CN106480553B - A kind of pre-oxidation device for carbon fiber production - Google Patents
A kind of pre-oxidation device for carbon fiber production Download PDFInfo
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- CN106480553B CN106480553B CN201610926303.5A CN201610926303A CN106480553B CN 106480553 B CN106480553 B CN 106480553B CN 201610926303 A CN201610926303 A CN 201610926303A CN 106480553 B CN106480553 B CN 106480553B
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- oxidation furnace
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- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
- D01F9/00—Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments
- D01F9/08—Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments of inorganic material
- D01F9/12—Carbon filaments; Apparatus specially adapted for the manufacture thereof
- D01F9/14—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments
- D01F9/20—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from polyaddition, polycondensation or polymerisation products
- D01F9/21—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from polyaddition, polycondensation or polymerisation products from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
- D01F9/22—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from polyaddition, polycondensation or polymerisation products from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds from polyacrylonitriles
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Abstract
The invention discloses a kind of pre-oxidation devices for carbon fiber production, belong to carbon fiber production and processing technical field.The pre-oxidation device includes pre-oxidation furnace, air feed system, exhaust system, driving device and temperature measurement control system.Wherein, pre-oxidation furnace is composed in series by the first pre-oxidation furnace and the second pre-oxidation furnace, first pre-oxidation furnace and the second pre-oxidation furnace are respectively provided with several burner hearths arranged in parallel up and down, first pre-oxidation furnace internal furnace temperature gradually rises from bottom to top, and the fire box temperature of the second pre-oxidation furnace 5 gradually rises from top to bottom.Air feed system and exhaust system are connect by pipeline with the burner hearth of the first pre-oxidation furnace and the second pre-oxidation furnace, and driving device is mounted on the both ends of each burner hearth.The features such as pre-oxidation furnace has warm area and temperature gradient distribution reasonable, and heating system temperature is uniform, accurately controls in-furnace temperature and is gradually changed between 100 DEG C 300 DEG C, and temperature control precision, which can guarantee, is not less than ± 0.5 DEG C.
Description
Technical field
The present invention relates to a kind of pre-oxidation devices for carbon fiber production, belong to carbon fiber production and processing technical field.
Background technology
In carbon fibre carbonizing production process to the first step be exactly preoxidation process, the purpose is to make with linear macromolecule
The polyacrylonitrile fibril of chain cannot not be changed into moltenly non-ignitable heat-resisting trapezium structure after high temperature oxidation process, it is made to stand subsequently
High temperature cabonization process and keep fiber condition.
Influence of the preoxidation process to the quality and yield of carbon fiber is very big.The current pre-oxidation type of furnace both domestic and external has interior heat
Formula pre-oxidation furnace, external heating type furnace for preliminary, recirculation furnace, solid-solid heat transfer stove, the pre-oxidation furnace with sulfuric horizon are a variety of, often
Kind of pre-oxidation furnace has the characteristics that respective different according to respectively different technique, and to equip generally existing furnace body close for existing pre-oxidation
Seal phenomena such as bad equal, isothermal region is uneven.Therefore, polyacrylonitrile fibril pre-oxidation characteristic, technique item can be met by being badly in need of one kind
Part and production-scale pre-oxidation furnace.
Invention content
To solve above-mentioned technical problem the present invention provides a kind of pre-oxidation device for carbon fiber production, taken
Technical solution is as follows:
A kind of pre-oxidation device for carbon fiber production, including pre-oxidation furnace, air feed system 2, exhaust system 3, driving
Device 4 and temperature measurement control system.Wherein, pre-oxidation furnace is by 5 series connection group of the first pre-oxidation furnace 1 and the second pre-oxidation furnace
Several burner hearths arranged in parallel up and down are respectively provided at, the first pre-oxidation furnace 1 and the second pre-oxidation furnace 5, in the first pre-oxidation furnace 1
The temperature of fire box temperature upper layer burner hearth is not less than the temperature of lower layer's burner hearth, the fire box temperature lower layer burner hearth of the second pre-oxidation furnace 5
Temperature is not less than the temperature of upper layer burner hearth;Air feed system 2 and exhaust system 3 are pre- by pipeline and the first pre-oxidation furnace 1 and second
The burner hearth of oxidation furnace 5 connects, and driving device 4 is mounted on the both ends of each burner hearth.
Preferably, the heating furnace body of pre-oxidation furnace includes burner hearth 11, the pre-oxidation furnace insulating layer 12 in 11 outside of burner hearth and logical
The pre-oxidation furnace temperature sensor 13 and pre-oxidation furnace heating device 14 that oversampling circuit is connect with temperature measurement control system;Wherein pre-oxidation furnace
Temperature sensor 13 and pre-oxidation furnace heating device 14 are mounted between burner hearth 11 and pre-oxidation furnace insulating layer 12, to realize in burner hearth
Temperature detects and controls.
Preferably, air feed system 2 includes pressure fan 21, the air-supply supervisor 22 being connect with 21 air outlet of pressure fan, with air-supply
22 connection of supervisor and the blowpipe 23 being connect respectively with side in the middle part of each burner hearth of pre-oxidation furnace, blowpipe 23 is close to entrance
Outside is equipped with air blowing control valve 24, supply air sensor 26 and air-supply heater 25 is internally provided in blowpipe 23, in air-supply branch
Ajutage insulating layer 27 is additionally provided with outside pipe 23.
It is highly preferred that supply air sensor 26 and air-supply heater 25 and temperature measurement control system are chain, so as to being supplied
The temperature of wind is controlled.
Preferably, exhaust system 3 is respectively equipped with the first outlet air at the both ends of the first pre-oxidation furnace 1 and the second pre-oxidation furnace 5
Pipe 31 and the second discharge pipe 32, the first discharge pipe 31 and the second discharge pipe 32 with what each burner hearth both ends was connect by going out respectively
Wind branch pipe 33 is connected to.
Preferably, first pre-oxidation furnace, 1 and second pre-oxidation furnace 5 has 7 burner hearths arranged in parallel up and down, silk respectively
Beam 9 is entered by driving device 4 from the bottom of the first pre-oxidation furnace 1, and the top of the second pre-oxidation furnace 5 is entered back by Base top contact
Portion, then drawn by the bottom of the second pre-oxidation furnace 5 by the driving of driving device 4.It can be arranged in each burner hearth continuous integrated
Warm area is heated, the heating warm area of discontinuous discontinuous can also be used.For example, 6 are arranged along its length in a burner hearth
Heat warm area.
Preferably, first pre-oxidation furnace, 1 and second pre-oxidation furnace 5 has 7 burner hearths arranged in parallel up and down respectively, the
The temperature of each layer burner hearth successively increases from bottom to top in one pre-oxidation furnace 1;The temperature of each layer burner hearth is by upper in second pre-oxidation furnace 5
It successively increases downwards.
Preferably, first pre-oxidation furnace, 1 and second pre-oxidation furnace 5 has 7 burner hearths arranged in parallel up and down respectively, the
The temperature of each layer burner hearth is successively increased to layer 6 upwards by the bottom in one pre-oxidation furnace 1, and layer 7 is that temperature is not raised
Constant temperature transition region;The temperature of each layer burner hearth is successively increased by top down to layer 6 in second pre-oxidation furnace 5, layer 7 temperature
The not raised constant temperature transition region of degree.
The advantageous effect that the present invention obtains is:
The pre-oxidation furnace of the present invention is equipped with the heating compensation device chain with control device in furnace body, can accurately control
In-furnace temperature gradually changes between 100 DEG C -300 DEG C, can meet the needs of PAN precursor pre-oxidations reaction well.This is pre-
The warm area and temperature gradient distribution of oxidation furnace are reasonable, and heating system temperature is uniform, and temperature control precision, which can guarantee, is not less than ± 0.5
℃。
Meanwhile the heat-insulating property and energy-efficient performance of the pre-oxidation furnace are good, and furnace outer wall temperature can be made to be no more than 25 DEG C.The stove
Interior heat circulating system air quantity, wind-warm syndrome and wind pressure it is adjustable, exhaust gas can be discharged by dedicated system, will not be revealed to workshop.
Description of the drawings
Fig. 1 is that the present invention first pre-oxidizes furnace body structural schematic diagram.
Fig. 2 is that the present invention second pre-oxidizes furnace body structural schematic diagram.
Fig. 3 is the structural schematic diagram of inventive vent and burner hearth junction.
In figure:1, the first pre-oxidation furnace;2, air feed system;3, exhaust system;4, driving device;5, the second pre-oxidation furnace;
9, tow;11, burner hearth;12, pre-oxidation furnace insulating layer;13, pre-oxidation furnace temperature sensor;14, pre-oxidation furnace heating device;21, air-supply
Machine;22, air-supply supervisor;23, blowpipe;24, control valve;25, heater of blowing;26, supply air sensor;27, ajutage is protected
Warm layer;31, the first discharge pipe;32, the second discharge pipe;33, outlet air branch pipe;101, the first burner hearth;102, the second burner hearth;103, the
Three burner hearths;104, the 4th burner hearth;105, the 5th burner hearth;106, the 6th burner hearth;107, the 7th burner hearth;108, the 8th burner hearth;109,
9th burner hearth;110, the tenth burner hearth;111, the 11st burner hearth;112, the 11st burner hearth;113, the 13rd burner hearth;114, the 14th
Burner hearth.
Specific implementation mode
The present invention is described in further details below in conjunction with the accompanying drawings, but the limit described further below being not intended as to the present invention
It is fixed.
Wherein, Fig. 1 is that the present invention first pre-oxidizes furnace body structural schematic diagram.Fig. 2 is that the present invention second pre-oxidizes furnace body knot
Structure schematic diagram.The direction of arrow is the direction of advance of fibre bundle in Fig. 1 and Fig. 2.Fig. 3 is that inventive vent is connect with burner hearth
The structural schematic diagram at place.The direction of arrow is the flow direction for the hot wind that air feed system provides in Fig. 3.
From Fig. 1-Fig. 3 it is found that the pre-oxidation device includes two pre-oxidation furnaces being connected in series with, i.e. the first pre-oxidation furnace 1
With the second pre-oxidation furnace 5, and the air feed system 2 of wind regime is provided for each pre-oxidation furnace, the exhaust system 3 to scavenge, Gu
It is scheduled on the driving device 4 of pre-oxidation furnace both sides.Meanwhile it being additionally provided with through cable circuit and each component heating element and temperature sensing
The temperature measurement control system of element connection, to realize that whole to pre-oxidation device and each spot temperature accurately controls.
First pre-oxidation furnace 1 is mainly by from upper first burner hearth 101 arranged in parallel, the second burner hearth 102, the successively upwards
Three burner hearths 103, the 4th burner hearth 104, the 5th burner hearth 105, the 6th burner hearth 106 and the 7th burner hearth 107 composition.And the second pre-oxidation furnace
5 mainly by the 8th burner hearth 108 arranged in parallel, the 9th burner hearth 109, the tenth burner hearth 110, the 11st stove successively from the top down
Thorax 111, the 11st burner hearth 112, the 13rd burner hearth 113 and the 14th burner hearth 114 composition.It is designed with drive on the both sides of each burner hearth
Dynamic roller drives tow 9 to advance as driving device 4.In use, the temperature of 101 to the 14th burner hearth 114 of the first burner hearth
Incremented by successively, tow 9 enters from the left side of the first burner hearth of bottom 101 of the first pre-oxidation furnace 1, is drawn by the right side of the 7th burner hearth 107
Go out and enter the left side of the 8th burner hearth 108 of the second pre-oxidation furnace 5, is finally drawn by the right side of the 14th burner hearth 114.It is using
It in the process, also can be by the 7th burner hearth 107 and the 14th burner hearth 114 as temperature-resistant constant temperature transition region.
First pre-oxidation furnace 1 is identical with the length of each burner hearth in the second pre-oxidation furnace 5, and both ends are aligned.In each stove
The centre of thorax is nearby connected to side with the blowpipe 23 of air feed system 2, to realize that wind-force is supplied.Air feed system 2 is equipped with air-supply
Machine 21, and connect with 21 air-supply outlet of pressure fan air-supply supervisor 22, air-supply supervisor 22 respectively with above-mentioned blowpipe 23
Connection.It is equipped with control valve 24 near interconnecting piece of the blowpipe 23 with air-supply supervisor 22, in order to control air output.It is blowing
It is equipped with air-supply heater 25 and supply air sensor 26 (Fig. 3) in branch pipe 23, and is additionally provided with ajutage insulating layer 27 outside tube wall.
In the same manner, pre-oxidation furnace temperature sensor 13 is equipped between each burner hearth 11 and the pre-oxidation furnace insulating layer 12 being wrapped in outside burner hearth 11
With pre-oxidation furnace heating device 14, and above-mentioned heater and sensor pass through cable circuit and temperature measurement control system and practice
Grade detects and controls temperature in air supply pipeline and burner hearth with realizing.Above-mentioned heater and sensor can be used as temperature-compensating
Device and control device, such as computer, the temperature being electrically connected in accurate chain control burner hearth of the furnace body.
It is mounted on exhaust system 3 on each pre-oxidation furnace, exhaust system 3 is by the first discharge pipe 31, the second discharge pipe
32 and 14 outlet air branch pipes 33.Wherein, the first discharge pipe 31 and the second discharge pipe 32 are vertically arranged, and it is each to be mounted on pre-oxidation furnace
The both sides of burner hearth, and by outlet air branch pipe 33 near the both sides endpoint of each burner hearth side or top be connected to, in order to will
The exhaust gas generated in preoxidation process is excluded from furnace body.
Although the present invention is disclosed as above with preferred embodiment, it is not limited to the present invention, any to be familiar with this
The people of technology can do various changes and modification, therefore the protection of the present invention without departing from the spirit and scope of the present invention
Range should be subject to what claims were defined.
Claims (8)
1. a kind of pre-oxidation device for carbon fiber production, including pre-oxidation furnace, air feed system (2), exhaust system (3) drive
Dynamic device (4) and temperature measurement control system, which is characterized in that pre-oxidation furnace is by the first pre-oxidation furnace (1) and the second pre- oxygen
Change stove (5) to be composed in series, the first pre-oxidation furnace (1) and the second pre-oxidation furnace (5) are respectively provided with several stoves arranged in parallel up and down
Thorax, the temperature of the first pre-oxidation furnace (1) internal furnace temperature upper layer burner hearth are not less than the temperature of lower layer's burner hearth, the second pre-oxidation furnace
(5) temperature of fire box temperature lower layer burner hearth is not less than the temperature of upper layer burner hearth;Air feed system (2) and exhaust system (3) pass through
Pipeline is connect with the burner hearth of the first pre-oxidation furnace (1) and the second pre-oxidation furnace (5), and driving device (4) is mounted on each burner hearth
Both ends.
2. pre-oxidation device described in claim 1, which is characterized in that the heating furnace body of pre-oxidation furnace includes burner hearth (11), stove
It pre-oxidation furnace insulating layer (12) on the outside of thorax (11) and is passed by the pre-oxidation furnace temperature that circuit is connect with temperature measurement control system
Sensor (13) and pre-oxidation furnace heating device (14);Wherein pre-oxidation furnace temperature sensor (13) and pre-oxidation furnace heating device (14) installation
Between burner hearth (11) and pre-oxidation furnace insulating layer (12).
3. pre-oxidation device described in claim 1, which is characterized in that air feed system (2) includes pressure fan (21), with pressure fan
(21) air outlet connection air-supply supervisor (22), with air-supply supervisor (22) connect and respectively with each burner hearth medial side of pre-oxidation furnace
The blowpipe (23) of face connection, blowpipe (23) is equipped with air blowing control valve (24) on the outside of entrance, in blowpipe
(23) it is internally provided with supply air sensor (26) and air-supply heater (25), ajutage heat preservation is additionally provided with outside blowpipe (23)
Layer (27).
4. the pre-oxidation device described in claim 3, which is characterized in that supply air sensor (26) and air-supply heater (25) and temperature
It is chain to spend detecting and controlling system.
5. pre-oxidation device described in claim 1, which is characterized in that exhaust system (3) is in the first pre-oxidation furnace (1) and second
The both ends of pre-oxidation furnace (5) are respectively equipped with the first discharge pipe (31) and the second discharge pipe (32), the first discharge pipe (31) and second
Discharge pipe (32) is connected to by the outlet air branch pipe (33) being connect respectively with each burner hearth both ends.
6. pre-oxidation device described in claim 1, which is characterized in that first pre-oxidation furnace (1) and the second pre-oxidation furnace
(5) there are 7 burner hearths arranged in parallel up and down respectively, tow (9) is by driving device (4) from the bottom of the first pre-oxidation furnace (1)
Into, and the top of the second pre-oxidation furnace (5) is entered back by Base top contact, then driven by the second pre- oxygen by driving device (4)
It draws the bottom for changing stove (5).
7. the pre-oxidation device described in claim 6, which is characterized in that first pre-oxidation furnace (1) and the second pre-oxidation furnace
(5) there are 7 burner hearths arranged in parallel up and down respectively, the temperature of each layer burner hearth successively rises from bottom to top in the first pre-oxidation furnace (1)
It is high;
The temperature of each layer burner hearth successively increases from top to bottom in second pre-oxidation furnace (5).
8. the pre-oxidation device described in claim 6, which is characterized in that first pre-oxidation furnace (1) and the second pre-oxidation furnace
(5) have 7 burner hearths arranged in parallel up and down respectively, in the first pre-oxidation furnace (1) temperature of each layer burner hearth by the bottom upwards to
Layer 6 successively increases, and layer 7 is the not raised constant temperature transition region of temperature;The temperature of each layer burner hearth in second pre-oxidation furnace (5)
It is successively increased down to layer 6 by top, the not raised constant temperature transition region of layer 7 temperature.
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Families Citing this family (4)
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CN109402794B (en) * | 2017-08-16 | 2021-05-28 | 中国石油化工股份有限公司 | Apparatus and heat treatment method for weakening skin-core structure in carbon fiber |
CN109402795B (en) * | 2017-08-16 | 2021-05-11 | 中国石油化工股份有限公司 | Pre-oxidation method and equipment for improving mechanical property of carbon fiber |
CN107557909B (en) * | 2017-08-25 | 2020-07-14 | 中国科学院宁波材料技术与工程研究所 | Air oxidation furnace and application thereof |
CN111394835B (en) * | 2020-05-12 | 2024-11-08 | 中国石油化工股份有限公司 | A carbon fiber oxidation furnace |
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JP2007224483A (en) * | 2006-01-30 | 2007-09-06 | Toray Ind Inc | Apparatus for producing carbon fiber bundle and method for producing the same |
CN101684576B (en) * | 2009-07-30 | 2011-06-15 | 合肥日新高温技术有限公司 | Pre-oxidation furnace |
CN102758270B (en) * | 2012-06-21 | 2014-05-21 | 合肥日新高温技术有限公司 | High-performance carbon fiber pre-oxidation furnace |
CN104213254A (en) * | 2014-08-08 | 2014-12-17 | 中国科学院宁波材料技术与工程研究所 | Device to improve temperature field uniformity of pre-oxidation furnace |
CN105506786B (en) * | 2014-10-14 | 2017-12-15 | 中国石油化工股份有限公司 | Carbon fiber pre-oxidizes equipment |
CN104451963B (en) * | 2014-12-29 | 2016-03-23 | 江苏恒神股份有限公司 | Carbon fiber precursor pre-oxidation experimental setup |
JP6217844B2 (en) * | 2015-02-25 | 2017-10-25 | 三菱ケミカル株式会社 | Heat treatment furnace apparatus and carbon fiber bundle manufacturing method |
CN206143365U (en) * | 2016-10-31 | 2017-05-03 | 哈尔滨天顺化工科技开发有限公司 | A oxidation unit in advance for carbon fiber production |
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