【０００１】
【発明の属する技術分野】
本発明は、下水汚泥、し渣、都市ゴミ、産業廃棄物等の有機性汚泥を乾燥炭化処理後・賦活処理して吸着性能の高い活性炭化物を製造するようにした有機性汚泥の活性炭化物製造方法及び装置に関する。
【０００２】
【従来の技術】
従来、下水汚泥等の有機性汚泥の処理方法として、汚泥を乾燥、炭化、賦活処理して炭化物を製造し、この炭化物を吸着剤等として利用することが行われている。
【０００３】
下水汚泥等の汚泥から吸着能力の高い炭化物を製造するためには、汚泥乾燥炭化処理して得られる炭化物を賦活して吸着能力を高めるのに必要な反応表面積を多く確保する必要がある。また、汚泥の炭化・賦活処理においては、炭化処理の前段で発生した水蒸気及び炭化処理で発生した炭酸ガスを賦活に利用できる流れを作り出して、炭化物の賦活反応を効率的に行い吸着性能を向上させる必要がある。
【０００４】
このような有機性汚泥の炭化物製造方法として特開平１１−１９９２１５号がある。
かかる技術は、廃棄物固形燃料を炭化炉で熱分解して炭化物とし、この炭化物を酸処理装置により液相酸化した後、ガス賦活装置に導いて水蒸気によりガス賦活して活性炭とし、前記熱分解炉での廃棄物固形燃料の熱分解による炭化の過程で発生する熱分解ガスを溶融炉に導いて燃焼するとともに該熱分解ガス中の飛灰を溶融して溶融スラグとして回収し、前記溶融炉からの燃焼排ガスを廃熱ボイラに導いて熱回収し、前記ガス賦活装置のガス賦活用の水蒸気として前記熱回収により得られた水蒸気の一部を使用する活性炭化物の製造方法にある。
【０００５】
しかしながらかかる技術は、炭化炉で熱分解した炭化物を酸処理装置により液相酸化するという特別な処理工程が必要であり、然も実施例に窒素雰囲気のガス賦活装置で水蒸気により５時間の賦活して活性炭を製造すると記載されているように、賦活装置が窒素雰囲気に限定され、更に賦活時間も５時間必要であり、装置及び賦活時間が長時間であるという欠点を有す。
【０００６】
又特開２００１−５８８０６には、循環乾燥汚泥に汚泥脱水ケーキを混合し、これを解砕機で粉砕・乾燥させ、乾燥汚泥を気流乾燥管でさらに乾燥させた後、乾燥汚泥を含む気流をサイクロンで固気分離し、乾燥汚泥の大部分を循環乾燥汚泥とし、残りの乾燥汚泥を活性炭化炉で炭化・賦活して活性炭化物を製造し、サイクロンからの乾燥排ガスの一部を活性炭化炉排ガスと熱交換して乾燥排ガスを加熱し、この加熱気体を解砕機に供給するもので、更に活性炭化物の原料となる粉体状の乾燥汚泥を、間接加熱方式である活性炭化装置に導入して、活性炭化物を製造する技術である。
【０００７】
しかしながらかかる技術も前記した通り脱水ケーキに着目しているが、脱水ケーキの混合、解砕機による粉砕乾燥、気流乾燥管での二次乾燥という工程が煩雑であるとともに、活性炭化炉が、乾燥汚泥中の水分を炭化処理の前段で蒸発させ、ついで、乾燥汚泥を熱分解して炭化処理し、炭化された汚泥を、炭化処理の前段で発生した水蒸気及び熱分解時に発生する炭酸ガスにより賦活処理して活性炭化物を製造するというように、その構成が煩雑であり、具体的には活性炭化炉内にスクリューコンベアをに設けて、活性炭化炉のケーシング（円筒管）内に投入された粉体状の乾燥汚泥を、ケーシング内に設けられたスクリューコンベアによってケーシング内を移動させ、ケーシング内の汚泥と熱分解ガス等の流れを並流として、ケーシング内の上流側が乾燥汚泥中の水分を蒸発させるための低温の乾燥ゾーン及びケーシング内を汚泥の移動方向に進むにつれて乾燥汚泥を熱分解して炭化するための炭化ゾーンとし、更にケーシング内の下流側が乾燥ゾーンで発生した水蒸気及び炭化ゾーンで発生した炭酸ガスにより炭化された汚泥を賦活するための高温の賦活ゾーンとして構成されているように１の炉内に３つのゾーンを設けねばならない。
【０００８】
更に特開２０００−２３９０１号には、廃棄物を熱分解炉で熱分解し、生成された熱分解ガスとチャーを溶融炉で燃焼させて溶融スラグとして取り出す廃棄物処理設備において、チャーと、熱分解ガス中から捕集したダストの一方又は双方を、溶融炉からの高温排ガスを熱源とする賦活炉に活性炭原料として供給するとともに該賦活炉に、廃熱回収により生じた水蒸気を送給して、活性炭原料を賦活処理し、活性炭を製造する技術が開示されている。
【０００９】
しかしながらかかる技術においても賦活炉内の活性炭原料を８００〜１０００℃の処理条件で水蒸気で賦活処理して活性炭を得るようにすると開示されているのみで、その好ましい特定が何等なされていない。
【００１０】
【発明が解決しようとする課題】
本発明はかかる技術的課題に鑑み、有機性廃棄物を乾燥炭化処理後・炭酸ガスを含む燃焼排ガスを炭化物に直接作用させて、特別に新たなエネルギを要さずに、簡素なシステムで賦活処理して吸着性能の高い活性炭化物を容易に製造出来る活性炭化物製造方法とその装置を提供することを目的とする。
【００１１】
【課題を解決するための手段】
本発明はかかる課題を解決するために、有機性廃棄物を乾燥炭化処理後・炭酸ガスを含む燃焼排ガスを改質炉内に投入した炭化物に直接作用させて賦活処理して吸着性能の高い活性炭化物（例えば吸着剤）を製造する方法において、賦活温度が８００〜９５０℃、好ましくは８５０〜９００℃、Ｏ２濃度は１〜５％、水蒸気濃度が３４〜５０％の燃焼排ガスを用いて賦活時間を４５〜９０分、好ましくは６０〜９０分に設定して賦活処理を行うことを特徴とする。
【００１２】
かかる発明によれば、賦活前約８〜２３ｍ２／ｇの比表面積が２００ｍ２／ｇに増大するとともに、ベンゼン吸着力が賦活前０％だったものが、３〜４％に増大した。
この場合前記有機性廃棄物には高含水率の下水汚泥を用いることにより、水蒸気濃度を３４〜５０％に維持することが容易となるが、最終的には特別な制御手段が必要となる。
ここで、賦活とはガスによる炭素の酸化反応で炭化物の表面を侵食させることによって、炭化物の微細孔構造をより発達させることである。（活性炭−基礎と応用 第２刷 炭素材料学会編、１９７６年、講談社）
【００１３】
請求項２記載の発明は前記発明を円滑に達成するための装置に関する発明で、
前記有機性廃棄物の熱分解ガスを利用して燃焼排ガスを製造する製造手段と、該燃焼排ガスを改質炉に投入する際に、その賦活温度が８００〜９５０℃、好ましくは８５０〜９００℃、Ｏ２濃度は１〜５％、水蒸気濃度が３４〜５０％に制御する制御手段を設け、該改質炉内での賦活時間を４５〜９０分、好ましくは６０〜９０分に設定して賦活処理を行うことを特徴とする。
この場合、前記改質炉は燃焼排ガスと炭化物が直接接触する改質炉、特にロータリキルン若しくは気泡流動層炉が好ましい。
【００１４】
かかる発明によれば、賦活時間が９０分以下と大幅に短縮されるとともに、炭化炉から途中の改質操作工程を経ずに、直接炭化物を投入して改質がなされるために、装置構成が極めて簡単化する。
【００１５】
そして前記制御手段の１として前記燃焼排ガスを製造する製造手段と改質炉間の燃焼排ガス供給ラインに温度制御手段若しくは水蒸気濃度制御手段を介在させたことを特徴とする。
かかる発明によれば、前記燃焼排ガス供給ラインで直接燃焼排ガスの簡単に制御可能となり、且つタイムラグが生じない。
【００１６】
前記制御手段の２として、前記燃焼排ガスを製造する製造手段の一次空気、熱分解ガス若しくは二次空気の制御により、酸素濃度と温度の制御を図ることを特徴とする。
かかる発明によれば、前記燃焼排ガスを製造する製造手段の一次空気、熱分解ガス若しくは二次空気の制御は既存の装置でも行っており、それを利用することにより既存設備の改造で足りる。
【００１７】
前記制御手段の３として、前記燃焼排ガスを製造する製造手段の一次空気、熱分解ガス若しくは二次空気の供給ラインに水蒸気濃度調整手段を介在させたことを特徴とする。
水蒸気濃度の制御は有機廃棄物の種類及び天候等にも左右されるが、かかる発明によれば水蒸気濃度調整手段を設けたために、このような水蒸気濃度の変動にも対応できる。
【００１８】
前記制御手段の４として、前記改質炉から排出される第２の排ガスを、改質炉に供給する燃焼排ガスラインに戻す戻しラインを設け、前記第２の排ガスの戻し量制御により、酸素濃度、温度、水蒸気濃度のいずれかを制御することを特徴とする。
かかる発明によれば前記燃焼排ガスを製造する製造手段側でどのような燃焼排ガスが製造されてもこれを効果的に制御できる。
特に前記改質炉から排出される第２の排ガスは改質により水蒸気濃度や温度が低下しており、これを燃焼排ガスラインに戻すことにより、水蒸気や酸素濃度が高めの場合に有効である。
【００１９】
前記制御手段の５として、前記戻しラインに予冷・加熱器、水蒸気濃度調整手段、戻し排ガス量調整手段の内、一の制御手段を介装したことを特徴とする。
かかる発明によれば前記燃焼排ガスを製造する製造手段側でどのような燃焼排ガスが製造されてもこれを効果的に制御できるとともに、前記戻しラインに予冷・加熱器、水蒸気濃度調整手段、戻し排ガス量調整手段を適宜組み込むことによりいかなる種類の有機系廃棄物にも対応できる。
【００２０】
【発明の実施の形態】
以下、本発明を図に示した実施例を用いて詳細に説明する。但し、この実施例に記載される構成部品の寸法、形状、その相対配置などは特に特定的な記載がない限り、この発明の範囲をそれのみに限定する趣旨ではなく単なる説明例に過ぎない。
図３は本発明が適用される汚泥等有機系廃棄物を原料とする活性炭化物を含め多品種資源化製品の製造工程の一実施形態を概略的に示す図である。
図３において、多品種資源化製品の製造装置は、下水汚泥等の高水分含有有機性廃棄物１を投入する汚泥ホッパ３、該高水分含有汚泥の圧送ポンプ４、該汚泥の乾燥のみか、若しくは乾燥と炭化を行い粉体状チャーを製造する汚泥乾燥と炭化を選択的に行う乾燥−炭化炉５で、ロータリキルンから構成されている。又６はシールコンベヤで、スクリューコンベアで構成され、前記炭化炉５で炭化された粉体若しくは粒状チャーを外部より大気の侵入がない状態で、改質（賦活）装置７若しくは炭化物ホッパ８に選択的に搬送する。
【００２１】
そして、炭化物ホッパ８に貯留されたされた炭化物は、炭化物供給機９より熱分解ガス燃焼式灰溶融炉１０に送給され、灰溶融炉１０では、乾燥−炭化炉５で製造された熱分解ガスが循環ファン１５により導かれ、一方、ブロワ２０により吸引された空気を予熱器１４を介して灰溶融炉の一次空気として用いられて炭化物が灰溶融される。
該灰溶融炉１０で溶融された溶融灰は冷却されて結晶スラグ２８化され、結晶化スラグコンベヤ１１にてホッパ１２に貯留された後、トラック等で目的地搬送される。
【００２２】
１３は灰溶融炉１０上部に設けた二次燃焼室で乾燥−炭化炉５で製造され灰溶融炉１０に供給された熱分解ガスを、前記一次空気及び必要に応じてその途中位置に供給された二次空気により二次燃焼され８５０〜１３００℃前後まで高温化されて前記乾燥−炭化炉５と改質装置７に供給される。
又二次燃焼室１３で二次燃焼された燃焼排ガスは、乾燥−炭化炉５とともに炭化物賦活装置（改質装置７）に送給される。
この場合燃焼排ガスは、約８５０〜１１００℃、好ましくは９００〜１０００℃に制御して乾燥−炭化炉５の熱源ガスとして利用するのがよい。
【００２３】
又乾燥−炭化炉５に供給された排ガスは、予熱器１４、ガス冷却塔１６、バグフィルタ１７、誘引ファン１８を介して煙突１９等より大気に送出される。
【００２４】
かかる装置においては、乾燥−炭化炉５を乾燥機として使用する場合には、間接乾燥式ロータリーキルン型の乾燥−炭化炉５の炉鉄皮温度を約２００〜４００℃、回転数を約２〜３ｒｐｍ程度に制御する。一方乾燥−炭化炉５を炭化炉として使用する場合には、炉鉄皮温度を約５００〜７００℃、回転数を約１〜２ｒｐｍ程度に制御することにより、高含水の下水汚泥等の有機系廃棄物１は石灰（Ｃａ（ＯＨ）２）等の脱硫剤２とともに圧送ポンプ４により乾燥−炭化炉５に供給され、乾燥物２６または炭化物２７として選択的に取り出し有効利用される。
【００２５】
また、選択的に取り出した炭化物２７は、乾燥物／炭化物供給機９により熱分解ガス燃焼式灰溶融炉１０に供給し、溶融後、結晶化コンベヤ１１で結晶化スラグ粒塊物２８として取り出すことも可能であることは前記した通りである。
【００２６】
一方、乾燥−炭化炉５で発生する熱分解ガスは、循環ファン１５により熱分解ガス燃焼式灰溶融炉１０に供給され、完全燃焼し、炉内を約１４００〜１７００℃とし、燃焼パターンを、熱分解ガス燃焼−灰溶融炉１０、二次空気による燃焼−二次燃焼室１３の、二段燃焼とし、ＮＯｘ、ＣＯ、ＤＸＮの同時低減化を図る。また、二次燃焼室１３では二次空気の吹き込み量を制御して二次燃焼室出口温度が約９００℃〜１０００℃になるように制御を行う。
【００２７】
次に本発明の要部構成たる改質炉を説明する。
図１は本発明の第１実施例に係るロータリキルンを用いた改質炉７Ａで、前記二次燃焼室１３の９００〜１０００℃の燃焼排ガスを取り込み、乾燥−炭化炉５より取り込んだチャーからなる粉粒状炭化物を昇温させて賦活を行う。
（実施例１）
そしてかかるロータリキルンを用いてＯ２が４％、水蒸気濃度４０％、賦活温度９００℃の排ガスを用いて賦活時間（ロータリキルン内の）６０分で前記炭化炉から得られた炭化物の賦活処理を行ったところ、賦活前約８〜２３ｍ２／ｇの比表面積が２００ｍ２／ｇに増大するとともに、ベンゼン吸着力が賦活前０％だったものが、３〜４％に増大した。更に水蒸気濃度を３４〜５０％に変化させても同様な結果が得られたが、水蒸気濃度が３０％若しくは６０％では好ましい結果が得られなかった。
【００２８】
（実施例２）
つぎにＯ２を２％に低減させて、水蒸気濃度４０％、賦活温度９００℃の排ガスを用いて賦活時間６０分で前記炭化炉５から得られた炭化物の賦活処理を行ったところ、同様に賦活前約８〜２３ｍ２／ｇの比表面積が２００ｍ２／ｇに増大するとともに、ベンゼン吸着力が賦活前０％だったものが、４％に増大した。
（実施例３）
更にＯ２を５％に増大させて、水蒸気濃度４０％、賦活温度９００℃の排ガスを用いて賦活時間６０分で前記炭化炉５から得られた炭化物の賦活処理を行ったところ、同様に賦活前約８〜２３ｍ２／ｇの比表面積が１５０ｍ２／ｇに増大するとともに、ベンゼン吸着力が賦活前０％だったものが、３％に増大した。
【００２９】
（比較例１）
一方に水蒸気濃度４０％、賦活温度９００℃の窒素ガスを用いて賦活時間６０分で前記炭化炉から得られた炭化物の賦活処理を行ったところ、同様に賦活前約８〜２３ｍ２／ｇの比表面積の増大が１００ｍ２／ｇ程度であり、ベンゼン吸着力が２％程度の増大であった。
（比較例２）
一方にＯ２を８％に増大させて、水蒸気濃度４０％、賦活温度９００℃の排ガスを用いて賦活時間６０分で前記炭化炉５から得られた炭化物の賦活処理を行ったところ、同様に炭化物の燃焼が見られ賦活物質は得られなかった。
【００３０】
（実施例４）
Ｏ２が４％を維持して、水蒸気濃度４０％、賦活温度８５０℃の排ガスを用いて賦活時間（ロータリキルン内の）９０分で前記炭化炉５から得られた炭化物の賦活処理を行ったところ、賦活前約８〜２３ｍ２／ｇの比表面積が２００ｍ２／ｇに増大するとともに、ベンゼン吸着力が賦活前０％だったものが、３〜４％に増大した。更に水蒸気濃度を３４〜５０％に変化させても同様な結果が得られた。
（実施例５）
Ｏ２が４％を維持して、水蒸気濃度４０％、賦活温度９５０℃の排ガスを用いて賦活時間（ロータリキルン内で）５０分で前記炭化炉５から得られた炭化物の賦活処理を行ったところ、賦活前約８〜２３ｍ２／ｇの比表面積が２００ｍ２／ｇに増大するとともに、ベンゼン吸着力が賦活前０％だったものが、３〜４％に増大した。更に水蒸気濃度を３４〜５０％に変化させても同様な結果が得られた。
【００３１】
（比較例４）
Ｏ２が４％を維持して、水蒸気濃度４０％、賦活温度８００℃の排ガスを用いて賦活時間（ロータリキルン内の）３０分で前記炭化炉５から得られた炭化物の賦活処理を行ったところ、賦活前約８〜２３ｍ２／ｇの比表面積の増大も又、ベンゼン吸着力の増大も見られなかった。
（比較例５）
Ｏ２が４％を維持して、水蒸気濃度４０％、賦活温度１０００℃の排ガスを用いて賦活時間（ロータリキルン内の）９０分で前記炭化炉５から得られた炭化物の賦活処理を行ったところ、炭化物の燃焼が見られ賦活物質は得られなかった。
（比較例６）
更にＯ２が５％に増大させて、水蒸気濃度３５％、賦活温度９００℃の排ガスを用いて賦活時間１２０分で前記炭化炉５から得られた炭化物の賦活処理を行ったところ、同様に賦活前約８〜２３ｍ２／ｇの比表面積が１００ｍ２／ｇ程度に増大していたが一部に炭化物の燃焼が見られた。
【００３２】
かかる実験結果より賦活温度が８００〜９５０℃、好ましくは８５０〜９００℃、Ｏ２濃度は１〜５％、水蒸気濃度が３４〜５０％の燃焼排ガスを用いて賦活時間を４５〜９０分、好ましくは６０〜９０分に設定して賦活処理を行うのが良いことが理解できた。
【００３３】
次にかかる試験結果に基づく好ましい第１の実施形態を図１により説明する。７Ａはロータリキルン型の改質（賦活）炉で、炭化炉５よりの炭化物投入口の上部に燃焼排ガス投入ライン４１が接続され、該ライン４１は予冷器（熱交換器）３１を介して二次燃焼室１３の排ガス出口側と接続されている。
改質炉７Ａの入口側に位置するライン４１上及び二次燃焼室の出口側には夫々蒸気センサ３３、３６、酸素センサ３４、３７、温度センサ３５、３８が配置されており、夫々の検出値を制御回路３０に取り込む。
又二次燃焼室１３の炉途中に設けた二次空気ライン４２には水蒸気付加部３２を設けるとともに、二次空気導入量を調整するダンパ４３を設ける。
又灰溶融炉１０側の一次空気導入ライン４４、分解ガス導入ライン４５にも必要に応じてダンパ４６、４７を設ける。
【００３４】
そしてかかる装置において、賦活温度が８５０〜９００℃、Ｏ２濃度は１〜５％、水蒸気濃度が３４〜５０％の燃焼排ガスを用いて賦活時間を６０〜９０分に設定して賦活処理を行うの際の制御回路３０の制御動作について、説明する。
【００３５】
先ず温度については、二次燃焼室１３出口側の温度を温度センサ３８で見て９００℃より高い場合は、低温水蒸気が導入される予冷器（熱交換器）３１を作動させて、温度低下を図り、その確認を改質炉７Ａ入口側の温度センサ３５又は二次燃焼室１３出口側の温度センサ３８又は両者でみる。
又、二次燃焼室１３出口側の温度を温度センサ３８で見て８５０℃より低い場合は、二次空気ライン４２上のダンパ４３を開放して、温度上昇を図り、その確認を改質炉７Ａ入口側の温度センサ３５又は二次燃焼室１３出口側の温度センサ３８又は両者でみる。
【００３６】
水蒸気濃度は、二次燃焼室１３出口側の水蒸気濃度を水蒸気センサ３６で見て５０％より高く温度が高めの場合は分解ガスのダンパ４７を絞り、水蒸気濃度と温度低下を図り、その確認を改質炉７Ａ入口側の温度センサ３５と水蒸気センサ３３でみる。
一方、二次燃焼室１３出口側の水蒸気濃度を水蒸気センサ３６で見て３４％より低い場合は二次空気ラインの水蒸気付加部３２より水蒸気を供給し水蒸気濃度の増大を図り、その確認を改質炉７Ａ入口側の水蒸気センサ３３でみる。
【００３７】
酸素濃度については、二次燃焼室１３出口側の酸素濃度を酸素濃度センサ３７で見て５％より高い場合は、一次空気、二次空気のダンパ４３、４６を絞るか分解ガスのダンパ４７を開いて、酸素濃度低下を図り、その確認を改質炉７Ａ入口側の酸素センサ３４でみる。
又酸素濃度が３．４％より低い場合は、一次空気、二次空気のダンパ４３、４６を開くか分解ガスのダンパ４７を絞って、酸素濃度増加を図り、その確認を改質炉入口側の酸素センサ３４でみる。
又改質処理時間は回転数の制御により６０〜９０分の範囲に設定する。
【００３８】
次に気泡流動床を用いた第２の実施形態を図２により説明する。
７Ｂは気泡流動床を用いた改質（賦活）炉で、気泡流動床炉７Ｂよりの炭化物投入口を流動床の側部に設け、燃焼排ガス投入ライン５１が多数のノズル群で形成した散気室５２下部に接続され、燃焼排ガスにより流動床の流動撹拌が行われるように、又気泡流動床上部の排ガスライン５３には気泡流動床下部の一次空気ラインである燃焼排ガス投入ライン５１に戻す戻しライン５４が設けられ、該ライン５４は予冷熱器（熱交換器）５５、ダンパ５６及び水蒸気付加部５７を介して燃焼排ガス投入ライン５１に制御弁５９を介して接続されている。
【００３９】
改質炉７Ｂの入口側に位置する燃焼排ガス投入ライン５１上及び出口側の排ガスライン５３には夫々蒸気センサ３３、３６、酸素センサ３４、３７、温度センサ３５、３８が配置されており、夫々の検出値は制御回路３０に取り込まれる。
そしてかかる装置において、賦活温度が８５０〜９００℃、Ｏ２濃度は１〜５％、水蒸気濃度が３４〜５０％の燃焼排ガスを用いて賦活時間を６０〜９０分に設定して賦活処理を行うの際の制御回路の制御動作について、説明する。
【００４０】
先ず温度については、燃焼排ガス投入ライン５１の温度と温度センサ３５で見て９００℃より高い場合は、排ガスライン５３の温度を温度センサ３８で見ながらその差分を制御回路３０で演算しながら排ガスの戻しライン５４の予冷熱器（熱交換器）５５を作動させるか若しくはダンパ５６を開いて、温度低下を図り、その確認を燃焼排ガス投入ライン５１側の温度センサ３５でみる。
又前記温度センサ３５で見て８５０℃より低い場合は、排ガスライン５３の温度を温度センサ３８で見ながらその差分を制御回路３０で演算しながら排ガスの戻しライン５４の予冷熱器（熱交換器）５５を作動させるか若しくはダンパ５６を絞って、温度上昇を図り、その確認を燃焼排ガス投入ライン５１側の温度センサ３５でみる。
【００４１】
水蒸気濃度は、燃焼排ガス投入ライン５１の水蒸気濃度を水蒸気センサ３３で見て５０％より高く温度が高めの場合は、排ガスライン５３の水蒸気濃度を蒸気センサ３６で見つつその差分を制御回路３０で演算しながら排ガスの戻しラインのダンパを開いて、水蒸気濃度低下を図り、その確認を燃焼排ガス投入ライン５１側の水蒸気センサ３３でみる。
燃焼排ガス投入ライン５１の水蒸気濃度が３４％より低い場合は、排ガスの戻しライン５４の水蒸気付加器５７を作動させて、水蒸気濃度上昇を図り、その確認を燃焼排ガス投入ライン５１側の水蒸気センサ３３でみる。
【００４２】
酸素濃度については、燃焼排ガス投入ライン５１の酸素濃度を酸素濃度センサ３４で見て５％より高い場合は、排ガスライン５３の酸素濃度を酸素濃度センサ３７で見ながらその差分を制御回路３０で演算しつつ排ガスの戻しライン５４のダンパ５６を開いて、酸素濃度低下を図り、その確認を燃焼排ガス投入ライン５１側の酸素濃度センサ３４でみる。
又酸素濃度が１％より低い場合は、排ガスの戻しライン５４のダンパ５６をを絞って、酸素濃度増加をを図り、その確認燃焼排ガス投入ライン５１側の酸素センサ３４でみる。
又気泡流動床は０．５〜４ｍ／ｓに制御される。
【００４３】
【発明の効果】
以上記載のごとく本発明によれば、有機性廃棄物を乾燥炭化処理後・炭酸ガスを含む燃焼排ガスを炭化物に直接作用させて、特別に新たなエネルギを要さずに、簡素なシステムで賦活処理して吸着性能の高い活性炭化物を容易に製造出来る。
【図面の簡単な説明】
【図１】ロータリキルン型の改質（賦活）炉を用いた本発明の第１の実施形態の制御構成図である。
【図２】気泡流動層炉型の改質（賦活）炉を用いた本発明の第２の実施形態の制御構成図である。
【図３】本発明が適用される汚泥等有機系廃棄物を原料とする活性炭化物を含め多品種資源化製品の製造工程の一実施形態を概略的に示す図である。
【符号の説明】
１ 有機系廃棄物
５ 乾燥−炭化炉
７Ａ 改質炉
１３ 燃焼室
２７ 炭化物
３０ 制御回路
３３、３６ 蒸気センサ
３４、３７ 酸素センサ
３５、３８ 温度センサ
４１、５１ 燃焼排ガス投入ライン
４２ 二次空気ライン
４３、４６、４７、５６ ダンパ
４４ 一次空気導入ライン
４５ 分解ガス導入ライン
５３ 排ガスライン
５４ 戻しライン
５５ 予冷熱器（熱交換器）
５７ 水蒸気付加部
５９ 制御弁[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides activated carbon production of organic sludge such as sewage sludge, sewage residue, municipal garbage, industrial waste, etc., which is subjected to a dry carbonization treatment and an activation treatment to produce an activated carbon having high adsorption performance. Method and apparatus.
[0002]
[Prior art]
BACKGROUND ART Conventionally, as a method of treating organic sludge such as sewage sludge, drying, carbonizing, and activating the sludge to produce a carbide, and using the carbide as an adsorbent or the like have been performed.
[0003]
In order to produce a carbide having a high adsorptivity from sludge such as sewage sludge, it is necessary to secure a large reaction surface area required to activate the carbide obtained by sludge dry carbonization treatment to increase the adsorptive capacity. In addition, in the sludge carbonization and activation treatment, a stream that can be used to activate the steam generated in the previous stage of the carbonization treatment and the carbon dioxide gas generated in the carbonization treatment is created, and the activation reaction of the carbide is efficiently performed to improve the adsorption performance. Need to be done.
[0004]
Japanese Patent Application Laid-Open No. 11-199215 discloses a method for producing such organic sludge carbide.
This technology is to pyrolyze waste solid fuel in a carbonization furnace to form a carbide, oxidize this carbide in a liquid phase with an acid treatment device, guide it to a gas activation device, and activate the gas with water vapor to form activated carbon. The pyrolysis gas generated in the process of carbonization due to the pyrolysis of the waste solid fuel in the furnace is guided to a melting furnace for combustion, and the fly ash in the pyrolysis gas is melted and recovered as molten slag. The present invention is directed to a method for producing an activated carbide, wherein a combustion exhaust gas from a fuel cell is guided to a waste heat boiler to recover heat, and a part of the steam obtained by the heat recovery is used as steam for gas activation of the gas activation device.
[0005]
However, such a technique requires a special treatment step of subjecting the thermally decomposed carbide in a carbonization furnace to liquid phase oxidation by an acid treatment device. Naturally, in this embodiment, the gas activation device in a nitrogen atmosphere activates with steam for 5 hours. As described above, the activation apparatus is limited to a nitrogen atmosphere, and the activation time is also required to be 5 hours, which has the disadvantage that the activation time is long.
[0006]
Japanese Patent Application Laid-Open No. 2001-58806 discloses that a sludge dewatered cake is mixed with circulating dried sludge, crushed and dried by a crusher, and the dried sludge is further dried by a flash drying tube. In the activated carbonization furnace, a large portion of the dried sludge is converted into circulating dried sludge, and the remaining dried sludge is carbonized and activated in an activated carbonization furnace to produce activated carbides. Heat exchange heats the dried exhaust gas, and supplies this heated gas to the crusher.Furthermore, powdery dry sludge, which is a raw material of activated carbide, is introduced into an activated carbonization apparatus that is an indirect heating method. This is a technique for producing activated carbide.
[0007]
However, this technique also focuses on the dewatered cake as described above, but the steps of mixing the dewatered cake, pulverizing and drying with a crusher, and secondary drying with a flash drying tube are complicated, and the activated carbonization furnace is not suitable for drying sludge. The water inside is evaporated before the carbonization process, and then the dried sludge is pyrolyzed and carbonized, and the carbonized sludge is activated by the steam generated at the previous stage of the carbonization process and the carbon dioxide gas generated during the pyrolysis. The structure is complicated, such as manufacturing an activated carbonized material. Specifically, a screw conveyor is provided in an activated carbonized furnace, and the powder charged into a casing (cylindrical tube) of the activated carbonized furnace is used. The dried sludge in the shape is moved in the casing by a screw conveyor provided in the casing, and the sludge in the casing and the flow of pyrolysis gas and the like are made to flow in parallel to each other in the casing. The upstream side is a low-temperature drying zone for evaporating moisture in the dried sludge and the carbonization zone for pyrolyzing and drying the dried sludge as it proceeds in the moving direction of the sludge in the casing, and the downstream side in the casing is a drying zone. Three zones must be provided in one furnace so as to constitute a high-temperature activation zone for activating sludge carbonized by water vapor generated in the above and carbon dioxide gas generated in the carbonization zone.
[0008]
Further, Japanese Patent Application Laid-Open No. 2000-23901 discloses a waste treatment facility in which waste is pyrolyzed in a pyrolysis furnace, and the generated pyrolysis gas and char are burned in a melting furnace and taken out as molten slag. One or both of the dust collected from the cracked gas is supplied as an activated carbon raw material to an activation furnace using a high-temperature exhaust gas from a melting furnace as a heat source, and the activation furnace is supplied with steam generated by waste heat recovery. There is disclosed a technique for activating a raw material of activated carbon to produce activated carbon.
[0009]
However, even this technique only discloses that the activated carbon raw material in the activation furnace is activated with steam under the treatment conditions of 800 to 1000 ° C. to obtain activated carbon, but no preferred specification is made.
[0010]
[Problems to be solved by the invention]
The present invention has been made in view of the above technical problems, and has a simple system in which organic waste is subjected to a dry carbonization treatment, and a combustion exhaust gas containing carbon dioxide gas is allowed to directly act on the carbide, without requiring any special new energy. It is an object of the present invention to provide a method and an apparatus for producing an activated carbide which can easily produce an activated carbide having high adsorption performance by treating.
[0011]
[Means for Solving the Problems]
In order to solve this problem, the present invention provides an organic waste having a high adsorptive performance after a dry carbonization treatment and a combustion exhaust gas containing carbon dioxide gas is directly acted on a carbide introduced into a reforming furnace to perform an activation treatment. In a method for producing a carbide (for example, an adsorbent), activation is performed using combustion exhaust gas having an activation temperature of 800 to 950 ° C., preferably 850 to 900 ° C., an O 2 concentration of 1 to 5%, and a steam concentration of 34 to 50%. The activation treatment is performed by setting the time to 45 to 90 minutes, preferably 60 to 90 minutes.
[0012]
According to the invention, the specific surface area of activated close as 8~23m 2 / g are thereby increased to 200 meters 2 / g, as benzene adsorption force was 0% before activation was increased to 3-4%.
In this case, the use of sewage sludge having a high water content as the organic waste makes it easy to maintain the water vapor concentration at 34 to 50%, but ultimately requires special control means.
Here, the activation means that the surface of the carbide is eroded by an oxidation reaction of carbon by the gas, so that the micropore structure of the carbide is further developed. (Activated carbon-basics and applications, second edition, edited by the Society of Carbon Materials, 1976, Kodansha)
[0013]
The invention according to claim 2 relates to an apparatus for achieving the invention smoothly,
A production means for producing a combustion exhaust gas using the pyrolysis gas of the organic waste, and when the combustion exhaust gas is charged into a reforming furnace, the activation temperature is 800 to 950 ° C, preferably 850 to 900 ° C. , O 2 concentration is 1-5%, the control means water vapor concentration is controlled to 34 to 50% is provided, the activation time in the reforming furnace 45 to 90 minutes, preferably set to 60 to 90 minutes It is characterized by performing an activation treatment.
In this case, the reforming furnace is preferably a reforming furnace in which flue gas and carbide are in direct contact, particularly a rotary kiln or a bubble fluidized bed furnace.
[0014]
According to this invention, the activation time is greatly reduced to 90 minutes or less, and the reforming is performed by directly charging the carbide without passing through the reforming operation step in the middle from the carbonization furnace. Is greatly simplified.
[0015]
As one of the control means, a temperature control means or a steam concentration control means is interposed in a combustion exhaust gas supply line between the production means for producing the combustion exhaust gas and the reforming furnace.
According to this invention, the combustion exhaust gas can be easily controlled directly in the combustion exhaust gas supply line, and no time lag occurs.
[0016]
As the second control means, the oxygen concentration and the temperature are controlled by controlling the primary air, pyrolysis gas or secondary air of the production means for producing the combustion exhaust gas.
According to this invention, the control of the primary air, the pyrolysis gas or the secondary air of the production means for producing the combustion exhaust gas is also performed by the existing apparatus, and the use of the apparatus can be used to modify the existing equipment.
[0017]
As the third control means, a steam concentration adjusting means is interposed in a supply line of primary air, pyrolysis gas or secondary air for the production means for producing the combustion exhaust gas.
Although the control of the water vapor concentration depends on the type of the organic waste, the weather, and the like, according to the invention, the provision of the water vapor concentration adjusting means can cope with such a fluctuation of the water vapor concentration.
[0018]
As the control means 4, a return line for returning the second exhaust gas discharged from the reforming furnace to the combustion exhaust gas line supplied to the reforming furnace is provided, and by controlling the return amount of the second exhaust gas, the oxygen concentration is reduced. , Temperature, or water vapor concentration.
According to this invention, it is possible to effectively control whatever combustion exhaust gas is produced on the production means side for producing the combustion exhaust gas.
In particular, the second exhaust gas discharged from the reforming furnace has a reduced steam concentration or temperature due to reforming, and returning this to the combustion exhaust gas line is effective when the steam and oxygen concentrations are high.
[0019]
As the control means 5, one of the pre-cooling / heating device, the steam concentration adjusting means and the return exhaust gas amount adjusting means is interposed in the return line.
According to this invention, it is possible to effectively control whatever combustion exhaust gas is produced on the production means side for producing the combustion exhaust gas, and to provide a pre-cooling / heating device, a steam concentration adjusting means, a return exhaust gas to the return line. Any kind of organic waste can be handled by appropriately incorporating the amount adjusting means.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail using embodiments shown in the drawings. However, unless otherwise specified, the dimensions, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention, but are merely illustrative examples.
FIG. 3 is a diagram schematically showing an embodiment of a manufacturing process of a multi-product resource-recycling product including activated charcoal made from organic waste such as sludge to which the present invention is applied.
In FIG. 3, an apparatus for manufacturing a multi-product resource-based product includes a sludge hopper 3 into which high-moisture-containing organic waste 1 such as sewage sludge is injected, a pump 4 for feeding the high-moisture-containing sludge, and drying of the sludge. Alternatively, a drying-carbonization furnace 5 for selectively performing drying and carbonization of sludge for producing powdery char by performing drying and carbonization, comprising a rotary kiln. Reference numeral 6 denotes a seal conveyor, which is constituted by a screw conveyor, and selects the powder or granular char carbonized in the carbonizing furnace 5 to the reforming (activation) device 7 or the carbide hopper 8 in a state where no air enters from the outside. Transported.
[0021]
Then, the carbide stored in the carbide hopper 8 is sent from the carbide feeder 9 to the pyrolysis gas combustion type ash melting furnace 10, where the pyrolysis produced in the drying-carbonization furnace 5 is performed. The gas is guided by the circulation fan 15, while the air sucked by the blower 20 is used as the primary air of the ash melting furnace through the preheater 14 to melt the carbide.
The molten ash melted in the ash melting furnace 10 is cooled and converted into crystal slag 28, stored in a hopper 12 by a crystallization slag conveyor 11, and then transported to a destination by a truck or the like.
[0022]
Reference numeral 13 denotes a secondary combustion chamber provided at the upper part of the ash melting furnace 10, wherein the pyrolysis gas produced in the drying-carbonization furnace 5 and supplied to the ash melting furnace 10 is supplied to the primary air and, if necessary, to an intermediate position thereof. The secondary air is secondary-combusted by the generated secondary air, heated to about 850 to 1300 ° C., and supplied to the drying-carbonization furnace 5 and the reformer 7.
Further, the combustion exhaust gas secondary-combusted in the secondary combustion chamber 13 is sent to the carbide activation device (reforming device 7) together with the drying-carbonization furnace 5.
In this case, the combustion exhaust gas is controlled at about 850 to 1100 ° C., preferably 900 to 1000 ° C., and is preferably used as a heat source gas of the drying-carbonization furnace 5.
[0023]
Further, the exhaust gas supplied to the drying-carbonization furnace 5 is sent to the atmosphere from a chimney 19 and the like via a preheater 14, a gas cooling tower 16, a bag filter 17, an induction fan 18, and the like.
[0024]
In such an apparatus, when the drying-carbonization furnace 5 is used as a dryer, the furnace temperature of the furnace of the indirect drying rotary kiln type drying-carbonization furnace 5 is about 200 to 400 ° C., and the rotation speed is about 2 to 3 rpm. Control to the extent. On the other hand, when the drying-carbonization furnace 5 is used as a carbonization furnace, by controlling the furnace shell temperature to about 500 to 700 ° C. and the rotation speed to about 1 to 2 rpm, organic system such as sewage sludge with high water content can be obtained. The waste 1 is supplied to a drying-carbonization furnace 5 by a pump 4 together with a desulfurizing agent 2 such as lime (Ca (OH) 2 ), and is selectively taken out as a dried product 26 or a carbonized product 27 for effective use.
[0025]
The selectively removed carbide 27 is supplied to a pyrolysis gas combustion type ash melting furnace 10 by a dry matter / carbide feeder 9 and, after melting, is taken out as crystallized slag agglomerates 28 by the crystallization conveyor 11. Is also possible as described above.
[0026]
On the other hand, the pyrolysis gas generated in the drying-carbonization furnace 5 is supplied to the pyrolysis gas combustion type ash melting furnace 10 by the circulation fan 15 and completely burned, and the inside of the furnace is set to about 1400 to 1700 ° C., and the combustion pattern is Pyrolysis gas combustion-ash melting furnace 10, combustion with secondary air-secondary combustion in secondary combustion chamber 13 to simultaneously reduce NOx, CO, and DXN. The secondary combustion chamber 13 controls the amount of secondary air blown to control the secondary combustion chamber outlet temperature to be about 900 ° C to 1000 ° C.
[0027]
Next, a reforming furnace as a main part of the present invention will be described.
FIG. 1 shows a reforming furnace 7A using a rotary kiln according to the first embodiment of the present invention. The reforming furnace 7A takes in the combustion exhaust gas of the secondary combustion chamber 13 at 900 to 1000 ° C. Activated by raising the temperature of the powdery and granular carbides.
(Example 1)
Then, using the rotary kiln, the activation treatment of the carbide obtained from the carbonization furnace was performed for 60 minutes using an exhaust gas having an O 2 content of 4%, a water vapor concentration of 40%, and an activation temperature of 900 ° C. for 60 minutes (in the rotary kiln). When went, with a specific surface area of activated close as 8~23m 2 / g is increased to 200 meters 2 / g, as benzene adsorption force was 0% before activation was increased to 3-4%. Further, similar results were obtained when the water vapor concentration was changed to 34 to 50%, but a preferable result was not obtained when the water vapor concentration was 30% or 60%.
[0028]
(Example 2)
Next, O 2 was reduced to 2%, and the activation treatment of the carbide obtained from the carbonization furnace 5 was performed using an exhaust gas having a water vapor concentration of 40% and an activation temperature of 900 ° C. for an activation time of 60 minutes. with a specific surface area of activated close as 8~23m 2 / g is increased to 200 meters 2 / g, as benzene adsorption force was 0% before activation was increased to 4%.
(Example 3)
Further increases the O 2 5%, water vapor concentration of 40% and, when in activation time 60 minutes with activation temperature 900 ° C. of the exhaust gas was carried out activation treatment of the carbide obtained from the carbonization furnace 5, similarly activated with a specific surface area of close as 8~23m 2 / g is increased to 150 meters 2 / g, as benzene adsorption force was 0% before activation was increased to 3%.
[0029]
(Comparative Example 1)
On the other hand, when the carbide obtained from the carbonization furnace was activated for 60 minutes using a nitrogen gas having a steam concentration of 40% and an activation temperature of 900 ° C. for an activation time of about 8 to 23 m 2 / g before activation. The increase in specific surface area was about 100 m 2 / g, and the benzene adsorption power was about 2%.
(Comparative Example 2)
On the other hand, it increases the O 2 to 8%, water vapor concentration of 40% and, when in activation time 60 minutes with activation temperature 900 ° C. of the exhaust gas was carried out activation treatment of the carbide obtained from the carbonization furnace 5, as well Burning of carbides was observed and no activator was obtained.
[0030]
(Example 4)
The activation treatment of the carbide obtained from the carbonization furnace 5 was performed using an exhaust gas having a steam concentration of 40% and an activation temperature of 850 ° C. for 90 minutes (in a rotary kiln) while maintaining O 2 at 4%. where, the specific surface area of activated close as 8~23m 2 / g are thereby increased to 200 meters 2 / g, as benzene adsorption force was 0% before activation was increased to 3-4%. Similar results were obtained even when the water vapor concentration was changed to 34 to 50%.
(Example 5)
The activation treatment of the carbide obtained from the carbonization furnace 5 was performed using an exhaust gas having a water vapor concentration of 40% and an activation temperature of 950 ° C. for an activation time (in a rotary kiln) of 50 minutes while maintaining O 2 at 4%. where, the specific surface area of activated close as 8~23m 2 / g are thereby increased to 200 meters 2 / g, as benzene adsorption force was 0% before activation was increased to 3-4%. Similar results were obtained even when the water vapor concentration was changed to 34 to 50%.
[0031]
(Comparative Example 4)
The activation treatment of the carbide obtained from the carbonization furnace 5 was performed using an exhaust gas having a steam concentration of 40% and an activation temperature of 800 ° C. for an activation time of 30 minutes (in a rotary kiln) while maintaining O 2 at 4%. However, no increase in specific surface area of about 8 to 23 m 2 / g before activation and no increase in benzene adsorption power were observed.
(Comparative Example 5)
The activation treatment of the carbide obtained from the carbonization furnace 5 was performed using an exhaust gas having a steam concentration of 40% and an activation temperature of 1000 ° C. for 90 minutes (in a rotary kiln) while maintaining O 2 at 4%. However, combustion of the carbide was observed, and no activator was obtained.
(Comparative Example 6)
Further increasing O 2 is 5%, the water vapor concentration of 35% and, when in activation time 120 minutes using the activation temperature 900 ° C. of the exhaust gas was carried out activation treatment of the carbide obtained from the carbonization furnace 5, similarly activated the specific surface area of close as 8~23m 2 / g was increased to about 100 m 2 / g was observed burning of carbide part.
[0032]
According to the experimental results, the activation temperature is 800 to 950 ° C., preferably 850 to 900 ° C., the O 2 concentration is 1 to 5%, and the activation time is 45 to 90 minutes using the combustion exhaust gas having the steam concentration of 34 to 50%, preferably. It was understood that it is better to set the activation time to 60 to 90 minutes to perform the activation treatment.
[0033]
Next, a first preferred embodiment based on the test results will be described with reference to FIG. Reference numeral 7A denotes a rotary kiln type reforming (activation) furnace, in which a flue gas charging line 41 is connected to an upper portion of a carbide charging port from the carbonizing furnace 5, and the line 41 is connected via a precooler (heat exchanger) 31. It is connected to the exhaust gas outlet side of the next combustion chamber 13.
Steam sensors 33 and 36, oxygen sensors 34 and 37, and temperature sensors 35 and 38 are disposed on a line 41 located on the inlet side of the reforming furnace 7A and on an outlet side of the secondary combustion chamber, respectively. The value is taken into the control circuit 30.
The secondary air line 42 provided in the furnace of the secondary combustion chamber 13 is provided with the steam addition section 32 and a damper 43 for adjusting the secondary air introduction amount.
Dampers 46 and 47 are also provided on the primary air introduction line 44 and the cracked gas introduction line 45 on the ash melting furnace 10 side as needed.
[0034]
In such an apparatus, the activation treatment is performed by setting the activation time to 60 to 90 minutes using combustion exhaust gas having an activation temperature of 850 to 900 ° C., an O 2 concentration of 1 to 5%, and a steam concentration of 34 to 50%. The control operation of the control circuit 30 in this case will be described.
[0035]
First, as for the temperature, when the temperature at the outlet side of the secondary combustion chamber 13 is higher than 900 ° C. as seen by the temperature sensor 38, the precooler (heat exchanger) 31 into which low-temperature steam is introduced is operated to reduce the temperature. This is confirmed by the temperature sensor 35 on the inlet side of the reforming furnace 7A or the temperature sensor 38 on the outlet side of the secondary combustion chamber 13 or both.
When the temperature at the outlet side of the secondary combustion chamber 13 is lower than 850 ° C. as seen by the temperature sensor 38, the damper 43 on the secondary air line 42 is opened to increase the temperature, and the confirmation is made in the reforming furnace. The temperature is measured by the temperature sensor 35 on the 7A inlet side or the temperature sensor 38 on the outlet side of the secondary combustion chamber 13 or both.
[0036]
When the steam concentration at the outlet side of the secondary combustion chamber 13 is higher than 50% as seen by the steam sensor 36 and the temperature is higher, the damper 47 of the cracked gas is throttled to lower the steam concentration and the temperature, and the confirmation is made. The temperature sensor 35 and the steam sensor 33 on the inlet side of the reforming furnace 7A will be used.
On the other hand, when the steam concentration at the outlet side of the secondary combustion chamber 13 is lower than 34% as seen by the steam sensor 36, steam is supplied from the steam adding section 32 of the secondary air line to increase the steam concentration, and the confirmation is revised. With the steam sensor 33 on the inlet side of the furnace 7A.
[0037]
Regarding the oxygen concentration, when the oxygen concentration at the outlet side of the secondary combustion chamber 13 is higher than 5% as seen by the oxygen concentration sensor 37, the dampers 43 and 46 for the primary air and the secondary air are throttled or the damper 47 for the decomposition gas is turned off. When opened, the oxygen concentration is reduced, and confirmation is made with the oxygen sensor 34 on the inlet side of the reforming furnace 7A.
If the oxygen concentration is lower than 3.4%, open the primary air and secondary air dampers 43 and 46 or squeeze the cracked gas damper 47 to increase the oxygen concentration. With the oxygen sensor 34 of FIG.
The reforming time is set in the range of 60 to 90 minutes by controlling the number of revolutions.
[0038]
Next, a second embodiment using a bubble fluidized bed will be described with reference to FIG.
Numeral 7B denotes a reforming (activation) furnace using a bubble fluidized bed, in which a carbide inlet from the bubble fluidized bed furnace 7B is provided on the side of the fluidized bed, and a diffused gas formed by a combustion exhaust gas inlet line 51 formed by a number of nozzle groups. It is connected to the lower part of the chamber 52 and is returned to the flue gas input line 51 which is the primary air line at the lower part of the bubble fluidized bed so that the fluidized bed is stirred by the flue gas. A line 54 is provided, and the line 54 is connected to a flue gas input line 51 via a precooling heater (heat exchanger) 55, a damper 56, and a steam adding section 57 via a control valve 59.
[0039]
Steam sensors 33 and 36, oxygen sensors 34 and 37, and temperature sensors 35 and 38 are disposed on a flue gas input line 51 and an exhaust gas line 53 on the outlet side located on the inlet side of the reforming furnace 7B, respectively. Is taken into the control circuit 30.
In such an apparatus, the activation treatment is performed by setting the activation time to 60 to 90 minutes using combustion exhaust gas having an activation temperature of 850 to 900 ° C., an O 2 concentration of 1 to 5%, and a steam concentration of 34 to 50%. The control operation of the control circuit in this case will be described.
[0040]
First, when the temperature is higher than 900 ° C. as seen by the temperature of the flue gas input line 51 and the temperature sensor 35, the difference between the temperature of the flue gas line 53 is monitored by the control circuit 30 while the temperature of the flue gas line 53 is monitored by the temperature sensor 38. The pre-cooling heater (heat exchanger) 55 of the return line 54 is operated or the damper 56 is opened to lower the temperature, and the confirmation is made by the temperature sensor 35 on the flue gas input line 51 side.
If the temperature is lower than 850 ° C. as viewed by the temperature sensor 35, the difference between the temperature of the exhaust gas line 53 and the temperature of the exhaust gas return line 54 is calculated by the control circuit 30 while being monitored by the temperature sensor 38. ) 55 is operated or the damper 56 is squeezed to increase the temperature, and the temperature is checked by the temperature sensor 35 on the flue gas input line 51 side.
[0041]
When the steam concentration in the flue gas inlet line 51 is higher than 50% as seen by the steam sensor 33 and the temperature is higher, the difference is determined by the control circuit 30 while the steam concentration in the exhaust gas line 53 is seen by the steam sensor 36. By opening the damper of the exhaust gas return line while calculating, the concentration of water vapor is reduced, and the confirmation is made with the water vapor sensor 33 on the combustion exhaust gas input line 51 side.
When the steam concentration in the flue gas input line 51 is lower than 34%, the steam adder 57 in the exhaust gas return line 54 is operated to increase the steam concentration. Look at.
[0042]
Regarding the oxygen concentration, when the oxygen concentration in the flue gas input line 51 is higher than 5% as seen by the oxygen concentration sensor 34, the difference is calculated by the control circuit 30 while observing the oxygen concentration in the exhaust gas line 53 with the oxygen concentration sensor 37. Then, the damper 56 of the exhaust gas return line 54 is opened to reduce the oxygen concentration, and the confirmation is made by the oxygen concentration sensor 34 on the combustion exhaust gas input line 51 side.
On the other hand, when the oxygen concentration is lower than 1%, the damper 56 in the exhaust gas return line 54 is throttled to increase the oxygen concentration.
The bubble fluidized bed is controlled at 0.5 to 4 m / s.
[0043]
【The invention's effect】
As described above, according to the present invention, after the organic waste is subjected to the dry carbonization treatment, the combustion exhaust gas containing the carbon dioxide gas is allowed to act directly on the carbide, and is activated by a simple system without requiring any special new energy. Activated carbide with high adsorption performance can be easily produced by the treatment.
[Brief description of the drawings]
FIG. 1 is a control configuration diagram of a first embodiment of the present invention using a rotary kiln type reforming (activation) furnace.
FIG. 2 is a control configuration diagram of a second embodiment of the present invention using a reforming (activation) furnace of a bubble fluidized bed furnace type.
FIG. 3 is a diagram schematically showing an embodiment of a production process of a multi-product resource-based product including activated carbons made from organic waste such as sludge to which the present invention is applied.
[Explanation of symbols]
Reference Signs List 1 Organic waste 5 Drying-carbonization furnace 7A Reforming furnace 13 Combustion chamber 27 Carbide 30 Control circuit 33, 36 Steam sensor 34, 37 Oxygen sensor 35, 38 Temperature sensor 41, 51 Combustion exhaust gas input line 42 Secondary air line 43 , 46, 47, 56 Damper 44 Primary air introduction line 45 Decomposed gas introduction line 53 Exhaust gas line 54 Return line 55 Precooling heater (heat exchanger)
57 Steam addition section 59 Control valve
