JP6865638B2

JP6865638B2 - Rotary kiln and how to drive it

Info

Publication number: JP6865638B2
Application number: JP2017100581A
Authority: JP
Inventors: 正也清水
Original assignee: Kawasaki Jukogyo KK
Current assignee: Kawasaki Motors Ltd
Priority date: 2017-05-22
Filing date: 2017-05-22
Publication date: 2021-04-28
Anticipated expiration: 2037-05-22
Also published as: JP2018194275A

Description

本発明は、外熱式ロータリーキルン及びその運転方法に関する。 The present invention relates to an externally heated rotary kiln and a method of operating the same.

従来から、外熱式のロータリーキルンが知られている。特許文献１は、この種のロータリーキルンを開示する。 Conventionally, an externally heated rotary kiln has been known. Patent Document 1 discloses this type of rotary kiln.

特許文献１のロータリーキルン（炭化炉）は、横置きに設置された外筒内に、当該外筒と同心円状に挿入された内筒（キルンシェル）を備えている。このロータリーキルンでは、内筒に被処理物（乾燥汚泥）を投入して当該内筒を回転させながら、外筒と内筒の間に形成された加熱流路に導入された高温ガスで内筒内の被処理物を間接加熱して低酸素雰囲気で熱分解させることにより、被処理物から可燃性の熱分解ガスと炭化物とを生成する。 The rotary kiln (carbonization furnace) of Patent Document 1 includes an inner cylinder (kiln shell) inserted concentrically with the outer cylinder in an outer cylinder installed horizontally. In this rotary kiln, an object to be treated (dry sludge) is put into an inner cylinder, and while the inner cylinder is rotated, a high-temperature gas introduced into a heating flow path formed between the outer cylinder and the inner cylinder is used inside the inner cylinder. By indirectly heating the object to be treated and thermally decomposing it in a low oxygen atmosphere, flammable pyrolysis gas and carbides are generated from the object to be treated.

上記のような外熱式ロータリーキルンにおいては、ロータリーキルンから発生する熱分解ガスを燃焼炉で燃焼し、その排ガスの一部をロータリーキルンの熱源（高温ガス）として利用することにより、排熱を有効に利用することが行われている。しかしながら、燃焼炉の排ガスには灰や塵などのダストが同伴しており、この排ガスがロータリーキルンの加熱流路に供給されると、内筒の外表面にダストが付着・堆積し、この付着物及び／又は堆積物（以下、「付着物等」と称する）によって内筒の伝熱性能が低下し、その結果、ロータリーキルンの熱効率を低下させることが問題となっている。 In the above-mentioned external heat type rotary kiln, exhaust heat is effectively used by burning the pyrolysis gas generated from the rotary kiln in a combustion furnace and using a part of the exhaust gas as a heat source (high temperature gas) of the rotary kiln. Is being done. However, the exhaust gas from the combustion furnace is accompanied by dust such as ash and dust, and when this exhaust gas is supplied to the heating flow path of the rotary kiln, dust adheres and accumulates on the outer surface of the inner cylinder, and this deposit is deposited. And / or deposits (hereinafter referred to as "adhesions, etc.") reduce the heat transfer performance of the inner cylinder, and as a result, there is a problem that the thermal efficiency of the rotary kiln is reduced.

この問題に対し、特許文献１では、外筒に空気噴出ノズルを設置し、内筒の外表面のダストの付着量が一定量を超えたときに、空気噴出ノズルから内筒の外表面へ向けて圧縮空気を噴出するようにしている。 In response to this problem, in Patent Document 1, an air ejection nozzle is installed on the outer cylinder, and when the amount of dust adhering to the outer surface of the inner cylinder exceeds a certain amount, the air ejection nozzle is directed toward the outer surface of the inner cylinder. It is designed to eject compressed air.

特開２００８−１９６７３５号公報Japanese Unexamined Patent Publication No. 2008-196735

しかし、上記特許文献１の構成によれば、空気噴出ノズルは複数箇所に設けられているものの、内筒の外表面にスポット的に圧縮空気が作用することになり、内筒の外表面の全体に亘る付着物等の剥離効果が期待できない。また、内筒の外表面の広い範囲に圧縮空気を作用させるためには、空気噴射ノズルの数や空気圧縮機の容量を増加せねばならず、空気噴出ノズルや空気圧縮機の容量増加分に伴う設備費用が嵩むので経済的ではない。 However, according to the configuration of Patent Document 1, although the air ejection nozzles are provided at a plurality of locations, the compressed air acts on the outer surface of the inner cylinder in a spot manner, and the entire outer surface of the inner cylinder is formed. The peeling effect of deposits and the like cannot be expected. In addition, in order for compressed air to act on a wide range of the outer surface of the inner cylinder, the number of air injection nozzles and the capacity of the air compressor must be increased, and the capacity of the air ejection nozzles and the air compressor is increased. It is not economical because the equipment cost involved is high.

本発明は以上の事情に鑑みてされたものであり、その目的は、既存の外熱式ロータリーキルンの設備を利用して、内筒の外表面へのダストの付着を抑制し、また、内筒の外表面の付着物等を除去することにある。 The present invention has been made in view of the above circumstances, and an object of the present invention is to suppress the adhesion of dust to the outer surface of the inner cylinder by utilizing the existing external heating type rotary kiln equipment, and also to suppress the adhesion of dust to the outer surface of the inner cylinder. The purpose is to remove deposits on the outer surface of the.

本願の発明者らは、内筒の外表面にダストが付着する現象（堆積も含む）は、外筒と内筒との間に導入される高温ガスのダスト濃度と流量とに関連していると考えている。この観点に基づけば、内筒の外表面に付着しているダストを吹き飛ばすための方策として、高温ガスの流量を増やす方法と、高温ガスのダスト濃度を下げる方法とが考えられる。 The inventors of the present application have stated that the phenomenon of dust adhering to the outer surface of the inner cylinder (including deposition) is related to the dust concentration and flow rate of the high-temperature gas introduced between the outer cylinder and the inner cylinder. I believe. Based on this viewpoint, as a measure for blowing off the dust adhering to the outer surface of the inner cylinder, a method of increasing the flow rate of the high temperature gas and a method of decreasing the dust concentration of the high temperature gas can be considered.

高温ガスの流量を増やす方法では、ダストが付着したときよりも多い流量の高温ガスを内筒と外筒の間に流せばよい。しかし、高温ガスの流量が増大すると、系の熱量バランスが乱れ、ロータリーキルンの運転が不安定となる恐れがある。また、高温ガスの流量を増大させるために、ファンが大型化するため、経済的ではない。 In the method of increasing the flow rate of the high-temperature gas, a high-temperature gas having a higher flow rate than when dust is attached may be flowed between the inner cylinder and the outer cylinder. However, if the flow rate of the high-temperature gas increases, the calorific value balance of the system may be disturbed and the operation of the rotary kiln may become unstable. In addition, it is not economical because the fan becomes large in order to increase the flow rate of the high temperature gas.

高温ガスのダスト濃度を下げる方法では、ダストが付着したときよりもダスト濃度の低い高温ガスを内筒と外筒の間に流せばよい。しかし、高温ガスのダスト濃度の低減だけでは、付着物等の高い剥離効果は見込めない。 In the method of lowering the dust concentration of the high-temperature gas, a high-temperature gas having a lower dust concentration than when the dust adheres may be flowed between the inner cylinder and the outer cylinder. However, a high peeling effect of deposits and the like cannot be expected only by reducing the dust concentration of the high temperature gas.

そこで、本発明の一態様に係るロータリーキルンの運転方法は、
同心状に配置された内筒と外筒とを有し、前記内筒と前記外筒の間に形成された加熱流路を流れる高温ガスによって前記内筒内を通過する被処理物が間接的に加熱されて熱分解ガスと熱分解残渣とに熱分解し、前記熱分解ガスを燃焼炉で燃焼して生じたガスが前記高温ガスとして前記加熱流路に供給される、ロータリーキルンの運転方法であって、
前記ロータリーキルンの連続する定常運転の間に前記内筒の外表面の付着物及び／又は堆積物を除去するためのリフレッシュ運転を行い、
前記リフレッシュ運転において、前記加熱流路のガス出口の前記高温ガスのノルマル流量を前記定常運転時の値又はその値から所定の範囲内に維持しながら、前記定常運転時に前記加熱流路を流れる前記高温ガスよりも温度が高く且つダスト濃度が低いフレッシュガスを、所定のリフレッシュ時間に亘って前記加熱流路へ流すことを特徴としている。 Therefore, the method of operating the rotary kiln according to one aspect of the present invention is described.
An object to be processed that has an inner cylinder and an outer cylinder arranged concentrically and passes through the inner cylinder by a high-temperature gas flowing through a heating flow path formed between the inner cylinder and the outer cylinder is indirectly. In the operation method of the rotary kiln, which is heated to and thermally decomposed into a pyrolysis gas and a pyrolysis residue, and the gas generated by burning the pyrolysis gas in a combustion furnace is supplied to the heating flow path as the high temperature gas. There,
During the continuous steady operation of the rotary kiln, a refresh operation is performed to remove deposits and / or deposits on the outer surface of the inner cylinder.
In the refresh operation, the normal flow rate of the high temperature gas at the gas outlet of the heating flow path is maintained within a predetermined range from the value at the time of the steady operation or the value, and flows through the heating flow path during the steady operation. It is characterized in that a fresh gas having a higher temperature and a lower dust concentration than the high-temperature gas is flowed into the heating flow path for a predetermined refresh time.

上記ロータリーキルンの運転方法の前記リフレッシュ運転において、前記加熱流路のガス出口の前記高温ガスのノルマル流量、及び、前記加熱流路のガス入口の前記高温ガスの温度を前記定常運転時の値又はその値から所定の範囲内に維持しながら、前記ロータリーキルンへの前記被処理物の供給を中断し、前記被処理物の供給を中断してから前記被処理物の前記ロータリーキルンにおける滞留時間が経過し、更に、所定のリフレッシュ時間が経過してから、前記被処理物の供給を再開してよい。 In the refresh operation of the operation method of the rotary kiln, the normal flow rate of the high temperature gas at the gas outlet of the heating flow path and the temperature of the high temperature gas at the gas inlet of the heating flow path are set to the values at the time of the steady operation or the values thereof. While maintaining within a predetermined range from the value, the supply of the object to be processed to the rotary kiln is interrupted, and the residence time of the object to be processed in the rotary kiln elapses after the supply of the object to be processed is interrupted. Further, the supply of the object to be processed may be restarted after the predetermined refresh time has elapsed.

また、本発明の別の一態様に係るロータリーキルンは、
同心状に配置された内筒と外筒とを有し、前記内筒と前記外筒の間に高温ガスが流れる加熱流路が形成された炉本体と、
前記内筒内へ被処理物を供給する供給装置と、
前記炉本体で前記被処理物の熱分解により生じた熱分解ガスを、燃焼炉へ燃料として送る熱分解ガスラインと、
前記燃焼炉で生じた燃焼ガスを前記高温ガスとして前記加熱流路のガス入口へ送る高温ガス供給ラインと、
前記加熱流路のガス入口へ供給される前記高温ガスの温度を検出する入口温度センサと、
前記加熱流路のガス入口へ供給される前記高温ガスの温度を調整する温度調整装置と、
前記加熱流路のガス出口から排出される前記高温ガスの温度を検出する出口温度センサと、
前記加熱流路のガス出口から排出される前記高温ガスの流量を検出する流量センサと、
前記加熱流路のガス出口から前記高温ガスを強制排気するファンと、
前記供給装置、前記温度調整装置、及び前記ファンの動作を制御するコントローラとを備え、
前記コントローラは、連続する定常運転の間に前記内筒の外表面の付着物及び／又は堆積物を除去するためのリフレッシュ運転を行い、前記リフレッシュ運転において、前記加熱流路のガス出口の前記高温ガスのノルマル流量が前記定常運転時の値又はその値から所定の範囲内を維持するように前記出口温度センサ及び前記流量センサの検出値に基づいて前記ファンを動作させ、前記加熱流路のガス入口の前記高温ガスの温度が前記定常運転時の値を維持するように前記入口温度センサの検出値に基づいて前記温度調整装置を動作させ、前記炉本体への前記被処理物の供給を中断し、前記被処理物の供給を中断してから前記被処理物の前記炉本体における滞留時間が経過し、更に、所定のリフレッシュ時間が経過してから、前記被処理物の供給を再開するように前記供給装置を動作させるように構成されていることを特徴としている。 Further, the rotary kiln according to another aspect of the present invention is:
A furnace body having an inner cylinder and an outer cylinder arranged concentrically, and a heating flow path in which a high-temperature gas flows is formed between the inner cylinder and the outer cylinder.
A supply device that supplies the object to be processed into the inner cylinder, and
A pyrolysis gas line that sends the pyrolysis gas generated by the thermal decomposition of the object to be processed in the furnace body to the combustion furnace as fuel.
A high-temperature gas supply line that sends the combustion gas generated in the combustion furnace as the high-temperature gas to the gas inlet of the heating flow path, and
An inlet temperature sensor that detects the temperature of the high-temperature gas supplied to the gas inlet of the heating flow path, and an inlet temperature sensor.
A temperature control device that adjusts the temperature of the high-temperature gas supplied to the gas inlet of the heating flow path, and
An outlet temperature sensor that detects the temperature of the high-temperature gas discharged from the gas outlet of the heating flow path, and an outlet temperature sensor.
A flow rate sensor that detects the flow rate of the high-temperature gas discharged from the gas outlet of the heating flow path, and
A fan that forcibly exhausts the high-temperature gas from the gas outlet of the heating flow path,
The supply device, the temperature control device, and a controller for controlling the operation of the fan are provided.
The controller performs a refresh operation for removing deposits and / or deposits on the outer surface of the inner cylinder during continuous steady operation, and in the refresh operation, the high temperature of the gas outlet of the heating flow path. The fan is operated based on the outlet temperature sensor and the detected value of the flow rate sensor so that the normal flow rate of the gas is maintained within a predetermined range from the value during steady operation or the value thereof, and the gas in the heating flow path is operated. The temperature adjusting device is operated based on the detected value of the inlet temperature sensor so that the temperature of the high temperature gas at the inlet maintains the value during the steady operation, and the supply of the object to be processed to the furnace body is interrupted. Then, after the supply of the object to be processed is interrupted, the residence time of the object to be processed in the furnace body elapses, and after a predetermined refresh time elapses, the supply of the object to be processed is restarted. It is characterized in that it is configured to operate the supply device.

上記のロータリーキルン及びロータリーキルンの運転方法によれば、リフレッシュ運転時の加熱流路には、定常運転時よりも高い温度で、且つ、ダスト濃度が低い高温ガス（即ち、フレッシュガス）が流れる。リフレッシュ運転時と定常運転時とで加熱流路から排出される高温ガスのノルマル流量は同じであるが、リフレッシュ運転時では定常運転時と比較して温度が高いため実流量は多い。従って、リフレッシュ運転時には、定常運転時と比較して、実流量が多く且つダスト濃度が低い高温ガス（即ち、フレッシュガス）が加熱流路を流れることとなる。この高温ガスの流れによって、定常運転時に内筒の外表面に付着したダストは吹き飛ばされ、また、内筒の外表面に付着しようとしているダストは高温ガスの流れに乗って加熱流路から排出される。このように、上記のロータリーキルン及びロータリーキルンの運転方法によれば、既存の外熱式ロータリーキルンの設備を利用して、内筒の外表面へのダストの付着を抑制し、また、内筒の外表面の付着物等を除去することができる。 According to the above-mentioned rotary kiln and the operation method of the rotary kiln, a high-temperature gas (that is, fresh gas) having a temperature higher than that in the steady operation and a low dust concentration flows in the heating flow path during the refresh operation. The normal flow rate of the high-temperature gas discharged from the heating flow path is the same during the refresh operation and the steady operation, but the actual flow rate is large during the refresh operation because the temperature is higher than that during the steady operation. Therefore, during the refresh operation, a high-temperature gas (that is, fresh gas) having a large actual flow rate and a low dust concentration flows through the heating flow path as compared with the steady operation. Due to this flow of high-temperature gas, dust adhering to the outer surface of the inner cylinder during steady operation is blown away, and dust that is about to adhere to the outer surface of the inner cylinder is discharged from the heating flow path along with the flow of high-temperature gas. To. As described above, according to the above-mentioned rotary kiln and the operation method of the rotary kiln, the existing external heating type rotary kiln equipment is used to suppress the adhesion of dust to the outer surface of the inner cylinder, and the outer surface of the inner cylinder is suppressed. It is possible to remove the deposits and the like.

本発明によれば、既存の外熱式ロータリーキルンの設備を利用して、内筒の外表面へのダストの付着を抑制し、また、内筒の外表面の付着物等を除去することができる。 According to the present invention, it is possible to suppress the adhesion of dust to the outer surface of the inner cylinder and remove the deposits and the like on the outer surface of the inner cylinder by utilizing the existing equipment of the external heating type rotary kiln. ..

図１は、本発明の一実施形態に係るロータリーキルンの全体的な構成を示す図である。FIG. 1 is a diagram showing an overall configuration of a rotary kiln according to an embodiment of the present invention. 図２は、リフレッシュ運転中の加熱流路のガス入口及びガス出口の高温ガスの温度の変化を表す図表である。FIG. 2 is a chart showing changes in the temperature of the high-temperature gas at the gas inlet and the gas outlet of the heating flow path during the refresh operation.

次に、図面を参照して本発明の実施の形態を説明する。図１は、本発明の一実施形態に係る本発明のロータリーキルン１００の概略構成を示す図である。 Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of a rotary kiln 100 of the present invention according to an embodiment of the present invention.

図１に示すように、本実施形態に係る外熱式のロータリーキルン１００は、外熱式の炉本体１と、ロータリーキルン１００の動作を制御するコントローラ３などとを備えている。ロータリーキルン１００には、発生する熱分解ガス８を燃焼する燃焼炉２が隣設されている。 As shown in FIG. 1, the external heat type rotary kiln 100 according to the present embodiment includes an external heat type furnace main body 1 and a controller 3 for controlling the operation of the rotary kiln 100. A combustion furnace 2 for burning the generated pyrolysis gas 8 is adjacent to the rotary kiln 100.

ロータリーキルン１００の炉本体１は、長手方向の一端を入口１ａとし且つ他端を出口１ｂとし、入口１ａ側より出口１ｂ側へ或る角度、たとえば、約３度下方へ傾斜させた状態で横向きに配置されている。 The furnace body 1 of the rotary kiln 100 has an inlet 1a at one end in the longitudinal direction and an outlet 1b at the other end, and is laterally inclined at an angle from the inlet 1a side to the outlet 1b side, for example, about 3 degrees downward. Have been placed.

炉本体１の入口１ａには、投入ホッパ４１を備えた供給装置４が設けられている。供給装置４は、例えば、スクリューフィーダであってよい。 A supply device 4 provided with a charging hopper 41 is provided at the inlet 1a of the furnace body 1. The feeder 4 may be, for example, a screw feeder.

また、炉本体１の出口１ｂには、熱分解ガス８と熱分解残渣９を分離して取り出すための分離室７が設けられている。分離室７の頂部には、熱分解ガス出口２２が設けられており、この熱分解ガス出口２２は熱分解ガスライン２４を通じて燃焼炉２と接続されている。また、分離室７の底部には、熱分解残渣回収口２３が設けられている。 Further, a separation chamber 7 for separating and taking out the pyrolysis gas 8 and the pyrolysis residue 9 is provided at the outlet 1b of the furnace body 1. A pyrolysis gas outlet 22 is provided at the top of the separation chamber 7, and the pyrolysis gas outlet 22 is connected to the combustion furnace 2 through a pyrolysis gas line 24. Further, a thermal decomposition residue recovery port 23 is provided at the bottom of the separation chamber 7.

炉本体１は、内筒１８と、その外側に同心状に配置された外筒２１とからなる、二重筒構造を有する。本実施形態においては、内筒１８は一本であるが、内筒１８は複数であってもよい。内筒１８と外筒２１は、図示しない駆動機構により一体的に回転駆動される。 The furnace body 1 has a double cylinder structure including an inner cylinder 18 and an outer cylinder 21 arranged concentrically on the outer side thereof. In the present embodiment, the number of inner cylinders 18 is one, but the number of inner cylinders 18 may be plural. The inner cylinder 18 and the outer cylinder 21 are integrally rotationally driven by a drive mechanism (not shown).

内筒１８は、入口１ａ側に供給管１９が、出口１ｂ側に排出管２０が、それぞれ接続されている。供給装置４は、被処理物６の出口が供給管１９の内側に挿入されるように配置されており、供給装置４によって投入ホッパ４１内の被処理物６が内筒１８内へ供給される。 The inner cylinder 18 has a supply pipe 19 connected to the inlet 1a side and a discharge pipe 20 connected to the outlet 1b side. The supply device 4 is arranged so that the outlet of the object to be processed 6 is inserted inside the supply pipe 19, and the object to be processed 6 in the charging hopper 41 is supplied into the inner cylinder 18 by the supply device 4. ..

内筒１８と外筒２１との間には、高温ガスが通過する加熱流路１０が形成されている。この加熱流路１０を通過する高温ガスによって、内筒１８を通過する被処理物６（例えば、廃棄物）が間接的に加熱される。 A heating flow path 10 through which high-temperature gas passes is formed between the inner cylinder 18 and the outer cylinder 21. The high-temperature gas passing through the heating flow path 10 indirectly heats the object to be processed 6 (for example, waste) passing through the inner cylinder 18.

加熱流路１０のガス入口１０ａは炉本体１の出口１ｂ側部分に設けられ、加熱流路１０のガス出口１０ｂは炉本体１の入口１ａ側部分に設けられている。加熱流路１０のガス入口１０ａは、高温ガス供給ライン１３を介して、燃焼炉２と接続されている。高温ガス供給ライン１３には、燃焼炉２から加熱流路１０のガス入口１０ａへ送られる高温ガスの流量を調節する流量調整弁１６が設けられている。また、高温ガス供給ライン１３においてガス入口１０ａの近傍には、加熱流路１０のガス入口１０ａへ送られる高温ガスの温度を検出する入口温度センサ１７が設けられている。 The gas inlet 10a of the heating flow path 10 is provided on the outlet 1b side portion of the furnace body 1, and the gas outlet 10b of the heating flow path 10 is provided on the inlet 1a side portion of the furnace body 1. The gas inlet 10a of the heating flow path 10 is connected to the combustion furnace 2 via the high temperature gas supply line 13. The high temperature gas supply line 13 is provided with a flow rate adjusting valve 16 for adjusting the flow rate of the high temperature gas sent from the combustion furnace 2 to the gas inlet 10a of the heating flow path 10. Further, in the vicinity of the gas inlet 10a in the high temperature gas supply line 13, an inlet temperature sensor 17 for detecting the temperature of the high temperature gas sent to the gas inlet 10a of the heating flow path 10 is provided.

一方、加熱流路１０のガス出口１０ｂには、高温ガス循環ファン３８を備えた高温ガス循環ライン３７の上流側端部が接続されている。高温ガス循環ファン３８の設計風量は、定常運転時の風量（定常風量）に設計余裕を加えた値である。設計余裕は、定常風量の１０〜２０％であってよい。 On the other hand, the upstream end of the high temperature gas circulation line 37 provided with the high temperature gas circulation fan 38 is connected to the gas outlet 10b of the heating flow path 10. The design air volume of the high-temperature gas circulation fan 38 is a value obtained by adding a design margin to the air volume during steady operation (steady air volume). The design margin may be 10 to 20% of the steady air volume.

高温ガス循環ライン３７の下流側端部は、燃焼炉２と接続されている。高温ガス循環ライン３７には、加熱流路１０のガス出口１０ｂから排出された高温ガスの温度を検出する出口温度センサ３２が設けられている。また、高温ガス循環ライン３７において燃焼炉２の近傍には、燃焼炉２へ戻される高温ガスの流量を検出する流量センサ３９が設けられている。 The downstream end of the high temperature gas circulation line 37 is connected to the combustion furnace 2. The high temperature gas circulation line 37 is provided with an outlet temperature sensor 32 that detects the temperature of the high temperature gas discharged from the gas outlet 10b of the heating flow path 10. Further, in the high temperature gas circulation line 37, a flow rate sensor 39 for detecting the flow rate of the high temperature gas returned to the combustion furnace 2 is provided in the vicinity of the combustion furnace 2.

更に、高温ガス循環ライン３７の高温ガス循環ファン３８よりも下流側には、高温ガス戻しライン３３の上流側端部が接続されており、この高温ガス戻しライン３３の下流側端部は高温ガス供給ライン１３と接続されている。この高温ガス戻しライン３３を通じて、加熱流路１０のガス出口１０ｂから排出された高温ガスをガス入口１０ａへ戻すことができる。高温ガス戻しライン３３には、加熱流路１０のガス出口１０ｂからガス入口１０ａへ戻される高温ガスの流量と、加熱流路１０のガス出口１０ｂから燃焼炉２へ還流する高温ガスの流量とを調整する流量調整弁３４が設けられている。 Further, the upstream end of the high temperature gas return line 33 is connected to the downstream side of the high temperature gas circulation line 37 with respect to the high temperature gas circulation fan 38, and the downstream end of the high temperature gas return line 33 is a high temperature gas. It is connected to the supply line 13. Through the high temperature gas return line 33, the high temperature gas discharged from the gas outlet 10b of the heating flow path 10 can be returned to the gas inlet 10a. The high temperature gas return line 33 has a flow rate of high temperature gas returned from the gas outlet 10b of the heating flow path 10 to the gas inlet 10a and a flow rate of high temperature gas returning from the gas outlet 10b of the heating flow path 10 to the combustion furnace 2. A flow rate adjusting valve 34 for adjusting is provided.

コントローラ３は、入口温度センサ１７、出口温度センサ３２、及び流量センサ３９などの検出値に基づいて、供給装置４、高温ガス循環ファン３８、流量調整弁１６、及び流量調整弁３４などの動作を制御する。 The controller 3 operates the supply device 4, the high temperature gas circulation fan 38, the flow rate adjusting valve 16, the flow rate adjusting valve 34, and the like based on the detected values of the inlet temperature sensor 17, the outlet temperature sensor 32, the flow rate sensor 39, and the like. Control.

コントローラ３は、いわゆるコンピュータであって、プロセッサと、メモリ及び通信インターフェイスなどとを備えている（いずれも図示略）。メモリは、各種のＲＡＭ、ＲＯＭ、フラッシュメモリ、ハードディスクなどによって実現されてよい。メモリには、プロセッサによって実行される、ＯＳ、各種の制御プログラム、並びにプロセッサによって読み出される各種データを格納する。通信インターフェイスは、プロセッサによって制御されることによって、無線又は有線の通信手段を利用して、供給装置４、高温ガス循環ファン３８、流量調整弁１６、及び流量調整弁３４などとデータを送受信し、また、入口温度センサ１７、出口温度センサ３２、及び流量センサ３９から検出信号を受信する。 The controller 3 is a so-called computer, and includes a processor, a memory, a communication interface, and the like (both are not shown). The memory may be realized by various RAMs, ROMs, flash memories, hard disks, and the like. The memory stores the OS executed by the processor, various control programs, and various data read by the processor. The communication interface is controlled by a processor to transmit and receive data to and from the supply device 4, the high temperature gas circulation fan 38, the flow rate adjusting valve 16, the flow rate adjusting valve 34, and the like by using wireless or wired communication means. Further, the detection signal is received from the inlet temperature sensor 17, the outlet temperature sensor 32, and the flow rate sensor 39.

プロセッサは、メモリに記憶されている各種のプログラムを実行することによって、各種の処理を実行する。換言すれば、コントローラ３における処理は、各ハードウェアおよびプロセッサにより実行されるソフトウェアによって実現される。このようなソフトウェアは、メモリ又は他の記憶媒体に予め記憶されている。 The processor executes various processes by executing various programs stored in the memory. In other words, the processing in the controller 3 is realized by the software executed by each hardware and processor. Such software is pre-stored in memory or other storage medium.

〔ロータリーキルン１００の定常運転時の動作〕
ここで、上記構成のロータリーキルン１００の定常運転時の動作を説明する。 [Operation of rotary kiln 100 during steady operation]
Here, the operation of the rotary kiln 100 having the above configuration during steady operation will be described.

加熱流路１０のガス入口１０ａには、燃焼炉２で発生した燃焼ガスが高温ガス供給ライン１３を通じて供給され、この高温ガスが加熱流路１０を流れている。加熱流路１０のガス入口１０ａに供給される高温ガスが所定の入口温度（例えば、５５０℃）となるように、コントローラ３は、入口温度センサ１７の検出値に基づいて、流量調整弁１６，３４の動作を制御する。ここで、流量調整弁１６，３４は、加熱流路１０のガス入口１０ａへ供給される高温ガスの温度を調整する温度調整装置として機能する。 The combustion gas generated in the combustion furnace 2 is supplied to the gas inlet 10a of the heating flow path 10 through the high temperature gas supply line 13, and this high temperature gas flows through the heating flow path 10. The controller 3 determines the flow rate adjusting valve 16, based on the detection value of the inlet temperature sensor 17, so that the high temperature gas supplied to the gas inlet 10a of the heating flow path 10 has a predetermined inlet temperature (for example, 550 ° C.). Control the operation of 34. Here, the flow rate adjusting valves 16 and 34 function as a temperature adjusting device for adjusting the temperature of the high temperature gas supplied to the gas inlet 10a of the heating flow path 10.

加熱流路１０のガス出口１０ｂから排出された高温ガスは、高温ガス循環ファン３８の稼働により、一部分が高温ガス循環ライン３７を通じて燃焼炉２へ戻され、残部が高温ガス循環ライン３７、高温ガス戻しライン３３、及び高温ガス供給ライン１３を通じて、加熱流路１０のガス入口１０ａへ戻される。加熱流路１０のガス出口１０ｂから排出される高温ガスのノルマル流量が所定の値となるように、コントローラ３は、出口温度センサ３２の検出値に基づいて、高温ガス循環ファン３８の動作を制御する。 A part of the high temperature gas discharged from the gas outlet 10b of the heating flow path 10 is returned to the combustion furnace 2 through the high temperature gas circulation line 37 by the operation of the high temperature gas circulation fan 38, and the rest is returned to the combustion furnace 2 through the high temperature gas circulation line 37 and the high temperature gas. It is returned to the gas inlet 10a of the heating flow path 10 through the return line 33 and the high temperature gas supply line 13. The controller 3 controls the operation of the high temperature gas circulation fan 38 based on the detected value of the outlet temperature sensor 32 so that the normal flow rate of the high temperature gas discharged from the gas outlet 10b of the heating flow path 10 becomes a predetermined value. To do.

内筒１８内には、供給装置４の動作により、投入ホッパ４１内の被処理物６が供給されている。被処理物６は、回転する内筒１８内を分離室７へ向けて移動するうちに、加熱流路１０を通過する高温ガスによって間接的に加熱されて、熱分解ガス８と熱分解残渣９に熱分解する。 The object 6 in the charging hopper 41 is supplied into the inner cylinder 18 by the operation of the supply device 4. The object 6 to be processed is indirectly heated by the high-temperature gas passing through the heating flow path 10 while moving in the rotating inner cylinder 18 toward the separation chamber 7, and the pyrolysis gas 8 and the pyrolysis residue 9 are generated. Pyrolyzes into.

分離室７は、被処理物６の熱分解によって生じた熱分解ガス８と熱分解残渣９を、排出管２０を通して一旦受け取り、気体である熱分解ガス８と固体である熱分解残渣９とを分離させる。熱分解ガス８は、分離室７の頂部の熱分解ガス出口２２から、熱分解ガスライン２４を通じて燃焼炉２へ送られ、燃料として利用される。一方、熱分解残渣９は、分離室７の底部の熱分解残渣回収口２３から排出され、回収される。 The separation chamber 7 once receives the pyrolysis gas 8 and the pyrolysis residue 9 generated by the thermal decomposition of the object 6 through the discharge pipe 20, and temporarily receives the pyrolysis gas 8 which is a gas and the pyrolysis residue 9 which is a solid. Separate. The pyrolysis gas 8 is sent from the pyrolysis gas outlet 22 at the top of the separation chamber 7 to the combustion furnace 2 through the pyrolysis gas line 24, and is used as fuel. On the other hand, the pyrolysis residue 9 is discharged from the pyrolysis residue recovery port 23 at the bottom of the separation chamber 7 and recovered.

燃焼炉２は、ロータリーキルン１００から送られてきた熱分解ガス８を燃料として燃焼し、高温ガスを発生させる。燃焼炉２には、助燃バーナ２５と、炉内の温度を検出する温度センサ２６と、温度維持装置２７とが設けられている。温度維持装置２７は、温度センサ２６の検出値に基づいて、炉内が所定の炉内温度に維持されるように、助燃バーナ２５を動作させる。つまり、温度維持装置２７は、炉本体１から送られてくる熱分解ガス８の燃焼だけでは炉内が所定温度に満たないときには、助燃バーナ２５を燃焼させて炉内を所定の炉内温度まで上昇させる。 The combustion furnace 2 burns the pyrolysis gas 8 sent from the rotary kiln 100 as fuel to generate a high temperature gas. The combustion furnace 2 is provided with a combustion assisting burner 25, a temperature sensor 26 for detecting the temperature inside the furnace, and a temperature maintenance device 27. The temperature maintenance device 27 operates the combustion assisting burner 25 so that the inside of the furnace is maintained at a predetermined temperature inside the furnace based on the detected value of the temperature sensor 26. That is, when the temperature inside the furnace does not reach the predetermined temperature only by burning the pyrolysis gas 8 sent from the furnace body 1, the temperature maintaining device 27 burns the combustion assisting burner 25 to bring the inside of the furnace to the predetermined temperature inside the furnace. Raise it.

上記のロータリーキルン１００では、炉本体１の加熱流路１０をダストを伴う燃焼炉２の燃焼ガスが通過することから、内筒１８の外表面にダストが付着（又は、堆積）するおそれがある。そこで、ロータリーキルン１００では、所定間隔（例えば、半月ごと）で、内筒１８の外表面の付着物等を除去するためのリフレッシュ運転を行う。以下、ロータリーキルン１００のリフレッシュ運転時の動作を説明する。 In the above rotary kiln 100, since the combustion gas of the combustion furnace 2 accompanied by dust passes through the heating flow path 10 of the furnace body 1, dust may adhere (or accumulate) on the outer surface of the inner cylinder 18. Therefore, in the rotary kiln 100, a refresh operation is performed at predetermined intervals (for example, every half a month) to remove deposits and the like on the outer surface of the inner cylinder 18. Hereinafter, the operation of the rotary kiln 100 during the refresh operation will be described.

〔ロータリーキルン１００のリフレッシュ運転時の動作〕
図２は、リフレッシュ運転中の加熱流路１０のガス入口１０ａ及びガス出口１０ｂの高温ガスの温度の変化を表す図表である。図２に示すように、コントローラ３は、連続する定常運転の間にリフレッシュ運転を行う。リフレッシュ運転の間隔は予めスケジュールされている。 [Operation during refresh operation of rotary kiln 100]
FIG. 2 is a chart showing changes in the temperature of the high-temperature gas at the gas inlet 10a and the gas outlet 10b of the heating flow path 10 during the refresh operation. As shown in FIG. 2, the controller 3 performs a refresh operation during continuous steady operation. The refresh operation interval is scheduled in advance.

コントローラ３は、定常運転からリフレッシュ運転に切り替えると、供給装置４を停止させて、被処理物６の供給を中断する。 When the controller 3 switches from the steady operation to the refresh operation, the controller 3 stops the supply device 4 and interrupts the supply of the object 6 to be processed.

なお、リフレッシュ運転の間、加熱流路１０のガス入口１０ａの高温ガスの温度は、定常運転時の値に維持される。つまり、コントローラ３は、入口温度センサ１７の検出値に基づいて、定常運転時と同じ入口温度となるように、温度調整装置（流量調整弁１６，３４）を動作させる。 During the refresh operation, the temperature of the high temperature gas at the gas inlet 10a of the heating flow path 10 is maintained at the value at the time of steady operation. That is, the controller 3 operates the temperature adjusting devices (flow rate adjusting valves 16 and 34) so that the inlet temperature becomes the same as in the steady operation based on the detected value of the inlet temperature sensor 17.

また、リフレッシュ運転の間、加熱流路１０のガス出口１０ｂの高温ガスのノルマル流量は、定常運転時の値に維持される。つまり、コントローラ３は、出口温度センサ３２及び流量センサ３９の検出値に基づいて、加熱流路１０のガス出口１０ｂのノルマル流量が定常運転時と同じノルマル流量となるように、高温ガス循環ファン３８を動作させる。このように、定常運転とリフレッシュ運転とを通じて、系のノルマル流量の変動が抑えられることで、系のガス流量が安定し、その結果、安定した運転を維持することができる。但し、リフレッシュ運転の間の加熱流路１０のガス出口１０ｂのノルマル流量は、厳密に定常運転時と同じノルマル流量に維持される必要はなく、定常運転時の値から高温ガス循環ファン３８の風量が設計風量以下となる所定の範囲内での変動が許容されてもよい。 Further, during the refresh operation, the normal flow rate of the high temperature gas at the gas outlet 10b of the heating flow path 10 is maintained at the value at the time of steady operation. That is, the controller 3 has the high temperature gas circulation fan 38 so that the normal flow rate of the gas outlet 10b of the heating flow path 10 becomes the same normal flow rate as in the steady operation based on the detected values of the outlet temperature sensor 32 and the flow rate sensor 39. To operate. In this way, by suppressing fluctuations in the normal flow rate of the system through the steady operation and the refresh operation, the gas flow rate of the system is stabilized, and as a result, stable operation can be maintained. However, the normal flow rate of the gas outlet 10b of the heating flow path 10 during the refresh operation does not have to be maintained at exactly the same normal flow rate as during the steady operation, and the air volume of the high temperature gas circulation fan 38 is based on the value during the steady operation. May be allowed to fluctuate within a predetermined range where is less than or equal to the design air flow rate.

リフレッシュ運転の間、被処理物６の供給は中断しているが炉本体１での熱分解処理は継続している。そのため、被処理物６の供給を中断する前に最後に炉本体１に供給された被処理物６は、被処理物６の供給が中断してから被処理物６の既知の炉本体１における滞留時間Ｔ1が経過したときに熱分解ガス出口２２又は熱分解残渣回収口２３から排出される。従って、被処理物６の供給を中断してから滞留時間Ｔ1が経過したあとは、炉本体１内がパージされており、内筒１８内には被処理物６が残っていない状態となっている。 During the refresh operation, the supply of the object to be processed 6 is interrupted, but the thermal decomposition treatment in the furnace body 1 continues. Therefore, the object to be processed 6 finally supplied to the furnace body 1 before the supply of the object to be processed 6 is interrupted is in the known furnace body 1 of the object to be processed 6 after the supply of the object to be processed 6 is interrupted. When the residence time T1 elapses, it is discharged from the pyrolysis gas outlet 22 or the pyrolysis residue recovery port 23. Therefore, after the residence time T1 elapses after the supply of the object 6 to be processed is interrupted, the inside of the furnace body 1 is purged, and the object 6 to be processed does not remain in the inner cylinder 18. There is.

そして、コントローラ３は、被処理物６の供給を中断してから滞留時間Ｔ1が経過し、更に、所定のリフレッシュ時間Ｔ2が経過してから、リフレッシュ運転を終了して被処理物６の供給を再開する。リフレッシュ時間Ｔ2は、１時間以上３時間以内の時間であってよい。 Then, the controller 3 terminates the refresh operation after the residence time T1 elapses after interrupting the supply of the object 6 to be processed, and further elapses the predetermined refresh time T2, and supplies the object 6 to be processed. resume. The refresh time T2 may be a time of 1 hour or more and 3 hours or less.

上記のリフレッシュ運転において、炉本体１内がパージされたあとは、炉本体１から燃焼炉２へ送られる熱分解ガス８の量が殆どゼロまで減少する。そのため、燃焼炉２では、炉内を所定の炉内温度（例えば、８５０℃）に維持するために、助燃バーナ２５で補助燃料の燃焼が行われる。補助燃料の燃焼で発生する灰や塵などのダストの量は、熱分解ガス８の燃焼で発生するダストの量と比較して、著しく少ない。よって、炉本体１内がパージされたあとリフレッシュ時間Ｔ2が経過するまでの間は、燃焼炉２から加熱流路１０へ供給される高温ガスのダスト濃度は、定常運転時と比較して少ない。 In the above refresh operation, after the inside of the furnace body 1 is purged, the amount of the pyrolysis gas 8 sent from the furnace body 1 to the combustion furnace 2 is reduced to almost zero. Therefore, in the combustion furnace 2, the auxiliary fuel is burned by the auxiliary combustion burner 25 in order to maintain the inside of the furnace at a predetermined internal temperature (for example, 850 ° C.). The amount of dust such as ash and dust generated by the combustion of the auxiliary fuel is significantly smaller than the amount of dust generated by the combustion of the pyrolysis gas 8. Therefore, the dust concentration of the high-temperature gas supplied from the combustion furnace 2 to the heating flow path 10 is smaller than that during steady operation until the refresh time T2 elapses after the inside of the furnace body 1 is purged.

また、リフレッシュ運転時は、炉本体１で処理される被処理物６の量が定常運転時より少ない又は殆ど無いことから、加熱流路１０を流れる高温ガスの吸熱反応が抑えられ、その結果、加熱流路１０を流れる高温ガスの温度が定常運転時と比較して高い。 Further, during the refresh operation, the amount of the object to be processed 6 processed by the furnace body 1 is less or almost the same as that during the steady operation, so that the endothermic reaction of the high temperature gas flowing through the heating flow path 10 is suppressed, and as a result, The temperature of the high temperature gas flowing through the heating flow path 10 is higher than that during steady operation.

つまり、リフレッシュ運転時（とりわけ、炉本体１内がパージされたあとリフレッシュ時間Ｔ2が経過するまでの間）の加熱流路１０には、定常運転時よりも高い温度且つダスト濃度の低い高温ガスが流れる。そのため、加熱流路１０のガス出口１０ｂの高温ガスのノルマル流量は定常運転時とリフレッシュ運転時とで同じであるが、加熱流路１０を流れる高温ガスの実流量はリフレッシュ運転時の方が多い。従って、リフレッシュ運転時の加熱流路１０には、定常運転時よりも実流量が多く且つダスト濃度が低い高温ガス（以下、「フレッシュガス」と称する場合がある）が流れる。この高温ガスの流れによって、定常運転時に内筒１８の外表面に付着したダストは吹き飛ばされる。なお、吹き飛ばされたダストを含む、内筒１８の外表面に付着しようとしているダストは、高温ガスに同伴してガス出口１０ｂから排出される。このようにして、リフレッシュ運転では、内筒１８の外表面に付着したダストを取り除き、また、内筒１８の外表面に付着しようとしているダストを加熱流路１０から排出することができる。 That is, in the heating flow path 10 during the refresh operation (particularly, after the inside of the furnace body 1 is purged until the refresh time T2 elapses), a high temperature gas having a higher temperature and a lower dust concentration than during the steady operation It flows. Therefore, the normal flow rate of the high temperature gas at the gas outlet 10b of the heating flow path 10 is the same during the steady operation and the refresh operation, but the actual flow rate of the high temperature gas flowing through the heating flow path 10 is larger during the refresh operation. .. Therefore, a high-temperature gas (hereinafter, may be referred to as "fresh gas") having a larger actual flow rate and a lower dust concentration flows through the heating flow path 10 during the refresh operation. Due to this flow of high-temperature gas, dust adhering to the outer surface of the inner cylinder 18 during steady operation is blown away. The dust that is about to adhere to the outer surface of the inner cylinder 18, including the dust that has been blown off, is discharged from the gas outlet 10b along with the high-temperature gas. In this way, in the refresh operation, the dust adhering to the outer surface of the inner cylinder 18 can be removed, and the dust that is about to adhere to the outer surface of the inner cylinder 18 can be discharged from the heating flow path 10.

以上に説明したように、本実施形態のロータリーキルン１００の運転方法は、ロータリーキルン１００の連続する定常運転の間にリフレッシュ運転を行い、リフレッシュ運転において、加熱流路１０のガス出口１０ｂの高温ガスのノルマル流量、及び、加熱流路１０のガス入口１０ａの高温ガスの温度を定常運転時の値（又はその値から所定の範囲内）に維持しながら、ロータリーキルン１００への被処理物６の供給を中断し、被処理物６の供給を中断してから被処理物６のロータリーキルン１００における滞留時間Ｔ1が経過し、更に、所定のリフレッシュ時間Ｔ2が経過してから、被処理物の供給を再開する（即ち、リフレッシュ運転から定常運転に切り替える）ことを特徴としている。 As described above, in the operation method of the rotary kiln 100 of the present embodiment, the refresh operation is performed during the continuous steady operation of the rotary kiln 100, and in the refresh operation, the normal of the high temperature gas at the gas outlet 10b of the heating flow path 10 is normal. Suspending the supply of the object 6 to the rotary kiln 100 while maintaining the flow rate and the temperature of the high-temperature gas at the gas inlet 10a of the heating flow path 10 at the value during steady operation (or within a predetermined range from that value). Then, after the supply of the object 6 to be processed is interrupted, the residence time T1 of the object 6 to be processed in the rotary kiln 100 elapses, and further, after the predetermined refresh time T2 elapses, the supply of the object to be processed is restarted ( That is, it is characterized by switching from refresh operation to steady operation).

同様に、本実施形態のロータリーキルン１００は、同心状に配置された内筒１８と外筒２１とを有し、内筒１８と外筒２１の間に高温ガスが流れる加熱流路１０が形成された炉本体１と、内筒１８内へ被処理物６を供給する供給装置４と、炉本体１で被処理物６の熱分解により生じた熱分解ガス８を、燃焼炉２へ燃料として送る熱分解ガスライン２４と、燃焼炉２で生じた燃焼ガスを高温ガスとして加熱流路１０のガス入口１０ａへ送る高温ガス供給ライン１３と、加熱流路１０のガス入口１０ａへ供給される高温ガスの温度を検出する入口温度センサ１７と、加熱流路１０のガス入口１０ａへ供給される高温ガスの温度を調整する温度調整装置（流量調整弁１６，３４）と、加熱流路１０のガス出口１０ｂから排出される高温ガスの温度を検出する出口温度センサ３２と、加熱流路１０のガス出口１０ｂから排出される高温ガスの流量を検出する流量センサ３９と、加熱流路１０のガス出口１０ｂから高温ガスを強制排気するファン３８と、供給装置４、温度調整装置（流量調整弁１６，３４）、及びファン３８の動作を制御するコントローラ３とを備えている。 Similarly, the rotary kiln 100 of the present embodiment has an inner cylinder 18 and an outer cylinder 21 arranged concentrically, and a heating flow path 10 through which a high temperature gas flows is formed between the inner cylinder 18 and the outer cylinder 21. The furnace body 1, the supply device 4 that supplies the object to be processed 6 into the inner cylinder 18, and the thermal decomposition gas 8 generated by the thermal decomposition of the object 6 to be processed in the furnace body 1 are sent to the combustion furnace 2 as fuel. The thermal decomposition gas line 24, the high temperature gas supply line 13 that sends the combustion gas generated in the combustion furnace 2 as high temperature gas to the gas inlet 10a of the heating flow path 10, and the high temperature gas supplied to the gas inlet 10a of the heating flow path 10. The inlet temperature sensor 17 for detecting the temperature of the heating flow path 10, the temperature adjusting devices (flow rate adjusting valves 16 and 34) for adjusting the temperature of the high temperature gas supplied to the gas inlet 10a of the heating flow path 10, and the gas outlet of the heating flow path 10. An outlet temperature sensor 32 that detects the temperature of the high temperature gas discharged from the heating flow path 10, a flow rate sensor 39 that detects the flow rate of the high temperature gas discharged from the gas outlet 10b of the heating flow path 10, and a gas outlet 10b of the heating flow path 10. It includes a fan 38 that forcibly exhausts high-temperature gas from the air, a supply device 4, temperature control devices (flow control valves 16, 34), and a controller 3 that controls the operation of the fan 38.

そして、上記ロータリーキルン１００は、コントローラ３が、連続する定常運転の間にリフレッシュ運転を行い、リフレッシュ運転において、加熱流路１０のガス出口１０ｂの高温ガスのノルマル流量が定常運転時の値を維持するように出口温度センサ３２及び流量センサ３９の検出値に基づいてファン３８を動作させ、加熱流路１０のガス入口１０ａの高温ガスの温度が定常運転時の値（又はその値から所定の範囲内）を維持するように入口温度センサ１７及び流量センサ３９の検出値に基づいて温度調整装置（流量調整弁１６，３４）を動作させ、炉本体１への被処理物６の供給を中断し、被処理物６の供給を中断してから被処理物６の炉本体１における滞留時間Ｔ1が経過し、更に、所定のリフレッシュ時間Ｔ2が経過してから、被処理物６の供給を再開するように供給装置４を動作させることを特徴としている。 Then, in the rotary kiln 100, the controller 3 performs a refresh operation during continuous steady operation, and in the refresh operation, the normal flow rate of the high temperature gas at the gas outlet 10b of the heating flow path 10 maintains the value at the time of steady operation. As described above, the fan 38 is operated based on the detected values of the outlet temperature sensor 32 and the flow rate sensor 39, and the temperature of the high temperature gas at the gas inlet 10a of the heating flow path 10 is within the value during steady operation (or within a predetermined range from the value). ) Is operated based on the detected values of the inlet temperature sensor 17 and the flow rate sensor 39, and the supply of the object to be processed 6 to the furnace body 1 is interrupted. After the supply of the object 6 to be processed is interrupted, the residence time T1 of the object 6 to be processed in the furnace body 1 elapses, and further, after the predetermined refresh time T2 elapses, the supply of the object 6 to be processed is restarted. It is characterized in that the supply device 4 is operated.

上記ロータリーキルン１００及びその運転方法によれば、リフレッシュ運転時の加熱流路１０には、定常運転時よりも高い温度で、且つ、ダスト濃度が低い高温ガス（即ち、フレッシュガス）が流れる。リフレッシュ運転時と定常運転時とで加熱流路１０から排出される高温ガスのノルマル流量は同じである（又は微増する）が、リフレッシュ運転時では定常運転時と比較して温度が高いため実流量は多い。従って、リフレッシュ運転時には、定常運転時と比較して、実流量が多く且つダスト濃度が低い高温ガス（即ち、フレッシュガス）が加熱流路１０を流れることとなる。この高温ガスの流れによって、定常運転時に内筒１８の外表面に付着したダストは吹き飛ばされ、また、内筒１８の外表面に付着しようとしているダストは高温ガスの流れに乗って加熱流路１０から排出される。このように、上記のロータリーキルン１００及びロータリーキルン１００の運転方法によれば、既存の外熱式ロータリーキルンの設備を利用して、内筒１８の外表面へのダストの付着を抑制し、また、内筒１８の外表面の付着物等を除去することができる。 According to the rotary kiln 100 and its operation method, a high-temperature gas (that is, fresh gas) having a temperature higher than that in the steady operation and a low dust concentration flows in the heating flow path 10 during the refresh operation. The normal flow rate of the high-temperature gas discharged from the heating flow path 10 is the same (or slightly increases) between the refresh operation and the steady operation, but the actual flow rate during the refresh operation is higher than that during the steady operation. There are many. Therefore, during the refresh operation, a high-temperature gas (that is, fresh gas) having a large actual flow rate and a low dust concentration flows through the heating flow path 10 as compared with the steady operation. Due to this flow of high-temperature gas, dust adhering to the outer surface of the inner cylinder 18 during steady operation is blown away, and dust that is about to adhere to the outer surface of the inner cylinder 18 rides on the flow of high-temperature gas and is heated by the heating flow path 10. Is discharged from. As described above, according to the above-mentioned operation method of the rotary kiln 100 and the rotary kiln 100, the existing external heat type rotary kiln equipment is used to suppress the adhesion of dust to the outer surface of the inner cylinder 18, and the inner cylinder It is possible to remove deposits and the like on the outer surface of 18.

以上に本発明の好適な実施の形態を説明したが、本発明の精神を逸脱しない範囲で、上記実施形態の具体的な構造及び／又は機能の詳細を変更したものも本発明に含まれ得る。上記の構成は、例えば、以下のように変更することができる。 Although the preferred embodiment of the present invention has been described above, the present invention may include modified details of the specific structure and / or function of the above embodiment without departing from the spirit of the present invention. .. The above configuration can be changed, for example, as follows.

例えば、上記実施形態に係るロータリーキルン１００では、リフレッシュ運転において被処理物６の供給の中断と再開の指令をコントローラ３が供給装置４に出力するが、オペレータが図示しない操作具を用いて被処理物６の供給の中断と再開の指令を供給装置４に入力してもよい。 For example, in the rotary kiln 100 according to the above embodiment, in the refresh operation, the controller 3 outputs a command for interrupting and restarting the supply of the object to be processed 6 to the supply device 4, but the operator uses an operation tool (not shown) to be the object to be processed. A command for suspending and resuming the supply of 6 may be input to the supply device 4.

また、例えば、上記実施形態に係るロータリーキルン１００では、加熱流路１０のガス入口１０ａの高温ガスの温度が定常運転とリフレッシュ運転とを通じて一定に維持されるが、温度調整装置（流量調整弁１６，３４）によってリフレッシュ運転時の加熱流路１０のガス入口１０ａの高温ガスの温度が定常運転時よりも高くなるように高温ガスの温度が調整されてもよい。この場合、リフレッシュ運転時の加熱流路１０を流れる高温ガス（フレッシュガス）は、定常運転時よりも高温で膨張しているので、定常運転時と比較して実流量が大きく、ダスト濃度も僅かであるが低下している。 Further, for example, in the rotary kiln 100 according to the above embodiment, the temperature of the high temperature gas at the gas inlet 10a of the heating flow path 10 is maintained constant through the steady operation and the refresh operation, but the temperature adjusting device (flow rate adjusting valve 16, 34) may adjust the temperature of the high temperature gas so that the temperature of the high temperature gas at the gas inlet 10a of the heating flow path 10 during the refresh operation is higher than that during the steady operation. In this case, the high-temperature gas (fresh gas) flowing through the heating flow path 10 during the refresh operation expands at a higher temperature than during the steady operation, so that the actual flow rate is larger and the dust concentration is smaller than during the steady operation. However, it is decreasing.

つまり、本発明に係るロータリーキルンの運転方法は上記実施形態に限らず、ロータリーキルンの連続する定常運転の間にリフレッシュ運転を行い、そのリフレッシュ運転において、加熱流路１０のガス出口１０ｂの高温ガスのノルマル流量を定常運転時の値（又はその値から所定の範囲内）に維持しながら、定常運転時に加熱流路１０を流れる高温ガスよりも温度が高く且つダスト濃度が低いフレッシュガスを、所定のリフレッシュ時間に亘って加熱流路１０へ流すものであればよい。 That is, the operation method of the rotary kiln according to the present invention is not limited to the above embodiment, and the refresh operation is performed during the continuous steady operation of the rotary kiln, and in the refresh operation, the normal of the high temperature gas at the gas outlet 10b of the heating flow path 10 is performed. While maintaining the flow rate at the value during steady operation (or within a predetermined range from that value), the fresh gas having a higher temperature and a lower dust concentration than the high temperature gas flowing through the heating flow path 10 during steady operation is refreshed. Anything may be used as long as it flows into the heating flow path 10 over time.

１００ロータリーキルン
１炉本体
２燃焼炉
３コントローラ
４供給装置
６被処理物
７分離室
８熱分解ガス
９熱分解残渣
１０加熱流路
１０ａガス入口
１０ｂガス出口
１３高温ガス供給ライン
１６流量調整弁
１７入口温度センサ
１８内筒
１９供給管
２０排出管
２１外筒
２２熱分解ガス出口
２３熱分解残渣回収口
２４熱分解ガスライン
２５助燃バーナ
２６温度センサ
２７温度維持装置
３２出口温度センサ
３３高温ガス戻しライン
３４流量調整弁
３７高温ガス循環ライン
３８高温ガス循環ファン
３９流量センサ
４１投入ホッパ 100 Rotary kiln 1 Furnace body 2 Combustion furnace 3 Controller 4 Supply device 6 Processed object 7 Separation chamber 8 Pyrolysis gas 9 Pyrolysis residue 10 Heating flow path 10a Gas inlet 10b Gas outlet 13 High temperature gas supply line 16 Flow control valve 17 Inlet temperature Sensor 18 Inner cylinder 19 Supply pipe 20 Discharge pipe 21 Outer cylinder 22 Pyrolysis gas outlet 23 Pyrolysis residue recovery port 24 Pyrolysis gas line 25 Auxiliary burner 26 Temperature sensor 27 Temperature maintenance device 32 Outlet temperature sensor 33 High temperature gas return line 34 Flow rate Control valve 37 High temperature gas circulation line 38 High temperature gas circulation fan 39 Flow sensor 41 Input hopper

Claims

An object to be processed that has an inner cylinder and an outer cylinder arranged concentrically and passes through the inner cylinder by a high-temperature gas flowing through a heating flow path formed between the inner cylinder and the outer cylinder is indirectly. In the operation method of the rotary kiln, which is heated to and thermally decomposed into a pyrolysis gas and a pyrolysis residue, and the gas generated by burning the pyrolysis gas in a combustion furnace is supplied to the heating flow path as the high temperature gas. There,
During the continuous steady operation of the rotary kiln, a refresh operation is performed to remove deposits and / or deposits on the outer surface of the inner cylinder.
In the refresh operation, the normal flow rate of the high temperature gas at the gas outlet of the heating flow path is maintained within a predetermined range from the value at the time of the steady operation or the value, and flows through the heating flow path during the steady operation. A fresh gas having a temperature higher than that of the high-temperature gas and a dust concentration lower than that of the high-temperature gas is flowed through the heating flow path for a predetermined refresh time.
How to drive a rotary kiln.

In the refresh operation
While maintaining the normal flow rate of the high temperature gas at the gas outlet of the heating flow path and the temperature of the high temperature gas at the gas inlet of the heating flow path within the value at the time of steady operation or within a predetermined range from the value. Suspending the supply of the object to be processed to the rotary kiln,
After the supply of the object to be processed is interrupted, the residence time of the object to be processed in the rotary kiln elapses, and after a predetermined refresh time elapses, the supply of the object to be processed is restarted.
The method for operating a rotary kiln according to claim 1.

A furnace body having an inner cylinder and an outer cylinder arranged concentrically, and a heating flow path in which a high-temperature gas flows is formed between the inner cylinder and the outer cylinder.
A supply device that supplies the object to be processed into the inner cylinder, and
A pyrolysis gas line that sends the pyrolysis gas generated by the thermal decomposition of the object to be processed in the furnace body to the combustion furnace as fuel.
A high-temperature gas supply line that sends the combustion gas generated in the combustion furnace as the high-temperature gas to the gas inlet of the heating flow path, and
An inlet temperature sensor that detects the temperature of the high-temperature gas supplied to the gas inlet of the heating flow path, and an inlet temperature sensor.
A temperature control device that adjusts the temperature of the high-temperature gas supplied to the gas inlet of the heating flow path, and
An outlet temperature sensor that detects the temperature of the high-temperature gas discharged from the gas outlet of the heating flow path, and an outlet temperature sensor.
A flow rate sensor that detects the flow rate of the high-temperature gas discharged from the gas outlet of the heating flow path, and
A fan that forcibly exhausts the high-temperature gas from the gas outlet of the heating flow path,
The supply device, the temperature control device, and a controller for controlling the operation of the fan are provided.
The controller performs a refresh operation for removing deposits and / or deposits on the outer surface of the inner cylinder during continuous steady operation, and in the refresh operation, the high temperature of the gas outlet of the heating flow path. The fan is operated based on the outlet temperature sensor and the detected value of the flow rate sensor so that the normal flow rate of the gas is maintained within a predetermined range from the value during steady operation or the value thereof, and the gas in the heating flow path is operated. The temperature adjusting device is operated based on the detected value of the inlet temperature sensor so that the temperature of the high temperature gas at the inlet maintains the value during the steady operation, and the supply of the object to be processed to the furnace body is interrupted. Then, after the supply of the object to be processed is interrupted, the residence time of the object to be processed in the furnace body elapses, and after a predetermined refresh time elapses, the supply of the object to be processed is restarted. To operate the supply device,
Rotary kiln.