubes 3A, and the three groups of condenser heat exchange tubes 3A are arranged in series, so that the cold fluid flows in the three groups of condenser heat exchange tubes 3A in an S shape, which prolongs the heat exchange time, improves the heat exchange effect, and further reduces the exhaust gas temperature.

[0031] In this embodiment, a steam space 11 is provided on the upper side of the water cavity 7, and a steam valve 12 is provided on the top of the boiler shell 1. The top of the inner cavity of the boiler shell 1 is in an arc shape, which further improves the pressure bearing capacity of the boiler and improves the safety of use, so that the boiler structure of this embodiment can be used as a vacuum heat exchange steam boiler.

[0032] Burner 2 adopts layered cutting combustion low nitrogen emission burner 2. During the entire process of boiler operation, according to the oxygen content in the flue gas, the layered cutting low nitrogen burner 2 automatically adjusts the air and fuel ratio, timely controls the ultra-low nitrogen emission of boiler flue gas NOx, and finally achieves low nitrogen and high efficiency energy saving. And because burner 2 adopts layered cutting low nitrogen combustion technology, there is no need to increase the size of the furnace, and there is no need to add an FGR flue gas recirculation pipeline, making the boiler structure more compact and beautiful, which not only saves manufacturing costs, but also greatly reduces the user's initial investment cost, while ensuring that the thermal efficiency of the boiler is not affected. The heat exchanger 4 adopts a U-tube heat exchanger 4, which further simplifies the boiler structure and facilitates the disassembly and maintenance of the heat exchanger 4, reducing the manufacturing and maintenance costs. A temperature sensor 15 is also provided on the top of the boiler shell 1 to facilitate real-time monitoring of the temperature inside the boiler shell 1.

[0033] Figure 4-5 Another embodiment of the energy-saving and environmentally friendly horizontal three-pass boiler structure of the present invention is shown. Figure 1-3 Compared with the embodiment shown, the main differences are:

[0034] 1. Internal combustion chamber structure. In this embodiment, the rear end plate 6B is a separate structure, so that there is a gap between the rear end plate 6B and the rear end wall of the boiler shell 1 and the rear end plate 6B is connected to the water cavity, thereby avoiding excessive temperature of the rear end wall of the boiler shell 1 and preventing heat loss.

[0035] 2. The water cavity 7 is filled with water, an overflow pipe seat 13 is provided on the top of the boiler shell 1, and there is no steam valve, so that the boiler structure of this embodiment can be used as an indirect hot water boiler.

[0036] In the energy-saving and environment-friendly horizontal three-pass boiler structure of the present invention, the burner 2 burns in the furnace 5 to generate high-temperature flue gas, which is radiated and laterally flushed through the front section of the regenerative chamber 6 arranged with light tube heat exchange tubes 9 for convection tube bundles of the light tube heat exchange tubes 9 in the second return, and then turned to the flue gas partition wall 8 in the regenerative chamber 6 to laterally flush the convection tube bundles of the finned heat exchange tubes 10 for sufficient heat exchange in the third return, and then further heat exchanged through the tail condenser 3 and discharged to the chimney, so that the exhaust temperature of the boiler can be finally reduced to less than 80°C, so that the designed thermal efficiency of the main body is as high as 96%.

[0037] The present invention is not limited to the above-mentioned embodiments. On the basis of the technical solution disclosed in the present invention, technicians in this field can make some substitutions and deformations to some technical features therein according to the disclosed technical content without creative labor, and these substitutions and deformations are all within the protection scope of the present invention.

Claims

1. An energy-saving and environmentally friendly horizontal three-pass boiler structure, comprising a horizontally arranged boiler shell, characterized in that: A burner is provided at the lower side of the front end of the boiler shell, a condenser is provided at the lower side of the rear end of the boiler shell, a heat exchanger is provided at the upper side of the rear end of the boiler shell, a heat exchange pipe of the heat exchanger extends into the upper side of the inner cavity of the boiler shell, a furnace gallbladder and a backfire chamber are provided at the lower side of the inner cavity of the boiler shell, the front end of the furnace gallbladder is connected to the burner, the rear end of the furnace gallbladder is communicated with the backfire chamber, a water cavity is formed between the outer sides of the furnace gallbladder and the backfire chamber and the inner wall of the boiler shell, a smoke outlet is provided at the rear end of the backfire chamber, the smoke outlet is communicated with the smoke inlet of the condenser, the water outlet of the condenser is communicated with the water inlet of the heat exchanger, a smoke partition wall is provided in the middle of the backfire chamber, a smoke passage is left between the smoke partition wall and the left inner wall of the backfire chamber, a light tube heat exchange pipe is provided on the front side of the smoke partition wall, a fin heat exchange pipe is provided on the rear side of the smoke partition wall, the light tube heat exchange pipe and the fin heat exchange pipe are vertically arranged and internally communicated with the water cavity.

2. The energy-saving and environmentally friendly horizontal three-pass boiler structure according to claim 1 is characterized by: The reburning chamber is in the shape of an elongated cylinder and includes a front end plate, a rear end plate, an upper tube plate, a lower tube plate, a left arc-shaped plate, and a right arc-shaped plate. The upper and lower ends of the smoke partition wall are respectively welded and fixed to the upper tube plate and the lower tube plate, and the right side of the smoke partition wall is welded and fixed to the right arc-shaped plate. The two ends of the bare tube heat exchange tube and the fin heat exchange tube are respectively connected to the upper tube plate and the lower tube plate, and the curvature of the left arc-shaped plate is greater than that of the right arc-shaped plate.

3. The energy-saving and environmentally friendly horizontal three-pass boiler structure according to claim 2 is characterized by: There is a gap between the rear end plate and the rear end wall of the pot shell.

4. The energy-saving and environmentally friendly horizontal three-pass boiler structure according to claim 1 is characterized by: The heat exchanger is a U-tube heat exchanger.

5. The energy-saving and environmentally friendly horizontal three-pass boiler structure according to claim 1 is characterized by: A plurality of groups of condenser heat exchange tubes are arranged in series in the condenser.

6. The energy-saving and environmentally friendly horizontal three-pass boiler structure according to any one of claims 1 to 5, characterized in that: The top of the inner cavity of the pot shell is in an arc shape.

7. The energy-saving and environmentally friendly horizontal three-pass boiler structure according to any one of claims 1 to 5, characterized in that: The burner adopts a layered cutting combustion low nitrogen emission burner.

8. The energy-saving and environmentally friendly horizontal three-pass boiler structure according to any one of claims 1 to 5, characterized in that: The water cavity is filled with water, and an overflow pipe seat is arranged on the top of the pot shell.

9. The energy-saving and environmentally friendly horizontal three-pass boiler structure according to any one of claims 1 to 5, characterized in that: A steam space is arranged on the upper side of the water cavity, and a steam valve is arranged on the top of the pot shell.

10. The energy-saving and environmentally friendly horizontal three-pass boiler structure according to any one of claims 1 to 5, characterized in that: The furnace is corrugated in the horizontal direction.

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