Energy-saving fire tube with good heat exchange effect for steam boiler

Abstract

The energy-saving fire tube comprises a shell, a preheating assembly and an inner container assembly are fixedly installed in the shell, a water inlet is fixedly formed in the position, corresponding to the preheating assembly, of the side face of the shell, one end of the water inlet penetrates through the shell and then is fixedly connected with the surface of the preheating assembly, and the other end of the water inlet is fixedly connected with the inner container assembly. The preheating assembly is located over the inner container assembly, a fire grate is fixedly installed at the position, located below the inner container assembly, of the bottom of the inner wall of the shell, the fire grate is fixedly connected with the bottom of the inner container assembly, and the preheating assembly comprises a preheating energy-saving fire tube. The main body energy-saving fire tube and the preheating energy-saving fire tube are both arranged to be of a spiral structure, the flowing path of high-temperature flue gas in the tubes is remarkably prolonged, the standing time of the high-temperature flue gas in the tubes is remarkably prolonged, the contact area of the heat exchange tubes and water is increased, and therefore the heat exchange efficiency of the high-temperature flue gas (gas) and the water is greatly improved, the exhaust gas temperature is effectively reduced, and the heat exchange efficiency is improved. The waste of heat energy is reduced, and a remarkable energy-saving effect is realized.

Description

Technical Field

[0001] This invention relates to the field of steam boiler technology, and in particular to an energy-saving fire tube for a steam boiler with good heat exchange effect. Background Technology

[0002] In existing steam boiler systems, fire tubes are widely used as core heat exchange components. They typically adopt a simple structure of sheet metal stretching or straight tube bending, playing a crucial role in transferring heat from flue gas to the medium outside the tube. This design forms the basis of traditional boiler heat exchange and has been used for a long time in various industrial and civil heating scenarios.

[0003] However, the traditional fire-tube structure has gradually revealed several key problems in long-term use, which seriously restrict the overall energy efficiency and economy of the boiler. First, because it is mostly a straight or simple bend, the flue gas flow path is short and straight, resulting in insufficient residence time of flue gas in the tube and a high flow velocity. A large amount of high-temperature flue gas is discharged without fully releasing heat, resulting in significant heat energy waste. Second, the smooth inner wall of the straight tube makes the flue gas flow tend to be laminar, with weak turbulence effect and large boundary layer thermal resistance, which further weakens the heat transfer efficiency of the tube wall. In order to achieve the necessary heat exchange load, the insufficient heat exchange per unit can usually only be compensated by increasing the number of fire tubes or extending the length of the pipe. This not only directly leads to the boiler being large in size and increasing material costs, but also makes the equipment structure bulky and occupies more space. At the same time, the complexity of manufacturing and maintenance also increases. In addition, the simple tube design makes it difficult to achieve reasonable organization and disturbance enhancement of flue gas flow, resulting in the overall thermal efficiency remaining at a low level for a long time, low energy utilization, and high operating costs.

[0004] Therefore, how to provide an energy-saving fire tube for a steam boiler with good heat exchange performance is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] One objective of this invention is to provide an energy-saving fire tube for a steam boiler with good heat exchange performance. This invention solves the problems in the background art.

[0006] An energy-saving fire tube for a steam boiler with good heat exchange effect according to an embodiment of the present invention includes a shell. The shell contains a preheating component and an inner liner component, respectively fixedly installed inside. A water inlet is fixedly installed on the side of the shell corresponding to the preheating component. One end of the water inlet passes through the shell and is fixedly connected to the surface of the preheating component. The preheating component is located directly above the inner liner component. A fire baffle is fixedly installed at the bottom of the inner wall of the shell below the inner liner component, and the fire baffle is fixedly connected to the bottom of the inner liner component. The preheating component includes a preheating energy-saving fire tube, and the inner liner component includes a main energy-saving fire tube. The preheating energy-saving fire tube and the main energy-saving fire tube are arranged in a spiral shape. A water pump, fixedly connected to the preheating component, is fixedly installed at the bottom of the inner wall of the shell near the fire baffle. An output pipe is fixedly installed on the output shaft of the water pump, and the other end of the output pipe is fixedly connected to the surface of the inner liner component. A steam vent is fixedly installed on the top of the shell, and a steam vent pipe is fixedly installed on the top of the inner liner component. The other end of the steam vent pipe passes through the shell and is fixedly connected to the bottom of the steam vent.

[0007] A filter is fixedly installed on the water inlet to filter the incoming pure water.

[0008] The preheating assembly also includes a preheating water tank, which is fixedly installed inside the shell by a bracket. The preheating energy-saving fire tube is fixedly installed inside the preheating water tank. The bottom end of the preheating energy-saving fire tube passes through the preheating water tank and extends to the outside of the preheating water tank, and the top end of the preheating energy-saving fire tube passes through the preheating water tank and extends to the outside of the preheating water tank.

[0009] The inner tank assembly also includes an inner tank body and a connecting cover. The inner tank body is fixedly installed inside the shell by a fixing bracket and is located directly below the preheating water tank. The connecting cover is fixedly installed at the bottom of the inner tank body. The main energy-saving fire tube is fixedly installed inside the inner tank body, and the bottom end of the main energy-saving fire tube passes through the inner tank body and communicates with the connecting cover. The connecting cover is fixedly connected to the fire drain. The input end of the water pump is fixedly connected to and communicates with the preheating water tank, and the output pipe is fixedly connected to and communicates with the surface of the inner tank body.

[0010] A fixed cover is fixedly installed on the top of the inner tank body. The top end of the main energy-saving fire tube passes through the inner tank body and communicates with the fixed cover. The preheating water tank is built inside the fixed cover. A fan is fixedly installed on the top of the fixed cover. Both ends of the preheating energy-saving fire tube are connected to the inside of the fixed cover.

[0011] The preheating energy-saving fire tube and the main energy-saving fire tube are internally fixedly installed with flow guide ribs.

[0012] The preheating energy-saving fire tube and the main energy-saving fire tube extend in a cylindrical spiral shape along the central axis.

[0013] The preheating energy-saving fire tube and the main energy-saving fire tube are made of high-temperature corrosion resistant seamless steel pipes.

[0014] The beneficial effects of this invention are: This invention significantly extends the flow path and residence time of high-temperature flue gas within the tubes by setting both the main energy-saving fire tube and the preheating energy-saving fire tube to a spiral structure, and increases the contact area between the heat exchange tube and water. This greatly improves the heat exchange efficiency between high-temperature flue gas (gas) and water, effectively reduces the exhaust temperature, reduces heat waste, and achieves significant energy-saving effects.

[0015] By adding guide fins inside the spiral fire tube, the contact area between the tube wall and the flue gas is further increased. At the same time, the turbulence disturbance inside the tube is enhanced, which effectively destroys the thermal resistance boundary layer of the flue gas flow, improves the overall convective heat transfer coefficient, and makes the heat exchange more complete and rapid, thereby further improving the energy utilization rate.

[0016] This invention innovatively adopts a flue gas waste heat recovery design, which introduces the flue gas, which still has residual heat after heat exchange in the main energy-saving fire tube, into the preheating energy-saving fire tube located above to preheat the clean water that is about to enter the inner tank. This energy cascade utilization method makes full use of the waste heat of the flue gas, reduces the main heat energy consumption required to heat room temperature water to boiling, and further reduces gas consumption at the system level.

[0017] The entire system has a compact and reasonable structural design. The spiral fire tubes achieve an ultra-long heat exchange stroke within a limited space. The preheating water tank is integrated into a fixed cover. The fan drives the flue gas to flow in a directional manner. This design allows the equipment to maintain high thermal efficiency while being relatively small in size, reducing material and space occupation and lowering manufacturing and installation costs.

[0018] The fire tubes are made of high-quality stainless steel that is resistant to high temperatures and corrosion, and combined with optimized spiral structure parameters (such as spiral diameter, pitch and number of turns), the fire tubes have excellent durability and corrosion resistance in harsh high-temperature flue gas environments, which extends the service life of core heat exchange components and reduces maintenance frequency and cost. Attached Figure Description

[0019] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a front view schematic diagram of an energy-saving fire tube for a steam boiler with good heat exchange effect proposed in this invention.

[0020] Figure 2 This is a schematic diagram of the preheating component and inner tank component in an energy-saving fire tube for a steam boiler with good heat exchange effect proposed in this invention.

[0021] Figure 3This is a schematic diagram of the internal structure of the preheating component and inner tank component in an energy-saving fire tube for a steam boiler with good heat exchange effect, as proposed in this invention.

[0022] Figure 4 This is a schematic diagram of the internal side structure of the preheating component and inner liner component in an energy-saving fire tube for a steam boiler with good heat exchange effect, as proposed in this invention.

[0023] Figure 5 This is a three-dimensional cross-sectional structural diagram of the preheating energy-saving fire tube and the main energy-saving fire tube in an energy-saving fire tube for a steam boiler with good heat exchange effect proposed in this invention.

[0024] The attached diagram shows: 1. Shell; 2. Preheating assembly; 3. Inner tank assembly; 4. Water inlet; 5. Burner; 6. Preheating energy-saving burner tube; 7. Main energy-saving burner tube; 8. Water pump; 9. Output pipe; 10. Steam vent; 11. Steam vent pipe; 12. Filter; 13. Preheating water tank; 14. Inner tank body; 15. Connecting cover; 16. Fixing cover; 17. Fan; 18. Guide ribs. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0026] refer to Figure 1-5 In this embodiment, a preheating component 2 and an inner tank component 3 are fixedly installed inside the shell 1. A water inlet 4 is fixedly installed on the side of the shell 1 corresponding to the preheating component 2. A filter 12 for filtering the incoming pure water is fixedly installed on the water inlet 4. One end of the water inlet 4 passes through the shell 1 and is fixedly connected to the surface of the preheating component 2. The preheating component 2 is located directly above the inner tank component 3. A burner 5 is fixedly installed at the bottom of the inner wall of the shell 1 below the inner tank component 3. The burner 5 is fixedly connected to the bottom of the inner tank component 3. The preheating component 2 includes a preheating energy-saving burner 6, and the inner tank component 3 includes a main energy-saving burner 7. The preheating energy-saving burner 6 and the main energy-saving burner 7 are arranged in a spiral shape.

[0027] In specific implementation, in order to ensure that the gas carrying heat stays in the main energy-saving fire tube 7 and the preheating energy-saving fire tube 6 for a sufficient time, the main energy-saving fire tube 7 and the preheating energy-saving fire tube 6 are arranged in a spiral shape to increase the contact time and contact area between the gas and water. In order to further enhance heat conduction, flow guide ribs 18 are fixedly installed inside the preheating energy-saving fire tube 6 and the main energy-saving fire tube 7. The flow guide ribs 18 increase the contact area between the preheating energy-saving fire tube 6 and the main energy-saving fire tube 7 and the gas, further enhancing the heat conduction performance. At the same time, it also strengthens the turbulent disturbance inside the preheating energy-saving fire tube 6 and the main energy-saving fire tube 7, which can destroy the gas flow boundary layer, change the flow pattern, reduce thermal resistance, increase the convective heat transfer coefficient, and further save gas consumption. Initially, water enters from the inlet 4 and is filtered by the filter 12.

[0028] The inner tank assembly 3 also includes an inner tank body 14 and a connecting cover 15. The inner tank body 14 is fixedly installed inside the shell 1 by a fixing bracket and is located directly below the preheating water tank 13. The connecting cover 15 is fixedly installed at the bottom of the inner tank body 14. The main energy-saving fire tube 7 is fixedly installed inside the inner tank body 14, and the bottom end of the main energy-saving fire tube 7 passes through the inner tank body 14 and communicates with the connecting cover 15. The connecting cover 15 is fixedly connected to the burner 5. The connecting cover 15 fixes and seals the burner 5 and the inner tank body 14 to prevent heat loss. In this way, all the generated hot air is concentrated in the connecting cover 15 and then enters the main energy-saving fire tube 7 from the connecting cover 15. The input end of the water pump 8 is fixedly connected and communicates with the preheating water tank 13, and the output pipe 9 is fixedly connected and communicates with the surface of the inner tank body 14.

[0029] In practice, the burner 5 is activated, and the hot air generated by the burner 5 enters the interior of the main energy-saving burner tube 7 through the connecting cover 15. The gas with sufficient heat is heated by the pure water inside the inner liner 14 of the main energy-saving burner tube 7 to produce water vapor.

[0030] The preheating assembly 2 also includes a preheating water tank 13, which is fixedly installed inside the housing 1 by a bracket. The preheating energy-saving fire tube 6 is fixedly installed inside the preheating water tank 13. The bottom end of the preheating energy-saving fire tube 6 passes through the preheating water tank 13 and extends to the outside of the preheating water tank 13. The top end of the preheating energy-saving fire tube 6 passes through the preheating water tank 13 and extends to the outside of the preheating water tank 13.

[0031] In practice, the exhaust gas discharged through the main energy-saving fire tube 7 still carries residual heat. Direct discharge here would be wasteful, so it is introduced into the preheating energy-saving fire tube 6. The filtered water enters the preheating water tank 13 and is preheated by the pure water in the preheating water tank 13 in the waste heat energy-saving fire tube, so that the water inside becomes warm water.

[0032] A water pump 8, which is fixedly connected to the preheating component 2, is fixedly installed at the bottom of the inner wall of the housing 1 near the fire burner 5. An output pipe 9 is fixedly installed on the output shaft of the water pump 8. The other end of the output pipe 9 is fixedly connected to the surface of the inner liner component 3. A steam vent 10 is fixedly installed on the top of the housing 1. A steam vent pipe 11 is fixedly installed on the top of the inner liner component 3. The other end of the steam vent pipe 11 passes through the housing 1 and is fixedly connected to the bottom end of the steam vent 10.

[0033] In practice, the water pump 8 transports the preheated warm water inside the preheated water tank 13 through itself and the output pipe 9 to the inner tank body 14 for storage and heating. After the pure water inside the inner tank body 14 is heated, it generates water vapor, which reaches the steam outlet 10 through the steam exhaust pipe 11. The steam outlet 10 is connected to the external steam pipe, and then the steam from the steam outlet 10 is transported to terminal equipment such as rice steamer and steam cabinet through the external steam pipe for steaming food.

[0034] Example 1 refer to Figure 1-5 In this embodiment, a fixed cover 16 is fixedly installed on the top of the inner tank body 14. The top end of the main energy-saving fire tube 7 passes through the inner tank body 14 and communicates with the fixed cover 16. The preheating water tank 13 is built inside the fixed cover 16, thus wrapping the preheating water tank 13 to prevent exhaust gas from overflowing and to keep the preheating water tank 13 warm. A fan 17 is fixedly installed on the top of the fixed cover 16. Both ends of the preheating energy-saving fire tube 6 are connected to the inside of the fixed cover 16.

[0035] In practice, the fan 17 starts, and the fan 17 quickly draws the heat generated by the burner 5 into the main energy-saving fire tube 7. After heating the pure water inside the inner tank body 14, it enters the preheating energy-saving fire tube 6 through the fixed cover 16. Here, there is still some heat in the exhaust gas. After the exhaust gas enters the fixed cover 16, it reaches the preheating energy-saving fire tube 6. Then, it passes through the preheating energy-saving fire tube 6 to preheat the preheating water tank 13. After preheating, the exhaust gas is discharged by the fan 17. At this time, the exhaust gas has been cooled by the preheating water tank 13 before it reaches the fan 17. In this way, the temperature of the exhaust gas is not likely to damage the fan 17. The fan 17 is connected to the outside through a pipe, and the exhaust gas is discharged to the outside by the fan 17.

[0036] Example 2 refer to Figure 1-5In this embodiment, the preheating energy-saving fire tube 6 and the main energy-saving fire tube 7 are the same type of fire tube, which is referred to here as fire tube. The preheating energy-saving fire tube 6 and the main energy-saving fire tube 7 are high-temperature corrosion resistant seamless steel pipes. The fire tube is made of high-temperature corrosion resistant SUS304 seamless steel pipe, selected from 06Cr19Ni10 stainless steel. The preheating energy-saving fire tube 6 and the main energy-saving fire tube 7 extend in a cylindrical spiral shape along the central axis. The spiral diameter is 4-20 times the diameter of the preheating energy-saving fire tube 6 and the main energy-saving fire tube 7, the pitch is 1-5 times the diameter of the preheating energy-saving fire tube 6 and the main energy-saving fire tube 7, the number of spiral turns is 2-10 turns, the diameter of the fire tube is 16MM, the spiral diameter D=64MM (4 times the diameter), the pitch P=24MM (1.5 times the pipe diameter), the number of spiral turns N=7 turns, and the total length is approximately 1420MM (calculated according to the spiral length formula: L=πDN).

[0037] In practice, the use of the aforementioned materials in the steel pipes extends their service life.

[0038] The working principle of this invention is: During operation, clean water enters through inlet 4, is filtered by filter 12, and flows into preheating water tank 13. At the same time, the burner 5 starts to generate high-temperature flue gas. Under the suction of fan 17, the high-temperature flue gas enters the spiral main energy-saving fire tube 7 through connecting cover 15, and undergoes intense heat exchange with the water in the inner tank body 14, heating it to boiling and generating steam. After completing the main heat exchange, the flue gas with a lower temperature is discharged from the top of the main energy-saving fire tube 7, enters the fixed cover 16, and is introduced into the preheating energy-saving fire tube 6, which is also spiral-shaped. When the flue gas flows through the preheating energy-saving fire tube 6, its residual heat preheats the cold water in the preheating water tank 13. Subsequently, the low-temperature exhaust gas, after being fully utilized, is discharged to the outside by fan 17. On the other hand, the preheated warm water is drawn by water pump 8 and transported to the inner tank body 14 through output pipe 9 to replenish the evaporated water and continue to be heated. The water vapor generated in the inner tank is finally transported to the external steam-using equipment through the top exhaust pipe 11 and exhaust port 10.

[0039] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An energy-saving fire tube for a steam boiler with good heat exchange effect, comprising a shell (1), characterized in that, The preheating component (2) and the inner liner component (3) are fixedly installed inside the shell (1). A water inlet (4) is fixedly installed on the side of the shell (1) corresponding to the preheating component (2). One end of the water inlet (4) passes through the shell (1) and is fixedly connected to the surface of the preheating component (2). The preheating component (2) is located directly above the inner liner component (3). A fire bar (5) is fixedly installed at the bottom of the inner wall of the shell (1) below the inner liner component (3). The fire bar (5) is fixedly connected to the bottom of the inner liner component (3). The preheating component (2) includes a preheating energy-saving fire tube (6), and the inner liner component (3) includes a main energy-saving fire tube (7). The preheating energy-saving fire tube (6) and the main energy-saving fire tube (7) are arranged in a spiral shape. A water pump (8) that is fixedly connected to the preheating component (2) is fixedly installed at the bottom of the inner wall of the housing (1) near the fire vent (5). An output pipe (9) is fixedly installed on the output shaft of the water pump (8). The other end of the output pipe (9) is fixedly connected to the surface of the inner liner component (3). A steam vent (10) is fixedly installed on the top of the housing (1). A steam vent pipe (11) is fixedly installed on the top of the inner liner component (3). The other end of the steam vent pipe (11) passes through the housing (1) and is fixedly connected to the bottom end of the steam vent (10).

2. The energy-saving fire tube for a steam boiler with good heat exchange effect according to claim 1, characterized in that, A filter (12) for filtering the incoming pure water is fixedly installed on the water inlet (4).

3. The energy-saving fire tube for a steam boiler with good heat exchange effect according to claim 2, characterized in that, The preheating assembly (2) also includes a preheating water tank (13), which is fixedly installed inside the housing (1) by a bracket. The preheating energy-saving fire tube (6) is fixedly installed inside the preheating water tank (13). The bottom end of the preheating energy-saving fire tube (6) passes through the preheating water tank (13) and extends to the outside of the preheating water tank (13). The top end of the preheating energy-saving fire tube (6) passes through the preheating water tank (13) and extends to the outside of the preheating water tank (13).

4. The energy-saving fire tube for a steam boiler with good heat exchange effect according to claim 3, characterized in that, The inner tank assembly (3) also includes an inner tank body (14) and a connecting cover (15). The inner tank body (14) is fixedly installed inside the shell (1) by a fixing bracket and located directly below the preheating water tank (13). The connecting cover (15) is fixedly installed at the bottom of the inner tank body (14). The main energy-saving fire tube (7) is fixedly installed inside the inner tank body (14), and the bottom end of the main energy-saving fire tube (7) passes through the inner tank body (14) and communicates with the connecting cover (15). The connecting cover (15) is fixedly connected to the fire drain (5). The input end of the water pump (8) is fixedly connected to and communicates with the preheating water tank (13). The output pipe (9) is fixedly connected to and communicates with the surface of the inner tank body (14).

5. The energy-saving fire tube for a steam boiler with good heat exchange effect according to claim 4, characterized in that, A fixed cover (16) is fixedly installed on the top of the inner tank body (14). The top end of the main energy-saving fire tube (7) passes through the inner tank body (14) and is connected to the fixed cover (16). The preheating water tank (13) is built inside the fixed cover (16). A fan (17) is fixedly installed on the top of the fixed cover (16). The two ends of the preheating energy-saving fire tube (6) are connected to the inside of the fixed cover (16).

6. The energy-saving fire tube for a steam boiler with good heat exchange effect according to claim 5, characterized in that, The preheating energy-saving fire tube (6) and the main energy-saving fire tube (7) are internally fixed with flow guide ribs (18).

7. The energy-saving fire tube for a steam boiler with good heat exchange effect according to claim 6, characterized in that, The preheating energy-saving fire tube (6) and the main energy-saving fire tube (7) extend in a cylindrical spiral shape along the central axis.

8. The energy-saving fire tube for a steam boiler with good heat exchange effect according to claim 7, characterized in that, The preheating energy-saving fire tube (6) and the main energy-saving fire tube (7) are high-temperature corrosion resistant seamless steel pipes.

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