A waste heat recovery device and a hot rolling production line

Abstract

The present application discloses a waste heat recovery device and a hot rolling production line, relating to the field of metallurgical technology. The waste heat recovery device is used to recover the waste heat in hot rolled steel and includes a heat exchange chamber. The hot rolled steel exchanges heat with the gas in the heat exchange chamber to form a heat energy gas. A material conveying port is provided at the end of the heat exchange chamber, and the material conveying port is used for the hot rolled steel to enter and exit the heat exchange chamber. A sealing mechanism is provided at the material conveying port, and the sealing mechanism is used to close or open the material conveying port. The hot rolling production line includes the waste heat recovery device described above. The waste heat recovery device provided by the present application can achieve a high recovery rate of the waste heat in hot rolled steel to achieve the effect of energy conservation.

Description

Technical Field

[0001] The present application relates to the technical field of metallurgy, and particularly to a waste heat recovery device and a hot rolling production line. Background Art

[0002] In the metallurgical industry, energy consumption accounts for a relatively large proportion of the product cost. The coiling temperature of hot-rolled stainless steel is generally 800°C. After coiling, the steel coil is transported to the finished product bay through a collecting device for air cooling or placed in a slow cooling pit for slow cooling, resulting in a large amount of high-quality heat contained in the steel coil being directly dissipated into the air, thus causing energy waste.

[0003] However, the existing waste heat recovery devices have serious problems of heat dissipation, resulting in low waste heat recovery rates. Summary of the Invention

[0004] The present application provides a waste heat recovery device and a hot rolling production line, which can recover the waste heat in hot-rolled steel to save energy.

[0005] To solve the above problems, the present application provides:

[0006] A waste heat recovery device for recovering the waste heat in hot-rolled steel, including a heat exchange chamber, wherein the hot-rolled steel exchanges heat with the gas in the heat exchange chamber to form a heat energy gas;

[0007] A material conveying port is provided at the end of the heat exchange chamber, and the material conveying port is used for the hot-rolled steel to enter and exit the heat exchange chamber; a sealing mechanism is provided at the material conveying port, and the sealing mechanism is used to close or open the material conveying port.

[0008] In a possible implementation manner, the sealing mechanism includes a sealing door unit and an air sealing unit; the air sealing unit is arranged on the side of the sealing door unit close to the inside of the heat exchange chamber;

[0009] The sealing door unit is used to mechanically close the material conveying port; the air sealing unit is used to form a positive pressure air flow at the material conveying port to block the outward flow of the gas in the heat exchange chamber.

[0010] In a possible implementation manner, the air sealing unit includes two groups of high-pressure air nozzles, and the two groups of high-pressure air nozzles are arranged oppositely;

[0011] When the sealing mechanism closes the material conveying port, the two groups of high-pressure air nozzles are respectively arranged on opposite sides of the material conveying port; the high-pressure air nozzles are used to connect to a compressed air gas source to form a positive pressure air flow at the material conveying port.

[0012] In a possible implementation, the sealing door unit includes a sealing door and a lifting assembly, and the lifting assembly is used to drive the sealing door to lift so as to close or open the material conveying port.

[0013] In a possible implementation, the sealing door unit further includes a pressing assembly, and the pressing assembly is used to push the sealing door to move in a direction close to the heat exchange chamber.

[0014] In a possible implementation, the pressing assembly includes a counterweight, a mounting bracket, and a connecting rod; the mounting bracket is fixedly installed on a side of the sealing door away from the air sealing unit; the counterweight is swingably installed on the mounting bracket through the connecting rod;

[0015] The vertical distance from the connection point of the connecting rod and the mounting bracket to the sealing door is less than the vertical distance from the center of gravity of the counterweight to the sealing door.

[0016] In a possible implementation, a plurality of flow guiding plates are further arranged at intervals in the heat exchange chamber, and the flow guiding plates are used to guide the air flow in the heat exchange chamber.

[0017] In a possible implementation, the waste heat recovery device further includes a material conveying mechanism for feeding hot rolled steel into or out of the heat exchange chamber;

[0018] The material conveying mechanism includes a track, a moving trolley, and a driving member, and the driving member is used to drive the moving trolley to move along the track.

[0019] In a possible implementation, a limiting bracket is arranged on the moving trolley, and the limiting bracket is used to limit the hot rolled steel.

[0020] On the other hand, the present application provides a hot rolling production line including the waste heat recovery device described above.

[0021] The beneficial effects of the present application are as follows: The present application provides a waste heat recovery device, including a heat exchange chamber, and a material conveying port is arranged at an end of the heat exchange chamber for hot rolled steel to enter and exit the heat exchange chamber; a sealing mechanism is arranged at the material conveying port, and the sealing mechanism is used to seal or open the material conveying port.

[0022] During the production process of hot-rolled steel, the formed hot-rolled steel can be transferred to the heat exchange chamber through the material conveying port. Subsequently, the material conveying port can be sealed by a sealing mechanism, thereby avoiding heat exchange between the air inside and outside the heat exchange chamber. After the hot-rolled steel exchanges heat with the air in the heat exchange chamber, the low-temperature gas in the heat exchange chamber becomes high-temperature gas, that is, heat energy gas. The generated heat energy gas can be reused. Exemplarily, the heat energy gas can be introduced into a heat pipe waste heat boiler to exchange heat with water. After the water absorbs heat, corresponding medium-pressure steam and low-pressure steam are generated. Among them, the medium-pressure steam can be used for thermal power generation, and the low-pressure steam can be used for the thermal deaeration of the heat pipe waste heat boiler itself. Thus, the recovery and utilization of the waste heat in the formed hot-rolled steel are realized, thereby achieving the purpose of saving energy, that is, the purpose of energy conservation in the hot-rolling production process. At the same time, the setting of the sealing mechanism can prevent the heat in the heat exchange chamber from dissipating outward, thereby improving the recovery rate of the waste heat in the hot-rolled steel. Brief Description of the Drawings

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation of the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 Shows a top view structural schematic diagram of a waste heat recovery device;

[0025] Figure 2 Shows a side view structural schematic diagram of a waste heat recovery device;

[0026] Figure 3 Shows a partial structural schematic diagram of a sealing mechanism;

[0027] Figure 4 Shows a structural schematic diagram of a sealing door unit;

[0028] Figure 5 Shows a structural schematic diagram of a sealing door installed in a heat exchange chamber;

[0029] Figure 6 Shows a force diagram between a pressing assembly and a sealing door.

[0030] Main Element Symbol Explanation:

[0031] 1 - Heat exchange chamber; 11 - Housing; 12 - Material conveying port; 121 - Material input port; 122 - Material output port; 13 - Exhaust port; 14 - Cover plate; 2 - Sealing mechanism; 21 - Sealing door unit; 211 - Sealing door; 212 - Lifting assembly; 212a - Hoist; 212b - Steel wire rope; 213 - Pressing assembly; 213a - Counterweight; 213b - Mounting seat; 213c - Connecting rod; 213d - Mounting frame; 22 - Air sealing unit; 221 - Sealing curtain; 222 - High-pressure air nozzle; 223 - Gap; 3 - Gas conveying mechanism; 4 - Deflector; 5 - Material conveying mechanism; 51 - Track; 52 - Moving trolley; 521 - Limit bracket; 53 - Driving member; 6 - Hoisting mechanism; 7 - Compressed air gas source; 8 - Waste heat utilization device; 9 - Hot rolled steel. Detailed implementation manners

[0032] The embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals indicate the same or similar elements or elements with the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and should not be construed as a limitation to the present application.

[0033] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present application 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 to the present application.

[0034] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality" means two or more unless otherwise specifically defined.

[0035] In this application, unless otherwise clearly defined and limited, terms such as "installation", "connection", "linkage", "fixation", etc. shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0036] In this application, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature can be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature can be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0037] Embodiment 1

[0038] In the embodiment, a waste heat recovery device is provided, which can be used in the production of hot-rolled steel, and can recover the waste heat of the hot-rolled steel 9 itself, so as to achieve the effects of energy recovery and utilization and energy saving, and solve the problem of energy waste in the production process of hot-rolled steel.

[0039] As Figure 1 and Figure 2 shown, the waste heat recovery device includes a heat exchange chamber 1. A material conveying port 12 is provided at the end of the heat exchange chamber 1 to facilitate the entry and exit of materials from the material conveying port 12 into and out of the heat exchange chamber 1. Among them, the material can be the hot-rolled steel 9; specifically, the material can be a hot-rolled stainless steel coil after hot-rolling and coiling. The hot-rolled steel 9 can exchange heat with the gas in the heat exchange chamber 1 to form a heat energy gas.

[0040] Of course, in some other embodiments, the hot-rolled steel 9 can also be hot-rolled steel materials such as steel strips after hot-rolling.

[0041] A sealing mechanism 2 is also provided at the material conveying port 12, and the sealing mechanism 2 is used to close or open the material conveying port 12. It can be understood that when the hot-rolled steel 9 enters and exits the heat exchange chamber 1, the sealing mechanism 2 opens the material conveying port 12. When the hot-rolled steel 9 is exchanging heat in the heat exchange chamber 1, the sealing mechanism 2 can close the material conveying port 12 to avoid heat dissipation.

[0042] During the production process, the sealing mechanism 2 opens the material conveying port 12, and the hot-rolled steel 9 at a relatively high temperature can be fed into the heat exchange chamber 1 through the material conveying port 12. Subsequently, the sealing mechanism 2 closes the material conveying port 12 to seal the heat exchange chamber 1, thereby preventing the air flow in the heat exchange chamber 1 from leaking out through the material conveying port 12, and further preventing heat from leaking out. Inside the heat exchange chamber 1, the hot-rolled steel 9 exchanges heat with the gas in the heat exchange chamber 1 to transfer the heat energy from the hot-rolled steel 9 to the gas in the heat exchange chamber 1. Thus, the temperature of the low-temperature gas in the heat exchange chamber 1 gradually rises, becoming a gas with a relatively high temperature, forming a heat energy gas carrying heat energy; at the same time, the temperature of the hot-rolled steel 9 itself gradually decreases to achieve a cooling effect. When the heat exchange of the hot-rolled steel 9 located in the heat exchange chamber 1 is completed, the hot-rolled steel 9 in the heat exchange chamber 1 can be replaced to carry out the waste heat recovery of the next group of hot-rolled steel 9, and the cooled hot-rolled steel 9 can be sent to the finished product bay for storage.

[0043] During the heat exchange process, the generated heat energy gas with a relatively high temperature can be recycled. Exemplarily, the heat energy gas can be introduced into a heat pipe waste heat boiler to exchange heat with water. After the water absorbs heat, medium-pressure steam and low-pressure steam are generated accordingly. Among them, the medium-pressure steam can be used for thermal power generation, and the low-pressure steam can be used for the thermal deaeration of the heat pipe waste heat boiler itself. Thus, the waste heat in the hot-rolled steel 9 is recycled, that is, the energy is recycled to improve the energy utilization rate. At the same time, the effect of saving energy can also be achieved, saving the energy consumption in the production process of hot-rolled steel. Through the setting of the sealing mechanism 2, the heat in the heat exchange chamber 1 can be prevented from dissipating outward, thereby improving the waste heat recovery rate of the waste heat recovery device.

[0044] In summary, the waste heat recovery device provided by the present application can recycle the waste heat in the hot-rolled steel 9 to achieve energy conservation, reduce the energy consumption in the production process of hot-rolled steel, and at the same time has a relatively high waste heat recovery rate.

[0045] Embodiment 2

[0046] An embodiment provides a waste heat recovery device. It can be understood that this embodiment is a further improvement based on Embodiment 1.

[0047] As Figure 1 and Figure 2 shown, the heat exchange chamber 1 includes a housing 11, and the interior of the housing 11 is the space where the hot-rolled steel 9 exchanges heat with the low-temperature gas.

[0048] In some embodiments, the housing 11 may include a steel shell and heat-insulating materials filled inside the steel shell. Thus, the heat-insulating effect of the housing 11 is achieved, ensuring that the heat inside the housing 11 will not dissipate outward, that is, ensuring that the heat exchange chamber 1 is in an adiabatic state with the external environment, and improving the waste heat recovery rate.

[0049] Exemplarily, the heat-insulating material filled inside the housing 11 can be selected from materials such as polyurethane foam, glass wool, foamed cement, and rock wool.

[0050] In the embodiment, a detachable cover plate 14 is further provided at the top of the housing 11 for closing the top of the housing 11. When a failure occurs in the waste heat recovery device, the cover plate 14 can be opened by a hoisting device, and the hot-rolled steel 9 located inside the housing 11 can be hoisted out, so as to facilitate maintenance after the temperature inside the housing 11 decreases.

[0051] In the embodiment, the material conveying port 12 can be arranged at the end of the housing 11 in the horizontal direction. Specifically, the material conveying port 12 can be arranged at the end position in the length direction of the housing 11. The material conveying port 12 includes a material input port 121 and a material output port 122 which are oppositely arranged. Thus, the hot-rolled steel 9 with a relatively high temperature can enter the heat exchange chamber 1 from the material input port 121, and the cooled hot-rolled steel 9 can be sent out of the heat exchange chamber 1 from the material output port 122, realizing the one-way conveying of the hot-rolled steel 9 and improving the production efficiency.

[0052] Correspondingly, a sealing mechanism 2 is provided at each of the positions of the material input port 121 and the material output port 122 for closing or opening the corresponding material input port 121 and material output port 122. In some specific embodiments, the structures of the two groups of sealing mechanisms 2 are the same, and one of them will be introduced below.

[0053] As Figure 3 and Figure 4 shown, the sealing mechanism 2 includes a sealing door unit 21 and an air sealing unit 22. Among them, the air sealing unit 22 is arranged on the side of the sealing door unit 21 close to the inside of the heat exchange chamber 1. Among them, the sealing door unit 21 is used to form a mechanical seal at the position of the material conveying port 12 to block the air flow inside and outside the heat exchange chamber 1. The air sealing unit 22 is used to form a positive pressure air flow at the position of the material conveying port 12, that is, a high-pressure air flow barrier, so as to push the air flow near the position of the material conveying port 12 inside the heat exchange chamber 1 to move towards the middle of the heat exchange chamber 1, further avoiding the leakage of the heat inside the heat exchange chamber 1 to the outside of the heat exchange chamber 1.

[0054] As Figure 4 and Figure 5 shown, specifically, the sealing door unit 21 includes a sealing door 211 and a lifting assembly 212. Among them, the lifting assembly 212 is installed at the top of the heat exchange chamber 1 and is arranged corresponding to the upper part of the material conveying port 12. The lifting assembly 212 is connected to the sealing door 211, so that the sealing door 211 is driven by the lifting assembly 212 to move up and down to close or open the material conveying port 12.

[0055] It can be understood that when the lifting assembly 212 drives the sealing door 211 to rise above the material conveying port 12, that is, the sealing door 211 is vertically misaligned with the material conveying port 12, the material conveying port 12 is opened. When the sealing door 211 moves downward to correspond to the material conveying port 12, the material conveying port 12 is closed.

[0056] Among them, the lifting assembly 212 may include a winch 212a and a steel wire rope 212b. One end of the steel wire rope 212b is wound around the winch 212a, and the other end of the steel wire rope 212b is fixedly connected to the top of the sealing door 211. The lifting of the sealing door 211 is realized by the winch 212a taking in and releasing the steel wire rope 212b.

[0057] In some other embodiments, the lifting assembly 212 may also select a hoisting device such as an electric hoist.

[0058] As Figure 4 shown, the sealing door unit 21 further includes a pressing assembly 213 for pushing the sealing door 211 in the direction close to the heat exchange chamber 1. The pressing assembly 213 is installed on the side of the sealing door 211 away from the heat exchange chamber 1, and the pressing assembly 213 moves up and down synchronously with the sealing door 211.

[0059] Specifically, the pressing assembly 213 includes a counterweight 213a, a connecting rod 213c, and a mounting bracket 213d. Among them, the mounting bracket 213d is fixedly installed on the side of the sealing door 211 away from the heat exchange chamber 1. One end of the connecting rod 213c is connected to the counterweight 213a. The other end of the connecting rod 213c is swingably installed on the mounting bracket 213d through a mounting seat 213b, so that the counterweight 213a can approach or move away from the sealing door 211.

[0060] As Figure 6 shown, among them, the vertical distance from the connection point of the connecting rod 213c and the mounting bracket 213d to the sealing door 211 is less than the vertical distance from the center of gravity of the counterweight 213a to the sealing door 211. Thus, the pulling force F of the connecting rod 213c on the counterweight 213a is an inclined upward force. To keep the counterweight 213a in force balance, the pulling force F can be decomposed into a vertically upward force F1 and a horizontal force F2, and the force F2 is directed towards the sealing door 211. Thus, a horizontal thrust F'2 can be exerted on the sealing door 211 by the counterweight 213a to push the sealing door 211 in the direction close to the heat exchange chamber 1, so as to ensure that the sealing door 211 can closely lean against the position of the material conveying port 12 of the heat exchange chamber 1 and avoid heat leakage caused by the separation of the sealing door 211 from the material conveying port 12.

[0061] In some embodiments, two sets of pressing components 213 may be arranged in parallel, with one set of pressing components 213 pressing on the other set of pressing components 213 to provide a greater pressing force on the sealing door 211, further ensuring that the sealing door 211 closes the material conveying port 12.

[0062] In an embodiment, the sealing door 211 may be formed by welding a section steel and a steel plate. Of course, in some specific embodiments, the inside of the sealing door 211 may also be filled with a heat-insulating material to achieve the effect of heat insulation.

[0063] Furthermore, as Figure 3 shown, the air sealing unit 22 includes two spaced sealing curtains 221 and two sets of oppositely arranged high-pressure nozzles 222. Specifically, the sealing curtain 221 is fixedly installed on the side of the sealing door 211 close to the heat exchange chamber 1, and the sealing curtain 221 is annular and is arranged around the edge of the sealing door 211. When the sealing mechanism 2 closes the material conveying port 12, the sealing curtain 221 abuts against the housing 11 of the heat exchange chamber 1, and the sealing curtain 221 is correspondingly arranged around the circumference of the material conveying port 12. A gap 223 is provided between the two sealing curtains 221, and the high-pressure nozzles 222 are installed in the gap 223 between the two sealing curtains 221.

[0064] In some specific embodiments, the material conveying port 12 may be a rectangular opening. Correspondingly, the sealing curtain 221 is also a rectangular ring. The two sets of high-pressure nozzles 222 may be correspondingly arranged on the upper and lower sides of the sealing curtain 221, and the two sets of high-pressure nozzles 222 are oppositely arranged, that is, the air flows generated by the two sets of high-pressure nozzles 222 are in countercurrent to each other.

[0065] Of course, in some other embodiments, the two sets of high-pressure nozzles 222 may also be correspondingly arranged on the two side edges of the sealing curtain 221, that is, the left side edge and the right side edge.

[0066] As Figure 1 shown, both sets of high-pressure nozzles 222 can be connected to a compressed air source 7 through hoses to supply compressed air to the high-pressure nozzles 222. Thus, when the sealing mechanism 2 closes the material conveying port 12, a high-pressure air flow barrier that convects up and down can be formed at the position of the material conveying port 12 by the two sets of high-pressure nozzles 222 to block the high-temperature gas in the heat exchange chamber 1 from overflowing outward.

[0067] In some other embodiments, the air sealing unit 22 may also be directly fixedly installed at the outer edge position of the material conveying port 12.

[0068] In some specific embodiments, the sealing curtain 221 may be made of a high-chromium nickel austenitic stainless steel mesh chain structure with a refractory fiber cloth lining filled inside.

[0069] It is understandable that the waste heat recovery device may further include a control mechanism (not shown in the figure) for controlling the operation of each mechanism of the waste heat recovery device. Among them, the lifting assembly 212 and the high-pressure nozzle 222 of the sealing mechanism 2 can both be electrically connected to the control mechanism, and the control mechanism controls the operation of the lifting assembly 212 and the high-pressure nozzle 222. Of course, the high-pressure nozzle 222 can be selected as a high-pressure nozzle with an electric control valve.

[0070] In some other embodiments, the waste heat recovery device can also be directly electrically connected to the main control mechanism of the hot rolling production line, and the main control mechanism of the hot rolling production line conducts unified control.

[0071] As Figure 1 shown, further, the heat exchange chamber 1 is also connected with a gas transmission mechanism 3 for supplying low-temperature gas into the heat exchange chamber 1. Correspondingly, an exhaust port 13 is also provided on the heat exchange chamber 1 for discharging the gas at a higher temperature after heating up in the heat exchange chamber 1.

[0072] In some specific embodiments, the gas transmission mechanism 3 can be selected as a blower, and the output end of the blower is communicated with the inside of the heat exchange chamber 1 to convey low-temperature gas into the heat exchange chamber 1, and the gas transmission mechanism 3 is electrically connected to the control mechanism. At the same time, the gas transmission mechanism 3 can also be used as a power source to promote the flow of the gas in the heat exchange chamber 1, so that the gas at a higher temperature after heating up flows in the direction of the exhaust port 13 and is discharged through the exhaust port 13. Among them, the exhaust port 13 can be communicated with the waste heat utilization device 8 to reuse the recovered waste heat.

[0073] As Figure 1 shown, in some specific embodiments, the waste heat utilization device 8 can include a heat pipe waste heat boiler (not shown in the figure). In the heat pipe waste heat boiler, the heat energy gas exchanges heat with water, and the water absorbs heat to generate corresponding medium-pressure steam and low-pressure steam. Among them, the medium-pressure steam can be used for thermal power generation, and the low-pressure steam can be used for the thermal deaeration of the heat pipe waste heat boiler itself. Thus, multi-level utilization of waste heat recovery is realized, the waste heat recovery utilization rate is improved, and energy is saved.

[0074] In some specific embodiments, a gas transmission pipeline communicated with the gas transmission mechanism 3 is arranged in the heat exchange chamber 1. The gas transmission pipeline can be arranged around the heat exchange chamber 1, and a plurality of air outlets are arranged on the gas transmission pipeline. Thus, the low-temperature gas can be evenly fed into the heat exchange chamber 1, and the efficiency and quality of heat exchange can also be ensured.

[0075] In the heat exchange chamber 1, after the gas exchanges heat, its temperature rises. Due to thermal expansion, the gas at a higher temperature will gradually rise to the upper part of the heat exchange chamber 1, so that the gas at a higher temperature is located in the upper space of the heat exchange chamber 1, and the gas at a lower temperature is located in the lower space of the heat exchange chamber 1.

[0076] Accordingly, in some specific embodiments, the connection position between the gas delivery mechanism 3 and the heat exchange chamber 1 can be arranged near the bottom end of the heat exchange chamber 1, and the exhaust port 13 for discharging the higher temperature gas can be arranged near the top end of the heat exchange chamber 1. Thus, low temperature gas can be continuously fed from the bottom of the heat exchange chamber 1, and the low temperature gas heats up after heat exchange with the hot-rolled steel 9, and gradually moves toward the top of the heat exchange chamber 1, and then is discharged outward from the exhaust port 13. Thus, it is possible to avoid the low temperature gas from being discharged through the exhaust port 13 as much as possible, so as to ensure the quality of the output high temperature air.

[0077] Since the temperature required for coiling the hot rolled steel 9 is generally about 800°C, the temperature of the hot rolled steel 9 after coiling will also be about 700°C. When the hot rolled steel 9 first enters the heat exchange chamber 1, the temperature of the gas in the heat exchange chamber 1 can be raised to 500°C to 600°C. As the heat exchange continues, the waste heat of the hot rolled steel 9 itself gradually decreases, and when the gas entering the heat exchange chamber 1 is heat exchanged later, the temperature of the gas will also gradually decrease.

[0078] In some specific embodiments, a corresponding temperature sensor (not shown in the figure) and a solenoid valve (not shown in the figure) are provided at the exhaust port 13, and both the temperature sensor and the solenoid valve are electrically connected to the control mechanism. The temperature sensor can detect the temperature of the thermal energy gas discharged at the exhaust port 13, and the solenoid valve can be used to control the opening and closing of the exhaust port 13. During the exhaust process, when the temperature of the thermal energy gas detected by the temperature sensor is lower than 300°C, the control mechanism can control the solenoid valve to close, during which the hot rolled steel 9 in the heat exchange chamber 1 can be replaced.

[0079] like Figure 1 As shown, in the embodiment, a plurality of guide plates 4 are further provided in the heat exchange chamber 1 for guiding the airflow in the heat exchange chamber 1. Specifically, the guide plates 4 may be provided in two groups, and each group includes a plurality of guide plates 4, and the plurality of guide plates 4 in the same group may be arranged in parallel with each other. The two groups of guide plates 4 are arranged on both sides of the heat exchange chamber 1, and may be symmetrically arranged about the material conveying port 12. During operation, the guide plates 4 may allow the airflow to flow to the position where the hot-rolled steel 9 is placed, so as to facilitate heat exchange between the gas and the hot-rolled steel 9. In the embodiment, the guide plates 4 may extend from the bottom of the heat exchange chamber 1 to the top of the heat exchange chamber 1.

[0080] like Figure 1 and Figure 2 As shown, the waste heat recovery device further includes a material conveying mechanism 5 for conveying the hot-rolled steel 9 into or out of the heat exchange chamber 1 .

[0081] Specifically, the material conveying mechanism 5 includes a track 51, a moving trolley 52 and a driving member 53, and the driving member 53 is electrically connected to the control mechanism. Among them, the track 51 extends along the length direction of the heat exchange chamber 1, and the track 51 penetrates through the heat exchange chamber 1. Specifically, the track 51 is arranged along the connection line of the material input port 121 and the material output port 122, and in the heat exchange chamber 1, the track 51 passes through between the two groups of guide plates 4, and the guide plates 4 all extend towards the direction of the track 51. At the same time, the track 51 has a certain extension length outside both ends of the heat exchange chamber 1 to facilitate the loading and unloading operations.

[0082] The moving trolley 52 is slidably mounted on the track 51. The driving member 53 is connected to the moving trolley 52, and the driving member 53 is used to drive the moving trolley 52 to travel along the track 51, so as to realize the transportation of the hot rolled steel 9. In some embodiments, the driving member 53 can be a driving device such as an electric motor or a hydraulic mechanism. In this embodiment, the driving member 53 is an electric motor.

[0083] A limiting bracket 521 is further arranged on the moving trolley 52 for limiting and fixing the hot rolled steel 9 to prevent the hot rolled steel 9 from moving randomly on the moving trolley 52. In some specific embodiments, the limiting bracket 521 can be a V-shaped bracket, and the open end is arranged towards the upper part of the moving trolley 52 to facilitate putting the hot rolled steel 9 into the limiting bracket 521 and stably limiting the hot rolled steel 9.

[0084] In some other embodiments, the limiting bracket 521 can also be a U-shaped bracket or other structures.

[0085] In the embodiment, the waste heat recovery device further includes a hoisting mechanism 6 for hoisting the hot rolled steel 9. Specifically, the hoisting mechanism 6 can be used to hoist the hot rolled steel 9 with a higher temperature after hot rolling from the coiler to the moving trolley 52, and the hoisting mechanism 6 can also be used to hoist the cooled hot rolled steel 9 from the moving trolley 52 to the finished product bay for storage.

[0086] During operation, after the coiling of the hot-rolled steel coil 9 is completed, it can be lifted by the lifting mechanism 6 from the coiler to the moving trolley 52 at one end of the material input port 121. The sealing mechanism 2 at the position of the material conveying port 12 is opened, and under the drive of the driving member 53, the moving trolley 52 drives the hot-rolled steel coil 9 with a relatively high temperature into the heat exchange chamber 1. After the feeding is completed, that is, when the material conveying mechanism 5 transports a certain number of hot-rolled steel coils 9 into the heat exchange chamber 1, the sealing mechanism 2 seals the material conveying ports 12 at both ends of the heat exchange chamber 1. Inside the heat exchange chamber 1, the hot-rolled steel coil 9 exchanges heat with the gas at a relatively low temperature, and the heated gas is sent into the heat pipe waste heat boiler to exchange heat with water to generate corresponding medium-pressure steam or low-pressure steam. Among them, the medium-pressure steam can be used for thermal power generation, and the low-pressure steam can be used for thermal deaeration of the heat pipe waste heat boiler itself to realize the secondary utilization of waste heat. After the hot-rolled steel coil 9 located in the heat exchange chamber 1 completes heat exchange, the material conveying ports 12 at both ends of the heat exchange chamber 1 are opened, and under the action of the driving member 53, the moving trolley 52 continues to move forward, and the cooled hot-rolled steel coil 9 is transported out of the heat exchange chamber 1. At the same time, the hot-rolled steel coil 9 with a relatively high temperature is continuously transported into the heat exchange chamber 1 for heat exchange. Exemplarily, when the temperature sensor detects that the temperature of the discharged gas is lower than 300 °C, it can be determined that the heat exchange is completed, and then the control mechanism can control components such as the sealing mechanism 2 and the material conveying mechanism 5 to perform related actions. During the heat exchange, the lifting mechanism 6 can lift the cooled hot-rolled steel coil 9 from the position of the moving trolley 52 to the finished product bay for storage. In addition, the coiled hot-rolled steel coil 9 can continue to be lifted from the coiler to the moving trolley 52 outside one end close to the material input port 121.

[0087] Of course, in some other embodiments, the waste heat recovery device may include two sets of lifting mechanisms 6. One set of lifting mechanisms 6 can be used for lifting the hot-rolled steel coil 9 at a relatively high temperature, that is, lifting the hot-rolled steel coil 9 from the coiler to the moving trolley 52 outside one end close to the material input port 121. The other set of lifting mechanisms 6 can be used for lifting the cooled hot-rolled steel coil 9, that is, lifting the cooled hot-rolled steel coil 9 from the moving trolley 52 outside one end close to the material output port 122 to the finished product bay for storage.

[0088] Embodiment III

[0089] The embodiment also provides a hot-rolling production line, including the waste heat recovery device provided in Embodiment I or Embodiment II.

[0090] Among them, the hot-rolling production line may further include a heating furnace, a hot-rolling mechanism, and a coiler arranged in sequence. The strip steel heated by the heating furnace is transported to the hot-rolling mechanism for hot rolling, and then sent into the coiler to be coiled into a steel coil. The hot-rolled steel coil 9 after coiling can be sent into the waste heat recovery device for waste heat recovery, and the hot-rolled steel coil 9 itself is cooled down. The cooled hot-rolled steel coil 9 can be transferred to the finished product bay for storage.

[0091] In the description of this specification, the descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean 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 application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0092] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A waste heat recovery device for recovering the waste heat in hot-rolled steel, characterized in that, It includes a heat exchange chamber, where the hot rolled steel exchanges heat with the gas in the heat exchange chamber to form a thermal energy gas; A material conveying port is provided at the end of the heat exchange chamber, and the material conveying port is used for the hot rolled steel to enter and exit the heat exchange chamber; a sealing mechanism is provided at the material conveying port, and the sealing mechanism is used to close or open the material conveying port; The sealing mechanism includes a sealing door unit, and the sealing door unit includes a sealing door, a lifting component and a pressing component. The lifting component is installed at the top of the heat exchange chamber and is connected to the sealing door. The lifting component is used to drive the sealing door to lift to close or open the material conveying port; The pressing component includes a counterweight, a mounting rack and a connecting rod; the mounting rack is fixedly installed on the side of the sealing door away from the heat exchange chamber; the counterweight is swingably installed on the mounting rack through the connecting rod, and the vertical distance from the connection point of the connecting rod and the mounting rack to the sealing door is less than the vertical distance from the center of gravity of the counterweight to the sealing door.

2. The waste heat recovery device according to claim 1, wherein The sealing mechanism further includes an air sealing unit; the air sealing unit is arranged on the side of the sealing door unit close to the interior of the heat exchange chamber; The air sealing unit is used to form a positive pressure air flow at the material conveying port to block the outward flow of the gas in the heat exchange chamber.

3. The waste heat recovery device according to claim 2, characterized in that, The air sealing unit includes two groups of high-pressure nozzles, and the two groups of high-pressure nozzles are arranged oppositely; When the sealing mechanism closes the material conveying port, the two groups of high-pressure nozzles are respectively arranged on the opposite sides of the material conveying port; the high-pressure nozzles are used to connect to a compressed air gas source to form a positive pressure air flow at the material conveying port.

4. The waste heat recovery device according to claim 1, wherein A plurality of flow guiding plates are also arranged at intervals in the heat exchange chamber, and the flow guiding plates are used to guide the air flow in the heat exchange chamber.

5. The waste heat recovery device according to claim 1, characterized in that The waste heat recovery device further includes a material conveying mechanism for feeding the hot rolled steel into or out of the heat exchange chamber; The material conveying mechanism includes a track, a moving trolley and a driving member, and the driving member is used to drive the moving trolley to move along the track.

6. The waste heat recovery device according to claim 5, characterized in that, A limiting bracket is arranged on the moving trolley, and the limiting bracket is used to limit the hot rolled steel.

7. A hot rolling production line, characterized in that, It includes the waste heat recovery device according to any one of claims 1 to 6.

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