A spiral plate heat exchanger boiler

Abstract

The application provides a spiral plate heat exchange boiler, which comprises a boiler body and a spiral plate heat exchanger arranged above the boiler body, a concentric spiral channel formed by winding a metal plate is arranged in the spiral plate heat exchanger, the spiral channel comprises a flue gas channel for conveying flue gas and a water channel adjacent to the flue gas channel and used for conveying desalted water, the flue gas channel and the water channel are not communicated with each other, the spiral plate heat exchanger comprises a flange disc arranged at the bottom end periphery, an end cover detachably connected with the flange disc and a sealing gasket arranged between the end cover and the metal plate. The spiral plate heat exchange boiler can reduce cost and prevent the heat exchanger from being covered with dust by combining the spiral plate heat exchanger with the boiler.

Description

Technical Field

[0001] This application belongs to the field of boiler heat exchange, specifically relating to a spiral plate heat exchange boiler, which is suitable for industrial waste heat recovery, civil heating and other fields. Background Technology

[0002] A boiler is a device that uses the heat energy released by fuel combustion to heat feedwater and produce steam or hot water. It is widely used in industry, energy, heating and other fields. The flue gas emitted after boiler combustion (usually above 150°C or even higher) carries a large amount of sensible heat and some latent heat. Direct emission will cause energy waste and thermal pollution. Traditional boilers often use flue-type bare tube heat exchangers combined with the boiler to utilize waste heat.

[0003] A flue-type bare tube heat exchanger consists of heat exchange tubes, tube sheets, and a tube box. The heat exchange tubes form the flue gas flow channels, while the spaces between multiple heat exchange tubes in the tube bundle are water channels. Waste heat from the boiler flue gas is recovered and utilized through the heat exchanger, thus saving a significant amount of energy. However, when using a flue-type bare tube heat exchanger, dust accumulates inside the tubes or in the tube box, making cleaning difficult and leading to dust buildup. Furthermore, the fixed tube sheet structure results in thermal expansion and contraction stress, and the acidic corrosive medium formed after the flue gas cools down causes stress corrosion cracking to quickly form between the heat exchange tubes and the tube sheet. Therefore, flue-type bare tube heat exchangers suffer from problems such as high cost, susceptibility to corrosion and cracking, easy dust accumulation, and large size.

[0004] CN2572280Y discloses a spiral plate boiler, including a furnace body, a furnace chamber formed by the space enclosed by the furnace body, a flue located at the top of the furnace body and communicating with the furnace chamber, a heated medium inlet, and a heated medium outlet. A heated medium channel is formed within the furnace chamber by metal plates, and the heated medium channel has a spiral cross-section. The two sides of the longitudinal surface of the heated medium channel are connected to and sealed with the two sides of the furnace chamber. A fire inlet communicating with the furnace chamber is located in the central area of ​​one side of the furnace chamber. This utility model is essentially a boiler body, with the heated medium channel forming a spiral within the furnace chamber, and does not involve flue gas utilization. Utility Model Content

[0005] In view of the problems existing in the prior art, this utility model provides a spiral plate heat exchanger boiler, which reduces costs and prevents ash accumulation in the heat exchanger by combining the spiral plate heat exchanger with the boiler.

[0006] A spiral plate heat exchanger boiler includes a boiler body and a spiral plate heat exchanger disposed above the boiler body. The spiral plate heat exchanger has concentric spiral channels formed by winding metal plates inside. The spiral channels include flue gas channels arranged at intervals for conveying flue gas and water channels adjacent to the flue gas channels for conveying water (preferably demineralized water). The flue gas channels and water channels are not interconnected. The spiral plate heat exchanger includes a flange arranged around the bottom periphery, an end cover detachably connected to the flange, and a sealing gasket disposed between the end cover and the metal plate (the lower end of the metal plate and the flange).

[0007] Furthermore, a flue gas outlet is provided at the top of the boiler body for outputting the high-temperature flue gas generated by combustion.

[0008] Furthermore, the spiral plate heat exchanger is provided with a flue gas inlet, a flue gas outlet, a water inlet, and a water outlet. The flue gas inlet and water outlet extend axially from the center of the spiral plate heat exchanger, with opposite extension directions. The water outlet extends from the top, while the flue gas outlet and water inlet extend tangentially from the outermost side of the spiral plate heat exchanger, with opposite extension directions. The flue gas inlet and outlet are connected via a flue gas channel, and the water inlet and outlet are connected via a water channel. The flue gas outlet pipe of the boiler body is connected to the flue gas inlet of the spiral plate heat exchanger, and the flue gas outlet of the spiral plate heat exchanger is connected to the chimney. For example, the flue gas inlet, outlet, water inlet, and outlet are all short pipes. The high-temperature flue gas in the boiler body is input into the flue gas channel of the spiral plate heat exchanger through the flue gas outlet pipe. The demineralized water is input into the water channel through the side water inlet. After the demineralized water undergoes indirect heat exchange with the flue gas to recover the waste heat of the flue gas, it is discharged from the top water outlet.

[0009] Furthermore, the metal plate includes a first metal plate and a second metal plate. A baffle is provided at the center of the spiral plate heat exchanger. The two opposite side edges of the baffle are connected to the first metal plate and the second metal plate, respectively. The first metal plate and the second metal plate are wound in the same direction to form a spiral channel. A first semi-circular chamber connected to the water outlet is formed between the baffle and the first metal plate. The first semi-circular chamber is connected to the water channel. A second semi-circular chamber connected to the flue gas inlet is formed between the baffle and the second metal plate. The second semi-circular chamber is connected to the flue gas channel. The metal plate can be made of high-temperature resistant stainless steel to prevent condensation of flue gas at low temperatures and corrosion of the medium. Compared with a flue-type bare tube heat exchanger made of stainless steel, this method saves steel, simplifies manufacturing, and reduces labor costs.

[0010] Furthermore, the metal plates at the top and bottom of the water channel are connected by a spiral sealing round steel, for example by welding, to form a closed flow channel. The top and bottom of the first semi-circular chamber are both connected to a semi-circular sealing steel body, wherein the sealing steel body at the top has a first through hole connected to the water outlet.

[0011] Furthermore, the metal plates at the top of the flue gas passage are connected by a spiral sealing strip, for example, by welding. The top of the second semi-circular chamber is provided with a semi-circular sealing plate, and a spiral opening is formed between the metal plates at the bottom of the flue gas passage. A semi-circular opening is also formed at the bottom of the second semi-circular chamber.

[0012] Furthermore, the sealing gasket is used to seal the spiral opening and the semi-circular opening, and the sealing gasket has a second through hole.

[0013] Furthermore, a third through hole is provided on the end cover, which is coaxially connected to the flue gas inlet. Preferably, the end cover and the flue gas inlet are integrally formed. When the end cover is connected to the flange, the second through hole and the third through hole are coaxial, and the second semi-circular cavity completely covers the second through hole to prevent the flue gas from running around.

[0014] Furthermore, the flange has a first connection hole, the end cover has a second connection hole, and the gasket has a third connection hole. The first, second, and third connection holes are coaxial. After the bolt passes through the first, second, and third connection holes, it is tightened with the matching nut to achieve a seal for the spiral opening and the semi-circular opening.

[0015] Furthermore, multiple layers of spacers are provided between adjacent metal plates. These spacers are arranged sequentially at intervals along the height of the spiral plate heat exchanger. Multiple spacers within each layer are distributed radially along the spiral plate heat exchanger. The spacers are used to improve the pressure-bearing capacity of the metal plates and increase the rigidity and stability of the spiral plate heat exchanger. At the same time, when dust in the flue gas passes through the flue gas channel, the swirling structure of the flue gas channel and the scouring effect of the spacers cause the dust to deposit on the sealing gasket at the bottom of the spiral plate heat exchanger. After a period of use, the end cover and sealing gasket are removed to release the accumulated dust and to purge and clean the flue gas channel.

[0016] The beneficial effects of this utility model are: This utility model discloses a spiral plate heat exchanger boiler. By setting concentric spiral channels formed by wound metal plates inside the spiral plate heat exchanger, under the same heat exchange area, the spiral plate heat exchanger has a smaller volume and lower cost compared to a flue-type bare tube heat exchanger. The flue gas channel and water channel are formed by wound metal plates, and thermal expansion and contraction are integrated, allowing thermal stress to be absorbed between the channels. Compared with the flue-type bare tube heat exchanger, there is no opening stress or thermal stress (pull-out force) caused by thermal expansion and contraction, which will not cause stress corrosion and is safe and reliable to use. Demineralized water and flue gas undergo indirect heat exchange in the water channel and flue gas channel respectively to recover the waste heat of the flue gas. The end cover and flange are detachably connected, and a spacer column is set between adjacent metal plates. The spiral structure of the flue gas channel and the scouring of the spacer column cause dust to accumulate on the sealing gasket at the bottom of the spiral plate heat exchanger. After a period of use, the end cover and sealing gasket are removed to release the accumulated dust and the flue gas channel is purged and cleaned. This application is an organic combination of spiral plate heat exchanger and boiler, which reduces costs, reduces volume, and prevents ash accumulation. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of an overall spiral plate heat exchanger boiler according to the present invention.

[0018] Figure 2 This is a schematic diagram of a spiral plate heat exchanger from a first-person perspective.

[0019] Figure 3 This is a schematic diagram of a spiral plate heat exchanger from a second perspective.

[0020] Figure 4 This is a top view of a spiral plate heat exchanger.

[0021] Figure 5 for Figure 4 Cross-sectional stereoscopic view along the AA direction.

[0022] Figure 6 for Figure 5 Enlarged view of point C.

[0023] Figure 7 for Figure 5 Enlarged view of point D in the middle.

[0024] Figure 8 This is a schematic diagram of a spiral opening and a semi-circular opening.

[0025] Figure 9 This is the front view of a spiral plate heat exchanger.

[0026] Figure 10 for Figure 9 Cross-sectional view along the BB direction.

[0027] Explanation of reference numerals in the attached figures: 1-Boiler body, 101-Flue gas outlet, 2-Spiral plate heat exchanger, 201-Flange, 202-End cover, 203-Sealing gasket, 204-Flue gas inlet, 205-Flue gas outlet, 206-Water inlet, 207-Water outlet, 3-Metal plate, 301-First metal plate, 302-Second metal plate, 4-Flue gas passage, 5-Water passage, 6-Baffle, 701-First semi-circular chamber, 702-Second semi-circular chamber, 8-Sealing round steel, 9-Semi-circular sealing steel body, 10-Sealing strip, 11-Semi-circular sealing plate, 12-Spiral opening, 13-Semi-circular opening, 14-First connecting hole, 15-Second connecting hole, 16-Spacer column. Detailed Implementation

[0028] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0030] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0031] like Figure 1-10As shown, a spiral plate heat exchanger boiler includes a boiler body 1 and a spiral plate heat exchanger 2 disposed above the boiler body 1. The spiral plate heat exchanger 2 has a concentric spiral channel formed by a metal plate 3. The spiral channel includes a flue gas channel 4 arranged at intervals for conveying flue gas and a water channel 5 adjacent to the flue gas channel 4 for conveying water (demineralized water). The flue gas channel 4 and the water channel 5 are not connected to each other. The spiral plate heat exchanger 2 includes a flange 201 arranged around the bottom periphery, an end cover 202 detachably connected to the flange 201, and a sealing gasket 203 disposed between the end cover 202 and the metal plate (the lower end of the metal plate 3 and the flange 201).

[0032] like Figure 1 As shown, the top of the boiler body 1 is provided with a flue gas outlet 101 for outputting high-temperature flue gas generated by combustion.

[0033] like Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 8 , Figure 9 As shown, the spiral plate heat exchanger 2 is provided with a flue gas inlet 204, a flue gas outlet 205, a water inlet 206, and a water outlet 207. The flue gas inlet 204 and the water outlet 207 extend axially from the center of the spiral plate heat exchanger 2, with opposite extension directions. The water outlet 207 extends from the top. The flue gas outlet 205 and the water inlet 206 extend tangentially from the outermost side of the spiral plate heat exchanger 2, with opposite extension directions. The flue gas inlet 204 and the flue gas outlet 205 are connected via a flue gas passage 4, and the water inlet 206 is connected to the water outlet. The outlets 207 and 207 are connected by a water channel 5. The flue gas outlet 101 of the boiler body 1 is connected to the flue gas inlet 204 of the spiral plate heat exchanger 2. The flue gas outlet 205 of the spiral plate heat exchanger 2 is connected to the chimney. The flue gas inlet 204, the flue gas outlet 205, the water inlet 206, and the water outlet 207 are all, for example, short pipes. The high-temperature flue gas in the boiler body 1 is input into the flue gas channel 4 of the spiral plate heat exchanger 2 through the flue gas outlet 101. The demineralized water is input into the water channel 5 through the side water inlet 206. After the demineralized water and the flue gas undergo indirect heat exchange to recover the waste heat of the flue gas, it is discharged from the top water outlet 207.

[0034] like Figure 4 , Figure 5 , Figure 8 , Figure 10As shown, the metal plate 3 includes a first metal plate 301 and a second metal plate 302. A baffle 6 is provided at the center of the spiral plate heat exchanger 2. The two opposite side edges of the baffle 6 are connected to the first metal plate 301 and the second metal plate 302 respectively. The first metal plate 301 and the second metal plate 302 are wound in the same direction to form a spiral channel. A first semi-circular chamber 701 is formed between the baffle 6 and the first metal plate 301 and is connected to the water outlet 207. The first semi-circular chamber 701 is connected to the water channel 5. A second semi-circular chamber 702 is formed between the baffle 6 and the second metal plate 302 and is connected to the flue gas inlet 204. The second semi-circular chamber 702 is connected to the flue gas channel 4. The metal plate 3 can be made of high-temperature resistant stainless steel to prevent the flue gas from condensing and corroding the medium at low temperatures. Compared with the flue-type bare tube heat exchanger made of stainless steel, it saves steel, is simple to manufacture, and reduces labor costs.

[0035] like Figure 2 , Figure 5 , Figure 7 , Figure 8 As shown, the metal plates at the top and bottom of the water channel 5 are connected by a spiral sealing round steel 8, for example by welding, to form a closed flow channel. The top and bottom of the first semi-circular chamber 701 are connected to a semi-circular sealing steel body 9, wherein the sealing steel body at the top has a first through hole connected to the water outlet 207.

[0036] like Figure 5 , Figure 7 , Figure 8 As shown, the metal plates at the top of the flue gas passage 4 are connected by a spiral sealing strip 10, for example, by welding. The top of the second semi-circular chamber 702 is provided with a semi-circular sealing plate 11. A spiral opening 12 is formed between the metal plates at the bottom of the flue gas passage 4, and a semi-circular opening 13 is formed at the bottom of the second semi-circular chamber 702.

[0037] like Figure 5 , Figure 6 , Figure 8 As shown, the sealing gasket 203 is used to seal the spiral opening 12 and the semi-circular opening 13, and the sealing gasket 203 has a second through hole.

[0038] like Figure 3 , Figure 5 , Figure 10 As shown, the end cover 202 has a third through hole, which is coaxially connected to the flue gas inlet 204. Preferably, the end cover 202 and the flue gas inlet 204 are integrally formed. When the end cover 202 is connected to the flange 201, the second through hole and the third through hole are coaxial, and the second semi-circular cavity 702 completely covers the second through hole to prevent the flue gas from running around and only enters the flue gas passage.

[0039] like Figure 2 , Figure 3 , Figure 8 , Figure 10 As shown, the flange 201 has a first connecting hole 14, the end cover 202 has a second connecting hole 15, and the sealing gasket 203 has a third connecting hole. The first connecting hole 14, the second connecting hole 15, and the third connecting hole are coaxial. After the bolt passes through the first connecting hole 14, the second connecting hole 15, and the third connecting hole, it is tightened with the matching nut to achieve the sealing of the spiral opening 12 and the semi-circular opening 13.

[0040] like Figure 5 , Figure 8 , Figure 10 As shown, multiple layers of spacer columns 16 are provided between adjacent metal plates. The multiple layers of spacer columns 16 are arranged sequentially at intervals along the height direction of the spiral plate heat exchanger 2. Multiple spacer columns 16 in each layer are distributed radially along the spiral plate heat exchanger 2. The spacer columns 16 are used to improve the pressure bearing capacity of the metal plates and increase the rigidity and stability of the spiral plate heat exchanger 2. At the same time, when dust in the flue gas passes through the flue gas channel 4, the swirling structure of the flue gas channel 4 and the scouring of the spacer columns 16 cause the dust to be deposited on the sealing gasket 203 at the bottom of the spiral plate heat exchanger 2. After a period of use, the end cover 202 and the sealing gasket 203 are removed to release the accumulated dust and to blow and clean the flue gas channel 4.

[0041] This utility model discloses a spiral plate heat exchanger boiler that improves boiler efficiency and achieves energy-saving and environmental protection effects by recovering waste heat from flue gas. Taking a 10t / h gas-fired steam boiler as an example, the flue gas volume is 8800 Nm³. 3 The flue gas temperature entering spiral plate heat exchanger 2 is 150℃, and the flue gas temperature exiting spiral plate heat exchanger 2 is 80℃. The average specific heat capacity of the flue gas is 1.1 kJ / (Nm³). 3 .K), can recover 8800*1.1*(150-80)=677600KJ per hour, equivalent to 23.12kg of standard coal.

[0042] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A spiral plate heat exchanger boiler, characterized in that, It includes a boiler body (1) and a spiral plate heat exchanger (2) disposed above the boiler body (1). The spiral plate heat exchanger (2) is provided with a concentric spiral channel formed by a metal plate (3) inside. The spiral channel includes a flue gas channel (4) arranged at intervals for conveying flue gas and a water channel (5) adjacent to the flue gas channel (4) for conveying water. The flue gas channel (4) and the water channel (5) are not connected to each other. The spiral plate heat exchanger (2) includes a flange (201) arranged around the bottom edge, an end cover (202) detachably connected to the flange (201), and a sealing gasket (203) disposed between the end cover (202) and the metal plate.

2. The spiral plate heat exchanger boiler according to claim 1, characterized in that, The top of the boiler body (1) is provided with a flue gas outlet (101).

3. The spiral plate heat exchanger boiler according to claim 1 or 2, characterized in that, The spiral plate heat exchanger (2) is provided with a flue gas inlet (204), a flue gas outlet (205), a water inlet (206), and a water outlet (207). The flue gas inlet (204) and the water outlet (207) extend axially from the center of the spiral plate heat exchanger (2), respectively. The extension directions of the flue gas inlet (204) and the water outlet (207) are opposite. The water outlet (207) extends from the top, and the flue gas outlet (205) and the water inlet (206) extend from the outermost part of the spiral plate heat exchanger (2). The flue gas outlet (205) and the water inlet (206) extend tangentially along the side. The flue gas inlet (204) and the flue gas outlet (205) are connected through the flue gas channel (4). The water inlet (206) and the water outlet (207) are connected through the water channel (5). The flue gas outlet (101) of the boiler body (1) is connected to the flue gas inlet (204) of the spiral plate heat exchanger (2). The flue gas outlet (205) of the spiral plate heat exchanger (2) is connected to the chimney.

4. The spiral plate heat exchanger boiler according to claim 3, characterized in that, The metal plate (3) includes a first metal plate (301) and a second metal plate (302). The center of the spiral plate heat exchanger (2) is provided with a partition (6). The two opposite side edges of the partition (6) are connected to the first metal plate (301) and the second metal plate (302) respectively. The first metal plate (301) and the second metal plate (302) are wound in the same direction to form a spiral channel. A first semi-circular chamber (701) is formed between the partition (6) and the first metal plate (301) and is connected to the water outlet (207). The first semi-circular chamber (701) is connected to the water channel (5). A second semi-circular chamber (702) is formed between the partition (6) and the second metal plate (302) and is connected to the flue gas inlet (204). The second semi-circular chamber (702) is connected to the flue gas channel (4).

5. The spiral plate heat exchanger boiler according to claim 4, characterized in that, The metal plates at the top and bottom of the water channel (5) are connected by a spiral sealing round steel (8). The top and bottom of the first semi-circular chamber (701) are connected to a semi-circular sealing steel body (9), wherein the sealing steel body at the top has a first through hole connected to the water outlet (207).

6. The spiral plate heat exchanger boiler according to claim 4, characterized in that, The metal plates at the top of the flue gas passage (4) are connected by a spiral sealing strip (10). The top of the second semi-circular chamber (702) is provided with a semi-circular sealing plate (11). A spiral opening (12) is formed between the metal plates at the bottom of the flue gas passage (4). A semi-circular opening (13) is formed at the bottom of the second semi-circular chamber (702).

7. The spiral plate heat exchanger boiler according to claim 6, characterized in that, The sealing gasket (203) is used to seal the spiral opening (12) and the semi-circular opening (13), and the sealing gasket (203) has a second through hole.

8. The spiral plate heat exchanger boiler according to claim 7, characterized in that, The end cap (202) has a third through hole, which is coaxially connected to the flue gas inlet (204). The end cap (202) and the flue gas inlet (204) are integrally formed, and the second semi-circular chamber (702) completely covers the second through hole.

9. The spiral plate heat exchanger boiler according to claim 1, characterized in that, The flange (201) has a first connection hole (14), the end cover (202) has a second connection hole (15), and the gasket (203) has a third connection hole. The first connection hole (14), the second connection hole (15), and the third connection hole are coaxial.

10. The spiral plate heat exchanger boiler according to claim 1, characterized in that, Multiple spacer columns (16) are provided between adjacent metal plates. The multiple spacer columns (16) are arranged sequentially at intervals along the height direction of the spiral plate heat exchanger (2). Multiple spacer columns (16) in each layer are distributed radially along the spiral plate heat exchanger (2).

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