Waste heat recovery system of industrial furnace

Abstract

The utility model discloses a waste heat recovery system of an industrial furnace, which comprises a heating furnace used for carrying out heat treatment on a steel belt and provided with a smoke exhaust pipe used for exhausting high-temperature smoke; the heated device comprises a liquid inlet pipe, a liquid storage tank and a liquid discharge pipe, the liquid inlet pipe is communicated with the liquid storage tank, the liquid inlet pipe is used for injecting cleaning liquid into the liquid storage tank, the cleaning liquid is filled in the liquid storage tank, the liquid discharge pipe is communicated with the liquid storage tank, and the liquid discharge pipe is used for conveying the heated cleaning liquid in the liquid storage tank to water consuming equipment; the heat exchange device comprises an air inlet pipe, a heat exchange pipe and an exhaust pipe, one end of the air inlet pipe is communicated with the smoke exhaust pipe, the other end of the air inlet pipe is communicated with an air inlet of the heat exchange pipe, the heat exchange pipe is arranged in the liquid storage tank, the exhaust pipe is communicated with an air outlet of the heat exchange pipe, the air inlet pipe is provided with an automatic adjusting valve, and the automatic adjusting valve is used for adjusting the air flow of the air inlet pipe. Heat of high-temperature flue gas can be utilized, it is ensured that the temperature of cleaning liquid is within the required range, and the temperature of the cleaning liquid is controllable.

Description

Technical Field

[0001] The utility model relates to the technical field of industrial waste heat recovery and utilization, and particularly relates to a waste heat recovery system for an industrial furnace. Background Art

[0002] In the production of steel strips, heat treatment of the steel strips is required, such as annealing treatment. The steel strips are placed in an industrial furnace, and the industrial furnace heats up the steel strips. The purpose is to improve the organizational structure and performance of the steel strips.

[0003] Generally, burners are configured inside the industrial furnace. The burners are connected to gas pipelines. Gas is transported to the burners through the gas pipelines. The burners are ignited and burned to heat the steel strips in the furnace. During the heating process, high-temperature flue gas is generated. Most of the high-temperature flue gas is directly discharged into the atmosphere without being utilized. The flue gas of the industrial furnace contains a large amount of heat.

[0004] In some steel strip production processes, heat energy needs to be utilized. For example, in the steel strip cleaning process, it is required that the cleaning liquid for cleaning the steel strips has a relatively high temperature and the temperature of the cleaning liquid is within a certain range. Therefore, a waste heat recovery system is needed to recover the heat of the high-temperature flue gas discharged from the industrial furnace and use this heat to heat the cleaning liquid.

[0005] However, the existing waste heat recovery system directly recovers the high-temperature flue gas discharged from the industrial furnace. When the temperature of the flue gas is too high, the temperature of the cleaning liquid is also likely to be too high, exceeding the required temperature range for steel strip cleaning. Summary of the Utility Model

[0006] The utility model aims to at least solve one of the technical problems existing in the prior art. For this purpose, the utility model provides a waste heat recovery system for an industrial furnace, which can utilize the heat of the discharged high-temperature flue gas, heat the cleaning liquid required for steel strip cleaning with the heat of the high-temperature flue gas, and ensure that the temperature of the cleaning liquid is within the required range, realizing controllable temperature of the cleaning liquid.

[0007] According to an embodiment of the utility model, a waste heat recovery system of an industrial furnace includes: a heating furnace, which is used to perform heat treatment on a steel strip and has a smoke exhaust pipe, wherein the smoke exhaust pipe is used to discharge high-temperature smoke; a heating device, including a liquid inlet pipe, a liquid storage tank and a liquid discharge pipe, wherein the liquid inlet pipe is connected to the liquid storage tank, the liquid inlet pipe is used to inject cleaning liquid into the liquid storage tank, the liquid storage tank is filled with cleaning liquid, the liquid discharge pipe is connected to the liquid storage tank, and the liquid discharge pipe is used to transport the cleaning liquid heated in the liquid storage tank to water-using equipment; a heat exchange device, including an air inlet pipe, a heat exchange pipe and an exhaust pipe, wherein one end of the air inlet pipe is connected to the smoke exhaust pipe, and the other end of the air inlet pipe is connected to the air inlet of the heat exchange pipe, the heat exchange pipe is arranged inside the liquid storage tank, the exhaust pipe is connected to the air outlet of the heat exchange pipe, and the air inlet pipe is provided with an automatic regulating valve, and the automatic regulating valve is used to adjust the air flow rate of the air inlet pipe.

[0008] A waste heat recovery system for an industrial furnace according to an embodiment of the utility model has at least the following beneficial effects:

[0009] 1. The utility model provides an air intake pipe, a heat exchange pipe and an exhaust pipe, so that the high-temperature flue gas emitted by the heating furnace can be discharged from the exhaust pipe. The air intake pipe receives the high-temperature flue gas from the exhaust pipe. The high-temperature flue gas passes through the heat exchange pipe, and the heat exchange pipe collects the heat of the flue gas. The flue gas with reduced heat is finally discharged from the exhaust pipe, thereby realizing the collection of high-temperature flue gas, and the collection structure is simple.

[0010] 2. The utility model provides a liquid inlet pipe, a liquid storage tank and a liquid discharge pipe. The cleaning liquid is transported to the liquid storage tank through the liquid inlet pipe. The liquid storage tank contains the cleaning liquid. The heat of the heat exchange tube inside the liquid storage tank heats the cleaning liquid to make the cleaning liquid reach the required temperature. Then, the cleaning liquid is supplied to the water-using equipment through the liquid discharge pipe. Therefore, there is no need to set up a heating device to heat the cleaning liquid. The heat of the flue gas can be used to heat the cleaning liquid, which is beneficial to reduce energy consumption.

[0011] 3. The utility model sets an automatic regulating valve, which can adjust the opening of the valve according to the temperature of the cleaning liquid in the liquid storage tank, thereby adjusting the flue gas in the air intake pipe, and thus adjusting the flue gas flow of the heat exchange tube, and further adjusting the temperature change of the liquid storage tank, so as to control the cleaning liquid temperature, improve the control accuracy of the equipment, and ensure that the temperature of the cleaning liquid is within the required range.

[0012] According to a waste heat recovery system for an industrial furnace in an embodiment of the utility model, a temperature sensor is arranged inside the liquid storage tank, the temperature sensor is electrically connected to the automatic regulating valve, and the temperature sensor is used to detect the temperature of the cleaning liquid.

[0013] According to a waste heat recovery system for an industrial furnace in an embodiment of the utility model, the heat exchange tube extends in a spiral shape along the inner wall of the liquid storage tank.

[0014] A waste heat recovery system for an industrial furnace according to an embodiment of the present utility model, wherein the exhaust pipe has a main pipe and a first branch pipe connected to the main pipe. A variable frequency smoke extractor is provided on the first branch pipe. The first branch pipe is connected and communicated with the intake pipe. The variable frequency smoke extractor and the first branch pipe cooperate to extract the flue gas of the heating furnace.

[0015] A waste heat recovery system for an industrial furnace according to an embodiment of the present utility model, wherein the exhaust pipe has a second branch pipe connected to the main pipe. A switching valve is provided on the second branch pipe. The switching valve is used to control the on or off of the second branch pipe.

[0016] A waste heat recovery system for an industrial furnace according to an embodiment of the present utility model, wherein the switching valve has a rotating shaft, a blocking plate connected to the rotating shaft, and a motor for driving the rotating shaft to rotate. The rotating shaft is rotatably arranged in the second branch pipe. The blocking plate is matched with the inner surface of the second branch pipe.

[0017] A waste heat recovery system for an industrial furnace according to an embodiment of the present utility model, wherein a water pump is provided on the drain pipe. The water pump and the drain pipe cooperate to supply cleaning liquid to the water-using equipment.

[0018] A waste heat recovery system for an industrial furnace according to an embodiment of the present utility model, wherein a filter and a first pressure switch are sequentially arranged on the inlet pipe along the water flow direction.

[0019] A waste heat recovery system for an industrial furnace according to an embodiment of the present utility model, wherein a pressure gauge and a ball valve are sequentially arranged on the drain pipe along the water flow direction.

[0020] Additional aspects and advantages of the present utility model will be given in part in the following description, will become apparent in part from the following description, or will be understood through the practice of the present utility model. Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 It is a schematic structural diagram of a waste heat recovery system for an industrial furnace according to an embodiment of the present utility model;

[0023] Figure 2 is Figure 1 A schematic structural diagram of the switching valve of a waste heat recovery system for an industrial furnace shown.

[0024] Reference numerals: 100 - heating furnace, 110 - exhaust pipe, 120 - liquid inlet pipe, 130 - liquid storage tank, 140 - liquid discharge pipe, 150 - water - using equipment, 160 - air inlet pipe, 170 - heat exchange pipe, 180 - exhaust pipe, 190 - automatic regulating valve, 200 - temperature sensor, 210 - main pipeline, 220 - first branch pipeline, 230 - variable - frequency smoke extractor, 240 - second branch pipeline, 250 - on - off valve, 260 - rotating shaft, 270 - blocking plate, 280 - motor, 290 - water pump, 300 - filter, 310 - first pressure switch, 320 - pressure gauge, 330 - ball valve. Detailed implementation manners

[0025] The embodiments of the present utility model will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present utility model, and should not be construed as a limitation of the present utility model.

[0026] In the description of the present utility model, it should be understood that for the orientation description, such as the orientation or positional relationship indicated by up, down, front, back, left, right, etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present utility model.

[0027] In the description of the present utility model, the meaning of several is one or more, the meaning of multiple is two or more, greater than, less than, exceeding, etc. are understood as not including the present number, and above, below, within, etc. are understood as including the present number. If the first and the second are described, it is only for the purpose of distinguishing technical features and should not be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0028] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installed, connected and joined" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above - mentioned terms in the present utility model can be understood according to specific situations.

[0029] The waste - heat recovery system of an industrial furnace according to an embodiment of the present utility model will be described below with reference to the drawings.

[0030] Reference Figure 1 , this utility model aims to provide an embodiment of a waste heat recovery system for an industrial furnace.

[0031] In this embodiment, a waste heat recovery system for an industrial furnace mainly includes a heating furnace 100, a heating device, and a heat exchange device.

[0032] Among them, the heating furnace 100 is used for heat treatment of the steel strip and has a smoke exhaust pipe 110, and the smoke exhaust pipe 110 is used for discharging high-temperature flue gas.

[0033] In some embodiments of this utility model, the smoke exhaust pipe 110 has a main pipe 210 and a first branch pipe 220 connected to the main pipe 210. A variable frequency smoke extractor 230 is provided on the first branch pipe 220. The first branch pipe 220 is connected to the intake pipe 160 in a communicating manner, and the variable frequency smoke extractor 230 and the first branch pipe 220 cooperate to extract the flue gas of the heating furnace 100.

[0034] Therefore, the flue gas in the heating furnace 100 can enter the main pipe 210. The variable frequency smoke extractor 230 and the first branch pipe 220 extract the flue gas, so that the flue gas is introduced into the intake pipe 160. At the same time, the variable frequency smoke extractor 230 can change the power according to the intake air volume requirement of the intake pipe 160 to change the intake efficiency of the intake pipe 160 and meet the heating requirement of the cleaning liquid in the liquid storage tank 130.

[0035] In some embodiments of this utility model, the smoke exhaust pipe 110 has a second branch pipe 240 connected to the main pipe 210. A switch valve 250 is provided on the second branch pipe 240, and the switch valve 250 is used to control the conduction or closing of the second branch pipe 240.

[0036] When the flue gas of the heating furnace 100 is less, the second branch pipe 240 can be closed by using the switch valve 250, so that the flue gas can only flow into the first branch pipe 220. When the flue gas of the heating furnace 100 is more, the second branch pipe 240 can be opened by using the switch valve 250, so that the flue gas can flow into both the first branch pipe 220 and the second branch pipe 240, thereby ensuring that the temperature of the cleaning liquid in the liquid storage tank 130 is within a certain range.

[0037] In some embodiments of this utility model, reference Figure 2 , the switch valve 250 has a rotating shaft 260, a blocking plate 270 connected to the rotating shaft 260, and a motor 280 driving the rotating shaft 260 to rotate. The rotating shaft 260 is rotatably arranged in the second branch pipe 240, and the blocking plate 270 matches the inner surface of the second branch pipe 240.

[0038] Therefore, the motor 280 can be used to drive the rotation of the rotating shaft 260, so that the blocking plate 270 flips. When the blocking plate 270 is in a horizontal state, the second branch pipe 240 is in a blocked state, and the flue gas cannot pass through the second branch pipe 240. When the blocking plate 270 is in an inclined state, an exhaust passage is formed between the blocking plate 270 and the inner wall of the second branch pipe 240, and the flue gas can be discharged to the outside through the exhaust passage.

[0039] Among them, the heating device includes a liquid inlet pipe 120, a liquid storage tank 130, and a liquid discharge pipe 140. The liquid inlet pipe 120 is communicated with the liquid storage tank 130. The liquid inlet pipe 120 is used to inject cleaning liquid into the liquid storage tank 130. The liquid storage tank 130 is filled with cleaning liquid. The liquid discharge pipe 140 is communicated with the liquid storage tank 130. The liquid discharge pipe 140 is used to transport the heated cleaning liquid in the liquid storage tank 130 to the water-using device 150.

[0040] In some embodiments of the present invention, the liquid storage tank 130 is provided with a water level display, and the water level display shows the water level of the liquid storage tank 130.

[0041] In some embodiments of the present invention, a filter 300 and a first pressure switch 310 are sequentially arranged on the liquid inlet pipe 120 along the water flow direction. Therefore, the filter 300 can filter the cleaning liquid in the liquid inlet pipe 120 to make the cleaning liquid meet the use requirements. At the same time, when the water level in the liquid storage tank 130 is low, the first pressure switch 310 can be opened to enable the liquid inlet pipe 120 to inject cleaning liquid into the liquid storage tank 130.

[0042] In some embodiments of the present invention, a water pump 290 is arranged on the liquid discharge pipe 140. The water pump 290 and the liquid discharge pipe 140 cooperate to supply cleaning liquid to the water-using device 150. Thus, the liquid discharge pipe 140 can quickly transport the cleaning liquid to the water-using device 150.

[0043] In some embodiments of the present invention, a pressure gauge 320 and a ball valve 330 are sequentially arranged on the liquid discharge pipe 140 along the water flow direction. Therefore, the cleaning liquid can be transported to the water-using device 150 according to the water pressure in the liquid storage tank 130.

[0044] Among them, the heat exchange device includes an air inlet pipe 160, a heat exchange pipe 170, and an exhaust pipe 180. One end of the air inlet pipe 160 is communicated with the smoke exhaust pipe 110, and the other end of the air inlet pipe 160 is communicated with the air inlet of the heat exchange pipe 170. The heat exchange pipe 170 is arranged inside the liquid storage tank 130. The exhaust pipe 180 is communicated with the air outlet of the heat exchange pipe 170. An automatic regulating valve 190 is arranged on the air inlet pipe 160, and the automatic regulating valve 190 is used to regulate the air flow rate of the air inlet pipe 160.

[0045] In some embodiments of the present utility model, a temperature sensor 200 is disposed inside the liquid storage tank 130. The temperature sensor 200 is electrically connected to the automatic regulating valve 190, and the temperature sensor 200 is used to detect the temperature of the cleaning liquid.

[0046] Therefore, the temperature sensor 200 can be used to detect the temperature of the cleaning liquid in the liquid storage tank 130, which is convenient for the controller to control the valve opening of the automatic regulating valve 190, so that the heat exchange tube can accurately control the temperature of the cleaning liquid in the liquid storage tank 130.

[0047] In some embodiments of the present utility model, the heat exchange tube 170 extends spirally along the inner wall of the liquid storage tank 130.

[0048] Thus, the contact between the heat exchange tube 170 and the cleaning liquid in the liquid storage tank 130 can be increased, which is beneficial to better control the temperature.

[0049] Therefore, this embodiment has the following effects:

[0050] 1. By providing the intake pipe 160, the heat exchange tube 170 and the exhaust pipe 180, the high-temperature flue gas discharged from the heating furnace 100 can be discharged from the exhaust pipe 110. The intake pipe 160 receives the high-temperature flue gas from the exhaust pipe 110. The high-temperature flue gas passes through the heat exchange tube 170, and the heat exchange tube 170 collects the heat of the flue gas. The flue gas with reduced heat is finally discharged from the exhaust pipe 180. Thus, the collection of the high-temperature flue gas is realized, and the collection structure is simple.

[0051] 2. By providing the liquid inlet pipe 120, the liquid storage tank 130 and the liquid discharge pipe 140, the cleaning liquid is transported to the liquid storage tank 130 through the liquid inlet pipe 120. The liquid storage tank 130 accommodates the cleaning liquid. The heat of the heat exchange tube 170 inside the liquid storage tank 130 heats the cleaning liquid, so that the cleaning liquid obtains the required temperature. Then, the cleaning liquid is supplied to the water-using device 150 through the liquid discharge pipe 140. Thus, there is no need to additionally provide a heating device to heat the cleaning liquid, and the heat of the flue gas can be used to heat the cleaning liquid, which is beneficial to reducing energy consumption.

[0052] 3. By providing the automatic regulating valve 190, the automatic regulating valve 190 can adjust the opening of the valve of the automatic regulating valve 190 according to the temperature of the cleaning liquid in the liquid storage tank 130. Thus, the flue gas in the intake pipe 160 can be adjusted, and then the flue gas flow rate in the heat exchange tube 170 can be adjusted. Furthermore, the temperature change of the liquid storage tank 130 can be adjusted to achieve the purpose of controlling the temperature of the cleaning liquid and improving the control accuracy of the equipment, ensuring that the temperature of the cleaning liquid is within the required range.

[0053] In the description of this specification, the description referring to terms such as "one embodiment, some embodiments, illustrative embodiments, examples, specific examples or some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0054] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Various changes can be made without departing from the spirit of the present utility model within the scope of knowledge possessed by those of ordinary skill in the relevant art.

Claims

1. A waste heat recovery system for an industrial furnace, characterized in that: include: A heating furnace (100) is used for heat treatment of a steel strip and has a smoke exhaust pipe (110), wherein the smoke exhaust pipe (110) is used for exhausting high-temperature smoke; The heating device comprises a liquid inlet pipe (120), a liquid storage tank (130) and a liquid discharge pipe (140), wherein the liquid inlet pipe (120) is in communication with the liquid storage tank (130), the liquid inlet pipe (120) is used to inject cleaning liquid into the liquid storage tank (130), the liquid storage tank (130) contains cleaning liquid, and the liquid discharge pipe (140) is in communication with the liquid storage tank (130), the liquid discharge pipe (140) is used to transport the cleaning liquid heated in the liquid storage tank (130) to the water-using device (150); A heat exchange device comprises an air intake pipe (160), a heat exchange pipe (170) and an exhaust pipe (180); one end of the air intake pipe (160) is communicated with the smoke exhaust pipe (110), and the other end of the air intake pipe (160) is communicated with an air intake port of the heat exchange pipe (170); the heat exchange pipe (170) is arranged inside the liquid storage tank (130); the exhaust pipe (180) is communicated with an air outlet of the heat exchange pipe (170); the air intake pipe (160) is provided with an automatic regulating valve (190); and the automatic regulating valve (190) is used to adjust the air flow rate of the air intake pipe (160).

2. The waste heat recovery system for an industrial furnace according to claim 1, characterized in that: A temperature sensor (200) is arranged inside the liquid storage tank (130), the temperature sensor (200) is electrically connected to the automatic regulating valve (190), and the temperature sensor (200) is used to detect the temperature of the cleaning liquid.

3. The waste heat recovery system for an industrial furnace according to claim 1, characterized in that: The heat exchange tube (170) extends in a spiral shape along the inner wall of the liquid storage tank (130).

4. The waste heat recovery system for an industrial furnace according to claim 1, characterized in that: The smoke exhaust pipe (110) comprises a main pipe (210), a first branch pipe (220) connected to the main pipe (210), the first branch pipe (220) being provided with a variable frequency smoke extractor (230), the first branch pipe (220) being communicated with the air intake pipe (160), the variable frequency smoke extractor (230) and the first branch pipe (220) cooperating to extract smoke from the heating furnace (100).

5. The waste heat recovery system for an industrial furnace according to claim 4, characterized in that: The smoke exhaust pipe (110) has a second branch pipe (240) connected to the main pipe (210), and the second branch pipe (240) is provided with a switch valve (250), and the switch valve (250) is used to control the second branch pipe (240) to be turned on or off.

6. The waste heat recovery system for an industrial furnace according to claim 5, characterized in that: The switch valve (250) comprises a rotating shaft (260), a blocking plate (270) connected to the rotating shaft (260), and a motor (280) for driving the rotating shaft (260) to rotate; the rotating shaft (260) is rotatably disposed on the second branch pipe (240); and the blocking plate (270) matches the inner surface of the second branch pipe (240).

7. The waste heat recovery system for an industrial furnace according to claim 1, characterized in that: The drainage pipe (140) is provided with a water pump (290), and the water pump (290) and the drainage pipe (140) cooperate to supply cleaning liquid to the water-using equipment (150).

8. The waste heat recovery system for an industrial furnace according to claim 1, characterized in that: The liquid inlet pipe (120) is provided with a filter (300) and a first pressure switch (310) in sequence along the water flow direction.

9. The waste heat recovery system for an industrial furnace according to claim 1, characterized in that: The liquid discharge pipe (140) is provided with a pressure gauge (320) and a ball valve (330) in sequence along the water flow direction.

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