A carbon fiber preoxidation furnace based on cooling and a preoxidation method for preparing NFs

Abstract

The invention relates to the technical field of carbon fiber preparation, and in particular to a carbon fiber preoxidation furnace based on cooling and a preoxidation method for preparing NFs; the invention comprises a frame, a furnace body arranged on the frame, and an oxidizing device horizontally fixedly arranged in the furnace body; the oxidizing device is characterized in that the oxidizing device consists of a heating module and a cooling module; the heating module is provided with a plurality of heating elements capable of heating carbon fibers; the cooling module is provided with a regulating medium capable of continuously passing through the heating elements and capable of regulating the temperature of the heating elements; the air cooling module is vertically arranged below the cooling module for air cooling the heating module; the transmission device is horizontally arranged below the furnace body for transmitting the carbon fibers; the invention can not only flexibly adjust the temperature during oxidation of the carbon fibers, but also realize progressive cooling during cooling of the carbon fibers; the temperature control has high precision, fast change and good effect.

Description

Technical Field

[0001] The invention relates to the technical field of carbon fiber preparation, and in particular to a carbon fiber preoxidation furnace based on cooling and a preoxidation method for preparing NFs. Background Art

[0002] As a high-performance material, carbon fiber is widely used in aerospace, automobile manufacturing, sports equipment and other fields. The pre-oxidation stage in its preparation process is particularly critical. The pre-oxidation process is usually carried out at a temperature of 200°C to 300°C. By heating and oxidizing the polyacrylonitrile (PAN)-based fibers, the chemical structure of the fibers changes to form a thermally stable cyclized structure. However, in traditional pre-oxidation furnaces, due to the limited response speed of the temperature control system, the temperature distribution in different areas of the furnace is often uneven, which can easily lead to local overheating or overcooling of the fibers, thus affecting the quality of the final product.

[0003] In order to improve temperature uniformity, the existing technology has proposed a variety of heating and cooling combination solutions; for example, a multi-zone independent temperature control system is used to accurately control the temperature of each heating zone to reduce the temperature gradient; however, these methods still have shortcomings in practical applications: the cooling efficiency of the traditional cooling system is low and the local temperature cannot be adjusted quickly, resulting in unstable physical properties of the fiber during the heating and cooling process; especially when dealing with nitrile-based fibers and nanofibers (NFs), their fine structures are extremely sensitive to temperature changes and are more easily affected. Summary of the invention

[0004] In view of the above problems, a carbon fiber pre-oxidation furnace based on cooling is provided, which proposes a combined system that can not only achieve efficient and uniform heating but also progressive cooling; thereby solving the technical problems that when the existing equipment oxidizes the carbon fiber, the physical properties of the carbon fiber are unstable due to low heating efficiency and poor temperature control effect; and the carbon fiber cannot be progressively cooled during cooling, which causes the carbon fiber structure to be easy to break.

[0005] In order to solve the problems of the prior art, the present invention provides a carbon fiber pre-oxidation furnace based on cooling, comprising a frame, a furnace body arranged on the frame, and an oxidizing device fixedly arranged horizontally in the furnace body, wherein a plurality of groups of the oxidizing devices are arranged equidistantly along the long side direction of the furnace body; the oxidizing device is characterized in that the oxidizing device is composed of a heating module and a cooling module; wherein the heating module is provided with a plurality of heating elements capable of heating the carbon fiber; and the heating element and the cooling module are arranged in series to realize flexible regulation of the heating temperature of the heating element; the cooling module is provided with a regulating medium capable of continuously passing through the heating element and capable of regulating the temperature of the heating element; an air cooling module is vertically arranged below the cooling module to perform air cooling on the heating module; and a transmission device is horizontally arranged below the furnace body. , used to transmit carbon fiber; the cooling module includes a regulating medium storage box and a control element capable of introducing the regulating medium in the regulating medium storage box into the heating element, so as to realize the regulation of the heating element in the heating or cooling state respectively; the regulating medium storage box is provided with four, namely the main storage box, the high temperature storage box, the constant temperature storage box and the low temperature storage box; the high temperature storage box, the constant temperature storage box and the low temperature storage box are all connected with the main storage box through a transmission pipeline; the main storage box is connected with the heating element; multiple groups of transmission pipelines are all controlled by the control element; the cooling module also includes a linear drive capable of controlling the overall longitudinal movement of the oxidation device; it is used to adjust the distance between the heating tube and the carbon fiber and control the heating temperature of the carbon fiber.

[0006] Preferably, the heating element is a heating tube, and a plurality of groups of the heating tubes are equidistantly arranged along the long side of the rack; the plurality of groups of heating tubes are a multi-section parallel pipeline structure to enhance the heat exchange efficiency during the heating and cooling process.

[0007] Preferably, the heating module further comprises a shell and a heating element capable of heating the heating element; the heating element is horizontally fixedly arranged under the cooling module and the heating end is horizontally arranged close to the heating element.

[0008] Preferably, the heating module also includes a temperature control module and a first temperature detector; the temperature control module is connected to the heating element; and is used to adjust the heating intensity of the electromagnetic coil; the first temperature detector is fixedly arranged below the cooling module and the detection end is arranged toward the heating element.

[0009] Preferably, a second temperature detector is also provided in each of the conditioning medium storage boxes.

[0010] Preferably, the air cooling module includes a wind source generator capable of outputting wind source toward both sides and a wind source receiver relatively arranged on both sides of the wind source generator; the wind source generator and the wind source receiver are both horizontally fixed below the cooling module by a second mounting frame.

[0011] A preoxidation method for preparing carbon fiber based on cooling is applied to a carbon fiber preoxidation furnace based on cooling, comprising the following steps:

[0012] S1: First, the carbon fiber to be processed is transported from the feed port to the pre-oxidation furnace by starting the transmission module; the transmission module transports the carbon fiber along a predetermined path to the bottom of the oxidation device located in the furnace body;

[0013] S2: When the carbon fiber reaches the oxidation device position, the heating module is started; the heating tube and the heating element in the heating module work together to quickly raise the temperature of the heating element to 200°C to 300°C, and the carbon fiber begins to be pre-oxidized; during the heating process, the output power of the heating element is controlled to ensure uniform distribution of heat energy, thereby avoiding local overheating of the carbon fiber;

[0014] S3: To ensure uniform temperature distribution during heating, the cooling module can be started at an appropriate time; by adjusting the flow of the medium in the heating tube, the heat energy of the heating element is precisely controlled to further ensure the uniformity of heating of the carbon fiber; the purpose of this step is to maintain the temperature stability in the furnace by balancing the heat input and output, thereby optimizing the cyclization reaction of the carbon fiber;

[0015] S4: After the pre-oxidation treatment is completed, the heating module is stopped and the cooling module is started; the cooling module gradually takes away the residual heat of the heating element by introducing a low-temperature regulating medium into the heating tube, so that the temperature in the furnace is slowly reduced and the cooling medium can flow through each heating tube quickly and evenly through the parallel structure of the heating pipeline, ensuring the uniformity of the cooling process and avoiding thermal stress of the carbon fiber due to sudden cooling;

[0016] S5: When the temperature inside the furnace drops to a safe range, the transmission module starts again to transport the pre-oxidized carbon fiber out of the furnace.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The present invention realizes precise temperature control during the heating process by adopting multiple groups of heating tubes with parallel pipeline structures and a series design of cooling modules and heating elements; and the cooling module can effectively control the temperature distribution of the heating element by adjusting the flow of the medium, so that the carbon fiber is heated more evenly during the pre-oxidation process, avoiding the degradation of fiber quality due to local overheating or overcooling.

[0019] 2. The present invention significantly enhances the heat exchange efficiency during the heating and cooling processes through the multi-section parallel pipeline structure design; the parallel structure of the heating pipes enables the heat energy to be quickly and evenly transferred to the entire heating area, and the cooling medium can also efficiently take away the heat during the cooling stage, thereby achieving efficient switching between heating and cooling.

[0020] 3. In the cooling process after pre-oxidation, the present invention realizes a gradual cooling treatment by gradually introducing a low-temperature regulating medium through controlling the cooling module; effectively preventing the thermal stress of the carbon fiber caused by sudden cooling during the cooling process, and protecting the microstructural integrity of the carbon fiber.

[0021] 4. The present invention realizes how to quickly reduce the temperature of the heating element and its surrounding area through a wind source generator and a wind source receiver arranged on both sides of the wind source generator, and quickly removes heat energy through convection, thereby significantly improving the cooling efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A perspective view of a cooling-based carbon fiber pre-oxidation furnace.

[0023] Figure 2 It is an exploded perspective view of a cooling-based carbon fiber pre-oxidation furnace.

[0024] Figure 3 It is a stereoscopic diagram of a heating module and a cooling module in a carbon fiber pre-oxidation furnace based on cooling.

[0025] Figure 4 It is a three-dimensional diagram of the partial structural decomposition of the heating module and the cooling module in a carbon fiber pre-oxidation furnace based on cooling.

[0026] Figure 5 The figure is a top view of a heating module and a cooling module in a carbon fiber pre-oxidation furnace based on cooling.

[0027] Figure 6 yes Figure 5 A perspective cross-sectional view of the section at AA.

[0028] Figure 7 yes Figure 6 A partial enlarged view of point B.

[0029] Figure 8 It is a three-dimensional structure of the heating module and cooling module in the carbon fiber pre-oxidation furnace based on cooling. Figure 1 .

[0030] Fig. 9 It is a side view of the heating module and cooling module in a carbon fiber pre-oxidation furnace based on cooling.

[0031] Fig.10 It is a three-dimensional structure of the heating module and cooling module in the carbon fiber pre-oxidation furnace based on cooling. Figure 2 .

[0032] The numbers in the figure are:

[0033] 1- rack;

[0034] 2-furnace body;

[0035] 3- Oxidation device;

[0036] 4-heating module; 41-heating element; 42-housing; 43-heating element; 44-first mounting frame; 45-temperature control module; 46-first temperature detector;

[0037] 5-cooling module; 51-adjusting medium storage box; 511-main storage box; 512-high temperature storage box; 513-constant temperature storage box; 514-low temperature storage box; 52-control element; 521-high temperature circulation pump; 522-transmission pipeline; 523-opening and closing element; 53-linear drive; 54-second temperature detector;

[0038] 6-air cooling module; 61-wind source generator; 62-wind source receiver; 63-second mounting frame;

[0039] 7-Transmission module. DETAILED DESCRIPTION

[0040] In order to further understand the features, technical means, specific objectives and functions of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0041] See also Figures 1 to 10 As shown: A carbon fiber pre-oxidation furnace based on cooling, comprising a frame 1, a furnace body 2 arranged on the frame 1, and an oxidation device 3 horizontally fixedly arranged in the furnace body 2, wherein a plurality of groups of the oxidation devices 3 are equidistantly arranged along the long side direction of the furnace body 2; characterized in that the oxidation device 3 is composed of a heating module 4 and a cooling module 5; wherein the heating module 4 is provided with a plurality of heating elements 41 capable of heating the carbon fiber; and the heating element 41 is arranged in series with the cooling module 5 to realize flexible regulation of the heating temperature of the heating element 41; the cooling module 5 is provided with a regulating medium capable of continuously passing through the heating element 41 and capable of regulating the temperature of the heating element 41; an air cooling module 6 is vertically arranged below the cooling module 5 to perform air cooling on the heating module 4; a transmission device is horizontally arranged below the furnace body 2 to transmit the carbon fiber.

[0042] When the carbon fiber is oxidized, the transmission module 7 is first driven by connecting to an external power supply, and the transmission module 7 transports the carbon fiber to be oxidized to the position of the oxidation device 3; when the carbon fiber moves to the working area of ​​the oxidation device 3, the heating module 4 is started, and the temperature is quickly raised to a predetermined range of 200°C to 300°C, and the carbon fiber is oxidized; in order to ensure that the temperature distribution of the heating element 41 is uniform during the heating process, thereby ensuring the uniformity and quality of the heat treatment of the carbon fiber during the entire oxidation process, the cooling module 5 can be started at this time to cause the regulating medium to pass through the heating element 41; by regulating the flow of the medium, the heat energy distribution of the heating element 41 can be accurately controlled, so that the temperature of each part of the heating element 41 tends to be uniform; when the oxidation treatment is completed and the carbon fiber needs to be cooled, the cooling module 5 is started again, and the low-temperature regulating medium is introduced into the interior of the heating module 4, and the residual heat of the heating element 41 is gradually taken away to achieve temperature control and progressive cooling of the heating area; this control strategy not only ensures that the carbon fiber can quickly achieve a uniform high-temperature treatment effect during the oxidation process, but also realizes gradual and stable low-temperature cooling during the cooling process, thereby protecting the structural integrity and performance stability of the carbon fiber to the greatest extent.

[0043] See also Figure 4 As shown: the heating element 41 is a heating tube, and a plurality of groups of the heating tubes are equidistantly arranged along the long side direction of the rack 1; the plurality of groups of heating tubes are a multi-section parallel pipeline structure, which is used to enhance the heat exchange efficiency during the heating and cooling process.

[0044] The heating element 41 is in the form of a heating tube, which is arranged equidistantly along the long side of the frame 1 to form an independent heating zone; and since each group of heating tubes is connected by a multi-section parallel pipe structure, during the heating process, the parallel structure enables the heat energy to be more evenly distributed in the entire heating area, thereby reducing the temperature gradient caused by local overheating or overcooling, and ensuring the temperature consistency of the carbon fiber during the pre-oxidation treatment; in addition, during the cooling stage, the parallel structure allows the cooling medium to flow through the heating tube more efficiently, quickly taking away the heat, thereby achieving rapid cooling of the heating tube;

[0045] The two ends of the plurality of groups of heating tubes are respectively connected to the outlet end and the inlet end of the cooling module 5, so as to realize the inlet and outlet of the regulating medium during the heating or cooling process.

[0046] See also Figure 3 and Figure 4 As shown: the heating module 4 also includes a shell 42 and a heating element 43 capable of heating the heating element 41; the heating element 43 is horizontally fixedly arranged under the cooling module 5 and the heating end is horizontally arranged close to the heating element 41.

[0047] The heating module 4 is horizontally fixed in the furnace body 2 through the shell 42;

[0048] The heating element 43 is preferably an electromagnetic coil, and the electromagnetic coil is fixedly arranged below the cooling module 5 in a horizontal state through a first mounting frame 44;

[0049] Since the heating element 41 is a heating tube and does not have an autonomous heating function, a heating element 43 is arranged horizontally close to the heating element 41; it can directly and effectively transfer heat to the heating element 41, so as to provide a stable and uniform heat source; it can provide heat energy at the position closest to the heating element 41, reducing the loss of heat energy in the conduction process, thereby improving the heating efficiency; at the same time, due to the close arrangement of the heating element 43 and the heating element 41, the thermal response speed of the entire heating system is optimized, and the required operating temperature can be reached more quickly; this arrangement not only improves the overall working efficiency of the heating module 4, but also ensures that the carbon fiber can obtain uniform and stable heat treatment during the pre-oxidation process.

[0050] See also Fig.10 As shown: the heating module 4 also includes a temperature control module 45 and a first temperature detector 46; the temperature control module 45 is connected to the heating element 43; and is used to adjust the heating intensity of the electromagnetic coil; the first temperature detector 46 is fixedly arranged below the cooling module 5 and the detection end is arranged toward the heating element 41.

[0051] Through the temperature control module 45, the working state of the electromagnetic coil can be accurately adjusted according to actual needs, so as to flexibly control the temperature of the heating element 41; in order to achieve more precise temperature control, the heating module 4 is also provided with a first temperature detector 46, which is fixed under the cooling module 5 and the detection end is arranged toward the heating element 41, so as to realize real-time monitoring of the temperature of the heating element 41 and feed back the data to the temperature control module 45 to ensure the stability and uniformity of the temperature of the heating element 41; the temperature control module 45 and the first temperature detector 46 are both existing technologies and will not be elaborated here.

[0052] See also Figure 3 and Figure 4 As shown: the cooling module 5 includes a regulating medium storage box 51 and a control element 52 capable of introducing the regulating medium in the regulating medium storage box 51 into the heating element 41, so as to achieve regulation of the heating element 41 in the heating or cooling state.

[0053] The regulating medium is preferably silicone oil, but is not limited to silicone oil and may also be synthetic heat transfer oil; for the purpose of achieving high temperature conduction;

[0054] The control element 52 is a control center, which is used to realize the work of adjusting the medium of different temperatures toward the heating element 41 through the cooperation of the high-temperature circulation pump 521, the transmission pipeline 522 and the opening and closing element 523;

[0055] The regulating medium storage box 51 is used to store regulating media of different temperatures; the control element 52 can introduce these regulating media into the heating element 41 in sequence or simultaneously as needed; in the heating state, the control element 52 can adjust the medium introduced at an appropriate temperature to help maintain the temperature stability of the heating element 41 and to heat the heating element 41 synchronously through the regulating medium during the heating process so that it is heated evenly; and when in the cooling state, the control element 52 introduces a low-temperature regulating medium to effectively reduce the temperature of the heating element 41, thereby realizing flexible regulation of the heating process and the cooling process; ensuring that the carbon fiber obtains more precise temperature control during the pre-oxidation process, thereby improving the uniformity and efficiency of the pre-oxidation effect.

[0056] See also Figure 4 As shown: the regulating medium storage box 51 is provided with four, namely the main storage box 511, the high temperature storage box 512, the constant temperature storage box 513 and the low temperature storage box 514; the high temperature storage box 512, the constant temperature storage box 513 and the low temperature storage box 514 are all connected with the main storage box 511 through the transmission pipeline 522; the main storage box 511 is connected with the heating element 41; the multiple groups of transmission pipelines 522 are all controlled by the control element 52 to open and close.

[0057] By setting up multiple groups of storage boxes, the present invention can store regulating media of different temperatures, and by cooperating with the control element 52, the medium temperature can be flexibly adjusted during the heating and cooling process, ensuring the long-term constant temperature of the heating element 41 and the progressive cooling effect during cooling; when heating the carbon fiber, the control element 52 will circulate the regulating medium in the main storage box 511 to the heating element 41 for conduction, so that the temperature of the heating element 41 rises evenly while avoiding the problem of local temperature unevenness; similarly, when it is necessary to cool the heating element 41, the high-temperature regulating medium in the main storage box 511 is first exported, and then transmitted through the transmission pipeline 522 gradually introduces the low-temperature regulating medium mixed with the high-temperature regulating medium in the low-temperature storage box 514 into the main storage box 511, and gradually reduces the mixing amount of the high-temperature regulating medium during the subsequent introduction process; this process can avoid the problem of rapid cooling caused by excessive temperature difference, and control the steady decrease of the cooling rate; until the heating element 41 is completely cooled; through the combination of multiple groups of storage boxes and control elements 52, precise control of the temperature of the heating element 41 is achieved, ensuring the temperature uniformity and stability during the heating and cooling process, avoiding thermal stress caused by rapid cooling, thereby improving the pre-oxidation quality of the carbon fiber and the performance of the final product.

[0058] See also Figure 8 As shown: a second temperature detector 54 is also provided in each of the conditioning medium storage boxes 51 .

[0059] By respectively setting the second temperature detectors 54 in the regulating medium storage boxes 51, it is possible to monitor the temperature of the regulating medium in the storage boxes in real time. This not only ensures that the temperature of the regulating medium in different storage boxes is accurately controlled and adjusted before transmission, thereby avoiding unstable heating or cooling effects caused by temperature deviations, but also the data of the second temperature detectors 54 can be fed back to the temperature control system, making the temperature regulation in the entire heating and cooling process more accurate, further improving the stability and uniformity of temperature control during carbon fiber pre-oxidation.

[0060] See also Figure 8 As shown, the cooling module 5 also includes a linear driver 53 capable of controlling the overall longitudinal movement of the oxidation device 3, so as to adjust the distance between the heating tube and the carbon fiber and control the heating temperature of the carbon fiber.

[0061] The linear drive 53 is provided in four groups, and the four groups of linear drives 53 are arranged on the upper surface of the housing 42 in a rectangular array state, and the output shaft passes through the housing 42 and is fixedly connected to the oxidation device 3;

[0062] By setting up four groups of linear drives 53, flexible control of the heating temperature of the carbon fiber can be achieved: when the heating intensity needs to be increased, the heating tube can be brought closer to the carbon fiber; conversely, when the heating intensity needs to be reduced or uniform heating is required, the distance between the two can be appropriately increased; thereby not only the heating temperature of the carbon fiber can be accurately controlled, but also the uniformity of the oxidation process can be improved.

[0063] See also Fig.10 As shown: the air cooling module 6 includes a wind source generator 61 capable of outputting wind source toward both sides respectively, and a wind source receiver 62 relatively arranged on both sides of the wind source generator 61; the wind source generator 61 and the wind source receiver 62 are both horizontally fixedly arranged below the cooling module 5 through a second mounting frame 63.

[0064] The wind source generator 61 is horizontally arranged in the middle of the multiple groups of heating elements 41 through the second mounting frame 63, and the two groups of wind source receivers 62 are respectively located on both sides of the multiple groups of heating elements 41; when the heating elements 41 need to be further cooled, the wind source generator 61 is started to output wind sources to both sides, and the heat energy on the heating elements 41 is blown to the wind source receivers 62 arranged on both sides; at this time, the wind source receivers 62 are in a continuous air suction state, which can effectively absorb and remove the hot air and heat energy blown by the wind source generator 61; thereby quickly reducing the temperature of the heating elements 41 and the surrounding areas, and quickly removing heat energy by convection, thereby further improving the cooling efficiency; compared with the traditional cooling method, this design significantly improves the cooling speed and the accuracy of temperature control, which helps to maintain the temperature stability during the pre-oxidation process of carbon fiber and improve product quality.

[0065] A preoxidation method for preparing carbon fiber based on cooling, and a carbon fiber preoxidation furnace based on cooling, comprising the following steps:

[0066] S1: First, the carbon fiber to be processed is transported from the feed port to the pre-oxidation furnace by starting the transmission module 7; the transmission module 7 transports the carbon fiber along a predetermined path to below the oxidation device 3 located in the furnace body 2;

[0067] S2: When the carbon fiber reaches the position of the oxidation device 3, the heating module 4 is started; the heating tube and the heating element 43 in the heating module 4 work together to quickly raise the temperature of the heating element 41 to 200°C to 300°C, and the carbon fiber begins to be pre-oxidized; during the heating process, the output power of the heating element 43 is controlled to ensure uniform distribution of heat energy, thereby avoiding local overheating of the carbon fiber;

[0068] S3: To ensure uniform temperature distribution during the heating process, the cooling module 5 can be started at an appropriate time; by adjusting the flow of the medium in the heating tube, the heat energy of the heating element 41 is precisely regulated to further ensure the uniformity of heating of the carbon fiber; the purpose of this step is to maintain the temperature stability in the furnace by balancing the heat input and output, thereby optimizing the cyclization reaction of the carbon fiber;

[0069] S4: When the pre-oxidation treatment is completed, the heating module 4 is stopped and the cooling module 5 is started; the cooling module 5 gradually takes away the residual heat of the heating element 41 by introducing a low-temperature regulating medium into the heating tube, so that the temperature in the furnace is slowly reduced and the cooling medium can flow through each heating tube quickly and evenly through the parallel heating pipeline, thereby ensuring the uniformity of the cooling process and avoiding thermal stress of the carbon fiber due to sudden cooling;

[0070] S5: When the temperature in the furnace drops to a safe range, the transmission module 7 is started again to transport the pre-oxidized carbon fibers out of the furnace body 2.

[0071] The present invention can not only flexibly regulate the temperature during oxidation of carbon fibers, but also realize progressive temperature reduction during cooling of the carbon fibers; the temperature control has high precision, fast change and good effect.

[0072] The above embodiments only express one or several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A carbon fiber preoxidation furnace based on cooling, comprising a frame, a furnace body arranged on the frame, and an oxidation device horizontally fixedly arranged in the furnace body, wherein a plurality of groups of the oxidation devices are arranged equidistantly along the long side direction of the furnace body; characterized in that: The oxidation device is composed of a heating module and a cooling module; the heating module is provided with a plurality of heating elements capable of heating carbon fibers; and the heating elements are arranged in series with the cooling module to realize flexible regulation of the heating temperature of the heating elements; the cooling module is provided with a regulating medium capable of continuously passing through the heating elements and capable of regulating the temperature of the heating elements; the air cooling module is vertically arranged below the cooling module to perform air cooling on the heating module; the transmission device is horizontally arranged below the furnace body to transmit the carbon fibers; the cooling module includes a regulating medium storage box and a regulating medium storage box capable of transferring the regulating medium in the regulating medium storage box to the heating module; The control element introduced into the heating element is used to adjust the heating element in the heating or cooling state respectively; there are four regulating medium storage boxes, namely the main storage box, the high-temperature storage box, the constant temperature storage box and the low-temperature storage box; the high-temperature storage box, the constant temperature storage box and the low-temperature storage box are all connected to the main storage box through a transmission pipeline; the main storage box is connected to the heating element; multiple groups of transmission pipelines are all controlled by the control element to open and close; the cooling module also includes a linear drive that can control the overall longitudinal movement of the oxidation device; it is used to adjust the distance between the heating tube and the carbon fiber and control the heating temperature of the carbon fiber.

2. A cooling-based carbon fiber preoxidation furnace according to claim 1, characterized in that: The heating elements are heating tubes, and a plurality of groups of the heating tubes are equidistantly arranged along the long side of the rack; the plurality of groups of heating tubes are multi-section parallel pipeline structures to enhance the heat exchange efficiency during heating and cooling.

3. A cooling-based carbon fiber preoxidation furnace according to claim 1, characterized in that: The heating module also includes a shell and a heating element capable of heating the heating element; the heating element is horizontally fixedly arranged under the cooling module and the heating end is horizontally arranged close to the heating element.

4. A cooling-based carbon fiber preoxidation furnace according to claim 3, characterized in that: The heating module also includes a temperature control module and a first temperature detector; the temperature control module is connected to the heating element and is used to adjust the heating intensity of the electromagnetic coil; the first temperature detector is fixedly arranged below the cooling module and the detection end is arranged toward the heating element.

5. A cooling-based carbon fiber preoxidation furnace according to claim 1, characterized in that: A second temperature detector is also provided in each of the conditioning medium storage boxes.

6. A cooling-based carbon fiber preoxidation furnace according to claim 1, characterized in that: The air cooling module includes a wind source generator capable of outputting wind source toward both sides and a wind source receiver relatively arranged on both sides of the wind source generator; the wind source generator and the wind source receiver are both horizontally fixed below the cooling module through a second mounting frame.

7. A preoxidation method for preparing carbon fiber based on cooling, applied to a carbon fiber preoxidation furnace based on cooling as described in any one of claims 1 to 6, comprising the following steps: S1: First, the carbon fiber to be processed is transported from the feed port to the pre-oxidation furnace by starting the transmission module; the transmission module transports the carbon fiber along a predetermined path to the bottom of the oxidation device located in the furnace body; S2: When the carbon fiber reaches the oxidation device position, the heating module is started; the heating tube and the heating element in the heating module work together to quickly raise the temperature of the heating element to 200°C to 300°C, and the carbon fiber begins to be pre-oxidized; during the heating process, the output power of the heating element is controlled to ensure uniform distribution of heat energy, thereby avoiding local overheating of the carbon fiber; S3: To ensure uniform temperature distribution during heating, the cooling module is started at the appropriate time; by adjusting the flow of the medium in the heating tube, the heat energy of the heating element is precisely controlled to further ensure the uniformity of heating of the carbon fiber; the purpose of this step is to maintain the temperature stability in the furnace by balancing the heat input and output, thereby optimizing the cyclization reaction of the carbon fiber; S4: When the pre-oxidation treatment is completed, the heating module is stopped and the cooling module is started; The cooling module gradually takes away the residual heat of the heating element by introducing low-temperature regulating medium into the heating tube, causing the temperature in the furnace to slowly decrease. Through the parallel structure of the heating pipeline, the cooling medium can flow through each heating tube quickly and evenly, ensuring the uniformity of the cooling process and avoiding thermal stress of the carbon fiber due to sudden cooling; S5: When the temperature inside the furnace drops to a safe range, the transmission module starts again to transport the pre-oxidized carbon fiber out of the furnace.

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