JP2014159658A - Heat treatment furnace, and heat treatment method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat treatment furnace into the heat treatment chamber of which outdoor air is prevented from flowing so that uniformity of a temperature distribution in the heat treatment chamber can be improved and the amount of heat energy in the heat treatment furnace can be reduced, and to provide a method for producing a carbon fiber by using the heat treatment furnace.SOLUTION: The horizontal heat treatment furnace has the heat treatment chamber and openings which are formed on the lateral sides of the heat treatment chamber and through each of which an object, that is to be treated and has a continuous shape, is introduced or derived. In the concrete, the heat treatment chamber having a circulating hot air supply port through which a heating gas is supplied to the direction perpendicular to the traveling direction of the object to be treated and a circulating hot air discharge port through which the heating gas in the heat treatment chamber is discharged to the side opposed to the circulating hot air supply port is arranged, a seal chamber is arranged for restraining the heating gas from leaking from the heat treatment chamber, a seal buffer chamber is arranged on both outsides of the seal chamber, and hot air blowing nozzles are arranged in the seal chamber so that hot air is blown toward the direction of the heat treatment chamber in parallel to the object to be treated and the blown hot air is made to flow into the heat treatment chamber from the openings through each of which the object to be treated is introduced or derived.

Description

本発明は、熱処理炉、およびそれを用いた熱処理方法、とくに炭素繊維の製造に用いて好適な熱処理炉および炭素繊維の製造方法に関する。   The present invention relates to a heat treatment furnace and a heat treatment method using the same, and more particularly to a heat treatment furnace suitable for use in the production of carbon fibers and a method for producing carbon fibers.

従来の熱処理炉、特に炭素繊維の製造に用いられる熱処理炉としては、熱処理室の上面に設けた循環熱風供給口および下面に設けた循環熱風排出口と、熱処理室の側方側に被処理物を導出入する開口部とを有し、熱処理室内で被処理物を水平方向に走行させながら、その被処理物に上方から循環熱風を吹き付けて熱処理するようにした熱処理炉が知られている（例えば、特許文献１参照）。   Conventional heat treatment furnaces, particularly heat treatment furnaces used for the production of carbon fiber, include a circulating hot air supply port provided on the upper surface of the heat treatment chamber, a circulating hot air discharge port provided on the lower surface, and an object to be processed on the side of the heat treatment chamber. There is known a heat treatment furnace having an opening through which heat treatment is performed by blowing a circulating hot air from above on the object to be processed while the object is traveling in the horizontal direction in the heat treatment chamber ( For example, see Patent Document 1).

ここでいう水平方向とは、地面に対して略平行となる方向のことである。また、熱処理室の両側で被処理物を支えるガイドローラに段差があるなどの原因で、糸条の走行方向が地面に対して傾斜しても、被処理物が熱処理室の向かい合う２側面に渡してあれば、略平行といえる。   Here, the horizontal direction is a direction substantially parallel to the ground. Moreover, even if the running direction of the yarn is inclined with respect to the ground due to a difference in the guide rollers that support the workpiece on both sides of the heat treatment chamber, the workpiece is passed to the two opposite sides of the heat treatment chamber. If so, it can be said to be substantially parallel.

このような熱処理炉において、例えばそれが耐炎化炉である場合、ポリアクリロニトリル系の前駆体繊維からなる糸条を、複数糸条の水平面内において所定のピッチを保ちながら並列させて熱処理室内に導入、かつ、熱処理室の両側に設置されたガイドローラによって走行方向を反転されながら熱処理室内への出入を繰り返し、熱処理室の上下方向においても所定のピッチを保ちながら走行し、耐炎化処理される。   In such a heat treatment furnace, for example, if it is a flameproofing furnace, yarns made of polyacrylonitrile-based precursor fibers are introduced in parallel in a horizontal plane of a plurality of yarns while maintaining a predetermined pitch. In addition, the guide rollers installed on both sides of the heat treatment chamber are repeatedly moved in and out of the heat treatment chamber while the running direction is reversed, and the vehicle is run while maintaining a predetermined pitch in the vertical direction of the heat treatment chamber to be flameproofed.

しかしながら、この形式の熱処理炉では、被処理物が熱処理炉を出入りする段数を上げるなどの手段によって、大型化した場合に、熱処理室の上方に設けた被処理物を導出入する開口部からは熱処理室内の熱風が漏れ出し、熱処理室の下方に設けた開口部からは、低温外気の漏れ込みが生じる。このように、外気が高温の熱処理室内に流入すると同熱処理室内の温度が低下し、熱処理室の加熱エネルギー量の増大と、被処理物の品質の低下を招いてしまう。   However, in this type of heat treatment furnace, when the object to be processed is enlarged by means such as increasing the number of stages for entering and exiting the heat treatment furnace, the opening provided for the object to be processed above and below the heat treatment chamber is introduced from the opening. Hot air in the heat treatment chamber leaks out, and low temperature outside air leaks from an opening provided below the heat treatment chamber. As described above, when the outside air flows into the high temperature heat treatment chamber, the temperature in the heat treatment chamber decreases, leading to an increase in the amount of heating energy in the heat treatment chamber and a decrease in the quality of the workpiece.

このため、上述の問題を解決するために、例えば、被処理物を導出入する開口部の外側に、外気吹出口を有するエアノズルを設け、その吹出口から被処理物に向かって外気を吹き付けるエアカーテン手段を有することで外気の流入を防止し、熱処理室内の温度均一性に優れた熱処理炉が提案されており（特許文献２、３参照）、エアカーテンのガスとして熱風を使用する方法も提案されている（特許文献４参照）。   For this reason, in order to solve the above-mentioned problem, for example, an air nozzle having an outside air outlet is provided outside the opening through which the workpiece is introduced and introduced, and air that blows outside air toward the workpiece from the outlet is provided. Heat treatment furnaces that prevent inflow of outside air by having curtain means and have excellent temperature uniformity in the heat treatment chamber have been proposed (see Patent Documents 2 and 3), and a method of using hot air as the gas for the air curtain is also proposed. (See Patent Document 4).

また、熱処理室内の開口部の上下に熱風吹出ノズルを設け、熱処理室内方向かつ被処理物に直接あたる形で熱風を吹き付けることで、炉内からの有害ガスの流出を防ぐ方法も提案されている（特許文献５参照）。   In addition, a method has been proposed in which hot air blowing nozzles are provided above and below the opening in the heat treatment chamber, and hot air is blown in the direction of the heat treatment chamber and directly against the object to be processed, thereby preventing harmful gas from flowing out of the furnace. (See Patent Document 5).

さらに、熱処理室前後方向に１段以上のシール室を設置し、前記シール室の上部に加熱気体排出部および下部に加熱気体導入部を設け、熱処理室の上方の被処理物からシール室へ漏れ出してきた加熱気体をシール室の上部で吸入し、その吸入した加熱気体を循環させてシール室の下部に供給することも開示されている。こうすることで、熱処理室の下方の被処理物出入口では、高温のシール室で吸入した加熱気体が再度炉内へ流入してくるようになり、これにより熱処理室からの加熱気体の漏れ出しを大きく縮小すると共に、熱処理室内への低温の外気流入も抑制している（特許文献６参照）。   Furthermore, one or more seal chambers are installed in the front-rear direction of the heat treatment chamber, a heated gas discharge unit is provided at the upper part of the seal chamber, and a heated gas introduction unit is provided at the lower part, so that leakage from the object to be processed above the heat treatment chamber to the seal chamber occurs. It is also disclosed that the heated gas that has been discharged is sucked in the upper portion of the seal chamber, and the sucked heated gas is circulated and supplied to the lower portion of the seal chamber. By doing so, the heated gas sucked in the high-temperature seal chamber again flows into the furnace at the workpiece inlet / outlet below the heat treatment chamber, thereby leaking the heated gas from the heat treatment chamber. While greatly reducing, the flow of low-temperature outside air into the heat treatment chamber is also suppressed (see Patent Document 6).

特開平１１−１７３７６１号公報Japanese Patent Laid-Open No. 11-173761 特開２００４−１４３６４７号公報JP 2004-143647 A 特開２００８−８１８５９号公報JP 2008-81859 A 特開２００３−３４２８３８号公報JP 2003-342838 A 米国特許第６０２７３３７号明細書US Pat. No. 6,027,337 特開２００７−２８４８４２号公報JP 2007-284842 A

しかしながら、上記特許文献２、３に開示された熱処理炉のように、エアカーテンによるシール性アップでは、外気流入を完全に防止することは出来なかった。また、この方法ではエアノズル製造コストが高価な上、常温のエアーを浴びる度に被処理物の温度が低下し、熱処理室内熱風循環用ヒーター使用電力が増大する。さらに、被処理物が糸条の場合、糸切れ時はエアーにより糸捌けが発生し巻付きが増大し、炉外にガイドローラを配設しても処置仕切れずに生産設備の停止を余儀なくされる問題がある。   However, as in the heat treatment furnaces disclosed in Patent Documents 2 and 3 above, the inflow of outside air could not be completely prevented by improving the sealing performance with the air curtain. Further, in this method, the manufacturing cost of the air nozzle is expensive, and the temperature of the object to be processed is lowered every time the air is exposed to room temperature, and the electric power used by the heater for circulating hot air in the heat treatment chamber is increased. Furthermore, when the material to be processed is a yarn, when the yarn breaks, the yarn will be broken by air and winding will increase, and even if a guide roller is installed outside the furnace, the production facility will be forced to stop without partitioning the treatment. There is a problem.

上記のようにエアカーテンを設ける方法で、特許文献４に開示された熱処理炉のように、エアカーテンのガスとして熱風を用いる場合は、被処理物の温度低下は防げるものの、炉外に熱風吹出ノズルを設けているため、熱風により炉外の温度が上昇し、作業環境が悪化する。また、特許文献５に開示された熱処理炉では、炉内に熱風吹出ノズルを設けており、炉外の作業環境悪化はある程度防げるものの、熱風として、熱処理炉内ガスを利用し、熱風を被処理物に直接吹き付けるため、被処理物が振動し開口部の縁に擦れて痛んでしまう問題がある。また、処理が耐炎化の場合、耐炎化処理の際に発生したタールやシリカが含まれており、エアカーテンの熱風とともにタールやシリカも被処理物に直接吹き付けられて付着することがある。タールやシリカが被処理物に付着すると、そこが欠陥になって糸切れを起こしたり、強度低下を引き起こしたりするので、最終的に得られる炭素繊維の品質が低下する。   When hot air is used as the gas of the air curtain as in the heat treatment furnace disclosed in Patent Document 4 by the method of providing the air curtain as described above, the temperature of the object to be treated can be prevented, but hot air is blown out of the furnace. Since the nozzle is provided, the temperature outside the furnace rises due to hot air, and the working environment deteriorates. Further, in the heat treatment furnace disclosed in Patent Document 5, a hot air blowing nozzle is provided in the furnace, and although the working environment outside the furnace can be prevented to some extent, the gas inside the heat treatment furnace is used as hot air to treat the hot air. Since the object is sprayed directly, there is a problem that the object to be processed vibrates and rubs against the edge of the opening. Further, when the treatment is flameproof, tar and silica generated during the flameproofing treatment are included, and the tar and silica may be directly blown onto the object to be treated together with the hot air of the air curtain. When tar or silica adheres to an object to be treated, it becomes a defect and causes yarn breakage or strength reduction, so that the quality of the finally obtained carbon fiber is deteriorated.

上記特許文献６に開示された熱処理炉のように、熱処理室前後方向にシール室を設置する方法では、シール室内の加熱気体を循環させることで加熱気体中のタール成分やシリカ等の不純物が濃縮してしまい、時間と共に被処理物の品質および品位が低下してしまう問題点があった。   In the method of installing the seal chamber in the longitudinal direction of the heat treatment chamber as in the heat treatment furnace disclosed in Patent Document 6, impurities such as tar components and silica in the heated gas are concentrated by circulating the heated gas in the seal chamber. As a result, there is a problem that the quality and quality of the object to be processed deteriorate with time.

本発明は前記課題解決をするために次の構成を有する。   The present invention has the following configuration in order to solve the above problems.

（１）熱処理室と、熱処理室の側方側に連続した形態の被処理物を導出入する開口部を有する横型熱処理炉において、前記被処理物の走行方向に対して垂直方向に加熱気体を供給する循環熱風供給口と、前記循環熱風供給口と対向する側に熱処理室内の加熱気体を排出する循環熱風排出口を有する熱処理室と、前記熱処理室からの加熱気体の漏れ出しを抑制するためのシール室と、前記シール室の両外側にシールバッファ室を設けており、前記シール室内に、前記被処理物と平行で前記熱処理室方向に熱風を吹き付け、前記被処理物を導出入する開口部から熱処理室内へ熱風が流入するように、熱風吹出ノズルを設けたことを特徴とする横型熱処理炉。   (1) In a horizontal heat treatment furnace having a heat treatment chamber and an opening through which a workpiece to be processed in a continuous form is introduced to the side of the heat treatment chamber, a heating gas is perpendicular to the traveling direction of the workpiece. In order to suppress the leakage of heated gas from the heat treatment chamber, the heat treatment chamber having a circulation hot air supply port to be supplied, a circulation hot air discharge port for discharging the heated gas in the heat treatment chamber on the side facing the circulation hot air supply port A seal buffer chamber on both outer sides of the seal chamber, and an opening through which hot air is blown in the direction of the heat treatment chamber in parallel to the object to be processed and the object to be processed is led in and out of the seal chamber A horizontal heat treatment furnace characterized in that a hot air blowing nozzle is provided so that hot air flows from the section into the heat treatment chamber.

（２）前記熱風吹出ノズルからシール室内に導入する熱風は、新鮮外気を加熱したものであって、新鮮外気加熱装置の下流側の熱処理炉に供給する新鮮外気から分枝した配管より供給されることを特徴とする、（１）の横型熱処理炉。   (2) The hot air introduced into the seal chamber from the hot air blowing nozzle is obtained by heating fresh outside air, and is supplied from a pipe branched from the fresh outside air supplied to the heat treatment furnace on the downstream side of the fresh outside air heating device. (1) The horizontal heat processing furnace characterized by the above-mentioned.

（３）前記新鮮外気を加熱する手段として、排ガス処理設備の廃熱を利用する熱交換器を利用することを特徴とする、（２）の横型熱処理炉。   (3) The horizontal heat treatment furnace according to (2), wherein a heat exchanger that uses waste heat of an exhaust gas treatment facility is used as means for heating the fresh outside air.

（４）（２）または（３）の横型熱処理炉を用い、連続した形態の被処理物であるポリアクリロニトリル系繊維束を酸化性の加熱気体中で耐炎化処理する工程を有する、耐炎化繊維の製造方法。   (4) A flameproof fiber having a step of flameproofing a polyacrylonitrile fiber bundle, which is an object to be treated in a continuous form, in an oxidizing heating gas using the horizontal heat treatment furnace of (2) or (3) Manufacturing method.

（５）（４）の方法で製造される耐炎化繊維を、不活性雰囲気中で炭素化処理する工程を有する、炭素繊維の製造方法。   (5) A method for producing carbon fiber, comprising a step of carbonizing the flameproof fiber produced by the method of (4) in an inert atmosphere.

本発明は、外気が熱処理室内へ流入しうる被処理物が導出入する開口部の外側から、該熱処理室内へ熱風を吹き付けることにより外気の流入を防止し、エネルギー使用量の削減により、熱処理炉、特に耐炎化炉に適用したときに炭素繊維生産コストダウンが可能となる。   The present invention prevents the inflow of the outside air by blowing hot air into the heat treatment chamber from the outside of the opening through which the workpiece into which the outside air can flow into the heat treatment chamber is introduced, and the heat treatment furnace reduces the amount of energy used. In particular, the carbon fiber production cost can be reduced when applied to a flameproofing furnace.

本発明の代表的な実施例である熱処理炉を耐炎化炉に適用したときの側面図である。It is a side view when the heat processing furnace which is a typical Example of this invention is applied to a flame-proofing furnace. 図１に示した熱処理炉を耐炎化炉に適用したときの要部の詳細面図である。It is a detailed surface view of the principal part when the heat processing furnace shown in FIG. 1 is applied to a flame-proofing furnace. 従来の熱処理炉を耐炎化炉に適用したときの側面図である。It is a side view when the conventional heat processing furnace is applied to a flameproofing furnace. 従来の熱処理炉を耐炎化炉に適用したときの熱収支図である。It is a heat balance figure when the conventional heat processing furnace is applied to a flameproofing furnace.

以下に本発明の一実施形態として、炭素繊維の製造に用いる耐炎化炉として使用する場合を、図面を参照しながら説明する。   Hereinafter, as one embodiment of the present invention, a case where it is used as a flameproofing furnace used in the production of carbon fiber will be described with reference to the drawings.

図３は、従来の耐炎化炉の一例を示す概略構成図である。   FIG. 3 is a schematic configuration diagram showing an example of a conventional flameproofing furnace.

この熱処理炉１は、シート状に引き揃えられた複数の線状の被処理物Ａが出入りする熱処理室２の前後にシール室３と、さらにその外側にシールバッファ室４が設置されている。   The heat treatment furnace 1 is provided with a seal chamber 3 in front of and behind a heat treatment chamber 2 through which a plurality of linear workpieces A arranged in a sheet shape enter and exit, and a seal buffer chamber 4 on the outside thereof.

前記熱処理室２は、被処理物Ａが出入りする開口部１８を複数段有し、前記開口部を通して両外側に備えられた複数の折返しガイドローラ１９を介して被処理物を複数回熱処理する熱処理炉であって、前記被処理物の走行方向に対して垂直方向に熱風を供給する循環熱風供給口と、前記循環熱風供給口と対向する側に熱処理室内の熱風を排出する循環熱風排出口を有し、前記循環熱風排出口と供給口は気体加熱のための熱処理室循環熱風ヒーター６および熱処理室循環熱風ファン７を有する熱処理室循環熱風流路５により連結され、前記熱処理室循環熱風流路５の途中には新鮮熱風導入のための導入部および循環熱風を排出するための排ガス処理設備行き流路１６を設けている。   The heat treatment chamber 2 has a plurality of openings 18 through which the object A enters and exits, and heat-treats the object to be processed a plurality of times through a plurality of folding guide rollers 19 provided on both outer sides through the opening. A circulating hot air supply port for supplying hot air in a direction perpendicular to the traveling direction of the workpiece, and a circulating hot air discharge port for discharging hot air in the heat treatment chamber on the side facing the circulating hot air supply port. The circulation hot air discharge port and the supply port are connected by a heat treatment chamber circulation hot air passage 5 having a heat treatment chamber circulation hot air heater 6 and a heat treatment chamber circulation hot air fan 7 for gas heating, and the heat treatment chamber circulation hot air passage 5 is provided with an introduction part for introducing fresh hot air and a flow path 16 for exhaust gas treatment equipment for discharging the circulating hot air.

前記新鮮熱風は排ガス処理設備１３の廃熱を利用して熱交換器１４を介して予備加熱され、新鮮熱風導入流路１５を通して前記熱処理室２に連結している熱処理室循環熱風流路５へ導入される。この新鮮熱風の温度設定は、新鮮熱風と、熱処理室循環気体が混合されて、熱処理室循環熱風ファン７によって熱処理炉に導入されるときの温度が、熱処理の温度を超えない範囲で高温であるほど気体加熱のための熱処理室循環熱風ヒーター６の負荷を低減できる。   The fresh hot air is preheated through the heat exchanger 14 using waste heat of the exhaust gas treatment facility 13 and is supplied to the heat treatment chamber circulation hot air flow path 5 connected to the heat treatment chamber 2 through the fresh hot air introduction flow path 15. be introduced. The temperature setting of the fresh hot air is such that the temperature when the fresh hot air and the heat treatment chamber circulation gas are mixed and introduced into the heat treatment furnace by the heat treatment chamber circulation hot air fan 7 does not exceed the temperature of the heat treatment. Thus, the load of the heat treatment chamber circulating hot air heater 6 for gas heating can be reduced.

シール室３も同様に、被処理物Ａが出入りする開口部を複数段有し、前記被処理物Ａの走行方向に対して垂直方向に熱風を供給する循環熱風供給口と、前記循環熱風供給口と対向する側に熱処理室内の熱風を排出する循環熱風排出口を有し、前記循環熱風排出口と供給口は気体加熱のためのシール室循環熱風ヒーター９およびシール室循環熱風ファン１０を有するシール室循環熱風流路８により連結されている。   Similarly, the sealing chamber 3 has a plurality of openings through which the workpiece A enters and exits, a circulating hot air supply port that supplies hot air in a direction perpendicular to the traveling direction of the workpiece A, and the circulating hot air supply. A circulation hot air discharge port for discharging hot air in the heat treatment chamber is provided on the side facing the opening, and the circulation hot air discharge port and the supply port have a seal chamber circulation hot air heater 9 and a seal chamber circulation hot air fan 10 for gas heating. The seal chamber circulation hot air flow path 8 is connected.

シールバッファ室４は、被処理物Ａが出入りする開口部を複数段有し、上部には室内の気体を排出するための排出部を有する。前記排出部にはシールバッファ室排気流路１１を連結し、前記シールバッファ室排気流路１１に設置したシールバッファ室排気ファン１２により室内の熱風を排ガス処理装置１３へ送風する。   The seal buffer chamber 4 has a plurality of stages of openings through which the workpiece A enters and exits, and an upper portion has a discharge portion for discharging the gas in the chamber. A seal buffer chamber exhaust passage 11 is connected to the discharge portion, and hot air in the room is blown to the exhaust gas treatment device 13 by a seal buffer chamber exhaust fan 12 installed in the seal buffer chamber exhaust passage 11.

図１は本発明の一例を示す概略構成図であり、図３に示す熱処理炉の有する前記課題を解決するためのものである。図１の耐炎化炉は、図３の耐炎化炉において、熱処理室開口部の外側にあるシール室内に、被処理物と平行で熱処理室方向に熱風を吹き付ける熱風吹出ノズル２０を設け、外気に代わって熱風が熱処理室内へ流入するように熱風を吹き付けることで、熱処理室内への外気流入を防止し、熱処理室内の温度低下を防止する。さらに、シール室内に熱風吹出ノズル２０を設けることによって、熱風による炉外の温度上昇を押さえ、作業環境の悪化を防止することができる。その際、前記熱風温度は４０℃以上かつ熱処理温度を超えない範囲で高温であることが好ましい。熱風温度を４０℃以上に保つことによって、熱処理室の温度低下を押さえることができ、熱処理室温度以下とすることによって、被処理物Ａが高温の空気に触れて損傷することを防ぐことができる。   FIG. 1 is a schematic configuration diagram showing an example of the present invention, and is for solving the above-described problems of the heat treatment furnace shown in FIG. The flameproofing furnace shown in FIG. 1 is the same as the flameproofing furnace shown in FIG. 3 except that a hot air blowing nozzle 20 that blows hot air in the direction of the heat treatment chamber in parallel with the workpiece is provided in the seal chamber outside the heat treatment chamber opening. Instead, the hot air is blown so that the hot air flows into the heat treatment chamber, thereby preventing the outside air from flowing into the heat treatment chamber and preventing the temperature of the heat treatment chamber from decreasing. Furthermore, by providing the hot air blowing nozzle 20 in the seal chamber, it is possible to suppress the temperature rise outside the furnace due to the hot air and prevent the working environment from deteriorating. In that case, it is preferable that the said hot air temperature is high temperature in the range which is 40 degreeC or more and does not exceed heat processing temperature. By keeping the hot air temperature at 40 ° C. or higher, the temperature drop of the heat treatment chamber can be suppressed, and by making the temperature lower than the heat treatment chamber temperature, the workpiece A can be prevented from being damaged by touching high-temperature air. .

また、熱風として使用する空気は、被処理物Ａの品質低下を防ぐためフィルターを通し埃を十分に除去することが好ましく、熱風の熱源としては、ヒーターにより加熱してもよいが、排ガス処理設備１３の廃熱を利用する熱交換器１４を介して、熱処理室２へ導入される加熱気体を分枝し、その一部を利用することが好ましい。こうすることで、新たな熱源を準備する必要がなくなる。   In addition, air used as hot air is preferably sufficiently filtered to remove dust through a filter in order to prevent deterioration of the quality of the object A. The heat source of the hot air may be heated by a heater, but the exhaust gas treatment facility It is preferable to branch the heated gas introduced into the heat treatment chamber 2 through the heat exchanger 14 that uses the waste heat 13 and use a part thereof. This eliminates the need to prepare a new heat source.

熱風吹出ノズル２０は、熱処理室の外側で、被処理物等に干渉せず、熱処理室内へ熱風を流入させることができる位置に設置することが必要で、シール室の内部に設置する。   The hot air blowing nozzle 20 needs to be installed outside the heat treatment chamber at a position where hot air can flow into the heat treatment chamber without interfering with an object to be processed, and is installed inside the seal chamber.

熱風吹出ノズル２０は、矩形又は円形の断面を持った中空の配管をシール室の幅方向に設置して、被処理物Ａの走行方向と平行の空気流を、熱処理室の方向に吹き出す熱風吹出口２１を有する。熱風吹出口２１の形状は、円形や幅方向にスリット状のものなどが適用できるが、配管側面に等間隔に円形の吹出口を設け、その配管両端から熱風を供給し、吹出口から熱風を噴射する形状が好ましく、高さ方向の位置は、上下隣接する開口部の中央に設置することが好ましい。配管径、吹出口径、吹出口間隔はシール室の幅、熱風風量によって適切に決定すればよいが、配管径は、シール室循環熱風の流れを妨げぬようシール室幅の１／２以下、かつ糸道と糸道の距離の１／２以下とすることが好ましい。さらに、熱処理炉機幅方向において、吹出口からの熱風吹出量を均等化するため、配管中央部にいくにつれ吹出口径を大きくすることが好ましい。   The hot air blowing nozzle 20 is a hot air blowing device in which a hollow pipe having a rectangular or circular cross section is installed in the width direction of the seal chamber, and an air flow parallel to the traveling direction of the workpiece A is blown in the direction of the heat treatment chamber. It has an outlet 21. Although the shape of the hot air outlet 21 can be circular or slit-shaped in the width direction, circular air outlets are provided at equal intervals on the side of the pipe, hot air is supplied from both ends of the pipe, and hot air is supplied from the outlet. The shape to be ejected is preferable, and the position in the height direction is preferably installed at the center of the upper and lower adjacent openings. The pipe diameter, blower outlet diameter, and blower outlet interval may be appropriately determined according to the width of the seal chamber and the amount of hot air, but the pipe diameter is ½ or less of the seal chamber width so as not to obstruct the flow of the seal chamber circulating hot air, and The distance between the yarn path and the yarn path is preferably ½ or less. Furthermore, in order to equalize the amount of hot air blown from the outlet in the heat treatment furnace width direction, it is preferable to increase the outlet diameter toward the center of the pipe.

熱風の吹き付け方向は、開口部に直接吹き付けると、熱処理室内への熱風流入量が増え熱処理室内の温度低下防止効果も大きくなるが、被処理物に熱風が直接吹き付けられ、被処理物が振動し開口部の縁に擦れて痛む恐れがあるため、被処理物には直接吹き付けず、被処理物と平行に熱処理室の壁に向けて吹き付ける必要がある。   When the air is blown directly into the opening, the amount of hot air flowing into the heat treatment chamber increases and the effect of preventing temperature drop in the heat treatment chamber increases, but the hot air is blown directly on the workpiece, causing the workpiece to vibrate. Since there is a risk of rubbing against the edge of the opening, it is necessary to spray toward the wall of the heat treatment chamber in parallel with the object to be processed without directly spraying the object to be processed.

さらに、熱風吹出口２１は外気流入のある開口部にのみ熱風が流入するように設置することが好ましい。それにより、設備費の削減および熱風使用量を最低限に抑えることができる。外気流入位置は、開口部の風向を実測して求めても良いし、数値シミュレーションによって求めても良いが、縦方向に下から１／４以上、２／４未満の高さまでの開口部に対応したシール室内に設置することが好ましい。   Furthermore, it is preferable to install the hot air outlet 21 so that the hot air flows only into the opening where the outside air flows. As a result, the equipment cost can be reduced and the amount of hot air used can be minimized. The outside air inflow position may be obtained by actually measuring the wind direction of the opening, or may be obtained by numerical simulation, but corresponds to the opening from the bottom in the vertical direction to a height of 1/4 or more and less than 2/4. It is preferable to install in a sealed chamber.

本発明の熱処理炉を用いることで、熱処理室内からの加熱気体の漏れ出しと熱処理室への不純物を含有した低温外気の漏れ込みを防ぎ、熱処理室内の温度ムラを小さくすることが可能である。   By using the heat treatment furnace of the present invention, it is possible to prevent leakage of heated gas from the heat treatment chamber and leakage of low-temperature outside air containing impurities into the heat treatment chamber, and to reduce temperature unevenness in the heat treatment chamber.

したがって、前記熱処理炉を用いて、ポリアクリロニトリル系繊維束を、好ましくは２００〜３００℃の、さらに好ましくは２２０〜２７５℃の範囲の酸化性の加熱気体中で耐炎化処理して耐熱性の高い構造へと変換させて、高品質の耐炎化繊維を，経済的に優れたプロセスで製造することができる。   Therefore, using the heat treatment furnace, the polyacrylonitrile fiber bundle is preferably subjected to a flameproof treatment in an oxidizing heating gas in the range of 200 to 300 ° C., more preferably in the range of 220 to 275 ° C., thus providing high heat resistance. By converting to a structure, high-quality flame-resistant fibers can be produced by an economically superior process.

また、好ましくは、前記耐炎化繊維を不活性雰囲気、好ましくは窒素雰囲気中１０００℃以上で炭化することにより、高品質の炭素繊維を安定性して、かつエネルギー使用量を削減して製造することができる。   Preferably, the flame-resistant fiber is carbonized at 1000 ° C. or higher in an inert atmosphere, preferably a nitrogen atmosphere, so that high-quality carbon fiber is stabilized and energy consumption is reduced. Can do.

以下に、数値シミュレーションを用いた実施例により、本発明の効果を説明する。   The effects of the present invention will be described below with reference to examples using numerical simulation.

（実施例）
解析に使用した熱処理炉モデルは、図４に示すように、熱処理室２の前後にシール室３と、さらにその外側にシールバッファ室４が設置されている２次元モデルであり、炉壁はすべて断熱としている。被処理物である糸条は透過率をもつ板で近似し、透過率（糸条の抵抗）は、詳細な糸条モデルによる解析結果から算出した。 (Example)
As shown in FIG. 4, the heat treatment furnace model used for the analysis is a two-dimensional model in which a seal chamber 3 is provided before and after the heat treatment chamber 2, and a seal buffer chamber 4 is further provided outside the heat treatment chamber 2. Insulated. The yarn to be processed was approximated by a plate having a transmittance, and the transmittance (resistance of the yarn) was calculated from the analysis result by a detailed yarn model.

上記モデルにおいて、熱処理室の循環熱風供給条件は、２５５℃、６７，０００Ｎｍ^３／ｈｒ、熱処理室前後のシール室の循環熱風供給条件は、熱処理室前後各々２５５℃、６，８００Ｎｍ^３／ｈｒ、シールバッファ室上部排気流量は、熱処理炉前後各々２０００Ｎｍ^３／ｈｒとして数値シミュレーションを行った。熱風吹出ノズルは、上記モデルにおいて外気流入位置を数値シミュレーションにより求め、外気流入のある開口部の上側に設けた。ノズル形状は円形で、吹出口径３０ｍｍとし、シール室の中央に配置した。熱風の吹き付け方向は糸条と平行方向とし、２５５℃の熱風を吹き付ける。熱風吹き付けの風量は、（１）１，０４０Ｎｍ^３／ｈｒ、（２）１，５６０Ｎｍ^３／ｈｒ、（３）２，６００Ｎｍ^３／ｈｒの３通りの条件で解析を行い、熱風の吹き付け風量による効果の違いも確認した。 In the above model, the circulating hot air supply conditions for the heat treatment chamber are 255 ° C. and 67,000 Nm ³ / hr, and the circulating hot air supply conditions for the seal chambers before and after the heat treatment chamber are 255 ° C. and 6,800 Nm ³ / hr, respectively, before and after the heat treatment chamber. Numerical simulations were performed with the exhaust gas flow rate at the upper part of the seal buffer chamber being 2000 Nm ³ / hr before and after the heat treatment furnace. The hot air blowing nozzle was determined by numerical simulation of the outside air inflow position in the above model and provided above the opening where the outside air flows. The nozzle shape was circular, the outlet diameter was 30 mm, and it was placed in the center of the seal chamber. The direction of blowing hot air is parallel to the yarn, and hot air of 255 ° C. is blown. The amount of hot air blowing is analyzed under ^{three conditions} : (1) 1,040 Nm ³ / hr, (2) 1,560 Nm ³ / hr, (3) 2,600 Nm ³ / hr, and depends on the amount of hot air blowing The difference in effect was also confirmed.

発明の効果は、熱処理炉内への外気の流入等による熱ロスにて判断する。ここで「熱ロス」とは、図４に示すように、熱処理室とシール室で構成する熱風循環系２２において、熱処理室循環系排出熱量をＱ１、熱処理室循環系供給熱量をＱ２、シール室循環系排出熱量をｑ１、シール室循環系供給熱量をｑ２とすると、熱風循環系２２の熱ロスＱを、Ｑ＝（Ｑ１+ｑ１）−（Ｑ２＋ｑ２）で定義する。（図示していないが、本実施例の場合はＱ２、ｑ２にシール室内のノズルから供給される空気熱量を含む）つまり、熱処理室内から出る熱量と入る熱量の差を、熱風漏れ出し２３、外気吸い込み２４による熱ロスと考えることができる。   The effect of the invention is judged by heat loss due to the inflow of outside air into the heat treatment furnace. Here, “heat loss” means that, as shown in FIG. 4, in the hot air circulation system 22 constituted by the heat treatment chamber and the seal chamber, the heat treatment chamber circulation system exhaust heat quantity is Q1, the heat treatment chamber circulation system supply heat quantity is Q2, and the seal chamber. The heat loss Q of the hot air circulation system 22 is defined by Q = (Q1 + q1) − (Q2 + q2), where q1 is the circulation system exhaust heat amount and q2 is the seal chamber circulation system supply heat amount. (In the present embodiment, although not shown, Q2 and q2 include the amount of air heat supplied from the nozzle in the seal chamber.) That is, the difference between the amount of heat emitted from the heat treatment chamber and the amount of heat input is expressed as hot air leakage 23, outside air. It can be considered as a heat loss due to the suction 24.

上記数値シミュレーションにより、本発明による熱処理炉の熱ロスは、熱風風量（１）１，０４０Ｎｍ^３／ｈｒのとき１７９ｋＷ、（２）１，５６０Ｎｍ^３／ｈｒのとき１１７ｋＷ、（３）２，６００Ｎｍ^３／ｈｒのとき３９ｋＷであり、風量が増えると熱ロス削減量も大きくなっている。結果を表１に表す。 From the above numerical simulation, the heat loss of the heat treatment furnace according to the present invention is 179 kW when the hot air flow rate is (1) 1,040 Nm ³ / hr, (2) 117 kW when 1,560 Nm ³ / hr, (3) 2,600 Nm ³ It is 39 kW at / hr, and the heat loss reduction amount increases as the air volume increases. The results are shown in Table 1.

（比較例１）
上記熱処理炉モデルにおいて、熱風吹出ノズルを設けない従来の熱処理炉の場合（図４）の熱ロスを求めた。その結果、熱ロスは３４１ｋＷであった。 (Comparative Example 1)
In the heat treatment furnace model, the heat loss in the case of a conventional heat treatment furnace without a hot air blowing nozzle (FIG. 4) was determined. As a result, the heat loss was 341 kW.

（比較例２）
次に上記熱処理炉モデルにおいて、熱風吹出ノズルを熱処理室内に設けた場合の熱ロスを求めた。熱風吹き付け方向、ノズル設置高さは、実施例と同方向とし、ノズルの位置のみをシール室内から熱処理室内に変更し、シール室の壁から内側に２００ｍｍの位置に設置した。その結果、熱風風量（１）１，０４０Ｎｍ^３／ｈｒのとき２２４ｋＷ、（２）１，５６０Ｎｍ^３／ｈｒのとき２１０ｋＷ、（３）２，６００Ｎｍ^３／ｈｒのとき１８７ｋＷであった。 (Comparative Example 2)
Next, in the heat treatment furnace model, the heat loss when the hot air blowing nozzle was provided in the heat treatment chamber was determined. The hot air blowing direction and the nozzle installation height were the same as those in the example. Only the nozzle position was changed from the seal chamber to the heat treatment chamber, and the nozzle was installed at a position of 200 mm inside from the wall of the seal chamber. As a result, when the hot air volume ^{(1) 1,040Nm 3 / hr 224kW} , (2) 1,560Nm 3 / hr 210kW time was 187kW time ⁽³⁾ 2,600Nm 3 / hr.

（比較例３）
さらに上記熱処理炉モデルにおいて、熱風吹出ノズルをシールバッファ室内、つまり熱風循環系より外側に設けた場合の熱ロスを求めた。熱風吹き付け方向、ノズル設置高さは、実施例と同方向とし、ノズルの位置のみをシール室内からシールバッファ室内に変更し、シール室の壁から外側に１２５ｍｍの位置に設置した。その結果、熱風風量（１）１，０４０Ｎｍ^３／ｈｒのとき２４９ｋＷ、（２）１，５６０Ｎｍ^３／ｈｒのとき２０７ｋＷ、（３）２，６００Ｎｍ^３／ｈｒのとき１２５ｋＷであった。 (Comparative Example 3)
Further, in the heat treatment furnace model, the heat loss was determined when the hot air blowing nozzle was provided outside the seal buffer chamber, that is, outside the hot air circulation system. The hot air blowing direction and nozzle installation height were the same as those in the example, and only the nozzle position was changed from the seal chamber to the seal buffer chamber, and the nozzle was installed at a position of 125 mm outward from the wall of the seal chamber. As a result, the amount of hot air was (1) 1,040 Nm ³ / hr, 249 kW, (2) 1,560 Nm ³ / hr, 207 kW, and (3) 2,600 Nm ³ / hr, 125 kW.

以上より、実施例が、従来の熱処理炉（比較例１）対比最も熱ロス削減効果が高いことがわかった。比較例２からは、熱ロス削減率は、熱処理室内側に直接熱風吹出ノズルを設けるより、熱処理室外側から熱処理室方向へ熱風を吹き付けた方が、熱ロス削減効果は高いことがわかった。また、比較例３も同様に熱ロス削減量は小さく、熱風循環系の外側に熱風吹出ノズルを設置するよりも、熱風循環系の内側であるシール室内に設置することで、最も大きな熱ロス削減効果が得られることがわかった。結果を表１にまとめる。   From the above, it was found that the example had the highest heat loss reduction effect compared with the conventional heat treatment furnace (Comparative Example 1). From Comparative Example 2, it was found that the heat loss reduction rate was higher when the hot air was blown from the outside of the heat treatment chamber toward the heat treatment chamber than when the hot air blowing nozzle was directly provided on the heat treatment chamber side. Similarly, the amount of heat loss reduction in Comparative Example 3 is also small, and the largest heat loss reduction is achieved by installing it in the seal chamber inside the hot air circulation system rather than installing the hot air blowing nozzle outside the hot air circulation system. It turns out that an effect is acquired. The results are summarized in Table 1.

このように、本発明によれば、外気が熱処理室内へ流入しうる、被処理物を導出入する開口部の外側から、同熱処理室内へ熱風を吹き付けることにより、熱処理炉内への外気の流入を遮断することができ、エネルギー使用量の削減により炭素繊維生産コストダウンが可能となる。   As described above, according to the present invention, the outside air can flow into the heat treatment furnace by blowing hot air into the heat treatment chamber from the outside of the opening through which the object to be processed can be introduced and introduced. The carbon fiber production cost can be reduced by reducing the amount of energy used.

１：熱処理炉
２：熱処理室
３：シール室
４：シールバッファ室
５：熱処理室循環熱風流路
６：熱処理室循環熱風ヒーター
７：熱処理室循環熱風ファン
８：シール室内循環熱風流路
９：シール室内循環熱風用ヒーター
１０：シール室内循環熱風用ファン
１１：シールバッファ室排気用流路
１２：シールバッファ室排気用ファン
１３：排ガス処理設備
１４：熱交換器
１５：新鮮熱風導入流路
１６：排ガス処理設備行き流路
１７：新鮮熱風導入用ファン
１８：開口部
１９：ガイドローラ
２０：熱風吹出ノズル
２１：熱風吹出口
２２：熱風循環系
２３：熱風漏れ出し
２４：外気吸い込み
Ｑ１：熱処理室循環系排出熱量
Ｑ２：熱処理室循環系供給熱量
ｑ１：シール室循環系排出熱量
ｑ２：シール室循環系供給熱量
Ａ：被処理物 1: Heat treatment furnace 2: Heat treatment chamber 3: Sealing chamber 4: Seal buffer chamber 5: Heat treatment chamber circulating hot air flow path 6: Heat treatment chamber circulating hot air heater 7: Heat treatment chamber circulating hot air fan 8: Seal chamber circulating hot air flow path 9: Seal Indoor circulation hot air heater 10: Seal indoor circulation hot air fan 11: Seal buffer chamber exhaust flow path 12: Seal buffer chamber exhaust fan 13: Exhaust gas treatment equipment 14: Heat exchanger 15: Fresh hot air introduction flow path 16: Exhaust gas Flow line for processing equipment 17: Fan for introducing fresh hot air
18: Opening 19: Guide roller 20: Hot air blowing nozzle 21: Hot air blowing outlet 22: Hot air circulation system 23: Hot air leakage 24: Outside air suction Q1: Heat treatment chamber circulation system heat release Q2: Heat treatment chamber circulation system heat supply q1: Seal chamber circulation system exhaust heat q2: Seal chamber circulation system heat supply A: Object to be treated

本発明における熱処理炉ならびに熱処理方法は、特に耐炎化処理を必要とする用途に適しており、中でも炭素繊維製造工程において好適なものである。   The heat treatment furnace and the heat treatment method in the present invention are particularly suitable for applications that require flameproofing treatment, and are particularly suitable for the carbon fiber production process.

Claims (5)

熱処理室と、熱処理室の側方側に連続した形態の被処理物を導出入する開口部を有する横型熱処理炉において、前記被処理物の走行方向に対して垂直方向に加熱気体を供給する循環熱風供給口と、前記循環熱風供給口と対向する側に熱処理室内の加熱気体を排出する循環熱風排出口を有する熱処理室と、前記熱処理室からの加熱気体の漏れ出しを抑制するためのシール室と、前記シール室の両外側にシールバッファ室を設けており、前記シール室内に、前記被処理物と平行で前記熱処理室方向に熱風を吹き付け、前記被処理物を導出入する開口部から熱処理室内へ熱風が流入するように、熱風吹出ノズルを設けたことを特徴とする横型熱処理炉。 Circulation for supplying a heating gas in a direction perpendicular to the traveling direction of the workpiece in a horizontal heat treatment furnace having a heat treatment chamber and an opening through which the workpiece to be processed in a continuous form is led to the side of the heat treatment chamber A heat treatment chamber having a hot air supply port, a circulation hot air discharge port for discharging the heated gas in the heat treatment chamber on the side facing the circulation hot air supply port, and a seal chamber for suppressing leakage of the heated gas from the heat treatment chamber Seal buffer chambers are provided on both outer sides of the seal chamber, and hot air is blown into the seal chamber parallel to the object to be processed in the direction of the heat treatment chamber, and heat treatment is performed from an opening through which the object to be processed is led in and out. A horizontal heat treatment furnace provided with a hot air blowing nozzle so that hot air flows into the room. 前記熱風吹出ノズルからシール室内に導入する熱風は、新鮮外気を加熱したものであって、新鮮外気加熱装置の下流側の熱処理炉に供給する新鮮外気から分枝した配管より供給されることを特徴とする、請求項１に記載の横型熱処理炉。 The hot air introduced into the seal chamber from the hot air blowing nozzle is obtained by heating fresh outside air, and is supplied from a pipe branched from fresh outside air supplied to a heat treatment furnace on the downstream side of the fresh outside air heating device. The horizontal heat treatment furnace according to claim 1. 前記新鮮外気を加熱する手段として、排ガス処理設備の廃熱を利用する熱交換器を利用することを特徴とする、請求項２に記載の横型熱処理炉。 The horizontal heat treatment furnace according to claim 2, wherein a heat exchanger that uses waste heat of an exhaust gas treatment facility is used as means for heating the fresh outside air. 請求項２または３に記載の横型熱処理炉を用い、連続した形態の被処理物であるポリアクリロニトリル系繊維束を酸化性の加熱気体中で耐炎化処理する工程を有する、耐炎化繊維の製造方法。 A method for producing flame-resistant fibers, comprising using the horizontal heat treatment furnace according to claim 2 or 3 to flame-treat a polyacrylonitrile fiber bundle, which is an object to be processed in a continuous form, in an oxidizing heating gas. . 請求項４に記載の方法で製造される耐炎化繊維を、不活性雰囲気中で炭素化処理する工程を有する、炭素繊維の製造方法。 The manufacturing method of carbon fiber which has the process of carbonizing the flame-resistant fiber manufactured by the method of Claim 4 in inert atmosphere.

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