JP4097999B2 - Control method and apparatus for pyrolysis gasification melting treatment plant, and program - Google Patents

Description

【００６１】
次に、ステップＳ３で、操作量不変時制御量変動分計算部３において、モデルを用いて、操作量不変時における制御量の変動量Δy0(k+i)を計算する。ここで、モデルは、流動床１１に吹き込まれる空気量（以下、「流動化空気量」と称する。）、熱分解ガス化炉１０への給塵量として給塵機速度（以下、「給塵機速度」と称する。）、ボイラ３０に備えられた蒸気弁３２の開度（以下、「蒸気弁開度」と称する。）を入力とし、流動床温度、ボイラドラム圧力、蒸気流量を出力とし、その他観測量として熱分解ガス化炉の炉内圧力を含むモデルであり、次式で表される。
【００６２】
【数２】

【００６３】
ここで、Δy0(k+i)は、今後操作量を変更しなかった場合の制御量の変動分である。従って、上述の式（数２）で表されるモデルを用いて、次式により、Δy0(k+i)が求まる。なお、次式では、観測量である熱分解ガス化炉の炉内圧力も現時刻以降の値も必要になるが、この炉内圧力の現時刻以降の値は別のモデルを使って推定している。
【００６４】
【数３】

【００６５】
そして、ステップＳ４で、制御量差分計算部６及び操作量不変時制御量偏差計算部７において、ステップＳ２で求めた目標軌道yr(k+i)と、ステップＳ３で求めた今後操作量を変更しなかった場合の制御量の変動分Δy0(k+i)と、現時点における制御量の実測値y(k)（流動床温度、ボイラドラム圧力、蒸気流量の実測値を要素に持つベクトル）とから、操作量不変更時における制御量と目標軌道との偏差Δye(k+i)を次式により計算する。
【００６６】
【数４】

【００６７】
次に、ステップＳ５で、制約条件設定部５において、操作入力Δu(k+i)に対し、制約条件を設定する。例えば、操作入力の上下限制約、変動幅の上下限制約は、次式で表される。
【００６８】
【数５】

【００６９】
また、制御量に関する制約条件なども操作量の関数として表されるから、これらの制約条件はすべて、次式の形に帰着することができる。
【００７０】
【数６】

【００７１】
そして、ステップＳ６で、操作量最適化計算部４において、未来の一定区間において、ステップＳ４で求めた偏差Δye(k+i)を補償するための偏差入力Δu(k)を、モデルを用いて求める。ここで、モデルは、流動化空気量、給塵機速度、蒸気弁開度を入力とし、流動床温度、ボイラドラム圧力、蒸気流量を出力とするモデルであり、次式で表される。
【００７２】
【数７】

【００７３】
さて、上述の式（数７）で表されたモデルから、現時点以降の操作入力が制御量に及ぼす影響を表す部分Δy+(k+i)を抽出すると次式となる。
【００７４】
【数８】

【００７５】
ここでの目的は、偏差Δye(k+i)を補償するための偏差入力Δu(k)を求めることである。そのためには、Δye(k+i)とΔy+(k+i)が、未来の一定区間において、できるだけ一致するような偏差入力Δu(k)を求めればよい。具体的には、上述の制約条件（数６）のもとで、次式で与えられる評価関数Jを最小化するΔu(k)を求めればよい。次式は、二次計画問題として解かれ、現時点での操作量の偏差ベクトルΔu(k)が求まる。
【００７６】
【数９】

【００７７】
そして、ステップＳ７において、上記ステップＳ６で求めた操作量の偏差Δu(k)を、前時点の操作量u(k-1)に加算することによって、現時点における操作入力を行う操作量u(k)を求める。即ち、次式によって、現時点における流動化空気量、給塵機速度、蒸気弁開度を求める。
【００７８】
【数１０】

【００７９】
そして、ステップＳ８において、上記操作量u(k)を制御対象Ａに入力して、操作対象を操作する。即ち、u(k)に基づいて、流動化空気量、給塵機速度、蒸気弁開度を操作する。
【００８０】
ステップＳ８が終了するとステップＳ１に戻り、以上のステップＳ１からステップＳ８までの処理を制御周期ごと（本実施の形態では３秒）に繰り返す。
【００８１】
次に、図５及び図６に基づいて、本実施の形態に係る制御方法を用いた場合の実験結果について説明する。図５は本実施の形態に係る制御方法を用いた場合の制御結果を示す図である。図６は従来の制御方法を用いた場合の制御結果を示す図である。ここで、制御量は流動床温度（砂層温度）、ボイラドラム圧力、蒸気流量であり、操作量は流動化空気量、給塵機速度、蒸気弁開度（主蒸気調整弁）である。
【００８２】
図６においては、ボイラドラム圧力を一定にするために、フィードバック制御（ＰＩＤ制御）によって蒸気弁開度を操作している。また、流動化空気量および給塵機速度については、操作員（熟練オペレータ）が状況を監視し、知識や経験に基づいて未来の挙動を予測しながら手動で操作している。なお、ここで、流動化空気量や給塵機速度をフィードバック制御手法によって自動操作せず、操作員によって手動操作しているのは、その方がフィードフォワード的な操作が実現できるので、ハンチング等を引き起こすことなく、より速やかに、より安定化できるからである。図５と図６を比べて明らかなように、本実施の形態に係る制御方法によれば、流動床温度とボイラドラム圧力と蒸気流量を安定化することができ、その結果として、溶融炉温度を安定化できていることがわかる。
【００８３】
以上に説明したように、本実施の形態は、モデル予測制御を用いて、多変数モデルを使って制御量の未来の挙動を予測し、操業の制約条件を考慮した上で操作入力を最適化しているため、従来技術にはない下記の利点を有している。
【００８４】
多変数制御系（流動化空気、給塵機速度、蒸気弁開度を入力とし、流動床温度、ボイラドラム圧力、蒸気流量を出力とするモデルを用いた制御系）を構成しているため（ステップＳ３）、操作量（流動化空気、給塵機速度、蒸気弁開度）間の干渉を考慮した上で、熱分解ガス化溶融処理プラント４０全体としてバランスの良い操作を実現できる。また、流動床温度、ボイラドラム圧力、蒸気流量の内、どの制御量を重視するかも、パラメータの数値を変更するだけで、簡単に調整できる。
【００８５】
モデル予測制御を用い、多変数モデル（流動化空気、給塵機速度、蒸気弁開度を入力とし、流動床温度、ボイラドラム圧力、蒸気流量を出力とするモデル）を使って未来の挙動を予測することにより（ステップＳ１〜Ｓ４）、むだ時間を考慮しているため、ＰＩＤのような単純なフィードバック制御に比べて、制御ゲインを高く設定できる。むだ時間が大きく、安定領域の狭い熱分解ガス化溶融炉では、後手後手の制御では制御性能にも限界があり、未来の挙動を予測して早め早めに操作する熟練オペレータ並の操作は実現不可能である。本実施の形態では、むだ時間を考慮した上で操作しているため、熟練オペレータ並の操作が実現できている。
【００８６】
操業上の制約条件を考慮して操作量を最適化しているため（ステップＳ５〜Ｓ７）、熱分解ガス化処理プラント４０の現状に合わせた最適な操作が実現できる。その結果、熱分解ガス化反応を安定して促進し、維持することができる。また、ごみの持つエネルギーをできるだけ有効利用できるような「ぎりぎりの領域」を狙って操業できるため、重油が必要なごみ質の場合にも、その使用量を抑制することができ、ランニングコストが低減できる。
【００８７】
なお、本実施の形態では、モデル予測制御手法を用いているが、むだ時間を補償できる手法であれば、スミス補償など他の手法を用いても同様の効果を得ることができる。そこで、以下、スミス補償を用いた本実施の形態の変形例について簡単に説明する。
【００８８】
例えば、スミス法によるむだ時間補償、特に制御器の保守性を考慮して制御器にＰＩ制御器を用いたスミス補償型ＰＩ制御が考えられる。そこで、スミス補償を付加した閉ループのブロック線図を図７に示す。ブロック線図は、フィードバックコントローラ１０１と、スミス補償器１０２と、制御対象１０３とを有している。フィードバックコントローラ１０１ではＰＩ制御が行われる。また、スミス補償器１０２はモデルＧを用いて未来を予測していることに相当する。また、制御対象１０３は、Ｌｉ秒のむだ時間を含んでいる。なお、本ブロック線図ではフィードバックコントローラ１０１はＰＩ制御としているが、ＰＩ制御でなくてもよい。ここで、Ｇｒを制御対象の真の伝達関数、Ｇを制御器に搭載されるモデルの伝達関数（ノミナルモデル）とすると、制御器からみた制御対象は次式のようになる。
【００８９】
【数１１】

【００９０】
以上から、ＧｒとＧの差が十分小さいとき、制御器から見た制御対象はむだ時間を含まないモデルの伝達関数Ｇとなり、制御ゲインの増加による応答性の向上が期待できる。
【００９１】
以上、本発明の好適な実施の形態について説明したが、本発明は、前記実施の形態に限定されるものではなく、特許請求の範囲に記載した限りにおいてさまざまな設計変更が可能なものである。
【００９２】
本実施の形態では、操作量として流動化空気量と給塵機１３の速度と蒸気弁３２の開度を操作量として用い、制御量として流動床１１の温度とボイラドラム３１の圧力と蒸気流量を用い、さらに、観測量として熱分解ガス化炉の炉内圧力を用いたが、それに限られない。これは、平均的に見れば、実際のごみ供給量は、給塵機１３の速度におよそ比例するが、ごみ供給量の短周期的な変動（極端な場合は「ごみ切れ」や「どか落ち」）は、給塵機１３の速度を一定にしていても起こり得るものであり、より正確な制御量の挙動予測のためには、実際のごみ供給量の変動を反映したモデルを使用する必要がある。そこで、実際のごみ供給量の変動に対して、熱分解ガス化炉１０の炉内圧力は、制御量より早くその影響が現れるため、本実施の形態では、実際のごみ供給量と相関があるものとして、熱分解ガス化炉１０の炉内圧力を制御量の挙動を予測する観測量として用いた。しかし、同様の理由から、熱分解ガス化炉の炉内圧力の他、排ガス流量などでも実際のごみ供給量を把握することができる。また、給塵機への供給電流や誘引送風機の電流でも、ごみ供給量の外乱を検出することができ、実際のごみ供給量を反映した予測をおこなうことができる。
【００９３】
また、熱分解ガス化溶融炉１０では、従来の焼却炉に比べて安定領域が狭いため、制約条件を炉の状態に応じて設定した方が、より安定な制御システムを構築できる。そこで、ごみ質（カロリー）や流動床１１の温度、溶融炉２０の温度の状況に応じて、操業制約条件を設定することによって、より安定な制御システムを構築できる。
【００９４】
なお、制御量として溶融炉２０の温度を用いる場合、溶融炉２０の温度は、熱電対により計測されることが通常であるが、放射温度計や輝度センサなど電磁波を利用するセンサを使用することが望ましい。熱電対による温度計測は、温度変化に対する応答性が悪く、遅れ時間も無視できず、制御性能を悪化させる要因となる。特に溶融炉はいったん温度が低下してスラグの溶融が停止してしまうと再び溶融させるのに手間がかかるだけでなく、最悪の場合出滓口が閉塞する危険性があるため、この計測遅れ時間が致命的な結果を招きかねない。従って、電磁波を利用するセンサを使用すれば、ほとんど計測遅れ時間がないため、制御性能を向上することができ、安定溶融を維持することができる。
【００９５】
また、上述の実施の形態では、操作量不変時の制御量変動分を予測計算しているが、操作量を変えたときの制御量変動分を予測計算してもよい。
【００９６】
更に、上述の実施の形態では、熱分解ガス化溶融処理プラント４０の熱分解ガス化炉１０として、流動床型の熱分解ガス化炉が適用されているがそれに限られない。キルン型など他のタイプの熱分解ガス化炉であってもよい。
例えば、キルン型の熱分解ガス化炉（キルン炉）の場合は、操作量として、キルン炉への給塵量、キルン炉へ吹き込まれる空気量、キルン炉本体の回転数、そして補助バーナーがついている場合にはその供給燃料量などが考えられる。また、制御量として、キルン炉の温度、溶融炉の温度、ボイラが設けられている場合にはボイラから排出される蒸気流量やボイラに備えられたボイラドラムの圧力が考えられる。更に、モデル予測制御手法において、制御量の現時点以降における予測値を求めるに当たって、給塵機への供給電流、キルン炉の炉内圧力、溶融炉から排出される排ガス流量、及び、誘引送風機の電流が考えられる。
【００９７】
【発明の効果】
以上に説明したように、本発明によれば、むだ時間を考慮した制御を行うことにより、制御性能を向上させることができる。
【図面の簡単な説明】
【図１】熱分解ガス化溶融処理プラントの部分概略図。
【図２】本実施の形態に係る制御装置のブロック線図。
【図３】本実施の形態に係る制御方法のフローチャート。
【図４】目標軌道の設定方法を表す一例の図。
【図５】本実施の形態による制御方法を行った場合の実験結果。
【図６】従来の制御方法を行った場合の実験結果。
【図７】スミス補償を付加した閉ループのブロック線図。
【符号の説明】
１ 制御装置
２ 目標軌道生成部
３ 操作量不変時制御量変動分計算部
４ 操作量最適化計算部
５ 制約条件設定部
１０ 熱分解ガス化炉
１１ 流動床
１３ 給塵機
２０ 溶融炉
３０ ボイラ
３１ ボイラドラム
３２ 蒸気弁
４０ 熱分解ガス化溶融処理プラント[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control method and apparatus for a pyrolysis gasification melting treatment plant, and a program. In particular, the present invention relates to a control method and apparatus for a pyrolysis gasification melting treatment plant and a program for controlling the pyrolysis gasification melting treatment plant while predicting future behavior.
[0002]
[Prior art]
In recent years, the amount of heat generated from waste such as municipal waste has been steadily increasing, decreasing due to melting of waste due to tightness of final disposal site capacity, secondary pollution (groundwater contamination), and strengthening of laws and regulations. Consolidation and immobilization are underway. Furthermore, there are many problems required for waste disposal, such as suppression of trace contaminants such as dioxins. Under such circumstances, a pyrolysis gasification melting treatment plant that converts waste gas into pyrolysis gas in a reducing atmosphere, burns the generated combustible gas at a high temperature, and melts the incineration residue has attracted attention. This pyrolysis gasification and melting treatment plant has a fluidized bed gasification furnace in which waste is introduced by a duster and pyrolyzed in a fluidized bed having fluidized particles at the bottom, and discharged from the fluidized bed gasification furnace. And a melting furnace for melting the ash by burning the pyrolysis gas.
[0003]
The pyrolysis gasification melting treatment plant has the following features.
(1) It becomes possible to melt ash by using the energy of waste, and to reduce the volume of incineration residues and to recycle them.
(2) Valuable metals can be recovered by low-temperature pyrolysis.
(3) Since the low air ratio is possible, the apparatus can be made compact.
(4) High temperature combustion in a melting furnace makes it possible to suppress trace harmful substances such as dioxins.
[0004]
The main operation amount of the pyrolysis gasification melting treatment plant is, for example, a dust supply amount (dust supply speed) that is an amount of waste input and a flow that is an amount of air fed into the fluidized bed of the gasification melting furnace. The amount of air is mentioned. In the prior art, the operation of these operation amounts is basically performed manually by an operator or in combination with a single control loop. In addition, in a plant where a waste heat boiler is installed after the pyrolysis gasification and melting treatment plant and heat recovery is performed, the steam valve pressure on the boiler output side is conventionally adjusted, and the boiler drum pressure is automatically controlled. It was constant. Then, it is conceivable to stabilize the temperature near the outlet of the fluidized bed gasification furnace or the pyrolysis gasification melting treatment plant, the temperature of the melting furnace, or the steam flow rate from the boiler by these methods. Further, in JP 2001-182925, as a control method and apparatus for the above-mentioned pyrolysis gasification melting treatment plant, the fluidized bed temperature is controlled by the amount of fluidized air, and the melting furnace temperature or the steam flow rate is set to the amount of dust supply. In the control system controlled by the control, a control method is disclosed in which interference with the fluidized bed temperature due to the operation of the dust supply amount is compensated by a non-interferor.
[0005]
[Problem to be Solved by the Invention]
However, in the pyrolysis gasification melting treatment plant, the fluidized bed is maintained in a reducing atmosphere, and the pyrolysis reaction is based on a delicate balance between the amount of dust supply and the amount of fluidized air. That is, compared to a fluidized bed incinerator that incinerates garbage in an oxidizing atmosphere, the pyrolysis gasification and melting treatment plant has a higher sensitivity of the fluidized bed temperature to the dust feeder and the amount of fluidized air, and the stable region is narrower. It is a difficult control target. For example, in order to slow down the thermal decomposition reaction and absorb the influence of disturbance of the dust supply amount, it is necessary to lower the fluidized bed temperature. There is a danger that the temperature will drop rapidly, resulting in stalling. Further, in order to utilize as much energy as possible in the high-temperature combustion / melting reaction in the melting furnace, it is necessary to keep the air ratio low in the fluidized bed gasification furnace and suppress the combustion amount. Thus, in order to stably promote and maintain the pyrolysis gasification reaction, there is a problem that the control operation amount must be determined while satisfying various constraints.
[0006]
Also, in pyrolysis gasification and melting processing plant, it cannot be ignored until the fluidized bed temperature and melting furnace temperature (steam flow rate in the case of boiler attachment) fluctuate after changing the dust supply amount and flowing air amount. There is a dead time, and feedback control logic such as PID control has a problem that hunting occurs when the gain is increased, and response characteristics deteriorate when the gain is decreased. Furthermore, in the control method and control apparatus for a pyrolysis gasification and melting treatment plant disclosed in Japanese Patent Application Laid-Open No. 2001-182925, the influence of interference from the amount of dust supply to the fluidized bed temperature is compensated by a non-interferor. However, since the effect of dead time is not taken into account, there is a problem that the actual control performance is limited. Further, there is a problem that it is impossible to optimize the operation amount while satisfying the operational constraints.
[0007]
One object of the present invention is to provide a control method and apparatus for a pyrolysis gasification and melting treatment plant and a program capable of improving the control performance in consideration of dead time.
[0008]
A further object of the present invention is to provide a control method and apparatus for a pyrolysis gasification melting treatment plant and a program capable of improving control performance while satisfying operational constraints.
[0009]
[Means for Solving the Problems]
  To solve the above-mentioned problems, the present inventionHeat ofControl method for cracked gasification and melting treatment plantThe first feature inIs included in the pyrolysis gasification furnace that pyrolyzes the waste introduced by the dust feeder to generate pyrolysis gas, and the pyrolysis gas discharged from the pyrolysis gasification furnace is combusted. In the control method of the pyrolysis gasification melting treatment plant having a melting furnace for melting ash, the dead time based on the current measured value and the predicted value after the present time of the control amount related to the pyrolysis gasification melting treatment plant The amount of operation related to the pyrolysis gasification and melting treatment plant is optimized and determined in consideration of the operational constraints of the pyrolysis gasification and melting treatment plantInThe
[0010]
  Also,The present inventionHeat ofControl equipment for cracked gasification and melting treatment plantThe first feature inIs included in the pyrolysis gasification furnace that pyrolyzes the waste introduced by the dust feeder to generate pyrolysis gas, and the pyrolysis gas discharged from the pyrolysis gasification furnace is combusted. In a control apparatus for a pyrolysis gasification melting treatment plant having a melting furnace for melting ash, a dead time based on a measured value and a predicted value after the present time of a control amount related to the pyrolysis gasification melting treatment plant The amount of operation related to the pyrolysis gasification and melting treatment plant is optimized and determined in consideration of the operational constraints of the pyrolysis gasification and melting treatment plantInThe
[0012]
  According to these configurations, the operation related to the pyrolysis gasification melting treatment plant is compensated so that the dead time is compensated based on the current measured value of the control amount related to the pyrolysis gasification melting treatment plant and the predicted value after the current time. Since the dead time is taken into account by determining the amount, the control gain can be set higher than in simple feedback control such as PID, and the followability to the target value can be improved. . In particular, the pyrolysis gasification and melting treatment plant has a large dead time and a narrow stable region. However, it is possible to realize an operation equivalent to a skilled operator by operating early by predicting future behavior.In addition, since the amount of operation is optimized in consideration of operational constraints, it is possible to realize the optimum operation according to the plant, and to stably promote and maintain the pyrolysis gasification reaction. it can.
[0013]
  The present inventionHeat ofControl method for cracked gasification and melting treatment plantSecond feature inIs included in the pyrolysis gasification furnace that pyrolyzes the waste introduced by the dust feeder to generate pyrolysis gas, and the pyrolysis gas discharged from the pyrolysis gasification furnace is combusted. In a control method for a pyrolysis gasification melting treatment plant having a melting furnace for melting ash, the control amount of the control amount is calculated based on a current measurement value and a target value after the present time of the control amount relating to the pyrolysis gasification melting treatment plant. A step of determining a target trajectory; a step of obtaining a predicted value of the control amount after the current time; a step of obtaining a deviation amount between the target trajectory and the predicted value; and the pyrolysis gas so that the deviation amount is compensated And a step of optimizing and determining an operation amount related to the gasification / melting treatment plant in consideration of operating constraints of the pyrolysis gasification / melting treatment plant. That.
[0014]
  Also,The present inventionHeat ofControl equipment for cracked gasification and melting treatment plantSecond feature inIs included in the pyrolysis gasification furnace that pyrolyzes the waste introduced by the dust feeder to generate pyrolysis gas, and the pyrolysis gas discharged from the pyrolysis gasification furnace is combusted. In a control apparatus for a pyrolysis gasification melting treatment plant having a melting furnace for melting ash, from a measured value at the present time and a target value after the present time of a control amount relating to the pyrolysis gasification melting treatment plant, Means for determining a target trajectory; means for determining a predicted value of the control amount after the current time; means for determining a deviation amount between the target trajectory and the predicted value; and the pyrolysis gas so that the deviation amount is compensated. And a means for optimizing and determining an operation amount related to the gasification / melting treatment plant in consideration of operating constraints of the pyrolysis gasification / melting treatment plant.
[0016]
  According to these configurations, using the model predictive control for the pyrolysis gasification melting treatment plant, the target trajectory determined from the measured value of the current control amount and the target value after the current time, and the operation amount at the current time are calculated. Since the dead time is taken into account by determining the operation amount so as to approach the target trajectory based on the fluctuation of the control amount predicted when fixed, the simple feedback control like PID Compared to the above, the control gain can be set higher, and the followability to the target value can be improved. In particular, the pyrolysis gasification and melting treatment plant has a large dead time and a narrow stable region. However, it is possible to realize an operation equivalent to a skilled operator by operating early by predicting future behavior. The target value after the present time is intended to set the target trajectory in accordance with the target value when it is known in advance that the target value will change at a certain time in the future.In addition, since the amount of operation is optimized in consideration of operational constraints, it is possible to realize the optimum operation according to the plant, and to stably promote and maintain the pyrolysis gasification reaction. it can.
[0025]
  In the present invention, in obtaining the predicted value of the control amount after the present time, the supply current to the dust feeder, the furnace pressure of the pyrolysis gasifier, the exhaust gas flow rate discharged from the melting furnace, and the attraction Use at least one of the blower currentsYes.An induction fan (IDF) is a fan for attracting exhaust gas in the furnace and releasing it from the chimney. When the pressure in the furnace increases, the rotational pressure is increased and a large amount of gas is attracted. It operates to maintain (negative pressure).
[0026]
According to this configuration, since the control current is predicted as at least one of the supply current to the dust feeder, the furnace pressure of the pyrolysis gasification furnace, the exhaust gas flow rate, and the induction blower current, the actual waste Therefore, it is possible to make a prediction reflecting the actual dust supply amount. Explaining in detail, the amount of dust supply is generally proportional to the rotational speed of the dust supply material, but there are many variations in the properties of the dust, and even if the dust supply speed is constant, the actual amount of dust supply varies. . When the quality of the garbage is poor, there is a case where the garbage is thrown in at once, which is called “slow dropping”. Therefore, accurate prediction cannot be made only with the dust feeder speed, and accurate prediction can be made by using the above data reflecting these dust supply disturbances.
[0027]
  In the present invention, at least one of the manipulated variable and the controlled variable may be multivariable.Yes.
[0028]
According to this configuration, since the multivariable control system is configured by controlling at least one of the operation amount and the control amount as a plurality of variables, the balance of the entire plant is considered in consideration of interference between the operation amounts. Good operation can be realized. Further, the control amount to be emphasized can be easily adjusted by changing the control parameter.
[0029]
  In the present invention, the pyrolysis gasification furnace is provided with a fluidized bed at the bottom, and the operation amount is at least one of the amount of air blown into the fluidized bed and the amount of dust supplied to the pyrolysis gasification furnace. Operate oneYes.
[0030]
According to this configuration, by manipulating at least the amount of air blown into the fluidized bed or the amount of dust supplied to the pyrolysis gasification furnace, the operation of the amount of air blown into the fluidized bed and the amount of dust supplied to the pyrolysis gasification furnace A well-balanced operation as a whole plant can be realized in consideration of interference between quantities. Moreover, the important control amount can be easily adjusted by changing the numerical value of the amount of air blown into the fluidized bed or the amount of dust supplied to the pyrolysis gasification furnace.
[0031]
  In the present invention, the amount of air blown into the fluidized bed and the amount of dust supplied to the pyrolysis gasification furnace are manipulated as the manipulated variable, and the temperature of the fluidized bed and the temperature of the melting furnace are manipulated as the controlled variable. ControlYes.
[0032]
According to this configuration, the amount of air blown into the fluidized bed and the pyrolysis gasifier are controlled by operating at least the amount of air blown into the fluidized bed or the amount of dust supplied and controlling at least the fluidized bed temperature or the temperature of the melting furnace. Considering the interference between the operation amounts of the dust supply amount, it is possible to realize a balanced operation as a whole plant. In addition, by changing the numerical value of the amount of air blown into the fluidized bed or the amount of dust supplied to the pyrolysis gasifier, the controlled amount of fluidized bed temperature or melting furnace temperature can be easily adjusted. be able to.
[0033]
  In the present invention, the pyrolysis gasification melting treatment plant is the pyrolysis gasification furnace.as well asIt further has a boiler that recovers heat generated in the melting furnace and generates steam, and operates the amount of air blown into the fluidized bed and the amount of dust supplied to the pyrolysis gasification furnace as the operation amount. Then, as the control amount, control the temperature of the fluidized bed and the flow rate of steam discharged from the boiler.Yes.
[0034]
  According to this configuration, there is a correlation between the temperature of the melting furnace and the flow rate of steam discharged from the boiler, so by controlling the flow rate of steam discharged from the boiler instead of the temperature of the melting furnace,In consideration of the interference between the amount of air blown into the fluidized bed and the amount of operation of the amount of dust supplied to the pyrolysis gasifier, a balanced operation can be realized as a whole plant. In addition, by changing the numerical value of the amount of air blown into the fluidized bed or the amount of dust supplied to the pyrolysis gasifier, the controlled amount of fluidized bed temperature or melting furnace temperature can be easily adjusted. be able to.
[0035]
  In the present invention, the pyrolysis gasification melting treatment plant is the pyrolysis gasification furnace.as well asIt further has a boiler that recovers heat generated in the melting furnace and generates steam, and as the operation amount, the amount of air blown into the fluidized bed, the amount of dust supplied to the pyrolysis gasification furnace, and the Operate the opening of the steam valve provided in the boiler, and control the temperature of the fluidized bed, the flow rate of steam discharged from the boiler, and the pressure of the boiler drum provided in the boiler as the controlled variable.Yes.
[0036]
According to this configuration, the amount of air blown into the fluidized bed, the amount of dust supplied to the pyrolysis gasifier, and the opening degree of the steam valve provided in the boiler are operated, and the fluidized bed temperature and the boiler are discharged. By controlling the flow rate of steam and the pressure of the boiler drum provided in the boiler, the amount of air blown into the fluidized bed, the amount of dust supplied to the pyrolysis gasifier, and the opening of the steam valve provided in the boiler In consideration of the interference between the operation amounts, it is possible to realize a balanced operation as the whole plant. In addition, by changing the control parameters for the amount of air blown into the fluidized bed, the amount of dust supplied to the pyrolysis gasifier, and the opening degree of the steam valve provided in the boiler, the temperature of the fluidized bed and the boiler The amount of steam discharged from the boiler and the control amount of the pressure of the boiler drum provided in the boiler can be easily adjusted. Furthermore, it is possible to stabilize the flow rate of the steam discharged from the boiler by operating the opening of the steam valve provided in the boiler and controlling the pressure of the boiler drum provided in the boiler.
[0041]
  The operational constraints may be set according to the state of the pyrolysis gasification melt treatment plant.Yes.
[0042]
  According to this configuration, operational constraints are set according to the conditions of the pyrolysis gasification and melting plant.,More optimal operation according to the current state of the runt can be realized, and the pyrolysis gasification reaction can be stably promoted and maintained. In addition, since the pyrolysis gasification melting furnace has a narrower stability region than conventional incinerators, a more stable control system can be constructed by setting the constraint conditions according to the state of the plant. In addition, since it is possible to perform the operation that makes the most efficient use of the energy of waste, it is possible to reduce the amount of heavy oil used, for example, even when it is necessary to use heavy oil due to the nature of the waste. This can reduce the running cost of the plant.
[0043]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
[0044]
First, a control method and apparatus according to an embodiment of the present invention and a configuration of a pyrolysis gasification melting treatment plant to which a program is applied will be described with reference to FIG. FIG. 1 shows a partial schematic diagram of a pyrolysis gasification melting treatment plant.
[0045]
As shown in FIG. 1, the pyrolysis gasification melting treatment plant 40 includes a pyrolysis gasification furnace 10, a melting furnace 20, and a boiler 30.
[0046]
The pyrolysis gasification furnace 10 is provided with a hopper 12 for introducing waste (industry waste, industrial waste, etc.) that is an incinerator, and the waste introduced into the hopper 12 is supplied with a dust feeder 13. Is supplied to a fluidized bed 11 to be described later. Note that the amount of waste (dust supply amount) supplied by the dust supply device 13 can be increased or decreased by adjusting the rotational speed of the dust supply device 13. The pyrolysis gasification furnace 10 is provided with a fluidized bed 11 made of fluidized particles (for example, sand) at the bottom. Fluidized air is blown from the lower part of the fluidized bed 11 by a blower (not shown), and the fluidized particles in the fluidized bed 11 and the waste supplied by the dust feeder 13 are fluidized and stirred. In this pyrolysis gasification furnace 10, the temperature of the sand bed of the fluidized bed 11 is less than the melting point (600 ° C.) of aluminum, and metals such as iron and aluminum are recovered in an unoxidized state. It is driven to become. The waste is pyrolyzed in a reducing atmosphere having an air ratio of about 0.2 to 0.3 in the fluidized bed 11 to become pyrolysis gas (combustible gas) and unburned solids (char, ash, etc.). Then, it goes out to the melting furnace 20 mentioned later.
[0047]
The melting furnace 20 burns the pyrolysis gas and unburned solid content generated in the pyrolysis gasification furnace 10 at a high temperature of about 1300 to 1400 ° C. Further, in the melting furnace 20, the part following the pyrolysis gasification furnace 10 is a swirling flow melting furnace 21, and combustion air, which will be described later, is swirled strongly as indicated by an arrow in the figure. Unburned pyrolysis gas is burned at a high temperature by the combustion air. The combustion air is preheated by an air preheater (not shown) and supplied from the supply port 22. If the sensible heat of the waste is insufficient, heavy oil is used in addition to the combustion air. The ash melts, slag is generated, and dioxins are decomposed. The molten slag is used as a useful resource by being recovered from the slag flow outlet 23 to the outside of the furnace.
[0048]
The boiler 30 is attached to the pyrolysis gasification furnace 10 and the melting furnace 20 and collects heat generated in the gasification and melting process. The boiler 30 includes a boiler drum 31 that evaporates water using heat generated in the gasification and melting process, and a steam valve 32 that adjusts the pressure of the boiler drum 31 and the flow rate of steam discharged from the boiler drum 31. ing. The energy of the steam generated in the boiler 30 is converted into electric energy by a generator (not shown) and recovered as surplus power or facility power. Further, on the downstream side of the boiler 30, a gas cooling device, an exhaust gas treatment device (such as a bag filter), an induction blower, and a chimney (not shown) are sequentially installed. Here, the induction blower (IDF) is a blower for attracting exhaust gas in the furnace and releasing it from the chimney. When the pressure in the furnace increases, the rotational pressure is increased to attract a large amount of gas. Is kept constant (negative pressure).
[0049]
Next, a control device according to an embodiment of the present invention will be described with reference to FIG. FIG. 2 shows a block diagram of the control device according to the present embodiment. In the present embodiment, a model predictive control method is used as the control method.
[0050]
The control device 1 includes a target trajectory generation unit 2, an operation amount invariable control amount variation calculation unit 3, an operation amount optimization calculation unit 4, a constraint condition setting unit 5, a control amount difference calculation unit 6, and an operation amount The control amount deviation calculating part 7 at the time of a quantity invariant is provided.
[0051]
The target trajectory generation unit 2 sets a target trajectory yr (k + i) based on the target value r (k + i) of the control amount and the actually measured value y (k) of the control amount.
[0052]
The manipulated variable invariable control variable fluctuation calculation unit 3 changes the manipulated variable thereafter from the history of the measured variable y (k), the manipulated input u (k), and the other observed variable w (k) of the controlled object. If not, the control amount variation Δy0 (k + i) is calculated. In calculating Δy0 (k + i), u (k) depends on the type of model used (ARX model, step response model, simulator made up of programs, etc.) and the number of operation inputs (single input or multiple inputs). , Y (k) is not required, w (k) is a model that estimates the behavior after the current time, and other functions that estimate the influence of disturbance may be included. . In the present embodiment, the value of the pressure in the pyrolysis gasification furnace 10 is used as w (k).
[0053]
On the other hand, the constraint condition setting unit 5 sets constraint conditions according to the situation of the pyrolysis gasification melting treatment plant 40. The constraints include, for example, the control input and control amount upper and lower limits, the control input fluctuation amount restriction, the outlet temperature of the pyrolysis gasification furnace 10 and the melting furnace 20, but not the direct control amount. There are certain restrictions and the like, and any of them can be expressed directly or indirectly as a constraint condition of an operation input. In addition, by changing these constraints depending on the target throughput, waste quality (garbage quality), fluidized bed temperature, molten state (melting furnace temperature), boiler drum 31 pressure, etc., pyrolysis gasification melting treatment Operation according to the situation of the plant 40 becomes possible, and more stable automatic operation can be realized.
[0054]
Further, the control amount difference calculation unit 6 is a difference yr (k + i) from the actual control value y (k) when compared with the target track yr (k + i) set by the target track generation unit 2. -Calculate y (k).
[0055]
The manipulated variable invariable controlled variable deviation calculating unit 7 calculates the difference between the target trajectory yr (k + i) set by the target trajectory generating unit 2 obtained from the controlled variable difference calculating unit 6 and the actual measured value y (k) of the controlled variable. From yr (k + i) -y (k) and the amount of change Δy0 (k + i) of the controlled variable when the manipulated variable is not changed after being obtained by the manipulated variable invariable controlled variable variation calculation unit 3 Then, the difference Δye (k + i) in how much the controlled variable deviates from the target trajectory when the manipulated variable remains unchanged is calculated.
[0056]
Then, in the manipulated variable determining unit 4, the difference Δye (k + i) in how much the controlled variable deviates from the target trajectory when the manipulated variable remains unchanged calculated by the manipulated variable invariable controlled variable deviation calculating unit 7 and the constraint condition Based on the constraint conditions, model, and adjustment parameters set by the setting unit 5, the control input deviation amount Δu (k) for compensating Δye (k + i) is optimized. By adding this Δu (k) to the manipulated variable u (k−1) of the previous control period, the control input u (k) to be input to the controlled object A is obtained.
[0057]
Next, the control method by embodiment of this invention is demonstrated based on the flowchart of FIG. FIG. 3 shows a flowchart of the control method according to the present embodiment. In the present embodiment, a model predictive control method is used as a control method as in the above-described control device.
[0058]
First, in step S1, a control value target value r (k + i) is set. Here, the target value r (k + i) is the temperature of the fluidized bed 11 (hereinafter referred to as “fluidized bed temperature”) and the pressure of the boiler drum 31 provided in the boiler 30 (hereinafter referred to as “boiler drum pressure”). And a vector having each target value of the steam flow rate (hereinafter referred to as “steam flow rate”) discharged from the boiler 30 as an element.
[0059]
Next, in step S2, the target trajectory generation unit 2 sets a target trajectory yr (k + i) based on the control value target value r (k + i) and the actual measurement value y (k). As a method for setting the target trajectory yr (k + i), for example, there is a method shown in FIG. This is set as shown in the following equation, and approaches y (k + i) from y (k) at a constant rate. If the matrix C of the following equation is a 3 × 3 zero matrix, yr (k + i) matches r (k + i) itself.
[0060]
[Expression 1]

[0061]
Next, in step S3, the manipulated variable invariable controlled variable variation calculation unit 3 calculates the controlled variable variation Δy0 (k + i) when the manipulated variable is unchanged using the model. Here, the model refers to the amount of air blown into the fluidized bed 11 (hereinafter referred to as “fluidized air amount”), the dust supply speed (hereinafter referred to as “dust supply”) as the amount of dust supplied to the pyrolysis gasifier 10. ), The opening of the steam valve 32 provided in the boiler 30 (hereinafter referred to as “steam valve opening”) as input, and the fluidized bed temperature, boiler drum pressure, and steam flow rate as output. The model includes the pressure inside the pyrolysis gasifier as an observation quantity, and is expressed by the following equation.
[0062]
[Expression 2]

[0063]
Here, Δy0 (k + i) is a change amount of the control amount when the operation amount is not changed in the future. Therefore, Δy0 (k + i) is obtained by the following equation using the model represented by the above equation (Equation 2). In the following equation, the observed pressure in the pyrolysis gasification furnace and the value after the current time are required, but the value after this time is estimated using another model. ing.
[0064]
[Equation 3]

[0065]
In step S4, the control amount difference calculation unit 6 and the manipulated variable invariable control amount deviation calculation unit 7 change the target trajectory yr (k + i) obtained in step S2 and the future operation amount obtained in step S3. If the control amount is not changed Δy0 (k + i), and the actual measured value y (k) of the current controlled variable (a vector having the measured values of fluidized bed temperature, boiler drum pressure, and steam flow as elements) Thus, the deviation Δye (k + i) between the controlled variable and the target trajectory when the manipulated variable is not changed is calculated by the following equation.
[0066]
[Expression 4]

[0067]
Next, in step S5, the constraint condition setting unit 5 sets a constraint condition for the operation input Δu (k + i). For example, the upper and lower limit constraints of the operation input and the upper and lower limit constraints of the fluctuation range are expressed by the following equations.
[0068]
[Equation 5]

[0069]
In addition, since the constraint condition related to the controlled variable is also expressed as a function of the manipulated variable, all of these constraint conditions can be reduced to the form of the following equation.
[0070]
[Formula 6]

[0071]
Then, in step S6, the manipulated variable optimization calculation unit 4 uses the model to calculate the deviation input Δu (k) for compensating for the deviation Δye (k + i) obtained in step S4 in a future fixed interval. Ask. Here, the model is a model in which the fluidized air amount, the dust feeder speed, and the steam valve opening are input, and the fluidized bed temperature, boiler drum pressure, and steam flow rate are output, and is expressed by the following equation.
[0072]
[Expression 7]

[0073]
When a part Δy + (k + i) representing the influence of the operation input after the present time on the control amount is extracted from the model represented by the above equation (Equation 7), the following equation is obtained.
[0074]
[Equation 8]

[0075]
The purpose here is to obtain a deviation input Δu (k) for compensating for the deviation Δye (k + i). For this purpose, a deviation input Δu (k) may be obtained such that Δye (k + i) and Δy + (k + i) match as much as possible in a certain future section. Specifically, Δu (k) that minimizes the evaluation function J given by the following equation may be obtained under the above-described constraint condition (Equation 6). The following equation is solved as a quadratic programming problem, and a deviation vector Δu (k) of the operation amount at the present time is obtained.
[0076]
[Equation 9]

[0077]
In step S7, the operation amount u (k) for performing the operation input at the present time is obtained by adding the deviation Δu (k) of the operation amount obtained in step S6 to the operation amount u (k-1) at the previous time point. ) That is, the fluidized air amount, the dust feeder speed, and the steam valve opening degree at the present time are obtained by the following equations.
[0078]
[Expression 10]

[0079]
In step S8, the operation amount u (k) is input to the control object A to operate the operation object. That is, the fluidized air amount, the dust feeder speed, and the steam valve opening are manipulated based on u (k).
[0080]
When step S8 ends, the process returns to step S1, and the above processing from step S1 to step S8 is repeated every control cycle (3 seconds in the present embodiment).
[0081]
  Next, based on FIG.5 and FIG.6, the experimental result at the time of using the control method which concerns on this Embodiment is demonstrated. FIG. 5 is a diagram showing a control result when the control method according to the present embodiment is used. FIG. 6 is a diagram showing a control result when the conventional control method is used. Here, the controlled variable is fluidized bed temperature (sand layer temperature), boiler drum pressure, steam flow rate, and the manipulated variable is fluidized air volume, dust feeder speed, steam valve opening.(Main steam control valve)It is.
[0082]
In FIG. 6, in order to keep the boiler drum pressure constant, the steam valve opening is operated by feedback control (PID control). The fluidized air amount and the dust feeder speed are manually operated by an operator (skilled operator) monitoring the situation and predicting future behavior based on knowledge and experience. Here, the fluidized air amount and the dust feeder speed are not automatically operated by the feedback control method, but are manually operated by the operator, so that the feedforward operation can be realized, so hunting, etc. This is because it can be stabilized more quickly without causing any trouble. As apparent from the comparison between FIG. 5 and FIG. 6, according to the control method according to the present embodiment, the fluidized bed temperature, the boiler drum pressure, and the steam flow rate can be stabilized. It can be seen that
[0083]
As described above, the present embodiment uses model predictive control to predict the future behavior of the controlled variable using a multivariable model, and optimizes the operation input after taking into account operational constraints. Therefore, it has the following advantages not found in the prior art.
[0084]
Because it constitutes a multi-variable control system (a control system using a model with fluidized air, dust collector speed, steam valve opening as input, fluidized bed temperature, boiler drum pressure, steam flow as output) ( In consideration of interference among the operation amounts (fluidized air, dust feeder speed, steam valve opening) in step S3), a well-balanced operation can be realized as the entire pyrolysis gasification melting treatment plant 40. In addition, it can be easily adjusted only by changing the numerical value of the parameter which control amount is important among the fluidized bed temperature, boiler drum pressure, and steam flow rate.
[0085]
Using model predictive control, multi-variable models (models with fluidized air, dust feeder speed, steam valve opening as inputs, fluidized bed temperature, boiler drum pressure, steam flow as outputs) are used to determine future behavior. By predicting (steps S1 to S4), the dead time is taken into consideration, so that the control gain can be set higher than that of simple feedback control such as PID. In a pyrolysis gasification and melting furnace with a large dead time and a narrow stable region, control of the rear and rear hands is limited in control performance, and it is impossible to predict the behavior of the future and to operate the same as an experienced operator as soon as possible. Is possible. In this embodiment, since the operation is performed in consideration of the dead time, an operation similar to an experienced operator can be realized.
[0086]
Since the operation amount is optimized in consideration of the operational constraints (steps S5 to S7), the optimum operation in accordance with the current state of the pyrolysis gasification processing plant 40 can be realized. As a result, the pyrolysis gasification reaction can be stably promoted and maintained. In addition, because it can be operated aiming at the “bare area” where the energy of the waste can be used as effectively as possible, even when the waste oil quality requires heavy oil, the amount used can be reduced, and the running cost can be reduced. .
[0087]
Although the model predictive control method is used in the present embodiment, the same effect can be obtained by using other methods such as Smith compensation as long as the method can compensate for the dead time. Therefore, a modification of the present embodiment using Smith compensation will be briefly described below.
[0088]
For example, dead time compensation by the Smith method, particularly Smith compensated PI control using a PI controller as a controller in consideration of maintainability of the controller can be considered. FIG. 7 shows a closed loop block diagram to which Smith compensation is added. The block diagram includes a feedback controller 101, a Smith compensator 102, and a control target 103. The feedback controller 101 performs PI control. Further, the Smith compensator 102 corresponds to predicting the future using the model G. Further, the control object 103 includes a dead time of Li seconds. In this block diagram, the feedback controller 101 uses PI control, but it does not have to be PI control. Here, when Gr is a true transfer function of a control object and G is a transfer function (nominal model) of a model mounted on the controller, the control object viewed from the controller is as follows.
[0089]
## EQU11 ##

[0090]
From the above, when the difference between Gr and G is sufficiently small, the control target viewed from the controller becomes the transfer function G of the model that does not include the dead time, and an improvement in responsiveness due to an increase in control gain can be expected.
[0091]
The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various design changes can be made as long as they are described in the claims. .
[0092]
In the present embodiment, the fluidized air amount, the speed of the dust feeder 13 and the opening of the steam valve 32 are used as the operation amount as the operation amount, and the temperature of the fluidized bed 11, the pressure of the boiler drum 31 and the steam flow rate as the control amount. In addition, the in-furnace pressure of the pyrolysis gasifier was used as an observation amount, but is not limited thereto. This is because, on average, the actual amount of waste supply is roughly proportional to the speed of the dust feeder 13, but short-term fluctuations in the amount of waste supply (in extreme cases, "out of garbage" ") Can occur even when the speed of the dust feeder 13 is kept constant, and in order to predict the behavior of the control amount more accurately, it is necessary to use a model that reflects fluctuations in the actual waste supply amount. There is. In view of this, since the influence of the pressure in the pyrolysis gasification furnace 10 on the fluctuation of the actual waste supply amount appears earlier than the control amount, in this embodiment, there is a correlation with the actual waste supply amount. As an example, the pressure inside the pyrolysis gasification furnace 10 was used as an observation amount for predicting the behavior of the control amount. However, for the same reason, the actual waste supply amount can be grasped not only by the furnace pressure of the pyrolysis gasifier but also by the exhaust gas flow rate. In addition, it is possible to detect a disturbance in the amount of dust supply even with the current supplied to the dust feeder and the current of the induction blower, and to make a prediction reflecting the actual amount of dust supply.
[0093]
In the pyrolysis gasification melting furnace 10, since the stable region is narrower than that of the conventional incinerator, a more stable control system can be constructed by setting the constraint conditions according to the state of the furnace. Therefore, a more stable control system can be constructed by setting operation restriction conditions according to the state of waste quality (calories), the temperature of the fluidized bed 11, and the temperature of the melting furnace 20.
[0094]
When the temperature of the melting furnace 20 is used as a control amount, the temperature of the melting furnace 20 is usually measured by a thermocouple, but a sensor using electromagnetic waves such as a radiation thermometer or a luminance sensor should be used. Is desirable. Temperature measurement using a thermocouple has poor responsiveness to temperature changes, the delay time cannot be ignored, and causes a deterioration in control performance. In particular, if the melting furnace is once cooled down and melting of the slag stops, it takes time to melt again, and in the worst case there is a risk that the tap will close, so this measurement delay time Can have fatal consequences. Therefore, if a sensor using electromagnetic waves is used, there is almost no measurement delay time, so that the control performance can be improved and stable melting can be maintained.
[0095]
In the above-described embodiment, the control amount variation when the operation amount is unchanged is predicted and calculated. However, the control amount variation when the operation amount is changed may be predicted and calculated.
[0096]
Furthermore, in the above-described embodiment, a fluidized bed pyrolysis gasification furnace is applied as the pyrolysis gasification furnace 10 of the pyrolysis gasification melting treatment plant 40, but is not limited thereto. Other types of pyrolysis gasification furnaces such as a kiln type may be used.
For example, in the case of a kiln-type pyrolysis gasification furnace (kiln furnace), the operation amount includes the amount of dust supplied to the kiln furnace, the amount of air blown into the kiln furnace, the rotational speed of the kiln furnace body, and an auxiliary burner. If so, the amount of fuel supplied can be considered. Further, as the controlled variable, the temperature of the kiln furnace, the temperature of the melting furnace, and the flow rate of steam discharged from the boiler and the pressure of the boiler drum provided in the boiler are conceivable. Furthermore, in the model predictive control method, in obtaining the predicted value of the control amount after the present time, the supply current to the dust feeder, the furnace pressure of the kiln furnace, the exhaust gas flow rate discharged from the melting furnace, and the current of the induction fan Can be considered.
[0097]
【The invention's effect】
As described above, according to the present invention, control performance can be improved by performing control in consideration of dead time.
[Brief description of the drawings]
FIG. 1 is a partial schematic view of a pyrolysis gasification melting treatment plant.
FIG. 2 is a block diagram of a control device according to the present embodiment.
FIG. 3 is a flowchart of a control method according to the present embodiment.
FIG. 4 is a diagram illustrating an example of a method for setting a target trajectory.
FIG. 5 shows an experimental result when the control method according to the present embodiment is performed.
FIG. 6 shows an experimental result when a conventional control method is performed.
FIG. 7 is a closed loop block diagram with Smith compensation added.
[Explanation of symbols]
1 Control device
2 Target trajectory generator
3 Control amount fluctuation calculation section when manipulated variable does not change
4 Operation amount optimization calculator
5 Restriction condition setting part
10 Pyrolysis gasifier
11 Fluidized bed
13 Dust feeder
20 Melting furnace
30 boiler
31 Boiler drum
32 Steam valve
40 Pyrolysis gasification melting treatment plant

Claims (20)

A pyrolysis gasification furnace that is provided with a fluidized bed at the bottom and pyrolyzes the waste introduced by the dust feeder to generate pyrolysis gas, and combusts the pyrolysis gas discharged from the pyrolysis gasification furnace And a control method for a pyrolysis gasification melting treatment plant having a melting furnace for melting ash contained therein,
Obtaining a predicted value of the control amount related to the pyrolysis gasification melting treatment plant after the present time, and based on the predicted value and the actual measurement value of the control amount at the present time, the pyrolysis gasification so that the dead time is compensated The operation amount related to the melting treatment plant is considered in consideration of the operational constraints of the pyrolysis gasification melting treatment plant, and the constraint conditions are the target treatment amount, the quality of the waste, the temperature of the fluidized bed, and the melting A control method for a pyrolysis gasification and melting treatment plant, wherein the control method is determined and optimized according to at least one of furnace temperatures . A pyrolysis gasification furnace that is provided with a fluidized bed at the bottom and pyrolyzes the waste introduced by the dust feeder to generate pyrolysis gas, and combusts the pyrolysis gas discharged from the pyrolysis gasification furnace And a control method for a pyrolysis gasification melting treatment plant having a melting furnace for melting ash contained therein,
A step of determining a target trajectory of the control amount from a measured value at the present time and a target value after the present time of the control amount relating to the pyrolysis gasification melting treatment plant;
Obtaining a predicted value of the control amount after the current time;
Obtaining a deviation amount between the target trajectory and the predicted value;
The operation amount related to the pyrolysis gasification and melting treatment plant so that the deviation amount is compensated, the constraint condition in operation of the pyrolysis gasification and melting treatment plant is taken into account , and the constraint condition is set as the target processing amount, A pyrolysis gasification melting process characterized by having a step of optimizing and determining after setting according to at least one of the quality of waste, the temperature of the fluidized bed, and the temperature of the melting furnace Plant control method. A pyrolysis gasification furnace that pyrolyzes the waste introduced by the dust feeder to generate pyrolysis gas, and burns the pyrolysis gas discharged from the pyrolysis gasification furnace and removes ash contained in the pyrolysis gasification furnace. In a control method of a pyrolysis gasification melting treatment plant having a melting furnace for melting,
Using at least the furnace pressure of the pyrolysis gasification furnace, obtain a predicted value of the control amount related to the pyrolysis gasification melting treatment plant from the present time onward, and based on the predicted value and the actual measurement value of the control amount at the present time The operation amount related to the pyrolysis gasification and melting treatment plant is optimized and determined in consideration of the operational constraints of the pyrolysis gasification and melting treatment plant so that the dead time is compensated. A control method for a pyrolysis gasification melting treatment plant. A pyrolysis gasification furnace that pyrolyzes the waste introduced by the dust feeder to generate pyrolysis gas, and burns the pyrolysis gas discharged from the pyrolysis gasification furnace and removes ash contained in the pyrolysis gasification furnace. In a control method of a pyrolysis gasification melting treatment plant having a melting furnace for melting,
A step of determining a target trajectory of the control amount from a measured value at the present time and a target value after the present time of the control amount relating to the pyrolysis gasification melting treatment plant;
Obtaining a predicted value of the control amount after the current time;
Obtaining a deviation amount between the target trajectory and the predicted value;
A step of optimizing and determining an operation amount related to the pyrolysis gasification and melting treatment plant in consideration of operating constraints of the pyrolysis gasification and melting treatment plant so that the deviation amount is compensated; Yes, and
A control method for a pyrolysis gasification and melting treatment plant, wherein at least a furnace pressure of the pyrolysis gasification furnace is used to obtain a predicted value of the control amount after the present time .   In obtaining the predicted value of the control amount after the present time, the supply current to the dust feeder, the furnace pressure of the pyrolysis gasification furnace, the exhaust gas flow rate discharged from the melting furnace, and the current of the induction fan The method for controlling a pyrolysis gasification melting treatment plant according to claim 1 or 2, wherein at least one of them is used. The method for controlling a pyrolysis gasification and melting treatment plant according to any one of claims 1 to 5 , wherein at least one of the manipulated variable and the controlled variable is multivariable. The pyrolysis gasification furnace is provided with a fluidized bed at the bottom,
The amount of air blown into the fluidized bed and the amount of dust supplied to the pyrolysis gasification furnace are operated as the operation amount, according to any one of claims 1 to 6. Control method for pyrolysis gasification melting treatment plant. As the manipulated variable, manipulate the amount of air blown into the fluidized bed and the amount of dust supplied to the pyrolysis gasifier,
The method for controlling a pyrolysis gasification melting treatment plant according to claim 7 , wherein a temperature of the fluidized bed and a temperature of the melting furnace are controlled as the control amounts. The pyrolysis gasification melting treatment plant further includes a boiler that recovers heat generated in the pyrolysis gasification furnace and the melting furnace to generate steam;
As the manipulated variable, manipulate the amount of air blown into the fluidized bed and the amount of dust supplied to the pyrolysis gasifier,
The method for controlling a pyrolysis gasification and melting treatment plant according to claim 7 , wherein the control amount is a temperature of the fluidized bed and a flow rate of steam discharged from the boiler. The pyrolysis gasification melting treatment plant further includes a boiler that recovers heat generated in the pyrolysis gasification furnace and the melting furnace to generate steam;
As the operation amount, the amount of air blown into the fluidized bed, the amount of dust supplied to the pyrolysis gasification furnace, and the opening of a steam valve provided in the boiler are operated,
8. The pyrolysis gasification melting plant according to claim 7 , wherein the control amount is controlled by controlling the temperature of the fluidized bed, the flow rate of steam discharged from the boiler, and the pressure of a boiler drum provided in the boiler. Control method. A pyrolysis gasification furnace that is provided with a fluidized bed at the bottom and pyrolyzes the waste introduced by the dust feeder to generate pyrolysis gas, and combusts the pyrolysis gas discharged from the pyrolysis gasification furnace And a control apparatus for a pyrolysis gasification melting treatment plant having a melting furnace for melting the ash contained therein,
Obtaining a predicted value of the control amount related to the pyrolysis gasification melting treatment plant after the present time, and based on the predicted value and the actual measurement value of the control amount at the present time, the pyrolysis gasification so that the dead time is compensated The operation amount related to the melting treatment plant is considered in consideration of the operational constraints of the pyrolysis gasification melting treatment plant, and the constraint conditions are the target treatment amount, the quality of the waste, the temperature of the fluidized bed, and the melting A control apparatus for a pyrolysis gasification and melting treatment plant, wherein the control apparatus is determined and optimized according to at least one of furnace temperatures . A pyrolysis gasification furnace that is provided with a fluidized bed at the bottom and pyrolyzes the waste introduced by the dust feeder to generate pyrolysis gas, and combusts the pyrolysis gas discharged from the pyrolysis gasification furnace And a control apparatus for a pyrolysis gasification melting treatment plant having a melting furnace for melting the ash contained therein,
Means for determining the target trajectory of the controlled variable from the actual measured value of the controlled variable at the present time and the target value after the current time, according to the pyrolysis gasification melting treatment plant;
Means for obtaining a predicted value of the control amount after the present time;
Means for obtaining a deviation amount between the target trajectory and the predicted value;
The operation amount related to the pyrolysis gasification and melting treatment plant so that the deviation amount is compensated, the constraint condition in operation of the pyrolysis gasification and melting treatment plant is taken into account , and the constraint condition is set as the target processing amount, And a means for optimizing and determining after setting according to at least one of the quality of waste, the temperature of the fluidized bed, and the temperature of the melting furnace. Plant control device. A pyrolysis gasification furnace that pyrolyzes the waste introduced by the dust feeder to generate pyrolysis gas, and burns the pyrolysis gas discharged from the pyrolysis gasification furnace and removes ash contained in the pyrolysis gasification furnace. In a control apparatus for a pyrolysis gasification melting treatment plant having a melting furnace for melting,
Using at least the furnace pressure of the pyrolysis gasification furnace, obtain a predicted value of the control amount related to the pyrolysis gasification melting treatment plant from the present time onward, and based on the predicted value and the actual measurement value of the control amount at the present time The operation amount related to the pyrolysis gasification and melting treatment plant is optimized and determined in consideration of the operational constraints of the pyrolysis gasification and melting treatment plant so that the dead time is compensated. A control device for a pyrolysis gasification melting treatment plant. A pyrolysis gasification furnace that pyrolyzes the waste introduced by the dust feeder to generate pyrolysis gas, and burns the pyrolysis gas discharged from the pyrolysis gasification furnace and removes ash contained in the pyrolysis gasification furnace. In a control apparatus for a pyrolysis gasification melting treatment plant having a melting furnace for melting,
Means for determining the target trajectory of the controlled variable from the actual measured value of the controlled variable at the present time and the target value after the current time, according to the pyrolysis gasification melting treatment plant;
Means for obtaining a predicted value of the control amount after the present time;
Means for obtaining a deviation amount between the target trajectory and the predicted value;
Means for optimizing and determining an operation amount related to the pyrolysis gasification and melting treatment plant in consideration of operating constraints of the pyrolysis gasification and melting treatment plant so as to compensate for the deviation amount; Yes, and
A control apparatus for a pyrolysis gasification and melting treatment plant, wherein at least a pressure in the furnace of the pyrolysis gasification furnace is used to obtain a predicted value of the control amount after the present time . In obtaining the predicted value of the control amount after the present time, the supply current to the dust feeder, the furnace pressure of the pyrolysis gasification furnace, the exhaust gas flow rate discharged from the melting furnace, and the current of the induction fan The control apparatus for a pyrolysis gasification melting treatment plant according to claim 11 or 12 , wherein at least one of them is used. The control device for a pyrolysis gasification and melting treatment plant according to any one of claims 11 to 15 , wherein at least one of the manipulated variable and the controlled variable is multivariable. The pyrolysis gasification furnace is provided with a fluidized bed at the bottom,
The amount of air blown into the fluidized bed or the amount of dust supplied to the pyrolysis gasification furnace is operated as the operation amount, according to any one of claims 11 to 16. Control equipment for pyrolysis gasification melting treatment plant. As the manipulated variable, manipulate the amount of air blown into the fluidized bed and the amount of dust supplied to the pyrolysis gasifier,
The control apparatus for a pyrolysis gasification melting processing plant according to claim 17 , wherein the control amount is a temperature of the fluidized bed and a temperature of the melting furnace. The pyrolysis gasification melting treatment plant further includes a boiler that recovers heat generated in the pyrolysis gasification furnace and the melting furnace to generate steam;
As the manipulated variable, manipulate the amount of air blown into the fluidized bed and the amount of dust supplied to the pyrolysis gasifier,
The control device for a pyrolysis gasification and melting treatment plant according to claim 17 , wherein the control amount is a temperature of the fluidized bed and a flow rate of steam discharged from the boiler. The pyrolysis gasification melting treatment plant further includes a boiler that recovers heat generated in the pyrolysis gasification furnace and the melting furnace to generate steam;
As the operation amount, the amount of air blown into the fluidized bed, the amount of dust supplied to the pyrolysis gasification furnace, and the opening of a steam valve provided in the boiler are operated,
18. The pyrolysis gasification melting plant according to claim 17 , wherein, as the control amount, the temperature of the fluidized bed, the flow rate of steam discharged from the boiler, and the pressure of a boiler drum provided in the boiler are controlled. Control device.

Images