JP6021603B2

JP6021603B2 - Incineration equipment

Info

Publication number: JP6021603B2
Application number: JP2012253167A
Authority: JP
Inventors: 匡之馬渡; 幸司滑澤; 嘉正澤本
Original assignee: Mitsubishi Heavy Industries Environmental and Chemical Engineering Co Ltd
Current assignee: Mitsubishi Heavy Industries Environmental and Chemical Engineering Co Ltd
Priority date: 2012-11-19
Filing date: 2012-11-19
Publication date: 2016-11-09
Anticipated expiration: 2032-11-19
Also published as: JP2014102020A

Description

本発明は、焼却設備に関する。 The present invention relates to an incineration facility.

例えば都市ごみなどの被焼却物を焼却処理するためのストーカ式の焼却設備は、被焼却物を一時的に貯留するホッパと、ホッパからシュート部を通じて連続的にフィードテーブル上に供給された被焼却物を所定のストロークで進退移動して焼却炉内に押し出し投入するフィーダと、焼却炉（燃焼ガス流路）の底部側に、金属製の固定火格子とごみの流れ方向に往復運動する可動火格子を交互に配置してなるストーカ（燃焼部）と、ストーカの下方に設けられ、ストーカの各部に一次燃焼空気を供給するための風箱（一次燃焼空気供給部）とを備えて構成されている。 For example, a stoker-type incineration facility for incinerating incineration materials such as municipal waste is a hopper that temporarily stores the incineration material, and incineration that is continuously supplied from the hopper through the chute to the feed table. A feeder that moves the object forward and backward with a predetermined stroke and pushes it into the incinerator, and a movable fire that reciprocates in the direction of dust flow with a metal fixed grate on the bottom side of the incinerator (combustion gas flow path) A stoker (combustion unit) formed by alternately arranging lattices and a wind box (primary combustion air supply unit) provided below the stoker and for supplying primary combustion air to each part of the stoker are configured. Yes.

また、この種の焼却設備においては、焼却炉内のストーカが、フィーダによって押し出されて焼却炉内に落下した被焼却物を受け、被焼却物の水分を蒸発させるとともに一部熱分解するための乾燥ストーカ部と、下方の風箱から供給される一次燃焼空気によって、乾燥ストーカ部で乾燥した被焼却物に着火させ、揮発分および固定炭素分を燃焼させる燃焼ストーカ部と、燃焼ストーカ部で燃焼されずに通過してきた固定炭素分等の未燃分を完全に灰になるまで燃焼させる後燃焼ストーカ部とを備えている。また、被焼却物の搬送方向上流端側から下流端側に順に乾燥ストーカ部、燃焼ストーカ部、後燃焼ストーカ部が配設されるとともに、前記搬送方向下流端側の後燃焼ストーカ部の出口に灰出し口が設けられ、この灰出し口を通じて焼却炉から灰を排出するように構成されている。 Also, in this type of incineration equipment, the stoker in the incinerator receives the incinerated material that has been pushed out by the feeder and dropped into the incinerator, evaporates the moisture of the incinerated material, and partially decomposes it. The primary combustion air supplied from the dry stoker unit and the lower air box ignites the incinerated material dried in the dry stoker unit, and combusts the volatile component and fixed carbon component, and burns in the combustion stoker unit. And a post-combustion stoker section that burns unburned components such as fixed carbon components that have passed through the ash until they completely become ash. In addition, a dry stoker part, a combustion stoker part, and a post-combustion stoker part are arranged in order from the upstream end side to the downstream end side in the conveyance direction of the incineration object, and at the outlet of the post-combustion stoker part on the downstream end side in the conveyance direction. An ash outlet is provided, and the ash is discharged from the incinerator through the ash outlet.

また、焼却炉は、その内部が燃焼ガス流路を形成し、ストーカの上方の燃焼ガス流路が一次燃焼室、一次燃焼室のさらに上方が二次燃焼室とされている。そして、一次燃焼室で生じた燃焼ガスが、二次燃焼空気と混合されて二次燃焼室に送られ、この二次燃焼室で燃焼ガス中の未燃成分を燃焼させる。また、二次燃焼室の後流に熱回収ボイラが接続して配設され、焼却炉の排熱を回収して有効利用できるように構成されている。さらに、熱回収ボイラで熱回収された排ガスは、減温塔、除塵装置等の排ガス処理設備を通過して処理され、煙突から外部に排出される。 Further, the incinerator has a combustion gas flow path formed therein, a combustion gas flow path above the stoker is a primary combustion chamber, and a further upper side of the primary combustion chamber is a secondary combustion chamber. The combustion gas generated in the primary combustion chamber is mixed with the secondary combustion air and sent to the secondary combustion chamber, where unburned components in the combustion gas are combusted in the secondary combustion chamber. In addition, a heat recovery boiler is connected to the downstream of the secondary combustion chamber, and is configured to recover and effectively use the exhaust heat of the incinerator. Furthermore, the exhaust gas heat-recovered by the heat recovery boiler is processed through an exhaust gas treatment facility such as a temperature reducing tower and a dust removal device, and discharged from the chimney.

一方、焼却設備には、焼却炉内の燃焼排ガス中にアンモニアや尿素などの脱硝薬剤を供給する手段（脱硝薬剤供給部）、いわゆる無触媒脱硝システムを備え、脱硝薬剤を供給することで、焼却過程で生成されて燃焼ガス（排ガス）中に含まれるＮＯｘを還元して低減・無害化させるように構成したものがある。また、例えば、脱硝薬剤としてアンモニアを用いた場合、被焼却物を燃焼することで発生するＮＯとＮＨ_３は８００〜１０００℃の温度範囲で好適に還元反応が生じ、また、被焼却物が十分に燃焼した後の領域に脱硝薬剤を供給することが必要になる。このため、一般に、この種の焼却設備では、二次燃焼空気の供給口（供給ノズル、二次燃焼空気供給部）よりも燃焼ガス流通方向下流側に脱硝薬剤を噴霧して供給するように構成されている（例えば、特許文献１参照）。 On the other hand, the incineration facility is equipped with a means for supplying denitration chemicals such as ammonia and urea into the exhaust gas in the incinerator (denitration chemical supply unit), so-called non-catalytic denitration system, and incineration by supplying denitration chemicals Some are configured to reduce and detoxify NOx produced in the process and contained in combustion gas (exhaust gas). In addition, for example, when ammonia is used as a denitration agent, NO and NH ₃ generated by burning the incinerated material suitably undergo a reduction reaction in the temperature range of 800 to 1000 ° C., and the incinerated material is sufficient. Therefore, it is necessary to supply a denitration agent to the area after burning. For this reason, in general, this type of incineration equipment is configured to spray and supply the denitration chemical downstream of the secondary combustion air supply port (supply nozzle, secondary combustion air supply unit) in the combustion gas flow direction. (For example, refer to Patent Document 1).

また、焼却設備には、排ガス処理設備で処理した排ガスの一部を再循環排ガスとして抽出し、この抽出した再循環排ガスを二次燃焼空気の供給口とストーカの間の一次燃焼室に還流させるようにしたものがある。このように再循環排ガスを供給すると、一次燃焼室の雰囲気を弱還元性の雰囲気にすることができ、さらに再循環排ガスの供給によって撹拌混合され、この部分のガス濃度や温度を均一化することができる。これにより、未燃ガス成分や未燃物を完全燃焼させることができ、ＮＯｘの発生を抑えることが可能になる。 In the incineration facility, a part of the exhaust gas treated by the exhaust gas treatment facility is extracted as recirculated exhaust gas, and the extracted recirculated exhaust gas is returned to the primary combustion chamber between the secondary combustion air supply port and the stoker. There is something like that. When the recirculated exhaust gas is supplied in this way, the atmosphere of the primary combustion chamber can be changed to a weakly reducing atmosphere, and further, the mixture is stirred and mixed by supplying the recirculated exhaust gas, and the gas concentration and temperature of this part are made uniform. Can do. Thereby, unburned gas components and unburned substances can be completely burned, and generation of NOx can be suppressed.

特開２００９−１０３３８１号公報JP 2009-103381 A

ここで、例えば特許文献１に開示された焼却設備では、焼却炉内の温度分布を計測あるいはシミュレーションにより推定し、８００〜１０００℃の温度範囲の領域に脱硝薬剤を噴霧するようにしている。このため、焼却炉内（燃焼ガス流路）の温度分布の計測手段やシミュレーション装置を組み込むことが必要になり、複雑かつ高価な装置構成になるという問題があった。 Here, for example, in the incineration facility disclosed in Patent Document 1, the temperature distribution in the incinerator is estimated by measurement or simulation, and the denitration drug is sprayed in a temperature range of 800 to 1000 ° C. For this reason, it is necessary to incorporate a temperature distribution measuring means and a simulation device in the incinerator (combustion gas flow path), resulting in a complicated and expensive device configuration.

本発明の焼却設備は、被焼却物を搬送させながら燃焼させる燃焼部と、被焼却物が燃焼することで発生する燃焼ガスを外部に導く燃焼ガス流路と、前記燃焼部に対して一次燃焼空気を供給する一次燃焼空気供給部と、前記燃焼ガス流路に対して二次燃焼空気を供給する二次燃焼空気供給部と、前記燃焼ガス流路を流通した前記燃焼ガスを処理した後の排ガスを、前記一次燃焼空気供給部と前記二次燃焼空気供給部の間の前記燃焼ガス流路に還流させ、再循環排ガスとして供給する再循環排ガス供給部と、前記二次燃焼空気供給部と前記再循環排ガス供給部の間の前記燃焼ガス流路に脱硝薬剤を供給する第１脱硝薬剤供給部とを備えていることを特徴とする。 An incineration facility according to the present invention includes a combustion section that burns while conveying an incinerated object, a combustion gas passage that guides combustion gas generated when the incinerated object burns, and primary combustion with respect to the combustion section A primary combustion air supply section for supplying air, a secondary combustion air supply section for supplying secondary combustion air to the combustion gas flow path, and after processing the combustion gas flowing through the combustion gas flow path A recirculated exhaust gas supply unit that recirculates exhaust gas to the combustion gas flow path between the primary combustion air supply unit and the secondary combustion air supply unit and supplies the exhaust gas as recirculated exhaust gas; and the secondary combustion air supply unit; And a first denitration chemical supply unit that supplies a denitration chemical to the combustion gas flow path between the recirculation exhaust gas supply units.

また、本発明の焼却設備においては、前記二次燃焼空気供給部よりも前記燃焼ガスの流通方向下流側に脱硝薬剤を供給する第２脱硝薬剤供給部を備えていることが望ましい。 In addition, the incineration facility of the present invention preferably includes a second denitration chemical supply unit that supplies a denitration chemical downstream of the secondary combustion air supply unit in the flow direction of the combustion gas.

さらに、本発明の焼却設備においては、前記燃焼部と前記第１脱硝薬剤供給部の間、且つ前記燃焼部の被焼却物の搬送方向下流端側の内部ガスを抜き出し、前記二次燃焼空気供給部から前記二次燃焼空気とともに前記燃焼ガス流路に供給する内部ガス引抜供給部を備えていることがより望ましい。 Further, in the incineration facility of the present invention, the internal combustion gas is extracted between the combustion section and the first denitration chemical supply section and on the downstream end side of the combustion section in the conveying direction of the incinerated object, and the secondary combustion air supply It is more preferable to provide an internal gas extraction supply section that supplies the combustion gas flow path together with the secondary combustion air from the section.

本発明の焼却設備においては、排ガス処理設備で処理された排ガスの一部を再循環排ガスとして一次燃焼空気供給部と二次燃焼空気供給部の間の燃焼ガス流路（一次燃焼室）に還流させることにより、再循環排ガスによってこの部分の燃焼ガスを撹拌混合し、ガス成分の濃度や温度を均一化させることができる。 In the incineration facility of the present invention, a part of the exhaust gas treated in the exhaust gas treatment facility is recirculated to the combustion gas flow path (primary combustion chamber) between the primary combustion air supply unit and the secondary combustion air supply unit. By doing so, the combustion gas of this part can be stirred and mixed by the recirculated exhaust gas, and the concentration and temperature of the gas component can be made uniform.

そして、このように再循環排ガスの供給によって撹拌混合され、例えば９５０〜１０００℃前後の温度で、且つ１〜２ｖｏｌ％程度以下の酸素濃度で均一化された二次燃焼空気供給部と再循環排ガス供給部の間に、第１脱硝薬剤供給部から脱硝薬剤を供給すると、短時間で、効率的且つ効果的にＮＯｘを低減することが可能になり、例えば７０％を超える高脱硝率を実現することが可能になる。 Then, the secondary combustion air supply unit and the recirculated exhaust gas that are stirred and mixed by supplying the recirculated exhaust gas as described above and made uniform at, for example, a temperature of about 950 to 1000 ° C. and an oxygen concentration of about 1 to 2 vol% or less. When the denitration drug is supplied from the first denitration drug supply unit between the supply units, it becomes possible to reduce NOx efficiently and effectively in a short time, and achieve a high denitration rate exceeding 70%, for example. It becomes possible.

よって、本発明の焼却設備によれば、従来のように焼却炉内の温度分布の計測手段やシミュレーション装置を組み込むことを不要にし、再循環排ガス供給部を設けるとともに、二次燃焼空気供給部と再循環排ガス供給部の間に脱硝薬剤を供給する第１脱硝薬剤供給部を設けるという構成によって、効率的且つ効果的にＮＯｘを低減させることが可能になる。 Therefore, according to the incineration facility of the present invention, it is not necessary to incorporate a temperature distribution measuring means or a simulation device in the incinerator as in the prior art, a recirculation exhaust gas supply unit is provided, and a secondary combustion air supply unit is provided. By providing the first denitration chemical supply unit that supplies the denitration chemical between the recirculation exhaust gas supply units, it becomes possible to reduce NOx efficiently and effectively.

本発明の一実施形態に係る焼却設備を示す図である。It is a figure which shows the incineration equipment which concerns on one Embodiment of this invention. 燃焼ガスの酸素濃度の違いによる燃焼ガス温度と脱硝率の関係を示す図である。It is a figure which shows the relationship between the combustion gas temperature by the difference in the oxygen concentration of combustion gas, and a NOx removal rate. 本発明の一実施形態に係る焼却設備の変更例を示す図である。It is a figure which shows the example of a change of the incineration equipment which concerns on one Embodiment of this invention.

以下、図１及び図２を参照し、本発明の一実施形態に係る焼却設備について説明する。なお、本実施形態は、都市ごみなどの被焼却物を焼却処理するための焼却設備に関するものである。 Hereinafter, with reference to FIG.1 and FIG.2, the incineration equipment which concerns on one Embodiment of this invention is demonstrated. In addition, this embodiment is related with the incineration equipment for incinerating to-be-incinerated objects, such as municipal waste.

本実施形態の焼却設備（焼却プラント）Ａは、図１に示すように、被焼却物１を一時的に貯留するホッパ（ホッパシュート）２と、被焼却物１を燃焼させる焼却炉３と、ホッパ２からシュート部２ａを通じて連続的にフィードテーブル４上に供給された被焼却物１を所定のストロークで進退移動して焼却炉３内に押し出し投入するフィーダ５と、フィーダ５をフィードテーブル４上で進退移動させるためのフィーダ駆動装置６と、焼却炉３の底部側に、金属製の固定火格子とごみの流れ方向に往復運動する可動火格子を交互に配置してなるストーカ７と、送風機８から一次燃焼空気Ｓ１をストーカ７の各部に風箱９を通じて供給する一次燃焼空気供給部１０とを備えて構成されている。 As shown in FIG. 1, the incineration facility (incineration plant) A of the present embodiment includes a hopper (hopper chute) 2 for temporarily storing the incinerator 1, an incinerator 3 for burning the incinerator 1, and A feeder 5 that continuously feeds the incinerator 1 supplied from the hopper 2 through the chute 2a onto the feed table 4 with a predetermined stroke and pushes it into the incinerator 3, and feeds the feeder 5 onto the feed table 4. , A feeder drive device 6 for moving forward and backward, a stoker 7 in which a metal fixed grate and a movable grate reciprocating in the direction of dust flow are alternately arranged on the bottom side of the incinerator 3, and a blower The primary combustion air supply unit 10 is configured to supply the primary combustion air S1 from 8 to each part of the stoker 7 through the wind box 9.

また、ストーカ７は、本発明にかかる燃焼部であり、フィーダ５によって押し出されて焼却炉３内に落下した被焼却物１を受け、この被焼却物１の水分を蒸発させるとともに一部熱分解するための乾燥ストーカ部Ｍ１と、下方の風箱９から供給される一次燃焼空気Ｓ１によって、乾燥ストーカ部Ｍ１で乾燥した被焼却物１に着火させ、揮発分および固定炭素分を燃焼させる燃焼ストーカ部Ｍ２と、燃焼ストーカ部Ｍ２で燃焼されずに通過してきた固定炭素分等の未燃分を完全に灰になるまで燃焼させる後燃焼ストーカ部Ｍ３とを備えている。また、後燃焼ストーカ部Ｍ３の出口に灰出し口１１が設けられ、この灰出し口１１を通じて焼却炉３から灰を排出するように構成されている。 The stoker 7 is a combustion section according to the present invention. The stoker 7 receives the incinerated object 1 that has been pushed out by the feeder 5 and dropped into the incinerator 3, evaporates the moisture of the incinerated object 1, and partially pyrolyzes it. Combustion stoker that ignites the incinerated object 1 dried in the dry stoker part M1 by the dry stoker part M1 and the primary combustion air S1 supplied from the lower wind box 9 and burns volatile matter and fixed carbon content Part M2, and a post-combustion stoker part M3 that burns unburned components such as fixed carbon that have passed without being burned in the combustion stoker part M2 until they completely become ash. Further, an ash outlet 11 is provided at the outlet of the post-combustion stoker M 3, and the ash is discharged from the incinerator 3 through the ash outlet 11.

また、焼却炉３は、その内部が燃焼ガス流路１２とされ、さらに燃焼ガス流路１２の焼却炉３内は、ストーカ７の上方が一次燃焼室１３、一次燃焼室１３の上方が二次燃焼室１４とされ、燃焼ガスＲがストーカ７から一次燃焼室１３、一次燃焼室１３から二次燃焼室１４に向け、下方から上方に流通する。さらに、焼却炉３には、二次燃焼室１４の燃焼ガスＲの流通方向下流側に熱回収ボイラ１５が接続して配設されている。さらに、焼却炉３には、焼却炉３の炉壁に取り付けた供給ノズル１７を通じて送風機（不図示）から燃焼ガス流路１２に二次燃焼空気Ｓ２を供給する二次燃焼空気供給部１８が設けられている。 The interior of the incinerator 3 is a combustion gas flow path 12. Further, in the incinerator 3 of the combustion gas flow path 12, the upper side of the stoker 7 is the primary combustion chamber 13 and the upper side of the primary combustion chamber 13 is the secondary. Combustion gas R flows from the stoker 7 toward the primary combustion chamber 13 and from the primary combustion chamber 13 to the secondary combustion chamber 14 from below to above. Further, a heat recovery boiler 15 is connected to the incinerator 3 on the downstream side in the flow direction of the combustion gas R in the secondary combustion chamber 14. Further, the incinerator 3 is provided with a secondary combustion air supply unit 18 for supplying the secondary combustion air S2 from the blower (not shown) to the combustion gas passage 12 through a supply nozzle 17 attached to the furnace wall of the incinerator 3. It has been.

また、熱回収ボイラ１５で熱回収された排ガスＲ’は、減温塔１９、除塵装置（バグフィルタ）２０などの排ガス処理設備２１を通過して処理され、煙突２２から外部に排出される。 Further, the exhaust gas R ′ heat recovered by the heat recovery boiler 15 is processed through an exhaust gas processing facility 21 such as a temperature reducing tower 19 and a dust removing device (bag filter) 20, and is discharged from the chimney 22 to the outside.

さらに、本実施形態の焼却設備Ａには、排ガス処理設備２１で処理した後の排ガスＲ’を、一次燃焼空気供給部１０と二次燃焼空気供給部１８の間の燃焼ガス流路１２、すなわち一次燃焼室１３に送風機２３によって還流させ、炉壁に設けられた供給ノズル２４を通じ、再循環排ガスＳ３として供給する再循環排ガス供給部２５を備えている。 Furthermore, in the incineration facility A of the present embodiment, the exhaust gas R ′ after being treated by the exhaust gas treatment facility 21 is treated with the combustion gas flow path 12 between the primary combustion air supply unit 10 and the secondary combustion air supply unit 18, that is, A recirculated exhaust gas supply unit 25 is provided which is recirculated to the primary combustion chamber 13 by a blower 23 and supplied as recirculated exhaust gas S3 through a supply nozzle 24 provided on the furnace wall.

さらに、二次燃焼空気供給部１８と再循環排ガス供給部２５の間の燃焼ガス流路１２（一次燃焼室１３）に脱硝薬剤Ｐ１を供給する第１脱硝薬剤供給部２６を備えている。さらに、二次燃焼空気供給部１８よりも燃焼ガスＲの流通方向下流側（二次燃焼室１４）に脱硝薬剤Ｐ２を供給する第２脱硝薬剤供給部２７を備えている。また、第１脱硝薬剤供給部２６と第２脱硝薬剤供給部２７はそれぞれ、アンモニア水や尿素水などの脱硝薬剤Ｐ１、Ｐ２の貯蔵タンク（不図示）、送液ポンプ（不図示）、炉壁に設けられた供給ノズル３０、３１を備えて構成されている。 Furthermore, a first denitration chemical supply unit 26 that supplies the denitration chemical P1 to the combustion gas passage 12 (primary combustion chamber 13) between the secondary combustion air supply unit 18 and the recirculation exhaust gas supply unit 25 is provided. Further, a second denitration chemical supply unit 27 that supplies the denitration chemical P2 to the downstream side (secondary combustion chamber 14) in the flow direction of the combustion gas R from the secondary combustion air supply unit 18 is provided. Further, the first denitration drug supply unit 26 and the second denitration drug supply unit 27 are respectively a storage tank (not shown) of a denitration drug P1, P2 such as ammonia water or urea water, a liquid feed pump (not shown), a furnace wall. The supply nozzles 30 and 31 are provided.

そして、上記構成からなる本実施形態の焼却設備Ａで被焼却物１を焼却処理する際には、フィーダ５の駆動によって焼却炉３内のストーカ７上に落下した被焼却物１が、火格子の往復運動によって順次、乾燥ストーカ部Ｍ１、燃焼ストーカ部Ｍ２、後燃焼ストーカ部Ｍ３に搬送される。また、このとき、下方の風箱９から一次燃焼空気Ｓ１が、例えば空気比を０．８〜１．０程度として各ストーカ部Ｍ１、Ｍ２、Ｍ３に供給され、この一次燃焼空気Ｓ１によって被焼却物１が燃焼する。また、順次搬送されながら被焼却物１が燃焼し、後燃焼ストーカ部Ｍ３の出口に設けられた灰出し口１１から灰が外部に排出される。 When the incineration object 1 is incinerated with the incineration facility A of the present embodiment having the above-described configuration, the incineration object 1 that has fallen on the stalker 7 in the incinerator 3 by driving the feeder 5 is grate. Are sequentially conveyed to the dry stoker part M1, the combustion stoker part M2, and the post-combustion stoker part M3. At this time, the primary combustion air S1 is supplied from the lower wind box 9 to each of the stoker parts M1, M2, M3 with an air ratio of about 0.8 to 1.0, for example, and incinerated by the primary combustion air S1. Object 1 burns. Further, the incineration object 1 burns while being sequentially conveyed, and ash is discharged to the outside from an ash outlet 11 provided at the outlet of the post-combustion stoker M3.

ここで、往復運動するストーカ７の火格子上の被焼却物１に下方から供給されて、この被焼却物１を燃焼させるための一次燃焼空気Ｓ１はその流速がそれほど速くはない。また、一次燃焼空気Ｓ１で被焼却物１を燃焼させて発生した燃焼ガスＲは、一次燃焼室１３内において、そのガス成分の濃度や温度に分布が生じる。このため、一次燃焼空気Ｓ１と燃焼ガスＲとの混合に時間を要し、その成分が燃焼しきるまでに時間がかかる。 Here, the flow rate of the primary combustion air S1 supplied from below to the incineration object 1 on the grate of the stoker 7 reciprocating and combusting the incineration object 1 is not so high. In addition, the combustion gas R generated by burning the incineration object 1 with the primary combustion air S1 is distributed in the concentration and temperature of the gas component in the primary combustion chamber 13. For this reason, it takes time to mix the primary combustion air S1 and the combustion gas R, and it takes time until the components are completely combusted.

このため、本実施形態の焼却設備Ａでは、従来と同様に、焼却炉３内の一次燃焼室１３から上方に流れる燃焼ガスＲに対して、焼却炉３の燃焼ガス流路１２の途中で二次燃焼空気Ｓ２を例えば空気比０．２〜０．４程度で供給するようにし、燃焼ガスＲの未燃ガス成分の燃焼を促進させる。 For this reason, in the incineration facility A of the present embodiment, the combustion gas R flowing upward from the primary combustion chamber 13 in the incinerator 3 in the middle of the combustion gas flow path 12 of the incinerator 3 in the same manner as in the past. The next combustion air S2 is supplied, for example, at an air ratio of about 0.2 to 0.4, and combustion of the unburned gas component of the combustion gas R is promoted.

一方、上記のように被焼却物１を燃焼させる過程で、未燃ガスや未燃物の発生・燃焼に伴いＮＯｘが発生し、特に一次燃焼空気Ｓ１で被焼却物１を焼却した後の一次燃焼室１３内で多く発生する。 On the other hand, in the process of burning the incinerated object 1 as described above, NOx is generated with the generation and combustion of unburned gas and unburned object, and in particular the primary after incinerated object 1 is incinerated with the primary combustion air S1. Many occur in the combustion chamber 13.

これに対し、本実施形態の焼却設備Ａでは、まず、焼却炉３から熱回収ボイラ１５に送られ、この熱回収ボイラ１５で熱回収され、さらに排ガス処理設備２１の減温塔１９、除塵装置２０などで順次処理された排ガスＲ’の一部、例えば全排ガス量の１０〜３０％程度の排ガスＲ’を、再循環排ガスＳ３として一次燃焼空気供給部１０と二次燃焼空気供給部１８の間の燃焼ガス流路１２、すなわち一次燃焼室１３に還流させる。そして、このように再循環排ガスＳ３を一次燃焼室１３に供給すると、一次燃焼室１３の燃焼ガスＲが再循環排ガスＳ３によって撹拌混合される。これにより、一次燃焼室１３内のガス成分の濃度や温度が均一化され、且つ還元雰囲気で未燃ガスや未燃物の燃焼が促進され、これに伴い、ＮＯｘの発生が抑制される。 On the other hand, in the incineration facility A of the present embodiment, first, it is sent from the incinerator 3 to the heat recovery boiler 15 and is recovered by the heat recovery boiler 15, and further the temperature reducing tower 19 of the exhaust gas treatment facility 21, the dust removing device. A part of the exhaust gas R ′ that has been sequentially processed at 20 or the like, for example, about 10 to 30% of the total exhaust gas amount is used as the recirculated exhaust gas S3 in the primary combustion air supply unit 10 and the secondary combustion air supply unit 18. It is made to recirculate | reflux to the combustion gas flow path 12 in the meantime, ie, the primary combustion chamber 13. FIG. When the recirculated exhaust gas S3 is supplied to the primary combustion chamber 13 in this way, the combustion gas R in the primary combustion chamber 13 is agitated and mixed by the recirculated exhaust gas S3. Thereby, the density | concentration and temperature of the gas component in the primary combustion chamber 13 are equalize | homogenized, and combustion of unburned gas and an unburned substance is accelerated | stimulated in a reducing atmosphere, and generation | occurrence | production of NOx is suppressed in connection with this.

なお、フレッシュエアを一次燃焼室１３に供給し、一次燃焼室１３の燃焼ガスＲを撹拌混合させることも考えられるが、フレッシュエア中の成分によってＮＯｘが発生しやすくなる。 Although it is conceivable to supply fresh air to the primary combustion chamber 13 and stir and mix the combustion gas R in the primary combustion chamber 13, NOx is likely to be generated by the components in the fresh air.

次に、本実施形態の焼却設備Ａでは、脱硝薬剤供給部２６、２７から焼却炉３内の燃焼ガスＲ中に、アンモニア水や尿素水などの脱硝薬剤Ｐ１、Ｐ２を供給する。このように脱硝薬剤Ｐ１、Ｐ２を供給すると、焼却過程で生成されて燃焼ガスＲ（排ガスＲ’）中に含まれるＮＯｘに還元反応が生じ、排ガスＲ’中のＮＯｘが低減する。 Next, in the incineration facility A of this embodiment, denitration chemicals P1 and P2 such as ammonia water and urea water are supplied from the denitration chemical supply units 26 and 27 into the combustion gas R in the incinerator 3. When the denitration chemicals P1 and P2 are supplied in this way, a reduction reaction occurs in NOx produced in the incineration process and contained in the combustion gas R (exhaust gas R '), and NOx in the exhaust gas R' is reduced.

ここで、本願の発明者らは、脱硝薬剤Ｐ１、Ｐ２によるＮＯｘ低減効果に関して種々検討を行い、図２に示す燃焼ガスＲ中の酸素濃度の違いによる燃焼ガス温度と脱硝率の関係の知見をその成果として得ることができた。すなわち、この図２に示すように、燃焼ガスＲの酸素濃度が低くなるほど、脱硝率が高くなり、供給した脱硝薬剤Ｐ１、Ｐ２によって効率的にＮＯｘを低減できることが確認された。さらに、９００℃を超える高温域でも、やはり燃焼ガスＲの酸素濃度が低くなるほどに脱硝率が高くなることが確認された。 Here, the inventors of the present application have made various studies on the NOx reduction effect of the denitration agents P1 and P2, and obtained knowledge about the relationship between the combustion gas temperature and the denitration rate due to the difference in oxygen concentration in the combustion gas R shown in FIG. I was able to obtain it as a result. That is, as shown in FIG. 2, the lower the oxygen concentration of the combustion gas R, the higher the denitration rate, and it was confirmed that NOx can be efficiently reduced by the supplied denitration chemicals P1 and P2. Furthermore, even in a high temperature range exceeding 900 ° C., it was confirmed that the NOx removal rate increased as the oxygen concentration of the combustion gas R decreased.

この知見を得た本願の発明者らは、本実施形態の焼却設備Ａの焼却炉３内の温度や酸素濃度を調査し、二次燃焼空気供給部１８よりも下流側の二次燃焼室１４における燃焼ガスＲの酸素濃度がドライベースで５〜６ｖｏｌ％程度を示し、二次燃焼空気供給部１８と再循環排ガス供給部２５の間の一次燃焼室１３における燃焼ガスＲの酸素濃度がドライベースで３ｖｏｌ％以下を示すことを確認した。 The inventors of the present application who have obtained this knowledge investigate the temperature and oxygen concentration in the incinerator 3 of the incineration facility A of the present embodiment, and the secondary combustion chamber 14 on the downstream side of the secondary combustion air supply unit 18. The oxygen concentration of the combustion gas R in the case of the dry base is about 5-6 vol%, and the oxygen concentration of the combustion gas R in the primary combustion chamber 13 between the secondary combustion air supply unit 18 and the recirculation exhaust gas supply unit 25 is dry base. It confirmed that 3 vol% or less was shown.

そして、この知見に基づき、本実施形態の焼却設備Ａでは、まず、二次燃焼空気供給部１８と再循環排ガス供給部２５の間の一次燃焼室１３に脱硝薬剤Ｐ１を供給する第１脱硝薬剤供給部２６を設けるようにした。すなわち、二次燃焼空気供給部１８と再循環排ガス供給部２５の間は、再循環排ガスＳ３が供給され、撹拌混合によってガス成分の濃度や温度が均一化するとともに燃焼が促進され、これにより、例えば９５０〜１０００℃前後の温度で、且つ１〜２ｖｏｌ％程度の酸素濃度で均一化する。さらに、再循環排ガスＳ３の供給によって、この温度と酸素濃度の領域が広く形成される。 Based on this knowledge, in the incineration facility A of the present embodiment, first, the first denitration agent P1 that supplies the denitration agent P1 to the primary combustion chamber 13 between the secondary combustion air supply unit 18 and the recirculation exhaust gas supply unit 25. A supply unit 26 is provided. That is, the recirculated exhaust gas S3 is supplied between the secondary combustion air supply unit 18 and the recirculated exhaust gas supply unit 25, and the concentration and temperature of the gas components are made uniform by stirring and mixing, and combustion is thereby promoted. For example, homogenization is performed at a temperature of about 950 to 1000 ° C. and an oxygen concentration of about 1 to 2 vol%. Further, the supply of the recirculated exhaust gas S3 forms a wide range of this temperature and oxygen concentration.

よって、二次燃焼空気供給部１８と再循環排ガス供給部２５の間に第１脱硝薬剤供給部２６から脱硝薬剤Ｐ１を供給すると、図２に示したように、確実に７０％を超える高脱硝率で脱硝反応が生じ、短時間で、効率的且つ効果的にＮＯｘが低減することになる。 Therefore, when the denitration chemical P1 is supplied from the first denitration chemical supply unit 26 between the secondary combustion air supply unit 18 and the recirculated exhaust gas supply unit 25, as shown in FIG. A denitration reaction occurs at a high rate, and NOx is efficiently and effectively reduced in a short time.

さらに、本実施形態の焼却設備Ａにおいては、二次燃焼空気供給部１８よりも燃焼ガスＲの流通方向下流側に脱硝薬剤Ｐ２を供給する第２脱硝薬剤供給部２７を備え、従来と同様、二次燃焼室１４にも脱硝薬剤Ｐ２を供給する。この二次燃焼室１４では、８５０〜９５０℃前後の温度で、且つ二次燃焼空気Ｓ２の供給により酸素濃度が５〜６ｖｏｌ％程度になっているため、図２に示したように、５０％以上の脱硝効率で脱硝反応が生じることになる。 Furthermore, the incineration facility A of the present embodiment includes a second denitration chemical supply unit 27 that supplies the denitration chemical P2 downstream of the secondary combustion air supply unit 18 in the flow direction of the combustion gas R. The denitration agent P2 is also supplied to the secondary combustion chamber 14. In the secondary combustion chamber 14, the oxygen concentration is about 5 to 6 vol% at a temperature of about 850 to 950 ° C. and the supply of the secondary combustion air S 2, so that as shown in FIG. The denitration reaction occurs with the above denitration efficiency.

そして、このとき、本実施形態の焼却設備Ａでは、第１脱硝薬剤供給部２６から脱硝薬剤Ｐ１を供給し、既に７０％を超える脱硝率でＮＯｘを低減させた燃焼ガスＲが流通し、この燃焼ガスＲに対して第２脱硝薬剤供給部２７から脱硝薬剤Ｐ２供給することで、さらに５０％以上の脱硝効率でＮＯｘが低減することになる。このため、本実施形態では、第１脱硝薬剤供給部２６による効率的なＮＯｘ低減に加え、さらに第２脱硝薬剤供給部２７によるＮＯｘを低減させる２段階の脱硝処理が行われるため、従来と比較し、燃焼ガスＲ（排ガスＲ’）中のＮＯｘが確実に低濃度に抑えられる。 At this time, in the incineration facility A of the present embodiment, the denitration agent P1 is supplied from the first denitration agent supply unit 26, and the combustion gas R in which NOx is already reduced at a denitration rate exceeding 70% circulates. By supplying the denitration chemical P2 from the second denitration chemical supply unit 27 to the combustion gas R, NOx is further reduced with a denitration efficiency of 50% or more. For this reason, in the present embodiment, in addition to efficient NOx reduction by the first denitration drug supply unit 26, two-stage denitration processing for further reducing NOx by the second denitration drug supply unit 27 is performed. Thus, NOx in the combustion gas R (exhaust gas R ′) is surely suppressed to a low concentration.

また、従来のように二次燃焼室１４にのみ脱硝薬剤Ｐ２を供給する場合には、アンモニアなどの脱硝薬剤Ｐ２の投入量を多くしてしまうと、未反応の脱硝薬剤Ｐ２が生じてしまい、排ガスＲ’とともに外部にリークすることになる。このため、従来、脱硝薬剤Ｐ２の投入量を制限することが必要であった。 In addition, when the denitration agent P2 is supplied only to the secondary combustion chamber 14 as in the prior art, if the input amount of the denitration agent P2 such as ammonia is increased, the unreacted denitration agent P2 is generated. It will leak to the outside together with the exhaust gas R ′. For this reason, conventionally, it has been necessary to limit the input amount of the denitration drug P2.

これに対し、本実施形態の焼却設備Ａでは、第１脱硝薬剤供給部２６によって二次燃焼空気供給部１８と再循環排ガス供給部２５の間の一次燃焼室１３に脱硝薬剤Ｐ１を供給するようにしているため、すなわち、１０００℃前後の高温場に脱硝薬剤Ｐ１を供給するようにしているため、脱硝薬剤Ｐ１を多く投入しても未反応になることがない。これにより、本実施形態の焼却設備Ａにおいては、従来のようにリークを防止するために脱硝薬剤Ｐ１の投入量を抑制する必要がなく、従来よりも多くの脱硝薬剤Ｐ１を投入することも可能になり、この点からも確実にＮＯｘの低減効果が得られることになる。 In contrast, in the incineration facility A of the present embodiment, the first denitration chemical supply unit 26 supplies the denitration chemical P1 to the primary combustion chamber 13 between the secondary combustion air supply unit 18 and the recirculation exhaust gas supply unit 25. In other words, since the denitration drug P1 is supplied to a high temperature field of about 1000 ° C., no reaction occurs even if a large amount of the denitration drug P1 is added. Thereby, in the incineration facility A of the present embodiment, it is not necessary to suppress the input amount of the denitration agent P1 in order to prevent leakage as in the prior art, and it is possible to introduce more denitration agent P1 than before. From this point, the NOx reduction effect is surely obtained.

したがって、本実施形態の焼却設備Ａにおいては、排ガス処理設備２１で処理された排ガスＲ’の一部を再循環排ガスＳ３として一次燃焼空気供給部１０と二次燃焼空気供給部１８の間の燃焼ガス流路１２、すなわち一次燃焼室１３に還流させることにより、この一次燃焼室１３の燃焼ガスＲを再循環排ガスＳ３によって撹拌混合することができ、これにより、一次燃焼室１３内のガス成分の濃度や温度を均一化することができる。 Therefore, in the incineration facility A of the present embodiment, combustion between the primary combustion air supply unit 10 and the secondary combustion air supply unit 18 uses a part of the exhaust gas R ′ treated by the exhaust gas treatment facility 21 as the recirculated exhaust gas S3. By recirculating to the gas flow path 12, that is, the primary combustion chamber 13, the combustion gas R in the primary combustion chamber 13 can be agitated and mixed by the recirculated exhaust gas S 3, and thereby the gas components in the primary combustion chamber 13 can be mixed. The concentration and temperature can be made uniform.

そして、本実施形態の焼却設備Ａでは、燃焼ガスＲの酸素濃度が低くなるほど、脱硝率が高くなり、また、９００℃を超える高温域でも、燃焼ガスＲの酸素濃度が低くなるほどに脱硝率が高くなるという本願の発明者らによる知見に基づいて、第１脱硝薬剤供給部２６により、二次燃焼空気供給部１８と再循環排ガス供給部２５の間の一次燃焼室１３に脱硝薬剤Ｐ１供給するようにしたことで、短時間で、効率的且つ効果的にＮＯｘが低減することが可能になる。 In the incineration facility A of the present embodiment, the NOx removal rate increases as the oxygen concentration of the combustion gas R decreases, and the NOx removal rate decreases as the oxygen concentration of the combustion gas R decreases even in a high temperature region exceeding 900 ° C. Based on the knowledge of the inventors of the present application that it becomes higher, the first denitration chemical supply unit 26 supplies the denitration chemical P1 to the primary combustion chamber 13 between the secondary combustion air supply unit 18 and the recirculation exhaust gas supply unit 25. By doing so, NOx can be efficiently and effectively reduced in a short time.

すなわち、二次燃焼空気供給部１８と再循環排ガス供給部２５の間が、再循環排ガスＳ３の供給によって撹拌混合され、且つ燃焼が促進されて、例えば９５０〜１０００℃前後の温度で、且つ１〜２ｖｏｌ％程度の酸素濃度で均一化されるため、この二次燃焼空気供給部１８と再循環排ガス供給部２５の間に脱硝薬剤Ｐ１を供給するように第１脱硝薬剤供給部２６を設けることで、例えば７０％を超える高脱硝率で脱硝反応が生じ、短時間で、効率的且つ効果的にＮＯｘを低減することが可能になる。 That is, between the secondary combustion air supply unit 18 and the recirculation exhaust gas supply unit 25 is stirred and mixed by supplying the recirculation exhaust gas S3, and combustion is promoted, for example, at a temperature of about 950 to 1000 ° C. and 1 Since the oxygen concentration is uniform at about ˜2 vol%, the first denitration drug supply unit 26 is provided so as to supply the denitration drug P1 between the secondary combustion air supply unit 18 and the recirculation exhaust gas supply unit 25. Thus, for example, a denitration reaction occurs at a high denitration rate exceeding 70%, and NOx can be efficiently and effectively reduced in a short time.

また、従来のように二次燃焼空気供給部１８よりも燃焼ガスＲの流通方向下流側にのみ（二次燃焼室１４にのみ）脱硝薬剤Ｐ２を供給する場合には、未反応の脱硝薬剤Ｐ２のリークを防止するため、脱硝薬剤Ｐ２の投入量を抑える必要があるが、本実施形態の焼却設備Ａでは、第１脱硝薬剤供給部２６によって二次燃焼空気供給部１８と再循環排ガス供給部２５の間に脱硝薬剤Ｐ１を供給するようにしているため、すなわち、１０００℃前後の高温場に脱硝薬剤Ｐ１を供給するようにしているため、脱硝薬剤Ｐ１を多く投入しても未反応になることがない。このため、多くの脱硝薬剤Ｐ１を投入することも可能になり、この点からも、確実にＮＯｘの低減効果を得ることが可能になる。 Further, when the denitration agent P2 is supplied only downstream of the secondary combustion air supply unit 18 in the flow direction of the combustion gas R (only to the secondary combustion chamber 14) as in the prior art, the unreacted denitration agent P2 is supplied. However, in the incineration facility A of the present embodiment, the secondary combustion air supply unit 18 and the recirculated exhaust gas supply unit are used by the first denitration chemical supply unit 26 in order to prevent the leakage of the NOx removal agent P2. Since the denitration agent P1 is supplied during 25, that is, the denitration agent P1 is supplied to a high temperature field of about 1000 ° C., even if a large amount of the denitration agent P1 is added, it does not react. There is nothing. For this reason, it is possible to introduce a large amount of the denitration agent P1, and also from this point, it is possible to reliably obtain the NOx reduction effect.

よって、本実施形態の焼却設備Ａによれば、従来のように焼却炉３内の温度分布の計測手段やシミュレーション装置を組み込むことを不要にし、再循環排ガス供給部２５に加え、二次燃焼空気供給部１８と再循環排ガス供給部２５の間に脱硝薬剤Ｐ１を供給する第１脱硝薬剤供給部２６を設けるという簡易な構成で、効率的且つ効果的にＮＯｘを低減させることが可能になる。 Therefore, according to the incineration facility A of the present embodiment, it is unnecessary to incorporate a temperature distribution measuring means and a simulation device in the incinerator 3 as in the prior art, and in addition to the recirculated exhaust gas supply unit 25, the secondary combustion air It is possible to efficiently and effectively reduce NOx with a simple configuration in which the first denitration drug supply unit 26 that supplies the denitration drug P1 is provided between the supply unit 18 and the recirculation exhaust gas supply unit 25.

また、本実施形態の焼却設備Ａにおいては、第１脱硝薬剤供給部２６に加え、二次燃焼空気供給部１８よりも燃焼ガスＲの流通方向下流側に脱硝薬剤Ｐ２を供給する第２脱硝薬剤供給部２７を備えることにより、第１脱硝薬剤供給部２６から供給した脱硝薬剤Ｐ１によってＮＯｘを低減させた燃焼ガスＲに対し、第２脱硝薬剤供給部２７から脱硝薬剤Ｐ２を供給し、さらにＮＯｘを低減させることができる。すなわち、第１脱硝薬剤供給部２６によって効率的にＮＯｘを低減させることに加え、さらに第２脱硝薬剤供給部２７によってＮＯｘを低減させる２段階の処理を施すことで、従来と比較し、燃焼ガスＲ（排ガスＲ’）中のＮＯｘを確実に低濃度に抑えることが可能になる。 Further, in the incineration facility A of the present embodiment, in addition to the first denitration chemical supply unit 26, the second denitration chemical P2 that supplies the denitration chemical P2 to the downstream side in the flow direction of the combustion gas R from the secondary combustion air supply unit 18. By providing the supply unit 27, the denitration agent P2 is supplied from the second denitration agent supply unit 27 to the combustion gas R in which NOx is reduced by the denitration agent P1 supplied from the first denitration agent supply unit 26, and further the NOx. Can be reduced. That is, in addition to efficiently reducing NOx by the first denitration chemical supply unit 26, and further by performing a two-stage process of reducing NOx by the second denitration chemical supply unit 27, combustion gas is compared with the conventional case. It becomes possible to reliably suppress NOx in R (exhaust gas R ′) to a low concentration.

以上、本発明に係る焼却設備の一実施形態について説明したが、本発明は上記の一実施形態に限定されるものではなく、その趣旨を逸脱しない範囲で適宜変更可能である。 As mentioned above, although one embodiment of incineration equipment concerning the present invention was described, the present invention is not limited to the above-mentioned one embodiment, and can be suitably changed in the range which does not deviate from the meaning.

例えば、本実施形態では、第１脱硝薬剤供給部２６に加え、二次燃焼空気供給部１８よりも下流側に脱硝薬剤Ｐ２を供給する第２脱硝薬剤供給部２７を備えて焼却設備Ａが構成されているものとしたが、本発明にかかる焼却設備は、二次燃焼空気供給部１８と再循環排ガス供給部２５の間にのみ脱硝薬剤Ｐ１を供給するように、第１脱硝薬剤供給部２６の一つの脱硝薬剤供給部を備えて構成してもよく、この場合においても、従来と比較し、十分に、効率的且つ効果的にＮＯｘを低減させることが可能である。 For example, in this embodiment, the incineration facility A includes the second denitration drug supply unit 27 that supplies the denitration drug P2 downstream from the secondary combustion air supply unit 18 in addition to the first denitration drug supply unit 26. However, the incineration facility according to the present invention is configured so that the denitration drug supply unit 26 supplies the denitration drug P1 only between the secondary combustion air supply unit 18 and the recirculation exhaust gas supply unit 25. In this case, NOx can be reduced sufficiently efficiently and effectively as compared with the conventional case.

また、図３に示すように、ストーカ（燃焼部）７と第１脱硝薬剤供給部２６の間で、且つストーカ７の被焼却物１の搬送方向下流側（図中：破線領域Ｇ）の内部ガス（燃焼ガス）Ｓ４の一部を抜き出し、二次燃焼空気供給部１８から二次燃焼空気Ｓ２とともに焼却炉３内の燃焼ガス流路１２に供給する内部ガス引抜供給部３２を備えていてもよい。 Further, as shown in FIG. 3, the inside of the stoker 7 (combustion unit) 7 and the first denitration chemical supply unit 26 and the downstream side in the conveying direction of the incinerated object 1 of the stoker 7 (in the figure: broken line region G). A part of the gas (combustion gas) S4 may be extracted and provided with an internal gas extraction supply unit 32 that supplies the secondary combustion air supply unit 18 to the combustion gas flow path 12 in the incinerator 3 together with the secondary combustion air S2. Good.

より具体的に、ストーカ７は、被焼却物１の搬送方向上流側から乾燥ストーカ部Ｍ１、燃焼ストーカ部Ｍ２、後燃焼ストーカ部Ｍ３が設けられ、搬送方向下流端側の後燃焼ストーカ部Ｍ３では、燃焼がある程度完了しているため、風箱９から供給した一次燃焼空気Ｓ１の酸素が消費されずに流通することになる。このため、ストーカ７の被焼却物１の搬送方向下流端側の燃焼ガスＲは、例えば酸素濃度が１８〜２０ｖｏｌ％程度であり、この酸素があまり消費されていない燃焼ガス（領域Ｇの内部ガスＳ４）を引き抜き、二次燃焼空気供給部１８から二次燃焼空気Ｓ２とともに焼却炉３内に供給することで、この内部ガスＳ４の酸素を二次燃焼に利用することが可能になる。これにより、二次燃焼空気供給部１８から供給するフレッシュエア（二次燃焼空気Ｓ２）の量を減らすことができ、結果として排ガス量を減らすことができる。よって、排ガスＲ’を処理する排ガス処理設備２１などに対する負荷を軽減することが可能になる。 More specifically, the stoker 7 is provided with a dry stoker part M1, a combustion stoker part M2, and a post-combustion stoker part M3 from the upstream side in the transport direction of the incinerated object 1, and in the post-combustion stoker part M3 on the downstream end side in the transport direction, Since the combustion is completed to some extent, the oxygen of the primary combustion air S1 supplied from the wind box 9 is circulated without being consumed. For this reason, the combustion gas R on the downstream end side in the transport direction of the incinerated object 1 of the stoker 7 has, for example, an oxygen concentration of about 18 to 20 vol%, and the combustion gas in which oxygen is not consumed much (internal gas in the region G). By extracting S4) and supplying it from the secondary combustion air supply unit 18 into the incinerator 3 together with the secondary combustion air S2, it becomes possible to use the oxygen of the internal gas S4 for secondary combustion. Thereby, the amount of fresh air (secondary combustion air S2) supplied from the secondary combustion air supply unit 18 can be reduced, and as a result, the amount of exhaust gas can be reduced. Therefore, it is possible to reduce the load on the exhaust gas treatment facility 21 for treating the exhaust gas R ′.

１被焼却物
２ホッパ
２ａシュート部
３焼却炉
４フィードテーブル
５フィーダ
６フィーダ駆動装置
７ストーカ
８送風機
９風箱
１０一次燃焼空気供給部
１１灰出し口
１２燃焼ガス流路
１３一次燃焼室
１４二次燃焼室
１５熱回収ボイラ
１７供給ノズル
１８二次燃焼空気供給部
１９減温塔
２０除塵装置
２１排ガス処理設備
２２煙突
２３送風機
２４供給ノズル
２５再循環排ガス供給部
２６第１脱硝薬剤供給部
２７第２脱硝薬剤供給部
３０供給ノズル
３１供給ノズル
３２内部ガス引抜供給部
Ａ焼却設備（焼却プラント）
Ｍ１乾燥ストーカ部
Ｍ２燃焼ストーカ部
Ｍ３後燃焼ストーカ部
Ｐ１脱硝薬剤
Ｐ２脱硝薬剤
Ｒ燃焼ガス
Ｒ’ 排ガス
Ｓ１一次燃焼空気
Ｓ２二次燃焼空気
Ｓ３再循環排ガス
Ｓ４内部ガス DESCRIPTION OF SYMBOLS 1 Incinerated object 2 Hopper 2a Chute part 3 Incinerator 4 Feed table 5 Feeder 6 Feeder drive device 7 Stoker 8 Blower 9 Wind box 10 Primary combustion air supply part 11 Ash outlet 12 Combustion gas flow path 13 Primary combustion chamber 14 Secondary Combustion chamber 15 Heat recovery boiler 17 Supply nozzle 18 Secondary combustion air supply unit 19 Temperature reducing tower 20 Dust removal device 21 Exhaust gas treatment equipment 22 Chimney 23 Blower 24 Supply nozzle 25 Recirculation exhaust gas supply unit 26 First denitration chemical supply unit 27 Second Denitration chemical supply unit 30 Supply nozzle 31 Supply nozzle 32 Internal gas extraction supply unit A Incineration facility (incineration plant)
M1 Dry stoker part M2 Combustion stoker part M3 Post combustion stoker part P1 Denitration chemical P2 Denitration chemical R Combustion gas R 'Exhaust gas S1 Primary combustion air S2 Secondary combustion air S3 Recirculation exhaust gas S4 Internal gas

Claims

被焼却物を搬送させながら燃焼させる燃焼部と、
被焼却物が燃焼することで発生する燃焼ガスを外部に導く燃焼ガス流路と、
前記燃焼部に対して一次燃焼空気を供給する一次燃焼空気供給部と、
前記燃焼ガス流路に対して二次燃焼空気を供給する二次燃焼空気供給部と、
前記燃焼ガス流路を流通した前記燃焼ガスを処理した後の排ガスを、前記一次燃焼空気供給部と前記二次燃焼空気供給部の間の前記燃焼ガス流路に還流させ、再循環排ガスとして供給する再循環排ガス供給部と、
前記二次燃焼空気供給部と前記再循環排ガス供給部の間の前記燃焼ガス流路に脱硝薬剤を供給する第１脱硝薬剤供給部とを備えていることを特徴とする焼却設備。 A combustion section for burning the incinerated material while conveying it;
A combustion gas passage for guiding combustion gas generated by burning the incinerated material to the outside;
A primary combustion air supply unit for supplying primary combustion air to the combustion unit;
A secondary combustion air supply unit for supplying secondary combustion air to the combustion gas flow path;
The exhaust gas after processing the combustion gas flowing through the combustion gas channel is recirculated to the combustion gas channel between the primary combustion air supply unit and the secondary combustion air supply unit and supplied as recirculated exhaust gas A recirculating exhaust gas supply unit,
An incineration facility comprising a first denitration chemical supply unit that supplies a denitration chemical to the combustion gas flow path between the secondary combustion air supply unit and the recirculation exhaust gas supply unit.

請求項１記載の焼却設備において、
前記二次燃焼空気供給部よりも前記燃焼ガスの流通方向下流側に脱硝薬剤を供給する第２脱硝薬剤供給部を備えていることを特徴とする焼却設備。 Incineration equipment according to claim 1,
An incineration facility comprising a second denitration chemical supply unit that supplies a denitration chemical downstream of the secondary combustion air supply unit in the flow direction of the combustion gas.

請求項１または請求項２に記載の焼却設備において、
前記燃焼部と前記第１脱硝薬剤供給部の間、且つ前記燃焼部の被焼却物の搬送方向下流端側の内部ガスを抜き出し、前記二次燃焼空気供給部から前記二次燃焼空気とともに前記燃焼ガス流路に供給する内部ガス引抜供給部を備えていることを特徴とする焼却設備。 In the incineration facility according to claim 1 or claim 2,
An internal gas is extracted between the combustion unit and the first denitration chemical supply unit and on the downstream end side in the conveyance direction of the incinerated material of the combustion unit, and the combustion is performed together with the secondary combustion air from the secondary combustion air supply unit An incineration facility comprising an internal gas extraction supply unit for supplying to a gas flow path.