JPH0480157B2 - - Google Patents
Info
- Publication number
- JPH0480157B2 JPH0480157B2 JP17915286A JP17915286A JPH0480157B2 JP H0480157 B2 JPH0480157 B2 JP H0480157B2 JP 17915286 A JP17915286 A JP 17915286A JP 17915286 A JP17915286 A JP 17915286A JP H0480157 B2 JPH0480157 B2 JP H0480157B2
- Authority
- JP
- Japan
- Prior art keywords
- flow rate
- air flow
- chamber
- recovery boiler
- furnace
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000011084 recovery Methods 0.000 claims description 48
- 238000002485 combustion reaction Methods 0.000 claims description 45
- 238000011156 evaluation Methods 0.000 claims description 29
- 238000004364 calculation method Methods 0.000 claims description 20
- 238000000034 method Methods 0.000 claims description 11
- 238000010411 cooking Methods 0.000 claims description 9
- 239000000126 substance Substances 0.000 claims description 7
- 239000002994 raw material Substances 0.000 claims description 5
- 238000001514 detection method Methods 0.000 claims description 4
- 230000001276 controlling effect Effects 0.000 claims 5
- 230000001105 regulatory effect Effects 0.000 claims 4
- 239000007789 gas Substances 0.000 description 16
- 238000010586 diagram Methods 0.000 description 14
- 238000002347 injection Methods 0.000 description 6
- 239000007924 injection Substances 0.000 description 6
- 230000006870 function Effects 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 241001062472 Stokellia anisodon Species 0.000 description 3
- 238000013459 approach Methods 0.000 description 3
- 229920005610 lignin Polymers 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 229920001131 Pulp (paper) Polymers 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000008571 general function Effects 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 229920003043 Cellulose fiber Polymers 0.000 description 1
- -1 and for this purpose Substances 0.000 description 1
- 239000013064 chemical raw material Substances 0.000 description 1
- 230000009194 climbing Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 239000012717 electrostatic precipitator Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- 239000003517 fume Substances 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 239000012716 precipitator Substances 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Landscapes
- Incineration Of Waste (AREA)
- Paper (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、紙パルプ製造工程において生ずる黒
液を燃焼して黒液中に含まれる蒸解用薬剤の原料
を回収するとともに黒液の保有熱量により水蒸気
を発生させる回収ボイラの最適燃焼制御装置に関
し、更に詳しくは最適な操業状態となるように黒
液温度を操作し空気流量を探索して回収ボイラの
燃焼状態を制御する回収ボイラの最適燃焼制御装
置に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention burns black liquor produced in the paper pulp manufacturing process to recover raw materials for cooking chemicals contained in the black liquor, and also recovers the heat capacity of the black liquor. Regarding the optimal combustion control device for a recovery boiler that generates water vapor, more specifically, the optimal combustion for a recovery boiler that controls the combustion state of the recovery boiler by manipulating the black liquor temperature and searching for the air flow rate to achieve the optimal operating state. Regarding a control device.
紙パルプ製造工程中のチツプ蒸解工程において
は、木材中のセルローズ（繊維分）とリグニン
（樹脂分）とを分離して取出す必要があり、この
ためにNaOHを主成分とする薬剤が使用されて
いる。そして、この蒸解工程からは、該蒸解工程
により得られる溶解状態の前記リグニン等有機成
分とNa2SO4やNa2CO3等のいわゆるNaを主成分
とする無機分成分とが混合された黒液と称する廃
溶液が排出される。
In the chip cooking process in the paper pulp manufacturing process, it is necessary to separate and extract the cellulose (fiber content) and lignin (resin content) from the wood, and for this purpose, chemicals containing NaOH as the main component are used. There is. Then, from this cooking process, black is produced, which is a mixture of organic components such as lignin in a dissolved state obtained by this cooking process and inorganic components mainly composed of Na such as Na 2 SO 4 and Na 2 CO 3 . A waste solution called liquid is discharged.
ところで、回収ボイラの機能は、上記黒液を燃
焼して黒液中に含まれるリグニン等有機成分の保
有熱量により発電用あるいは工場用諸設備に供す
る蒸気を発生させることにある。また、回収ボイ
ラのもう１つの機能は、黒液の燃焼熱を利用して
黒液中に含有されるNa2SO4を還元し、これを
Na2Ｓを主成分とする形で炉底に溶融させて前記
蒸解工程に利用する薬剤の原料を回収することに
ある。すなわち、回収ボイラは、紙パルプ製造工
程において排出される黒液を燃焼して熱エネルギ
ーと薬剤の原料を回収するといつた２重の役割を
持つており、紙パルプ工場の操業上極めて重要な
意義を有している。このため、回収ボイラの燃焼
制御は、蒸気発生効率と薬剤回収効率即ちスメル
ト還元率と呼ばれるNa2SO4のNaSへの還元効率
の双方が高く得られるような運転が望まれてい
る。 By the way, the function of the recovery boiler is to burn the black liquor and generate steam that is used for power generation or various factory equipment using the amount of heat held by organic components such as lignin contained in the black liquor. Another function of the recovery boiler is to use the combustion heat of the black liquor to reduce the Na 2 SO 4 contained in the black liquor.
The purpose of this method is to recover the raw material for the chemical that is mainly composed of Na 2 S and melted at the bottom of the furnace to be used in the cooking process. In other words, the recovery boiler has a dual role of burning the black liquor discharged in the pulp and paper manufacturing process to recover thermal energy and raw materials for chemicals, and has extremely important significance in the operation of pulp and paper mills. have. Therefore, the combustion control of the recovery boiler is desired to be operated in such a way that both the steam generation efficiency and the chemical recovery efficiency, that is, the reduction efficiency of Na 2 SO 4 to NaS, which is called the smelt reduction rate, are obtained.
第７図および第８図は以上述べた従来の回収ボ
イラおよびその燃焼制御装置の構成を示す図であ
る。先ず、第７図は回収ボイラを示すものであつ
て、図示されていないがチツプ蒸解工程から廃液
として排出される黒液は噴射ガン１により回収ボ
イラ２の炉内に噴霧される。ここで、噴霧状とさ
れた黒液は炉内で放射熱により浮遊乾燥されて炉
底に落下してチヤーベツド３を形成する。このチ
ヤーベツド３および炉内を浮遊している黒液ある
いは炉内ガス体は燃焼用空気として投入されるチ
ヤーベツド底部空気４、チヤーベツド頂上部空気
５および炉上部空気６により燃焼され、このとき
発生する燃焼排ガス７は過熱器８、ドラム９およ
び節炭器１０を通つて熱交換に供され、さらに電
気集塵器１１を通つて煙突１２から系外へ排ガス
１３として排出される。回収ボイラ２に供給され
る水は節炭器１０において燃焼排ガス７により加
熱されて温水とされ、引き続きドラム９のバンク
チユーブによつて加熱されて蒸気１４とされた後
に過熱器８に送り込まれ、ここで過熱されて主蒸
気１５として主蒸気ライン１６から系外へ取出さ
れる構成となつている。 FIGS. 7 and 8 are diagrams showing the configuration of the conventional recovery boiler and its combustion control device described above. First, FIG. 7 shows a recovery boiler, and although not shown, black liquor discharged as waste liquid from the chip cooking process is sprayed into the furnace of the recovery boiler 2 by an injection gun 1. Here, the atomized black liquor is suspended and dried in the furnace by radiant heat, and falls to the bottom of the furnace to form a chirve bed 3. The black liquor or the gas in the furnace floating in the chamber bed 3 and the inside of the furnace is combusted by the bottom air 4, the top air 5, and the top air 6 of the furnace, which are introduced as combustion air, and the combustion that occurs at this time The exhaust gas 7 is subjected to heat exchange through a superheater 8, a drum 9, and an economizer 10, and further passes through an electric precipitator 11 and is discharged from a chimney 12 to the outside of the system as an exhaust gas 13. The water supplied to the recovery boiler 2 is heated by the combustion exhaust gas 7 in the economizer 10 to become hot water, and then heated by the bank tube of the drum 9 to become steam 14, and then sent to the superheater 8. Here, it is superheated and taken out as main steam 15 from the main steam line 16 to the outside of the system.
一方、チヤーベツド３およびその近傍において
は燃焼熱を利用した高温の還元雰囲気が形成され
る。このとき、黒液中に混入されるNa2SO4はこ
の高温の還元雰囲気でNa2Ｓに還元され、スメル
ト１７（チツプ蒸解用薬剤原料）と称する液体と
して炉底に溶融し、スメルトスパウトロ１８から
系外に回収される。また、黒液中に混入してきた
Na2SO4の熱分解や黒液の燃焼の際に発生する
SO2ガスはチヤーベツド頂上部に発生するNa2ガ
スあるいはNa2Ｏヒユームによつて補捉されて
Na2SO4として固定化され同様にNa2Ｓに還元さ
れる。 On the other hand, in the chamber bed 3 and its vicinity, a high-temperature reducing atmosphere is formed using combustion heat. At this time, Na 2 SO 4 mixed into the black liquor is reduced to Na 2 S in this high-temperature reducing atmosphere, melts at the bottom of the furnace as a liquid called smelt 17 (chemical raw material for chip cooking), and is poured into the smelt spout. 18 and is recovered outside the system. Also, it has been mixed into black liquor.
Generated during thermal decomposition of Na 2 SO 4 and combustion of black liquor
SO 2 gas is captured by Na 2 gas or Na 2 O fume generated at the top of the chamber.
It is fixed as Na 2 SO 4 and similarly reduced to Na 2 S.
次に、第８図は第７図に示す回収ボイラに適用
した従来の一般的な燃焼制御装置を示す図であ
る。即ち、この燃焼制御装置は、第７図に示す回
収ボイラシステムにSO2濃度検出器２１、極値探
索部２２および１次空気流量調節計２３を設け、
この空気流量調節計２３の操作出力を用いてチヤ
ーベツド底部空気４の流量を制御する構成となつ
ている。この装置は、極値探索部２２を用いて山
登り法等の手法により前記SO2濃度が極小となる
ようにチヤーベツド底部空気流量の設定値を探索
し、その探索結果をチヤーベツド底部空気流量調
節計２３へ設定値として供給するものである。 Next, FIG. 8 is a diagram showing a conventional general combustion control device applied to the recovery boiler shown in FIG. 7. That is, this combustion control device includes an SO 2 concentration detector 21, an extreme value search section 22, and a primary air flow rate controller 23 in the recovery boiler system shown in FIG.
The operating output of the air flow rate controller 23 is used to control the flow rate of the air 4 at the bottom of the chamber. This device uses an extreme value search unit 22 to search for a set value of the air flow rate at the bottom of the chamber by a method such as a hill climbing method so that the SO 2 concentration becomes minimum, and the search result is sent to the air flow rate controller 23 at the bottom of the chamber. It is supplied as a setting value to.
ところで、以上のような燃焼制御装置は、チヤ
ーベツド頂上部に投入する空気５の量は一定とし
て取扱うか、または変化させる場合であつてもチ
ヤーベツド底部空気４の流量と一定の比を保つ
か、炉上部空気６の流量と一定の比を保つたまま
操作し、独立した操作量としては扱われなかつ
た。
Incidentally, the above-described combustion control device treats the amount of air 5 injected into the top of the chamber as constant, or even if it is changed, maintains a constant ratio to the flow rate of air 4 at the bottom of the chamber. It was operated while maintaining a constant ratio to the flow rate of the upper air 6, and was not treated as an independent manipulated variable.
しかし、本出願における発明者等の実験結果に
よれば、チヤーベツド底部空気流量を一定に保つ
た場合でも第９図に示す如くSO2濃度を極小イに
するチヤーベツド頂上部空気流量が存在する。ま
た、第１０図に示すように、噴射黒液温度に対し
ても同様のSO2濃度の極小点ロが存在する。更
に、回収ボイラ２の他の評価指標例えば回収ボイ
ラ２の出熱・入熱比を考えた場合、チヤーベツド
底部空気流量を一定とし、チヤーベツド頂上部空
気流量と炉上部空気流量の和を一定としたままチ
ヤーベツド頂上部空気流量を操作すると、第１１
図に示すようにあるチヤーベツド頂上部空気流量
の比率に対して出熱・入熱比が極大となる点ハが
存在する。従つて、これらの実験データから極値
探索をチヤーベツド底部空気流量調節計２３の設
定値のみの探索で行つていた従来の燃焼制御装置
では、概略SO2濃度の極小点を探索することはで
きても、チヤーベツド頂上部空気量を独立に操作
することによつてより低いSO2濃度の燃焼状態を
実現することができないという欠点を有してい
る。また、回収ボイラ２の運転状態の評価指標と
して出熱・入熱比を使用した場合でも同様にチヤ
ーベツド底部空気流量調節計２３のみの探索では
真の極値と異なるより低い出熱・入熱比で回収ボ
イラを燃焼し続ける場合があるという欠点を有し
ている。これらは回収ボイラ２の持つ能力を可能
な限り引出し、その時々の操業側の要請に基づく
多様な評価のもとで最適な運転状態を実現しよう
とする試みが行われるにつれて露呈してきた欠点
でもある。 However, according to the experimental results of the inventors in this application, even when the air flow rate at the bottom of the chamber is kept constant, there is an air flow rate at the top of the chamber that minimizes the SO 2 concentration as shown in FIG. 9. Further, as shown in FIG. 10, there is a similar minimum point of SO 2 concentration with respect to the injected black liquor temperature. Furthermore, when considering other evaluation indicators of the recovery boiler 2, such as the heat output/heat input ratio of the recovery boiler 2, the air flow rate at the bottom of the chamber is constant, and the sum of the air flow rate at the top of the chamber and the air flow rate at the top of the furnace is constant. If you manipulate the air flow rate at the top of the chamber, the 11th
As shown in the figure, there is a point C where the heat output/heat input ratio becomes maximum for a certain ratio of the air flow rate at the top of the chamber. Therefore, with the conventional combustion control device, which searches for extreme values based on these experimental data by searching only the set value of the air flow controller 23 at the bottom of the chamber, it is not possible to search for the approximate minimum point of the SO 2 concentration. However, it has the disadvantage that combustion conditions with lower SO 2 concentration cannot be achieved by independently controlling the amount of air at the top of the chamber. In addition, even when the heat output/heat input ratio is used as an evaluation index of the operating state of the recovery boiler 2, similarly, when searching only for the chamber bed bottom air flow rate controller 23, a lower heat output/heat input ratio different from the true extreme value is found. The disadvantage is that the recovery boiler may continue to burn. These are shortcomings that have been exposed as attempts have been made to maximize the capabilities of the recovery boiler 2 and to achieve optimal operating conditions based on various evaluations based on the demands of the operators at the time. .
本発明は以上のような実情に鑑みてなされたも
ので、チヤーベツド底部空気流量調節手段の設定
値と、チヤーベツド頂上部空気流量調節手段また
は黒液温度調節手段の設定値をそれぞれ独立的に
探索して求めることにより、操業上最も好ましい
最適な点に誘導して回収ボイラの燃焼制御を実行
する回収ボイラの最適燃焼制御装置を提供するこ
とを目的とする。 The present invention has been made in view of the above-mentioned circumstances, and it is possible to independently search for the setting value of the air flow rate adjustment means at the bottom of the chamber, and the setting value of the air flow rate adjustment means at the top of the chamber or the black liquor temperature adjustment means. It is an object of the present invention to provide an optimal combustion control device for a recovery boiler that executes combustion control of the recovery boiler by guiding the combustion control to the optimum point that is most preferable for operation.
そこで、本発明は上記目的を達成するために、
回収ボイラの運転状態の評価指標を求めるととも
に、この評価指標が極値に向うようにチヤーベツ
ド底部用設定値とチヤーベツド頂上部用設定値ま
たは噴射黒液温度の設定値を独立に求め、これら
の設定値を回収ボイラの底部空気流量調節手段と
チヤーベツド頂上部空気流量調節手段または黒液
温度調節手段に与えて空気流量を制御するように
したものである。
Therefore, in order to achieve the above object, the present invention has the following features:
In addition to determining the evaluation index of the operating condition of the recovery boiler, the set value for the bottom of the chamber and the set value for the top of the chamber or the set value of the injection black liquor temperature are determined independently so that this evaluation index approaches the extreme value, and these settings are determined. The air flow rate is controlled by applying the value to the bottom air flow rate control means of the recovery boiler, the chamber top air flow rate control means, or the black liquor temperature control means.
従つて、以上のような手段としたことにより、
チヤーベツド底部空気流量とチヤーベツド頂上部
空気流量または噴射黒液温度との２つの操作量を
操作し、回収ボイラの評価指標が極値となる点を
探索するように動作するので、チヤーベツド底部
空気流量のみを操作した時に隠れて現われてこな
かつた評価指標の真の極値を探索でき、回収ボイ
ラをより最適な点で燃焼制御できるものである。
Therefore, by taking the above measures,
It operates to search for the point where the evaluation index of the recovery boiler reaches an extreme value by manipulating two manipulated variables: the air flow rate at the bottom of the chamber and the air flow rate at the top of the chamber or the injection black liquor temperature, so only the air flow rate at the bottom of the chamber is controlled. It is possible to search for the true extreme value of the evaluation index that has not appeared when operating the system, and the combustion of the recovery boiler can be controlled at a more optimal point.
以下、本発明の一実施例について第１図を参照
して説明する。なお、同図において第８図と同一
部分には同一符号を付して詳しい説明は省略す
る。即ち、本発明装置においては、噴射黒液ライ
ン３１に黒液体積流量検出器３２および黒液密度
検出器３３が設置され、これらの検出器３２，３
３によつて検出された体積流量信号および密度信
号は黒液重量流量演算部３４に供給される。この
黒液重量流量演算部３４は流量信号と密度信号と
を乗算して噴射黒液の重量流量を求め、ここで求
められた黒液重量流量を除算部３５に供給する。
この除算部３５は主蒸気ライン１６に設置された
主蒸気流量検出器３６より主蒸気流量信号が供給
されており、この主蒸気流量を前記黒液重量流量
で除することによりスチームゲインを得るもので
ある。また、電気集塵器１１の後段側に燃焼排ガ
ス７のSO2濃度を検出するSO2濃度検出器３７が
設置され、ここで検出されたSO2濃度信号は前記
除算部３５の出力とともに加重和演算部３８に供
給される。この加重和演算部３８は除算部３５の
出力とSO2濃度の加重和として回収ボイラ２の運
転状態の評価指標を演算によつて求めるものであ
る。
Hereinafter, one embodiment of the present invention will be described with reference to FIG. In this figure, the same parts as in FIG. 8 are given the same reference numerals and detailed explanations are omitted. That is, in the apparatus of the present invention, a black liquor volumetric flow rate detector 32 and a black liquor density detector 33 are installed in the injection black liquor line 31, and these detectors 32, 3
The volumetric flow rate signal and density signal detected by 3 are supplied to a black liquor weight flow rate calculation section 34. The black liquor weight flow rate calculation unit 34 multiplies the flow rate signal and the density signal to determine the weight flow rate of the injected black liquor, and supplies the black liquor weight flow rate determined here to the division unit 35 .
This dividing unit 35 is supplied with a main steam flow rate signal from a main steam flow rate detector 36 installed in the main steam line 16, and obtains a steam gain by dividing this main steam flow rate by the black liquor weight flow rate. It is. Further, an SO 2 concentration detector 37 for detecting the SO 2 concentration of the combustion exhaust gas 7 is installed on the downstream side of the electrostatic precipitator 11, and the SO 2 concentration signal detected here is a weighted sum together with the output of the dividing section 35. The signal is supplied to the calculation unit 38. The weighted sum calculation unit 38 calculates an evaluation index of the operating state of the recovery boiler 2 as a weighted sum of the output of the division unit 35 and the SO 2 concentration.
そして、この加重和演算部３８の出力側に極値
探索部３９およびチヤーベツド底部空気流量、チ
ヤーベツド頂上部空気流量をそれぞれ所定の設定
値に制御するチヤーベツド底部空気流量調節計４
０、チヤーベツド頂上部空気流量調節計４１が設
けられている。この極値探索部３９は加重和演算
部３８の出力として得られる回収ボイラ２の運転
状態の評価指標が極値に向うように前記チヤーベ
ツド底部空気流量調節計４０およびチヤーベツド
頂上部空気流量調節計４１の双方の設定値を上下
させるものである。また、前記節炭器１０の下流
側に燃焼排ガス７のO2濃度を検出するO2濃度検
出器５１、前記節炭器１０の下流側に同じく燃焼
排ガスのCO濃度を検出するCO濃度検出器５２が
それぞれ設置され、これらのO2濃度検出器５１
およびCO濃度検出器５２によつて検出されたO2
濃度信号およびCO濃度信号はそれぞれ対応する
O2濃度調節計５３およびCO濃度調節計５４に供
給される。このO2濃度調節計５３はO2濃度が所
定の設定値となるように操作信号を得、同様に
CO濃度調節計５４はCO濃度が所定の設定値とな
るような操作信号を得るものである。５５は前記
探索部３９の出力として得られるチヤーベツド底
部空気流量設定値とチヤーベツド頂上部空気流量
設定値を加算して出力する加算部、５７はO2濃
度調節計５３の出力またはCO濃度調節計５４の
出力から前記加算部５５の出力を減算して出力す
る減算部であつて、この減算出力は炉上部空気流
量調節計５８の設定値として導入されるようにな
つている。 On the output side of this weighted sum calculation section 38, there is an extreme value search section 39 and a chamber bed bottom air flow rate controller 4 that controls the chamber bed bottom air flow rate and the chamber bed top air flow rate to predetermined set values, respectively.
0. An air flow rate controller 41 is provided at the top of the chamber. The extreme value search section 39 searches the chamber bed bottom air flow rate controller 40 and the chamber bed top air flow rate controller 41 so that the evaluation index of the operating state of the recovery boiler 2 obtained as the output of the weighted sum calculation section 38 tends to the extreme value. This is to raise and lower the setting values for both. Further, an O 2 concentration detector 51 that detects the O 2 concentration of the combustion exhaust gas 7 is provided downstream of the economizer 10, and a CO concentration detector 51 that similarly detects the CO concentration of the combustion exhaust gas is provided downstream of the economizer 10. 52 are installed respectively, and these O 2 concentration detectors 51
and O 2 detected by the CO concentration detector 52
The concentration signal and CO concentration signal correspond to each other.
It is supplied to an O 2 concentration controller 53 and a CO concentration controller 54 . This O 2 concentration controller 53 receives an operation signal so that the O 2 concentration reaches a predetermined set value, and similarly
The CO concentration controller 54 obtains an operation signal that brings the CO concentration to a predetermined set value. Reference numeral 55 denotes an adding unit that adds and outputs the air flow rate set value at the bottom of the chamber obtained as the output of the search unit 39 and the air flow rate set value at the top of the chamber, and 57 denotes the output of the O 2 concentration controller 53 or the CO concentration controller 54. is a subtraction section that subtracts the output of the addition section 55 from the output of and outputs the result, and this subtraction output is introduced as a setting value of the furnace upper air flow rate controller 58.
次に、以上のように構成された装置の動作を説
明する。噴射黒液ライン３１から黒液体積流量信
号および黒液密度信号を受けると、黒液重量流量
演算部３４は両検出器３２，３３の出力を乗算し
て噴射黒液の重量を求めた後、この黒液重量流量
信号を除算部３５に供給する。この除算部３５
は、黒液重量流量のほか、主蒸気流量検出器３６
より主蒸気流量が入力され、該主蒸気流量を黒液
重量流量で除することによりスチームゲイン（出
熱・入熱比）を求めて前記加重和演算部３８に導
入している。この加重和演算部３８にあつては
SO2濃度検出器３７から出力されるSO2濃度と前
記スチームゲインとにそれぞれ所定の加重係数を
乗じこの両者の和を演算することにより、SO2濃
度およびスチームゲインの双方を考慮した回収ボ
イラ２の評価指標を演算し、さらに極値探索部３
９においてその評価指標が極値に向うようにチヤ
ーベツド底部空気流量設定値およびチヤーベツド
頂上部流量設定値を独立に探索し、前記評価指標
が極値となれば前記各空気流量設定値として保持
するように動作するものである。 Next, the operation of the apparatus configured as above will be explained. Upon receiving the black liquor volumetric flow signal and the black liquor density signal from the jetted black liquor line 31, the black liquor weight flow rate calculation unit 34 calculates the weight of the jetted black liquor by multiplying the outputs of both the detectors 32 and 33, and then calculates the weight of the jetted black liquor. This black liquor weight flow rate signal is supplied to the dividing section 35. This division section 35
In addition to the black liquor weight flow rate, the main steam flow rate detector 36
The main steam flow rate is inputted, and by dividing the main steam flow rate by the black liquor weight flow rate, a steam gain (heat output/heat input ratio) is obtained and introduced into the weighted sum calculation section 38. In this weighted sum calculation section 38,
By multiplying the SO 2 concentration outputted from the SO 2 concentration detector 37 and the steam gain by a predetermined weighting coefficient and calculating the sum of the two, the recovery boiler 2 can be operated in consideration of both the SO 2 concentration and the steam gain. The evaluation index is calculated, and the extreme value search unit 3
9, the chamber bed bottom air flow rate set value and the chamber bed top air flow rate set value are independently searched so that the evaluation index approaches an extreme value, and if the evaluation index becomes an extreme value, it is held as each air flow rate set value. This is something that works.
第２図は本発明装置に関連して実施される極値
探索部３９の動作を説明する図である。図中、黒
丸は極値探索部３９によつて設定される空気流量
設定値である。即ち、この極値探索部３９は、現
在および前回および前々回で出力したチヤーベツ
ド底部空気流量、チヤーベツド頂上部空気流量お
よびその時の評価指標の値を記憶し、第３図に示
すように現在、前回および前々回の設定値出力点
を結ぶ三角形のうち、最も評価指標の悪い点（図
では前回）を他の２点の対象点に折り返した点を
次回出力点としてチヤーベツド底部空気流量およ
びチヤーベツド頂上部空気流量の次回探索での設
定値を決定するものである。このような動作を繰
り返すことにより、第２図に示すように評価指標
が極値に向うように前記各空気流量設定値を決定
していくものである。 FIG. 2 is a diagram illustrating the operation of the extreme value search section 39 implemented in connection with the apparatus of the present invention. In the figure, the black circles are air flow rate set values set by the extreme value search section 39. That is, this extreme value search unit 39 stores the current, previous, and two previous outputs of the air flow rate at the bottom of the chamber, the air flow rate at the top of the chamber, and the evaluation index values at that time, and as shown in FIG. Among the triangles connecting the set value output points from two previous times, the point with the worst evaluation index (previous time in the figure) is folded back to the other two target points, and the next output point is set as the air flow rate at the bottom of the chamber and the air flow rate at the top of the chamber. This determines the set value for the next search. By repeating such operations, the air flow rate setting values are determined so that the evaluation index approaches the extreme value as shown in FIG.
一方、O2濃度調節計５３、CO濃度調節計５４
にあつては、O2濃度検出信号およびCO濃度検出
信号を受け、排ガス熱損失が最も少なくなるよう
に予め設定されたO2濃度またはCO2濃度を維持す
るようにチヤーベツド底部空気流量とチヤーベツ
ド頂上部空気流量と炉上部空気流量との和、すな
わち回収ボイラへ投入される全空気流量の設定値
を決定するように動作する。また、チヤーベツド
底部空気流量設定値とチヤーベツド頂上部空気流
量設定値の和を求め、前記調節計５３または５４
の出力を該設定値和で減算出力するようにしてい
るので、極値探索部３９により決定されたチヤー
ベツド底部空気流量、チヤーベツド頂上部空気流
量を保持したまま排ガス熱損失が最も少なくなる
ように炉上部空気流量設定値を決定することがで
きる。 On the other hand, O 2 concentration controller 53 and CO concentration controller 54
In this case, the system receives the O 2 concentration detection signal and the CO concentration detection signal, and adjusts the air flow rate at the bottom of the chamber and the air flow rate at the top of the chamber to maintain a preset O 2 concentration or CO 2 concentration so as to minimize exhaust gas heat loss. It operates to determine the sum of the partial air flow rate and the furnace upper air flow rate, that is, the set value of the total air flow rate input to the recovery boiler. Further, the sum of the air flow rate setting value at the bottom of the chamber and the air flow rate setting value at the top of the chamber is determined, and the controller 53 or 54
Since the output is subtracted by the sum of the set values, the furnace is adjusted so that the exhaust gas heat loss is minimized while maintaining the air flow rate at the bottom of the chamber and the air flow rate at the top of the chamber determined by the extreme value search section 39. A top air flow setpoint can be determined.
従つて、本発明は以上のような実施例の構成に
よれば、チヤーベツド底部空気流量とチヤーベツ
ド頂上部空気流量の２つの操作量を操作し、回収
ボイラの評価指標が極値となる点を探索している
ので、従来装置においてチヤーベツド底部空気流
量のみを操作していた時に隠れて現れて来なかつ
た評価指標の真の極値が第６図に示すようにチヤ
ーベツド空気流量とチヤーベツド頂上空気流量の
双方を操作し探索することにより、真の極値ヘを
発見できるものである。第５図においてニはチヤ
ーベツド底部空気のみを操作した時に到達できる
極大点を示す。 Therefore, according to the configuration of the embodiment described above, the present invention manipulates two manipulated variables, the air flow rate at the bottom of the chamber and the air flow rate at the top of the chamber, and searches for the point where the evaluation index of the recovery boiler reaches an extreme value. Therefore, as shown in Figure 6, the true extreme value of the evaluation index that did not appear when only the air flow rate at the bottom of the chamber was controlled in the conventional equipment is the By manipulating and exploring both, the true extreme value can be discovered. In FIG. 5, D indicates the maximum point that can be reached when only the air at the bottom of the chamber is operated.
なお、本発明は上記実施例に限定されるもので
はない。例えば加重和演算部３８は一般の任意の
関数を与える関数演算部とすることができる。ま
た、このような関数演算部の入力としてはスチー
ムゲイン、SO2濃度信号の他、必要に応じて炉内
温度あるいは燃焼排ガス７のCO2濃度を加えるこ
とができる。また、回収ボイラ２の熱効率に相当
する指標を演算し、これをスチームゲインの代り
に用いれば、回収ボイラにおける運転状態の評価
指標としてより正確になる。また、排ガスライン
にO2濃度検出器５１またはCO濃度検出器５２を
設置し、これに対応してO2濃度調節計５３また
はCO濃度調節計５４の何れか１つを使用しても
よいものである。さらに、第１図に示す加算部５
５は加重和演算部３８あるいは一般の関数演算部
を使用してO2濃度調節計５３の炉上部空気流量
に対する設定感度を調整することも有効である。
また、上記実施例では、極値探索部３９はチヤー
ベツド底部空気流量とチヤーベツド頂上部空気流
量をそれぞれ独立的かつ直接的に決定するように
したが、第４図に示すように全体空気流量に対す
るチヤーベツド底部空気流量の比率および全体空
気流量に対するチヤーベツド頂上部流量の比率、
あるいは炉上部空気流量とチヤーベツド頂上部空
気流量の和に対するチヤーベツド頂上部空気流量
の比率等を用い、O2濃度調節計５３によつて全
体空気流量あるいは炉上部空気流量とチヤーベツ
ド頂上部空気流量の和を設定し、この内比として
空気流量の設定値を決定することもできる。 Note that the present invention is not limited to the above embodiments. For example, the weighted sum calculation unit 38 can be a function calculation unit that provides any general function. In addition to the steam gain and the SO 2 concentration signal, the furnace temperature or the CO 2 concentration of the combustion exhaust gas 7 can be added as inputs to such a function calculation unit, if necessary. Moreover, if an index corresponding to the thermal efficiency of the recovery boiler 2 is calculated and used in place of the steam gain, it becomes more accurate as an evaluation index of the operating state of the recovery boiler. Alternatively, an O 2 concentration detector 51 or a CO concentration detector 52 may be installed in the exhaust gas line, and either one of the O 2 concentration controller 53 or the CO concentration controller 54 may be used accordingly. It is. Furthermore, the adding section 5 shown in FIG.
5, it is also effective to use the weighted sum calculation unit 38 or a general function calculation unit to adjust the setting sensitivity of the O 2 concentration controller 53 to the furnace upper air flow rate.
Further, in the above embodiment, the extreme value search unit 39 independently and directly determines the air flow rate at the bottom of the chamber and the air flow rate at the top of the chamber, but as shown in FIG. the ratio of the bottom air flow rate and the ratio of the top of the chamber flow rate to the total air flow rate;
Alternatively, using the ratio of the air flow rate at the top of the chamber to the sum of the air flow rate at the top of the furnace and the air flow rate at the top of the chamber, the O 2 concentration controller 53 can be used to adjust the total air flow rate or the sum of the air flow rate at the top of the furnace and the air flow rate at the top of the chamber. It is also possible to set the air flow rate and determine the set value of the air flow rate as this internal ratio.
また、他の実施例としては、チヤーベツド頂上
部空気流量に代えて噴射黒液流量の設定値とチヤ
ーベツド底部空気流量の設定値の双方を用いて評
価指標の極値を探索するような構成であつてもよ
い。その他、本発明はその要旨を逸脱しない範囲
で種々変形して実施できる。 In another embodiment, the extreme value of the evaluation index is searched for using both the set value of the black liquor injection flow rate and the set value of the air flow rate at the bottom of the chamber instead of the air flow rate at the top of the chamber. It's okay. In addition, the present invention can be implemented with various modifications without departing from the gist thereof.
〔発明の効果〕
以上詳記したように本発明によれば、チヤーベ
ツド底部空気流量の他にチヤーベツド頂上部空気
流量あるいは噴射黒液温度の設定値を独立に同時
に操作し極値を探索するようにしたので、従来隠
れて現われなかつた評価指標の真の極値を探索で
き、より高いスチームゲインあるいはより低い
SO2濃度等で操業上最適な燃焼状態で燃焼制御で
きる回収ボイラの最適燃焼制御装置を提供でき
る。[Effects of the Invention] As described in detail above, according to the present invention, in addition to the air flow rate at the bottom of the chamber, the set values for the air flow rate at the top of the chamber or the jet black liquor temperature are independently and simultaneously operated to search for extreme values. This allows us to explore the true extreme values of evaluation metrics that were previously hidden and did not appear, allowing us to search for higher steam gain or lower steam gain.
It is possible to provide an optimal combustion control device for a recovery boiler that can control combustion in an operationally optimal combustion state based on SO 2 concentration, etc.
第１図は本発明装置の一実施例を示す構成図、
第２図および第３図は本発明に関連して実施され
る極値探索部の動作を説明する図、第４図は本発
明の他の実施例を説明する構成図、第５図はチヤ
ーベツド底部空気流量とチヤーベツド頂上部空気
流量に対する回収ボイラの運転状態の評価指標の
等高線と従来装置の探索過程例を示す図、第６図
は同様の等高線と本発明装置の探索過程例を示す
図、第７図は従来一般的に使用されている回収ボ
イラの構成図、第８図は従来の回収ボイラの燃焼
制御装置の構成図、第９図はチヤーベツド頂上部
空気流量に対する燃焼排ガスSO2濃度の特性図、
第１０図は噴射黒液温度に対する排ガスSO2濃度
の特性図、第１１図はチヤーベツド頂上部空気流
量と炉上部空気流量との和に対する比と出熱・入
熱比との関係を示す図である。
２……回収ボイラ、３……チヤーベツド、４…
…チヤーベツド底部空気、５……チヤーベツド頂
上部空気、６……炉上部空気、７……燃焼排ガ
ス、３２……黒液体積流量検出器、３３……黒液
密度検出器、３４……黒液重量流量演算部、３５
……除算部、３６……主蒸気流量検出器、３７…
…SO2濃度検出器、３８……加重和演算部、３９
……極値演算部、４０……チヤーベツド底部空気
流量調節計、４１……チヤーベツド頂上部空気流
量調節計、５１……O2濃度検出器、５２……SO2
濃度検出器、５３……O2濃度調節計、５４……
CO濃度調節計、５８……炉上部空気流量調節計。
FIG. 1 is a configuration diagram showing an embodiment of the device of the present invention;
FIGS. 2 and 3 are diagrams explaining the operation of the extreme value search unit implemented in connection with the present invention, FIG. 4 is a configuration diagram explaining another embodiment of the present invention, and FIG. FIG. 6 is a diagram showing contour lines and an example of the search process of the conventional device for the evaluation index of the operating state of the recovery boiler with respect to the bottom air flow rate and the top air flow rate of the chamber; FIG. 6 is a diagram showing similar contour lines and an example of the search process of the device of the present invention; Fig. 7 is a block diagram of a recovery boiler commonly used in the past, Fig. 8 is a block diagram of a combustion control device for a conventional recovery boiler, and Fig. 9 is a diagram of the combustion exhaust gas SO 2 concentration versus the air flow rate at the top of the chamber. Characteristic diagram,
Figure 10 is a characteristic diagram of exhaust gas SO 2 concentration versus injection black liquor temperature, and Figure 11 is a diagram showing the relationship between the ratio of the air flow rate at the top of the chamber to the sum of the air flow rate at the top of the furnace and the heat output/heat input ratio. be. 2...Recovery boiler, 3...Charbed, 4...
... air at the bottom of the chamber bed, 5 ... air at the top of the chamber bed, 6 ... air at the top of the furnace, 7 ... combustion exhaust gas, 32 ... black liquid volumetric flow rate detector, 33 ... black liquor density detector, 34 ... black liquor Weight flow rate calculation section, 35
...Division section, 36... Main steam flow rate detector, 37...
... SO 2 concentration detector, 38 ... Weighted sum calculation section, 39
. . . Extreme value calculation unit, 40 . . . Chamber bed bottom air flow rate controller, 41 . . .
Concentration detector, 53... O 2 concentration controller, 54...
CO concentration controller, 58...Furnace upper air flow rate controller.
Claims (1)
堆積させるとともに同時に燃焼用空気を炉内のチ
ヤーベツド底部およびチヤーベツド頂上部近傍に
投入して前記チヤーベツドを燃焼させることによ
り、黒液中に含まれる蒸解用薬剤の原料を回収す
るとともに燃焼排ガスとの熱交換により水蒸気を
発生させる回収ボイラの最適燃焼制御装置におい
て、前記回収ボイラの運転状態の評価指標を求め
る評価指標演算手段と、前記チヤーベツド底部よ
り投入する燃焼用空気流量を所定の設定値となる
ように制御する第１の調節手段と、前記チヤーベ
ツド頂上部近傍に投入する燃焼用空気流量または
前記黒液の温度の何れかを所定の設定値となるよ
うに制御する第２の調節手段と、これら第１およ
び第２の調節手段の設定値の双方を独立に前記評
価指標が極値に向うように変化させる極値探索手
段とを備えたことを特徴とする回収ボイラの最適
燃焼制御装置。 ２ 評価指標演算手段は、前記回収ボイラの出
熱・入熱比、炉内温度、排ガス中のSO2濃度、同
じく排ガス中のCO2濃度の何れか１つまたは複数
を用いて評価指標を求めるものである特許請求の
範囲第１項記載の回収ボイラの最適燃焼制御装
置。 ３ 極値探索手段は、前記第１、第２の調節手段
の少なくとも現在設定値および前記極値探索手段
によつて得られた少なくとも現在の評価指標の値
をそれぞれ記憶する記憶手段と、この記憶手段に
よつて記憶された過去の記憶データに基づいて前
記第１および第２の調節手段に供給する次回の設
定値を求める演算手段とを有するものである特許
請求の範囲第１項記載の回収ボイラの最適燃焼制
御装置。 ４ 黒液を炉内に噴射して炉底にチヤーベツドを
堆積させると同時に燃焼用空気を炉内のチヤーベ
ツド底部、チヤーベツド頂上部近傍および炉上部
に投入して前記チヤーベツドを燃焼させることに
より、黒液中に含まれる蒸解用薬剤の原料を回収
するとともに燃焼排ガスとの熱交換により水蒸気
を発生させる回収ボイラの最適燃焼制御装置にお
いて、前記回収ボイラの運転状態の評価指標を求
める評価指標演算手段と、前記回収ボイラの排ガ
ス中のO2濃度またはCO濃度を検知する検知手段
と、前記チヤーベツド底部より投入する燃焼用空
気流量を所定の設定値となるように制御する第１
の調節手段と、前記チヤーベツド頂上部近傍に投
入する燃焼用空気流量または前記黒液の温度の何
れかを所定の設定値となるように制御する第２の
調節手段と、前記炉上部に投入する燃焼用空気流
量を所定の設定値となるように制御する第３の調
節手段と、この第３の調節手段の設定値を、前記
第１、第２の調節手段の設定値の少なくとも１つ
と前記検知手段で検知されたO2濃度、CO濃度の
少なくとも１つとに基づいて決定する空気流量決
定手段とを備えたことを特徴とする回収ボイラの
最適燃焼制御装置。 ５ 空気流量決定手段は、全体空気流量に対する
チヤーベツド底部空気流量の比率および全体空気
流量に対するチヤーベツド頂上部空気流量の比率
あるいは炉上部空気流量とチヤーベツド頂上部空
気流量の和に対するチヤーベツド頂上部空気流量
の比率の何れかを用いて設定値を決定するもので
ある特許請求の範囲第４項記載の回収ボイラの最
適燃焼制御装置。[Scope of Claims] 1. By injecting black liquor into the furnace to deposit the chabed at the bottom of the furnace, and at the same time injecting combustion air into the bottom of the furnace and near the top of the chirbett to combust the chabed. In an optimal combustion control device for a recovery boiler that recovers raw materials for cooking chemicals contained in black liquor and generates steam through heat exchange with combustion exhaust gas, an evaluation index calculation for determining an evaluation index of the operating state of the recovery boiler. a first adjusting means for controlling the flow rate of combustion air introduced from the bottom of the chamber bed to a predetermined set value; a second adjusting means for controlling one of the first and second adjusting means to a predetermined setting value; and a control means for independently changing the setting values of both the first and second adjusting means so that the evaluation index moves toward an extreme value. An optimal combustion control device for a recovery boiler, comprising: a value search means. 2. The evaluation index calculating means calculates the evaluation index using any one or more of the heat output/heat input ratio of the recovery boiler, the temperature inside the furnace, the SO 2 concentration in the exhaust gas, and the CO 2 concentration in the exhaust gas. An optimal combustion control device for a recovery boiler according to claim 1. 3. The extreme value search means includes a storage means for storing at least the current setting values of the first and second adjustment means and at least the current value of the evaluation index obtained by the extreme value search means, and this memory. 2. The recovery method according to claim 1, further comprising calculation means for determining the next set value to be supplied to the first and second adjustment means based on past storage data stored by the means. Optimal combustion control device for boilers. 4. Black liquor is injected into the furnace to deposit the chamber bed at the bottom of the furnace, and at the same time combustion air is injected into the bottom of the chamber, near the top of the chamber, and at the top of the furnace to combust the chamber bed. In an optimal combustion control device for a recovery boiler that recovers a raw material for a cooking chemical contained therein and generates steam through heat exchange with combustion exhaust gas, an evaluation index calculation means for calculating an evaluation index of the operating state of the recovery boiler; a detection means for detecting the O 2 concentration or CO concentration in the exhaust gas of the recovery boiler; and a first control means for controlling the flow rate of combustion air introduced from the bottom of the chamber bed to a predetermined set value.
a second adjusting means for controlling either the flow rate of combustion air introduced near the top of the furnace bed or the temperature of the black liquor to a predetermined set value; a third regulating means for controlling the combustion air flow rate to a predetermined set value; and a set value of the third regulating means is set to at least one of the set values of the first and second regulating means and the third regulating means. An optimal combustion control device for a recovery boiler, comprising an air flow rate determination unit that determines the flow rate based on at least one of O 2 concentration and CO concentration detected by the detection unit. 5. The air flow rate determination means determines the ratio of the air flow rate at the bottom of the chamber to the total air flow rate, the ratio of the air flow rate at the top of the chamber to the total air flow rate, or the ratio of the air flow rate at the top of the chamber to the sum of the air flow rate at the top of the furnace and the air flow rate at the top of the chamber. 5. The optimum combustion control system for a recovery boiler according to claim 4, wherein the set value is determined using any one of the following.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16899485 | 1985-07-31 | ||
| JP60-168994 | 1985-07-31 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62123215A JPS62123215A (en) | 1987-06-04 |
| JPH0480157B2 true JPH0480157B2 (en) | 1992-12-17 |
Family
ID=15878379
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17915286A Granted JPS62123215A (en) | 1985-07-31 | 1986-07-30 | Optimum combustion control device for recovery boiler |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62123215A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8215494B2 (en) | 2001-11-13 | 2012-07-10 | Pall Corporation | Filter module and method for its manufacture |
| WO2007017111A1 (en) | 2005-07-28 | 2007-02-15 | Pall Corporation | Filter module and process for manufacture of same |
| WO2007017110A1 (en) | 2005-07-28 | 2007-02-15 | Pall Corporation | Filter module and process for manufacture of same |
| CA2614441C (en) | 2005-07-28 | 2014-02-18 | Pall Corporation | Filter module and process for manufacture of same |
| US7934604B2 (en) | 2006-07-26 | 2011-05-03 | Pall Corporation | Filter module and process for manufacture of same |
-
1986
- 1986-07-30 JP JP17915286A patent/JPS62123215A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62123215A (en) | 1987-06-04 |
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