Petrochemical electrothermal furnace capable of being uniformly heated
By employing a combination structure of multiple rows of heat exchange tubes and electric heating rods in the pyrolysis furnace, and using thermocouples to control the heating power of the electric heating rods, the problem of uneven heat exchange is solved, heat exchange efficiency and energy utilization are improved, and air corrosion and environmental pollution are reduced.
Patent Information
- Application Number
- CN202511778579.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-28
- Publication Date
- 2026-01-30
Smart Images
Figure CN121422845A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of petrochemical equipment, in particular to a petrochemical electric furnace with uniform heating. BACKGROUND
[0002] The cracking furnace is the core equipment of the ethylene plant, mainly composed of the radiation section of the cracking furnace and the convection section of the cracking furnace. The convection section of the cracking furnace is the main component in the cracking furnace, which functions to recover the heat in the high-temperature flue gas to heat the cracking raw materials, boiler feed water and steam, so as to reduce the exhaust gas temperature and improve the thermal efficiency of the cracking furnace.
[0003] The convection section module is composed of the furnace wall steel structure, furnace tube, tube plate, lining and elbow box. The furnace wall steel structure mainly includes two steel walls vertically arranged and fixed together. The lining is laid on the inner surface of the two steel walls. The tube plate is vertically arranged and connected to the two steel walls on both sides. A plurality of tube plates are arranged along the width direction of the steel wall. The tube plate is provided with a plurality of tube holes. The furnace tube passes through the tube holes on the tube plate and is horizontally installed between the two steel walls. The elbow box is installed on the side of the furnace wall steel structure and has an elbow tube therein. One end of the elbow tube is connected to the furnace tube of one convection section module, and the other end is connected to the furnace tube in other convection section modules, so as to connect the furnace tubes in different layers of convection section modules to form a complete heat exchange flow channel. The upper and lower convection section modules are connected internally to form a high-temperature flue gas passage from bottom to top. The high-temperature flue gas generated by the radiation section of the cracking furnace is introduced into the high-temperature flue gas passage of the convection section of the cracking furnace above, so as to exchange heat with the heat exchange flow channel in the convection section of the cracking furnace, thereby heating the substances in the furnace tube, such as cracking raw materials, steam and boiler feed water.
[0004] The radiation section burns fuel gas, coal, gasoline and the like to generate high-temperature flue gas. However, the fuel combustion has high energy consumption and pollutes the environment. Then, the technology of electric resistance disc heating appeared. Spiral electric heating wires are arranged on the inner wall of the furnace wall to generate heat which diffuses from the inner wall of the furnace wall to the inside of the furnace body to heat the heat exchange tubes in the furnace body. The hot gas passes through the heat exchange tubes layer by layer, and the heat gradually decreases in the furnace. The temperature around the heat exchange tubes closer to the center is lower. Therefore, the heat exchange between the inner and outer heat exchange tubes is not uniform. SUMMARY
[0005] In view of all or part of the above technical problems existing in the prior art, the present application provides a petrochemical electric furnace with uniform heating.
[0006] To achieve the above-mentioned purpose, the present application provides the following technical solutions: The present application provides a petrochemical electric furnace with uniform heating, which comprises a furnace wall surrounding a furnace chamber, the inner wall of the furnace wall is provided with a heat insulation lining, and the furnace chamber is provided with a plurality of heat exchange tubes. The plurality of heat exchange tubes are arranged in multiple rows. Electric heating rods are arranged between every two adjacent rows of heat exchange tubes. The two connecting ends of the electric heating rods are arranged outside the furnace wall. The electric heating rods are arranged in parallel with the heat exchange tubes. A thermocouple is arranged between each two adjacent rows of heat exchange pipes, and the thermocouple and the electric heating rod are connected to a control module located outside the furnace chamber, and the control module controls the heating power of each row of electric heating rods according to the temperature signals fed back by the plurality of thermocouples.
[0007] As a further optional technical solution, each row of heat exchange pipes and each row of electric heating rods are arranged along a linear trajectory or a curved trajectory, and the arrangement trajectories of each row of electric heating rods and each row of heat exchange pipes are parallel.
[0008] As a further optional technical solution, each row of heat exchange pipes and each row of electric heating rods are arranged along a circular trajectory, and each row of heat exchange pipes and each row of electric heating rods are arranged in a concentric circular trajectory.
[0009] As a further optional technical solution, among the plurality of electric heating rods arranged between each two adjacent rows of heat exchange pipes: Each electric heating rod is a whole structure; or: a plurality of electric heating rods are arranged along the length direction of the heat exchange pipe.
[0010] As a further optional technical solution, the electric heating rod is a whole structure, and the thermocouple is arranged near the middle of the electric heating rod; Or: the electric heating rod is a segmented structure, and the plurality of electric heating rods corresponding to the same height of the heat exchange pipe are connected to form an electric heating group, and the thermocouples are arranged on the sides of each electric heating group.
[0011] As a further optional technical solution, a plurality of heat exchange modules are included, each heat exchange module includes the furnace wall, the heat exchange pipe and the electric heating rod, and the plurality of heat exchange modules are arranged in a vertical or horizontal stack.
[0012] As a further optional technical solution, in each row of heat exchange pipes, the end portions of the two adjacent heat exchange pipes are connected through an elbow, so that each row of heat exchange pipes is connected in series, and the end portions of the first and last heat exchange pipes in each row of heat exchange pipes are sealed and pass out of the furnace wall.
[0013] As a further optional technical solution, the furnace wall is provided with a positioning hook that hooks the elbow.
[0014] As a further optional technical solution, the electric heating rod is a graphite carbon rod.
[0015] As a further optional technical solution, the electric heating rod is an equal-diameter structure; or: the electric heating rod is a non-equal-diameter structure with a gradually changing diameter.
[0016] As a further optional technical solution, a metal petal is arranged between the two adjacent heat exchange pipes, so that the rows of heat exchange pipes are connected into a whole screen structure; and / or: the furnace chamber is a sealed cavity, and the furnace wall is provided with an inert gas input pipe connected to the furnace chamber.
[0017] The beneficial effects of the present application are: The petrochemical electric furnace of the present application is uniformly heated, compared with the prior art: multiple rows of heat exchange pipes and multiple rows of electric heating rods are distributed at intervals, and each row of heat exchange pipes has electric heating rods on both sides for heat radiation, so that the heat exchange pipes are more uniformly heated, and the heat exchange pipes on both sides are more closely heated, thereby improving the heat exchange efficiency. The space in the furnace is fully utilized, the thermal efficiency is high, and the volume can be made smaller under the same heat exchange requirement.
[0018] Furthermore, the thermocouple facilitates regional temperature monitoring, and the heating power of different electric heating rods is controlled to realize regional temperature control and make the heat exchange pipes in each region of the furnace more uniformly heated.
[0019] Further, electric heating does not require air convection required by traditional combustion, and the furnace body can be sealed to reduce air corrosion of the furnace pipes, and even inert protective gas can be filled. BRIEF DESCRIPTION OF DRAWINGS
[0020] The present application will be further described below with the help of the drawings, but the embodiments in the drawings do not constitute any limitation on the present application. For ordinary skilled in the art, other drawings can be obtained without creative labor on the basis of the following drawings.
[0021] Figure 1 It is a structural schematic view of the petrochemical electric furnace of Example 1.
[0022] Figure 2 It is a longitudinal sectional view of Figure 1 .
[0023] Figure 3 It is a partial schematic view of Figure 2 .
[0024] Figure 4 It is a transverse sectional view of Figure 1 , the viewing angle is adjusted relative to Figure 1 .
[0025] Figure 5 It is a structural schematic view of the petrochemical electric furnace of Example 2.
[0026] Figure 6 It is a longitudinal sectional view of Figure 5 .
[0027] Figure 7 It is a transverse sectional view of Figure 5 , the viewing angle is adjusted relative to Figure 5 .
[0028] Figure 8 It is a schematic view of the petrochemical electric furnace in the embodiment as a modular structure.
[0029] Figure 9 It is a schematic view of the petrochemical electric furnace in the embodiment as a transverse structure.
[0030] Reference signs: Furnace wall 1, heat insulation lining 2, heat exchange pipe 3, electric heating rod 4, elbow 5, positioning hook 6, petal 7. DETAILED DESCRIPTION
[0031] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. In the case of no conflict, the following embodiments and features in the embodiments can be combined with each other.
[0032] The petrochemical electric furnace of the embodiment one, as shown in the figure, comprises a furnace wall 1 surrounding a furnace chamber, the inner wall of the furnace wall 1 is covered with a heat insulation lining 2, and the furnace chamber is provided with a plurality of heat exchange pipes 3. Figures 1 to 7
[0033] The plurality of heat exchange pipes 3 are arranged in multiple rows, and an electric heating rod 4 arranged in a row is arranged between each two adjacent rows of heat exchange pipes 3, both connection ends of the electric heating rod 4 are led out of the furnace wall 1, and the electric heating rod 4 is distributed in parallel with the heat exchange pipes 3. The electric heating rod 4 can be selected as a graphite carbon rod.
[0034] As shown in the figure, each row of heat exchange pipes 3 and each row of electric heating rods 4 are arranged along a straight trajectory, and the arrangement trajectories of each row of electric heating rods 4 and each row of heat exchange pipes 3 are parallel. As for the most side heat exchange pipes 3, the electric heating rod 4 can be further arranged inside the heat insulation lining 2 to heat the most side heat exchange pipes 3. Figures 1 to 4 Of course, in actual application, each row of heat exchange pipes 3 and each row of electric heating rods 4 can be arranged along a curved trajectory.
[0035] As shown in the figure, the petrochemical electric furnace of the embodiment two, each row of heat exchange pipes 3 and each row of electric heating rods 4 are arranged along a circular trajectory, and each circle of heat exchange pipes 3 and each circle of electric heating rods 4 are arranged in sequence and at intervals along a concentric circular trajectory. It can be seen that the innermost circle is a circle of electric heating rods 4, the second circle is a circle of heat exchange pipes 3, the third circle is a circle of electric heating rods 4, and so on.
[0036] Figures 5 to 7 In each row of heat exchange pipes 3 of the above two embodiments, the end portions of the two adjacent heat exchange pipes 3 are connected through an elbow 5, so that each row of heat exchange pipes 3 are connected in series, and the end portions of the first and last heat exchange pipes 3 in each row of heat exchange pipes 3 are sealingly led out of the furnace wall 1. In actual application, each row of heat exchange pipes 3 can independently circulate the medium, or the rows of heat exchange pipes 3 can be connected together. The furnace wall 1 is provided with a positioning hook 6 for hooking the elbow, which improves the structural stability.
[0037]
[0038] The petrochemical electric heating furnace of the present application is provided with thermocouples (not shown in the figure, which is a commonly used temperature measuring element in temperature measuring instruments, directly measuring temperature and converting the temperature signal into a thermoelectric electromotive force signal) between each two adjacent rows of heat exchange pipes 3, the thermocouples and the electric heating rods 4 are connected to the control module outside the furnace chamber through cables, and the control module controls the heating power of each row of electric heating rods 4 according to the temperature signals fed back by the thermocouples.
[0039] In the above two embodiments, each electric heating rod 4 is an integral structure, and the two ends of each electric heating rod 4 are sealed and pass through the top and bottom of the furnace wall 1. In practice, the electric heating rods 4 in the same row are connected in series / parallel, and the control module controls the heating power of each row of electric heating rods 4 by changing the current / voltage value. The thermocouples are preferably arranged near the middle of the heat exchange pipes 3. When the temperature is lower than the preset range, the heating power of the electric heating rods 4 in the row is increased; when the temperature is higher than the preset range, the heating power of the electric heating rods 4 in the row is decreased, thereby achieving uniformity of the temperature in the electric heating furnace. Here, temperature control refers to controlling the temperature within a range, not a certain value.
[0040] Metal petals 7 are provided between adjacent two heat exchange pipes 3, so that the rows of heat exchange pipes 3 are connected into a whole screen structure, reducing the heat flow between the rows of heat exchange pipes 3 and making it easier to control the temperature field in different areas.
[0041] In practice, each row of electric heating rods 4 can be divided into sections along the length of the heat exchange pipes 3, and the electric heating rods 4 in the same height of the heat exchange pipes 3 are connected to form an electric heating group. In this way, between adjacent two rows of heat exchange pipes 3, along the length of the heat exchange pipes 3, there are multiple electric heating groups. Thermocouples are provided on the sides of each electric heating group. The control module controls the heating power of each electric heating group (by adjusting the current / voltage). The sectional structure is more suitable for longer heat exchange pipes 3.
[0042] In practice, the electric heating rods 4 can be of equal diameter, so that the heating capacity of the same electric heating rod 4 is basically the same, and the vertical arrangement of the electric heating rods 4 is longitudinally heated everywhere.
[0043] Considering that hot air always has the property of flowing upwards, heat is concentrated upwards, and the electric heating rods 4 are of non-equal diameter structure with upward diameter grading or gradual change. Under the same current / voltage, the different thicknesses of the same electric heating rod 4 make the heating capacity of the electric heating rod 4 decrease upwards, the lower part has a large heating degree, and the upper part has a small heating degree but the hot air is concentrated, achieving more uniformity from top to bottom.
[0044] In this embodiment, the furnace chamber is a sealed cavity, and the furnace wall 1 is provided with an inert gas input pipe communicating with the furnace chamber, and inert gas is introduced to reduce the corrosion of air on the surface of the heat exchange pipes 3.
[0045] As Figure 1 and Figure 5 shown is a vertical arrangement of the petrochemical electric heating furnace, the furnace wall is an integral whole, the heat exchange pipes are vertically arranged, extending from the bottom to the top of the furnace chamber, and the electric heating rods vertically penetrate the furnace wall. In practice, it can be changed to a horizontal petrochemical electric heating furnace as shown in Figure 9 , that is, the furnace wall is horizontally arranged, the heat exchange pipes are arranged left and right in the furnace chamber, and the electric heating rods penetrate the furnace wall left and right.
[0046] In practice, the electric heating furnace can also be a modular structure, the entire electric heating furnace includes a plurality of heat exchange modules 8, each heat exchange module 8 includes the furnace wall, the heat exchange pipe and the electric heating rod, as shown in Figure 8 , a plurality of heat exchange modules 8 are horizontally stacked, and the furnace walls of different heat exchange modules 8 are sealingly fixed via flanges. Of course, in practice, the plurality of heat exchange modules can be vertically stacked. The heat exchange pipes in different heat exchange modules can be connected to each other via pipes after penetrating out of the corresponding furnace walls, and the electric heating rods of different heat exchange modules can be independent of each other, or can be connected in series / parallel, which is convenient for centralized control.
[0047] In the description of the present application, it is obvious that the described embodiments are only a part of the embodiments of the present application, not all the embodiments. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.
[0048] Therefore, the above detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.
[0049] In the description of the present application, it should be noted that the terms "middle", "upper", "lower", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly used when the product is used, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second" and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance.
[0050] In the description of the application, it should be noted that unless otherwise explicitly specified and limited, the terms "set", "connected", "connected" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected. It can be mechanically connected or electrically connected. It can be directly connected or indirectly connected through an intermediate medium. It can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.
Claims
1. A petrochemical electric heating furnace with uniform heating, comprising a furnace wall enclosing a furnace chamber, an inner wall of the furnace wall being provided with a heat insulation lining, the furnace chamber being provided with a plurality of heat exchange pipes, characterized in that: the plurality of heat exchange pipes are arranged in multiple rows, and an electric heating rod is arranged between each two adjacent rows of heat exchange pipes, both connection ends of the electric heating rod penetrating out of the furnace wall, the electric heating rod being arranged in parallel with the heat exchange pipes; a thermocouple is arranged between each two adjacent rows of heat exchange pipes, the thermocouple and the electric heating rod being connected to a control module located outside the furnace chamber, the control module controlling the heating power of each row of electric heating rods according to temperature signals fed back by the plurality of thermocouples. Each row of heat exchange pipes and each row of electric heating rods are arranged along a linear track or a curved track, and the arrangement tracks of each row of electric heating rods are parallel to those of each row of heat exchange pipes. Each row of heat exchange pipes and each row of electric heating rods are arranged along a circular track, and each row of heat exchange pipes and each row of electric heating rods are arranged in a concentric circular track.
2. A petrochemical electric furnace which is heated uniformly according to claim 1, characterized in that: Each of the plurality of electric heating rods arranged between each two adjacent rows of heat exchange pipes is: an integral structure; or: a plurality of electric heating rods arranged along the length direction of the heat exchange pipes.
3. A petrochemical electric furnace which is heated uniformly according to claim 1, characterized in that:
5. The petrochemical electric heating furnace with uniform heating according to claim 4, characterized in that: when the electric heating rod is an integral structure, the thermocouple is arranged near the middle of the electric heating rod; or: when the electric heating rod is a segmented structure, and a plurality of electric heating rods corresponding to the same height of the heat exchange pipes are connected to form an electric heating group, a thermocouple is arranged on the side of each electric heating group.
4. A petrochemical electric furnace which is heated uniformly according to claim 2 or 3, characterized in that: The furnace comprises a plurality of heat exchange modules, each heat exchange module comprising the furnace wall, the heat exchange pipes and the electric heating rods, and the plurality of heat exchange modules are arranged in a vertical or horizontal stack. In each row of heat exchange pipes, the end portions of two adjacent heat exchange pipes are connected via an elbow, so that each row of heat exchange pipes is connected in series, and the end portions of the first and last heat exchange pipes in each row of heat exchange pipes penetrate out of the furnace wall in a sealed manner. The electric heating rod is a graphite carbon rod. The electric heating rod is an equal-diameter structure; or: the electric heating rod is a non-equal-diameter structure with a gradually changing diameter. A metal petal is arranged between two adjacent heat exchange pipes, so that the heat exchange pipes are connected into a whole screen structure; and / or: the furnace chamber is a sealed cavity, and the furnace wall is provided with an inert gas input pipe communicating with the furnace chamber.
6. A petrochemical electric furnace which is heated uniformly according to claim 5, characterized in that: 7. A petrochemical electric furnace which is heated uniformly according to claim 2 or 3, characterized in that: 8. A petrochemical electric furnace which is heated uniformly according to claim 1, characterized in that: 9. A petrochemical electric furnace which is heated uniformly according to claim 1 or 8, characterized in that: 10. A petrochemical electric furnace which is heated uniformly according to claim 1, characterized in that: