A device for producing carbon fiber felt

Abstract

A device for producing carbon fiber felt, which consists of two furnace bodies, a foaming furnace and a carbonization furnace. The foaming furnace and the carbonization furnace are connected through a sealed first atmosphere buffer box to prevent external air from entering. The foaming furnace is used to prepare a high-porosity carbon fiber felt precursor through a foaming process. The foaming furnace is mainly composed of a screw conveying mechanism, a heating device and a gas introduction device; the carbonization furnace is used to heat-treat the carbon fiber felt precursor to obtain a final product. The carbonization furnace is mainly composed of a heating device and a traction device. This device fully ensures the uniformity of the distribution of carbon fibers in the carbon felt and reduces the density of the carbon fiber felt through the foaming process, thereby further improving the thermal insulation performance of the product. The production can achieve fully continuous production and the production raw materials can use waste materials, thereby further reducing the production cost.

Description

Technical Field

[0001] The invention relates to the technical field of carbon felt production, and in particular to a device for producing carbon fiber felt. Background Art

[0002] Carbon fiber felt is a blank material for preparing carbon / carbon composite structural materials and carbon / carbon composite thermal insulation materials. At present, there are two main methods for preparing carbon felt cylinders for thermal insulation in my country: 1. Using soft carbon felt wrapped on a thermal insulation cylinder made of graphite material; 2. Using a graphite soft felt body wrapped around a cylindrical mold to make a blank, and then pressurizing and curing after uniformly infiltrating a curing agent, and then undergoing carbonization and graphitization to obtain a cured carbon felt thermal insulation cylinder (such as patent number 200610136811X). The thermal insulation effect of the carbon felt thermal insulation cylinder prepared by the former method is average, and it occupies a large space and has a short service life; while each thermal insulation cylinder of the cured carbon felt prepared by the latter method must be completed on the mold. When the number of molds is limited, the production time will be extended, the production cost is high, and the hollow cylinder is easily damaged during storage and transportation. Moreover, this thermal insulation cylinder is a whole. If it is damaged at one place, it needs to be replaced as a whole, resulting in an increase in the cost of use.

[0003] CN100567217C proposes a method for preparing high-purity solidified carbon felt for silicon crystal growth furnace, wherein the product is made into graphite felt body by high-temperature pretreatment; a blank is made by using the graphite felt body; the blank uniformly infiltrated with curing agent is solidified and shaped; the blank is carbonized; chemical vapor pre-deposition is performed on the blank; mechanical cutting is performed on the surface of the part that needs cutting; and the blank is treated at high temperature. The solidified carbon felt prepared by the method has low thermal conductivity, good energy-saving and heat-insulating effect, light weight and high strength, stable quality, reliable use, and the metal impurity content can be controlled within 300 ppm or even 100 ppm, but there are still disadvantages of complex product preparation process and poor product heat-insulating effect.

[0004] CN202430447U proposes a device for preparing pre-oxidized thick felt by double-sided oblique needle punching, and the lifting mechanism drives the lifting plate to connect the lifting plate. The double-sided needle punching device of the utility model saves process flow, has strong uniformity, is easy to operate, can be produced continuously, has high production efficiency, and is suitable for batch production. However, the preparation process of this equipment is still a traditional carbon felt production process, and there are disadvantages in the production process such as complex process and poor product insulation effect.

[0005] CN102505340A proposes a method for preparing a preoxidized thick felt, and provides a method for preparing a preoxidized thick felt. The method can produce a preoxidized integral felt with good uniformity, and after subsequent carbonization treatment and high temperature treatment, a carbon fiber thermal insulation felt with excellent thermal insulation performance and long service life can be obtained. The equipment structure of the invention is simple, the operation is simple, and continuous production can be achieved with high production efficiency, which is suitable for batch production. However, this method still has the disadvantages of poor product performance and limited production continuity. Summary of the invention

[0006] The present invention solves the deficiencies of the above-mentioned technology and provides a device for producing carbon fiber carbon felt. The equipment for producing carbon fiber carbon felt adopts a combined design of a foaming furnace and a carbonization furnace to achieve fully continuous production with high output. There is no need to stop heating during the production process and the stability is strong. The foaming and carbonization steps are completely separated and do not affect each other. The material loading and unloading is convenient, and the continuous operation of the equipment is realized, the production efficiency is improved, the product performance is better, and the industry needs can be better met.

[0007] The technical solution adopted by the present invention to solve its technical problems is as follows: a device for producing carbon fiber carbon felt, comprising at least one production line consisting of a foaming furnace 1, a carbonization furnace 2 and a first atmosphere buffer box 3, the outlet of the foaming furnace 1 is connected to the inlet of the carbonization furnace 2 through the first atmosphere buffer box 3, the outlet of the carbonization furnace 2 is connected to the second atmosphere buffer box 11, the foaming furnace 1 comprises a feeding conveying mechanism 41, a heating device 5 and a foaming medium introduction device 6, the outside of the feeding conveying mechanism 41 is wrapped with a heating device, and the foaming medium introduction device 6 is connected to the outlet end of the conveying cavity of the feeding conveying mechanism 41; the carbonization furnace 2 comprises a partition control heating device 7 and a first conveying device 8 arranged in the furnace body of the partition control heating device 7, the first atmosphere buffer box 3 is provided with a second conveying device 10 and a first inert atmosphere introduction device 9 for introducing inert gas into the first atmosphere buffer box 3; the second atmosphere buffer box 11 is provided with a second inert atmosphere introduction device 18 for introducing inert gas into the second atmosphere buffer box 11.

[0008] In this embodiment, the inlet and outlet of the first atmosphere buffer box 3 are connected to the foaming furnace 1 and the carbonization furnace 2 through the first valve 12 and the second valve 13 respectively, and the outlet of the carbonization furnace 2 is connected to the inlet of the second atmosphere buffer box through the third valve 14.

[0009] In this embodiment, a plurality of insulation materials are arranged inside the furnace body of the partitioned controlled heating device 7, within the conveying track range of the first conveying equipment 8, from the inlet to the outlet to divide the furnace body into a plurality of heat fields in the horizontal direction, and the middle part of the furnace body is the central temperature zone 19.

[0010] In this embodiment, three heat fields are arranged in the furnace body of the zone-controlled heating device 7 .

[0011] In this embodiment, five heat fields are arranged in the furnace body of the zone-controlled heating device 7 .

[0012] In this embodiment, the feeding and conveying mechanism 41 in the foaming furnace 1 is a screw feeding mechanism, an injection feeding mechanism, or a push plate feeding and conveying mechanism.

[0013] In this embodiment, temperature detectors for real-time temperature monitoring are installed in the foaming furnace 1 and the carbonization furnace 2. The temperature detectors are electrically connected to the controller, and the heating device 5 and the zone-controlled heating device 7 are electrically connected to the controller.

[0014] In this embodiment, the foaming medium introduction device 6 includes a medium transmission pipeline and a foaming medium in the pipeline, and the medium transmission pipeline includes a pressure detector for real-time monitoring of the pressure in the heating reaction tank.

[0015] In this embodiment, the first and second conveying devices are push plate conveying mechanisms, roller conveying mechanisms, or rope conveying mechanisms.

[0016] In this embodiment, the zone-controlled heating device 7 includes a plurality of heaters, and each zone where the heater is located is provided with a temperature sensor for separate program temperature control.

[0017] The beneficial effects of the present invention are as follows:

[0018] (1) Through the foaming furnace, the carbon fibers are evenly dispersed in the blank during the process of being transported from the inlet to the outlet of the foaming furnace. Later, the foaming medium is introduced through the foaming medium introduction device to foam the material, thereby maintaining the uniform distribution of the carbon fibers and ensuring the mechanical properties of the material.

[0019] (2) The overall density of carbon fiber felt is further reduced through the foaming process to enhance the thermal insulation performance.

[0020] (3) The foaming furnace and the carbonization furnace are connected through the first atmosphere buffer box, and the carbonization furnace does not need to be cooled, thereby realizing fully continuous production.

[0021] In summary, the present invention consists of two furnace bodies, a foaming furnace and a carbonization furnace. The foaming furnace is connected to the carbonization furnace through a sealed first atmosphere buffer box to prevent external air from entering. The foaming furnace is used to prepare a high-porosity carbon fiber carbon felt precursor through a foaming process, and the foaming furnace is mainly composed of a screw conveying mechanism, a heating device and a gas introduction device; the carbonization furnace is used to heat-treat the carbon fiber carbon felt precursor to obtain a final product, and the carbonization furnace is mainly composed of a heating device and a traction device. This device solves the problems of poor product performance and serious pollution in previous carbon fiber carbon felt equipment and preparation methods. The foaming process fully ensures the uniformity of the distribution of carbon fiber in the carbon felt and reduces the density of the carbon fiber carbon felt, thereby further improving the thermal insulation performance of the product, and the production can achieve fully continuous production and waste materials can be used as production raw materials, thereby further reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0023] Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0024] Figure 3 This is a schematic diagram of the structure of Embodiment 3 of the present invention;

[0025] In the figure, 1, foaming furnace; 2, carbonization furnace; 3, first atmosphere buffer box; 4, feed hopper; 5, heating device; 6, foaming medium introduction device; 7, zone control heating device; 8, first conveying equipment; 9, inert atmosphere introduction device; 10, second conveying equipment; 11, second atmosphere buffer box; 12, first valve; 13, second valve; 14, third valve; 15, first flange; 16, second flange; 17, third flange; 18, second inert atmosphere introduction device; 19, central temperature zone. DETAILED DESCRIPTION

[0026] The present invention is further described below in conjunction with embodiments and drawings.

[0027] The following is a preferred implementation of the embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the embodiment of the present invention. These improvements and modifications are also within the scope of protection requested by this patent application.

[0028] In each embodiment, the raw materials used are common commercially available products. Example 1

[0029] like Figure 1As shown, the equipment of this embodiment is composed of a foaming furnace 1, a carbonization furnace 2, a first atmosphere buffer box 3, and a second atmosphere buffer box 11. The foaming furnace 1, the carbonization furnace 2, the first atmosphere buffer box 3, and the second atmosphere buffer box 11 are connected by a first flange 15, a second flange 16, and a third flange 17, respectively, and the flange connection is sealed with a sealing ring; and the inlet and outlet of the first atmosphere buffer box 3 are connected to the foaming furnace 1 and the carbonization furnace 2 through a first valve 12 and a second valve 13, respectively, and the outlet of the carbonization furnace 2 is connected to the inlet of the second atmosphere buffer box through a third valve 14. The first valve 12, the second valve 13, and the third valve 14 are used to connect and close the flow of materials and gases between various spaces.

[0030] The function of the first and second atmosphere buffer boxes is to maintain an inert atmosphere in the carbonization furnace 2 to prevent the carbon fiber felt from being oxidized at high temperatures;

[0031] The foaming furnace 1 is used to prepare a high-porosity carbon fiber felt precursor through a foaming process. The foaming furnace 1 is mainly composed of a feed hopper 4, a feed conveying mechanism, a heating device 5 and a foaming medium introduction device 6. The raw material resin and carbon fiber enter through the feed hopper 4 and are conveyed through the feed conveying mechanism. In this example, the feed conveying mechanism 41 is a screw conveying mechanism. The raw material is converted into a liquid at the temperature provided by the external heating device 5 of the foaming furnace 1, and a high-pressure fluid is formed under the action of the introduced foaming medium. When the space is released, the volume of the raw material increases instantly to form a carbon fiber felt precursor.

[0032] The carbonization furnace 2 is used to heat-treat the carbon fiber felt precursor to obtain the carbon fiber felt. The carbonization furnace 2 is mainly composed of a partition-controlled heating device 7 and a first conveying device 8. The partition-controlled heating device 7 causes the carbonization furnace to form a high temperature, and is gradually carbonized under the transmission of the first conveying device 8, thereby obtaining a carbon fiber felt product; the atmosphere buffer box is used to ensure that the atmosphere in the carbonization furnace is an inert atmosphere. The first atmosphere buffer box 3 is mainly composed of a first inert atmosphere introduction device 9 and a second conveying device 10; the second atmosphere buffer box 11 is mainly structured as a second inert atmosphere introduction device 18.

[0033] During the operation of this equipment, the carbon fiber can be evenly dispersed in the blank when the raw materials are mixed. The uniformity of the carbon fiber can be continued through the foaming process in the later stage, thereby ensuring the mechanical properties of the material; the foaming process can further reduce the overall density of the carbon fiber felt and enhance the thermal insulation performance; the foaming furnace and the carbonization furnace can be connected, and the heating furnace does not need to be cooled to achieve fully continuous production; the carbon fiber in the raw material of the product can be machined scrap carbon fiber, which is waste in the preparation process of carbon / carbon composite materials, so low-cost preparation can be achieved.

[0034] In this embodiment, the temperature of the central temperature zone of the foaming furnace 1 is 400℃~800℃, and most preferably 600℃~700℃; the foaming medium introduction device 6 includes a medium transmission pipeline and a foaming medium in the pipeline, and the medium transmission pipeline includes a pressure detector for real-time monitoring of the pressure in the heating reaction tank; the foaming medium is anisole; the first conveying equipment 8 adopts a roller conveying device.

[0035] The method for preparing carbon fiber carbon felt using the manufacturing equipment proposed in this embodiment is:

[0036] Step 1, close the first valve 12, the second valve 13, and the third valve 14;

[0037] Step 2: Turn on the heating device 5 and the zone-controlled heating device 7, so that the working temperature of the foaming furnace reaches 150°C to 200°C; the temperature of the central temperature zone 19 of the carbonization furnace reaches 600°C to 700°C, and the temperature of the secondary central temperature zone reaches 400°C to 600°C;

[0038] Step 3, add the raw materials into the feed hopper 4, open the foaming medium introduction device 6, introduce the foaming medium (in this embodiment, the foaming medium is a combination of one or more of water, air, carbon dioxide, freon, anisole, and can be used alone) and adjust the medium pressure so that the medium pressure is between 0.8 MP and 1.2 MP;

[0039] Step 4, opening the first valve 12, allowing the raw materials to enter the first atmosphere buffer box 3 for foaming;

[0040] Step 5: close the first valve 12, evacuate the first atmosphere buffer box 3, and then introduce an inert gas (the inert gas is one or more combinations of argon, nitrogen, and helium) to allow the raw materials to be fully foamed and formed in the first atmosphere buffer box 3 to obtain a carbon fiber carbon felt precursor. In this embodiment, the density of the carbon fiber carbon felt precursor is set to 0.02 g / cm 3 ~0.03 g / cm 3 ;

[0041] Step 6, open the second valve 13, start the second conveying device 10 and the first conveying device 8, and deliver the carbon fiber carbon felt precursor from the first atmosphere buffer box 3 into the carbonization furnace 2, and then close the second valve 13 until the carbonization process is completed;

[0042] Step seven, open the third valve 14, send the finished carbon fiber felt into the second atmosphere buffer box, close the third valve 14, open the flange between the carbonization furnace and the second atmosphere buffer box, take out the carbon fiber felt, close the flange between the carbonization furnace and the second atmosphere buffer box to start the next round of reaction. Example 2

[0043] like Figure 2 As shown, the difference between this embodiment and embodiment 1 is that the carbonization furnace 2 in the carbon fiber carbon felt preparation furnace is divided into 5 heat fields by 4 pieces of insulation materials; under the premise of ensuring good sealing, more levels of temperature control can be achieved to further improve the quality of the prepared products. Example 3

[0044] like Figure 3 As shown, the difference between this embodiment and Embodiment 1 is that this equipment includes two production lines consisting of a foaming furnace, a first atmosphere buffer box and a carbonization furnace, and these two production lines are respectively connected to the same second atmosphere buffer box. Under the premise of ensuring good sealing, the production capacity of the prepared products is further improved. Of course, within a reasonable range, more groups of production lines can also be connected in the same way to further improve the production capacity of the prepared products.

[0045] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A device for producing carbon fiber felt, characterized in that: The invention comprises at least one production line consisting of a foaming furnace (1), a carbonization furnace (2) and a first atmosphere buffer box (3), wherein the outlet of the foaming furnace (1) is connected to the inlet of the carbonization furnace (2) via the first atmosphere buffer box (3), and the outlet of the carbonization furnace (2) is connected to the second atmosphere buffer box (11). The foaming furnace (1) comprises a feed conveying mechanism (41), a heating device (5) and a foaming medium introduction device (6), wherein the feed conveying mechanism (41) is externally wrapped with the heating device, and the foaming medium introduction device (6) is connected to the feed conveying mechanism (41). The conveying mechanism (41) is connected to the outlet end of the conveying cavity; the carbonization furnace (2) comprises a zone-controlled heating device (7) and a first conveying device (8) arranged in the furnace body of the zone-controlled heating device (7); the first atmosphere buffer box (3) is provided with a second conveying device (10) and a first inert atmosphere introduction device (9) for introducing inert gas into the first atmosphere buffer box (3); the second atmosphere buffer box (11) is provided with a second inert atmosphere introduction device (18) for introducing inert gas into the second atmosphere buffer box (11); The inlet and outlet of the first atmosphere buffer box (3) are respectively connected to the foaming furnace (1) and the carbonization furnace (2) through a first valve (12) and a second valve (13); the outlet of the carbonization furnace (2) is connected to the inlet of the second atmosphere buffer box through a third valve (14); A plurality of heat-insulating materials are arranged inside the furnace body of the zone-controlled heating device (7) and within the conveying track range of the first conveying device (8), from the inlet to the outlet, so as to divide the furnace body into a plurality of heat fields in the horizontal direction, and the middle of the furnace body is the central temperature zone (19).

2. The device for producing carbon fiber felt according to claim 1, characterized in that: Three heat fields are arranged in the furnace body of the zone-controlled heating device (7).

3. The equipment for producing carbon fiber felt according to claim 1, characterized in that: Five heat fields are arranged in the furnace body of the zone-controlled heating device (7).

4. The equipment for producing carbon fiber felt according to claim 1, characterized in that: The feeding and conveying mechanism (41) in the foaming furnace (1) is a screw feeding mechanism, an injection feeding mechanism, or a push plate feeding and conveying mechanism.

5. The device for producing carbon fiber felt according to claim 1, characterized in that: The foaming furnace (1) and the carbonization furnace (2) are both equipped with temperature detectors for real-time temperature monitoring. The temperature detectors are electrically connected to a controller, and the heating device (5) and the zone-controlled heating device (7) are electrically connected to the controller.

6. The equipment for producing carbon fiber felt according to claim 1, characterized in that: The foaming medium introduction device (6) comprises a medium transmission pipeline and a foaming medium in the pipeline, and the medium transmission pipeline comprises a pressure detector for real-time monitoring of the pressure inside the heating reaction tank.

7. The equipment for producing carbon fiber felt according to claim 1, characterized in that: The first conveying device (8) and the second conveying device (10) are push plate conveying mechanisms, roller conveying mechanisms or rope conveying mechanisms.

8. The device for producing carbon fiber felt according to claim 1, characterized in that: The zone-controlled heating device (7) comprises a plurality of heaters, and each zone where the heater is located is provided with a temperature sensor for performing independent program temperature control.

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