Carbon fiber waste heat recovery device

Abstract

The utility model discloses a carbon fiber waste heat recovery device which comprises a direct combustion type incinerator T0, a waste heat boiler and an oxidation furnace, the direct combustion type incinerator T0 is communicated with the waste heat boiler through a fresh air heat exchange device, the fresh air heat exchange device is further communicated with the oxidation furnace, a cavity used for heat exchange is formed in the fresh air heat exchange device, and the oxidation furnace is communicated with the waste heat boiler. Fresh air and high-temperature flue gas flow in the cavity in a cross mode, the high-temperature flue gas is introduced into the fresh air heat exchange device from the direct-fired incinerator T0 and then flows into the waste heat boiler, and the fresh air is communicated with the oxidizing furnace through the fresh air heat exchange device. The fresh air heat exchange device is connected between the incinerator and the waste heat boiler, heat is recycled, then the fresh air heat exchange device is communicated with the oxidation furnace, fresh air obtained after heat exchange is conveyed to the oxidation furnace, the electric energy consumption of the oxidation furnace for the oxidation environment is reduced, and the service life is prolonged.

Description

Technical Field

[0001] The utility model belongs to the field of carbon fiber production, and specifically relates to a carbon fiber waste heat recovery device. Background Art

[0002] Carbon fiber is a special fiber composed of carbon elements, with characteristics such as high temperature resistance, friction resistance, electrical conductivity, thermal conductivity, and corrosion resistance. Its shape is fibrous, soft, and can be processed into various fabrics. Due to the preferential orientation of its graphite microcrystal structure along the fiber axis, it has high strength and modulus along the fiber axis direction. The density of carbon fiber is small, so its specific strength and specific modulus are high. The main use of carbon fiber is as a reinforcing material to be compounded with resins, metals, ceramics, and carbon to manufacture advanced composite materials.

[0003] In the process of carbon fiber production, the raw silk is woven into cloth by a weft knitting machine, then sent into a pre-oxidation furnace for pre-oxidation treatment, and then sent into a low-temperature carbonization furnace for carbonization treatment. After carbonization treatment, it is sent into a carbon tube furnace for graphitization treatment. The carbon fiber obtained after graphitization treatment is sent to an epoxy resin treatment bath for solution infiltration treatment with dilute epoxy resin after non-destructive inspection, so that the obtained unidirectional non-woven carbon fiber cloth has good transverse adhesion, which is convenient for operation during use. The treated non-woven cloth enters a solvent dryer to evaporate the solvent, and then is subjected to non-destructive inspection again to obtain the finished carbon fiber.

[0004] The oxidation process is an important stage in the carbon fiber preparation process that connects the organic-inorganic structure transformation. From the perspective of structure transformation, it can also be called a thermal stabilization process. Its implementation method is to perform heat treatment on the raw silk in a thermal environment with a certain temperature gradient in the air for a long time to make it into a fiber with a heat-resistant stabilized structure. During this process, natural fresh air is usually introduced, and the air environment is heated by a heater installed in the oxidation furnace, consuming a large amount of electric energy, while the high-temperature waste gas generated by the incinerator is not effectively utilized.

[0005] In view of this, the present utility model is specifically proposed. Content of the Utility Model

[0006] The technical problem to be solved by the present utility model is to overcome the deficiencies of the prior art and provide a carbon fiber waste heat recovery device, which preheats the fresh air entering the oxidation furnace and reduces the power consumption and consumption of subsequent electric heating.

[0007] To solve the above technical problem, the basic concept of the technical solution adopted by the present utility model is:

[0008] A carbon fiber waste heat recovery device includes a direct-fired incinerator T0, a waste heat boiler, and an oxidation furnace. The direct-fired incinerator T0 is connected to the waste heat boiler through a fresh air heat exchange device, and the fresh air heat exchange device is also connected to the oxidation furnace. An air flow channel for heat exchange is provided inside the fresh air heat exchange device. The intake end of the first air flow channel is connected to the direct-fired incinerator T0, and the outlet end is connected to the waste heat boiler. The intake end of the second air flow channel is connected to a supply air fan to supply fresh air, and the outlet end is connected to the oxidation furnace. The first air flow channel and the second air flow channel are hermetically isolated and cross-flow for heat exchange. Further, the fresh air heat exchange device includes a box body, which is in a hollow plate-like structure. A number of fresh air pipes of the same size are provided in the first air flow channel along the second air flow direction, and the distance between adjacent fresh air pipes is the same.

[0009] Further, two lining plates are provided inside the fresh air heat exchange device. A number of through holes are provided on the lining plates, and the number of through holes is the same as the number of fresh air pipes. The two lining plates are respectively arranged at both ends of the fresh air pipes. The fresh air pipes pass through the through holes and are hermetically connected to the lining plates. The outside of the fresh air pipes forms the first air flow channel, and the inside of the fresh air pipes forms the second air flow channel.

[0010] Further, a first opening and a second opening are respectively provided in the first air flow channel along the high-temperature flue gas flow direction. The first opening is connected to the flue gas outlet of the incinerator, and the second opening is connected to the waste heat boiler. A third opening and a fourth opening are respectively provided in the second air flow channel along the fresh air flow direction. The third opening is connected to the supply air fan, and the fourth opening is connected to the oxidation furnace.

[0011] Further, expansion compensators are provided at both ends of the ventilation pipe.

[0012] Further, a heat insulation layer is provided outside the fresh air heat exchange device.

[0013] Further, the first opening extends obliquely and expansively along the flue gas flow direction to slow down the air flow velocity.

[0014] Further, the second opening extends obliquely and narrowingly along the flue gas flow direction to increase the air flow velocity.

[0015] Further, the third opening extends obliquely and expansively along the fresh air flow direction to slow down the air flow velocity.

[0016] Further, the fourth opening extends obliquely and narrowingly along the fresh air flow direction to accelerate the air flow velocity.

[0017] After adopting the above technical solution, the present utility model has the following beneficial effects compared with the prior art:

[0018] 1. The utility model is connected between an incinerator and a waste heat boiler through a fresh air heat exchange device, and the fresh air heat exchange device is further communicated with an oxidation furnace. The high-temperature flue gas of the incinerator exchanges heat with fresh air in the fresh air heat exchange device, and the preheated fresh air is conveyed to the oxidation furnace, reducing the consumption of the heating device in the oxidation furnace for oxidation heat exchange, improving the heat recovery utilization rate, and increasing the service life of the electric heater;

[0019] 2. The utility model also increases the heat exchange area, enhances the heat exchange efficiency, fully exchanges heat, and saves energy and reduces emissions through a plurality of fresh air pipes arranged in the first cavity;

[0020] 3. The utility model slows down the inflow speed of flue gas and fresh air and speeds up the outflow speed of the flue gas after heat exchange through the inclined first opening, second opening, and third opening, enabling the high-temperature flue gas and fresh air to fully exchange heat in the air flow channel of the heat exchange device, and the flue gas after heat exchange can flow out quickly, improving production efficiency, further saving energy and reducing emissions, controlling the reduction of waste discharge temperature, and saving electric energy consumption.

[0021] The following further describes in detail the specific implementation manners of the utility model with reference to the accompanying drawings. Description of the Drawings

[0022] The accompanying drawings, as a part of the utility model, are used to provide a further understanding of the utility model. The schematic embodiments of the utility model and their descriptions are used to explain the utility model, but do not constitute an improper limitation to the utility model. Obviously, the accompanying drawings in the following description are only some embodiments, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts. In the drawings:

[0023] Figure 1 is the main cross-sectional view of the fresh air heat exchange device of the utility model;

[0024] Figure 2 is the right cross-sectional view of the fresh air heat exchange device of the utility model;

[0025] Figure 3 is the top cross-sectional view of the fresh air pipe in the fresh air heat exchange device of the utility model.

[0026] In the figure: 1. First opening; 2. Liner; 3. Second opening; 4. Third opening; 5. Fourth opening; 6. Fresh air pipe; 7. Expansion compensator; 8. Thermal insulation layer.

[0027] It should be noted that these drawings and text descriptions are not intended to limit the concept scope of the utility model in any way, but to illustrate the concept of the utility model to those skilled in the art by referring to specific embodiments. Specific Embodiments

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the following will clearly and completely describe the technical solutions in the embodiments in conjunction with the accompanying drawings in the embodiments of the present utility model. The following embodiments are used to illustrate the present utility model but are not intended to limit the scope of the present utility model.

[0029] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present utility model.

[0030] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0031] As Figures 1 to 3 shown, a carbon fiber waste heat recovery device disclosed by the present utility model includes a direct-fired combustion furnace T0, a waste heat boiler, and an oxidation furnace. The direct-fired combustion furnace T0 is connected to the waste heat boiler through a fresh air heat exchange device. The fresh air heat exchange device is also connected to the oxidation furnace. An air flow channel for heat exchange is provided inside the fresh air heat exchange device. The intake end of the first air flow channel is connected to the direct-fired incinerator T0, and the outlet end is connected to the waste heat boiler. The intake end of the second air flow channel is connected to the outside, and the outlet end is connected to the oxidation furnace. The first air flow channel and the second air flow channel are sealed and isolated and cross-flow for heat exchange. Through cross-flow heat exchange, the fresh air after heat exchange is introduced into the oxidation furnace, raising the environment of the oxidation furnace, saving the electric energy consumed by the heating device in the oxidation furnace to heat to the required temperature environment for the oxidation environment, extending the service life of the heater, and reducing the power consumption in the carbon fiber production process.

[0032] In a further embodiment, the fresh air heat exchange device includes a box body, and a fresh air duct 6 and a shell channel which are welded to each other. The fresh air duct 6 is cylindrical, and the shell channel is located outside the fresh air duct 6. The shell channel passes through high-temperature flue gas, and fresh air is introduced into the fresh air duct 6. A first air flow channel for passing high-temperature flue gas is arranged inside the fresh air heat exchange device, and a second air flow channel for passing fresh air is arranged. The second air flow channel is located inside the first air flow channel, and air flow heat exchange is carried out. The fresh air after heat exchange is transported into the oxidation furnace, saving the electric energy and time consumed by temperature compensation.

[0033] The fresh air duct 6 is arranged crosswise to the flue gas flow direction, and the angle between the fresh air duct 6 and the flue gas flow direction is greater than 0° and less than or equal to 90°, and the preferred embodiment is 90°.

[0034] In a further embodiment, a lining plate 2 is welded along the inlet of the second air flow channel inside the fresh air heat exchange device. The lining plate 2 is provided with through holes corresponding to the fresh air duct 6. One end of the fresh air duct 6 passes through the through holes and is hermetically connected thereto. The fresh air heat exchange device is separated into a flue gas chamber and a fresh air chamber by the lining plate 2, preventing the flue gas mixed impurities from entering the fresh air chamber and entering the oxidation furnace through the second air flow channel to affect the production quality. The fresh air duct 6 is located in the flue gas chamber, and a second air flow channel is formed inside the fresh air duct 6. There are several fresh air ducts 6, and the distance between adjacent fresh air ducts 6 is the same. The number of through holes on the lining plate 2 is the same as the number of fresh air ducts 6. The heat receiving area is increased by several fresh air ducts 6 of the same size, and the heat exchange efficiency is improved.

[0035] In a further embodiment, along the high-temperature flue gas flow direction, a first opening 1 and a second opening 3 are respectively formed on both sides of the fresh air heat exchange device. The first opening 1 is communicated with the air outlet of the direct-fired combustion furnace T0, and the second opening 3 is communicated with the waste heat boiler. Along the fresh air flow direction, a third opening 4 and a fourth opening 5 are formed. The third opening 4 is communicated with the air supply fan, and the fourth opening 5 is communicated with the oxidation furnace. The lining plate 2 is arranged on the side close to the third opening 4.

[0036] In a further embodiment, the first opening 1 extends in a conical expansion along the flue gas flow direction, so that the flow rate of the flue gas entering the flue gas chamber is reduced, and the heat exchange time of the high-temperature flue gas is prolonged, enabling it to be fully and quickly heated. The second opening 3 extends in a conical reduction along the flue gas flow direction, so that the heat-exchanged flue gas quickly flows out of the flue gas chamber. The third opening 4 extends in a conical expansion along the fresh air flow direction, so that the flow rate of the fresh air entering the fresh air chamber is reduced, and the duration of the fresh air in the fresh air channel is prolonged, enabling it to fully exchange heat with the high-temperature flue gas, improving the thermal energy utilization rate, and saving energy and reducing emissions.

[0037] A further implementation is that an expansion compensator 7 is provided on the fresh air duct 6, and the expansion compensator 7 is provided at both ends of the fresh air duct 6 to compensate for the expansion and contraction of the duct caused by temperature changes, protect the safe operation of the duct, and avoid affecting the heat exchange efficiency and safety problems due to excessive temperature during the heat exchange process.

[0038] A further implementation is that a heat insulation layer 8 is also provided outside the box body, surrounding the side walls of the box body where there are no air duct openings, to prevent the natural loss of heat of the high-temperature flue gas in the first air flow channel and affect the heat exchange efficiency.

[0039] In the implementation of the present utility model, the high-temperature flue gas flows from the direct-fired combustion furnace T0 into the fresh air heat exchange device and then into the waste heat boiler. The fresh air heat exchange device is provided with an inlet for introducing fresh air, and the fresh air after heat exchange is connected to the oxidation furnace.

[0040] After the high- and low-carbon furnace waste gas is burned in the direct-fired incinerator, it is heat-exchanged and recovered through the fresh air heat exchange device, then enters the waste heat boiler, and the fresh air after heat exchange enters the oxidation furnace, increasing the heat recovery power of preheating the fresh air in the oxidation furnace, reducing the waste gas outlet temperature, and improving the heat recovery efficiency.

[0041] The fresh air is introduced into the oxidation furnace through the heat exchanger and exchanges heat with the high-temperature waste gas, heating the fresh air temperature to 230 °C. The waste gas temperature of the incinerator is reduced from 800 °C to 500 °C through the fresh air heat exchange device, increasing the initial temperature of the fresh air in the oxidation furnace, reducing the power consumption of the electric heater, increasing the service life of the electric heater, and reducing the power consumption.

[0042] The above are only the preferred embodiments of the present utility model, and do not impose any form of limitation on the present utility model. Although the present utility model has been disclosed above with the preferred embodiments, it is not intended to limit the present utility model. Any person skilled in the art of this patent, without departing from the scope of the technical solution of the present utility model, can make some changes or modifications to the above-mentioned technical content as equivalent embodiments of equivalent changes. The implementation schemes in the above embodiments can also be further combined or replaced. However, as long as it does not depart from the content of the technical solution of the present utility model, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present utility model still fall within the scope of the present utility model.

Claims

1. A carbon fiber waste heat recovery device, comprising a direct-fired incinerator, a waste heat boiler and an oxidation furnace, characterized in that: The direct-fired incinerator is connected to the waste heat boiler via a fresh air heat exchange device, and the fresh air heat exchange device is also connected to the oxidation furnace. A first air flow channel and a second air flow channel for heat exchange are provided inside the fresh air heat exchange device. The air inlet end of the first air flow channel is connected to the direct-fired incinerator, and the air outlet end is connected to the waste heat boiler. The air inlet end of the second air flow channel is connected to the air supply fan to supply fresh air, and the air outlet end is connected to the oxidation furnace. The first air flow channel and the second air flow channel are sealed and isolated, and cross-flow is used for heat exchange; The fresh air heat exchange device comprises a box body, the box body is a hollow plate-shaped structure, a plurality of fresh air ducts (6) of the same size are arranged along the second air flow direction in the first air flow channel, and the spacing between adjacent fresh air ducts (6) is the same; Two lining plates (2) are provided inside the fresh air heat exchange device, and a plurality of through holes are provided on the lining plates (2), the number of the through holes being the same as the number of the fresh air duct (6), the two lining plates (2) are respectively arranged at both ends of the fresh air duct (6), the fresh air duct (6) passes through the through holes and is sealedly connected to the lining plates (2), the outside of the fresh air duct (6) forms a first air flow channel, and the inside of the fresh air duct (6) forms a second air flow channel.

2. The carbon fiber waste heat recovery device according to claim 1, characterized in that: The first air flow channel is provided with a first opening (1) and a second opening (3) along the air flow direction of the high-temperature flue gas, the first opening (1) is connected to the flue gas outlet of the direct-fired incinerator, the second opening (3) is connected to the waste heat boiler, and the second air flow channel is provided with a third opening (4) and a fourth opening (5) along the fresh air flow direction, the third opening (4) is connected to the air supply fan, and the fourth opening (5) is connected to the oxidation furnace.

3. The carbon fiber waste heat recovery device according to claim 2, characterized in that: The first airflow channel extends obliquely and expands from the first opening (1) along the direction of smoke flow.

4. The carbon fiber waste heat recovery device according to claim 3, characterized in that: The first airflow channel extends obliquely and narrows along the smoke flow direction toward the second opening (3), and the smoke flow cross section at the second opening (3) is smaller than the smoke flow cross section at the first opening (1).

5. The carbon fiber waste heat recovery device according to claim 4, characterized in that: The second air flow channel extends obliquely and expands from the third opening (4) along the fresh air flow direction.

6. The carbon fiber waste heat recovery device according to claim 5, characterized in that: The second air flow channel extends in an inclined manner and narrows along the fresh air flow direction toward the fourth opening (5), and the fresh air flow cross section at the fourth opening (5) is larger than the fresh air flow cross section at the third opening (4).

7. A carbon fiber waste heat recovery device according to any one of claims 2 to 6, characterized in that: Expansion compensators (7) are provided at both ends of the fresh air duct (6).

8. The carbon fiber waste heat recovery device according to claim 7, characterized in that: A thermal insulation layer (8) is provided on the outside of the fresh air heat exchange device.

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