JPS61174308A - Furnace pressure control device in converter waste gas treatment device - Google Patents
Furnace pressure control device in converter waste gas treatment deviceInfo
- Publication number
- JPS61174308A JPS61174308A JP60012567A JP1256785A JPS61174308A JP S61174308 A JPS61174308 A JP S61174308A JP 60012567 A JP60012567 A JP 60012567A JP 1256785 A JP1256785 A JP 1256785A JP S61174308 A JPS61174308 A JP S61174308A
- Authority
- JP
- Japan
- Prior art keywords
- control
- furnace pressure
- waste gas
- furnace
- pressure
- 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.)
- Granted
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/28—Manufacture of steel in the converter
- C21C5/38—Removal of waste gases or dust
- C21C5/40—Offtakes or separating apparatus for converter waste gases or dust
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Testing And Monitoring For Control Systems (AREA)
- Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
- Carbon Steel Or Casting Steel Manufacturing (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、転炉廃ガス処理装置における炉圧制御のため
の制御パラメータの適応方法を改良した炉圧制御装置に
関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a furnace pressure control device that improves a method of adapting control parameters for furnace pressure control in a converter waste gas treatment device.
従来の転炉廃ガス処理装置においては、炉口部の上部に
位置するスカートを炉口部に密着させず、適当な間隔を
開けて操業を行なっている。廃ガス回収は炉口部の圧力
Ｐ０を検出し、この圧力Ｐ。In conventional converter waste gas treatment equipment, the skirt located above the furnace mouth is not brought into close contact with the furnace mouth, but is operated with an appropriate gap between the skirts. For waste gas recovery, the pressure P0 at the furnace mouth is detected.
が大気圧Ｐａに等しくなるように、フィードバック制御
にてダンパを操作することにより行なわれる。この時、
炉口とスカート間の間隔が広いと炉圧変動時に多量のガ
ス量の流入、流出を招き、回収率が低下する。逆に、炉
口とスカート間の間隔が狭いとプロセス・ゲインが高く
なり、炉圧制御ループがハンチングを起して操業を続け
ることが困難となる。This is done by operating the damper under feedback control so that the pressure becomes equal to the atmospheric pressure Pa. At this time,
If the gap between the furnace mouth and the skirt is wide, a large amount of gas will flow in and out when the furnace pressure fluctuates, reducing the recovery rate. On the other hand, if the gap between the furnace mouth and the skirt is narrow, the process gain will be high, causing hunting in the furnace pressure control loop and making it difficult to continue operation.
本発明者等はこの解決策として、炉圧制御系が不安定状
態（ハンチング状態）であるか否かを判別し、不安定時
には、調節系の制御パラメータを現在のものより一段弱
いものに変更する方法を提案している。なお、制御系の
不安定状態を判別する判別方式については、特開昭５８
−１６８１０６号公報として公開されているが、と〜で
、その概要について説明する。As a solution to this problem, the inventors determined whether or not the reactor pressure control system was in an unstable state (hunting state), and when it was unstable, changed the control parameters of the adjustment system to ones that were one step weaker than the current ones. We are proposing a method to do so. Note that the determination method for determining the unstable state of the control system is described in Japanese Patent Application Laid-open No. 58
It has been published as Publication No. 168106, and its outline will be explained below.
第３図（イ）は、プロセス変数Ｘの時間的変化の一例を
示したグラフであり、第５図（ロ）は同じ時間における
操作変数Ｙの時間的変化の一例を示したグラフである。FIG. 3(a) is a graph showing an example of a temporal change in the process variable X, and FIG. 5(b) is a graph showing an example of a temporal change in the manipulated variable Y at the same time.
第６図（イ）におけるろ圓の極点（山または谷の頂点）
のＩｆｆ Ｘ１１Ｘ２ ＋Ｘｓと発生時刻ｔＸ１．ｔＸ
２．を追が求まり、また第３図（ロ）における同様な３
個の極点のＩｆｆ Ｙ１＃Ｙ２ ＋Ｙｓと発生時刻ｔＹ
１１ ’Ｙ２’ ｌ ’Ｙ３が求まったものとする。The pole of the circle in Figure 6 (a) (the top of the mountain or valley)
If X11X2 +Xs and the time of occurrence tX1. tX
2. , and similar 3 in Figure 3 (b).
If Y1#Y2 +Ys of the extreme points and the time of occurrence tY
11 'Y2' l 'Y3 is determined.
このとき、Ｘの波形の周期（’Ｘ３− ｔＸｌ ）とＹ
の波形の周期（’Ｙ３− ’Ｙ１ ）を比較し、両者の
比が成る許容範囲ε１の範囲内で１に近いか否かを判定
する。すなわち次の式を満足するか否かを判定する。At this time, the period of the waveform of X ('X3- tXl) and Y
The period of the waveform ('Y3-'Y1) is compared, and it is determined whether the ratio of the two is close to 1 within the tolerance range ε1. That is, it is determined whether the following equation is satisfied.
さらに、波形Ｘの振幅の減衰率が成る所定の減衰率αよ
り大であるかどうかを判定する。すなわち次の式を満足
するか否かを判定する。Furthermore, it is determined whether the attenuation rate of the amplitude of the waveform X is greater than a predetermined attenuation rate α. That is, it is determined whether the following equation is satisfied.
１Ｘ３−Ｘ２１＞α・ｌ Ｘ２− Ｘ１１同様に、波形
Ｙの振幅の減衰率が成る所定の減衰率αより大であるか
どうかを判定する。すなわち次の式を満足するか否かを
判定する。1X3-X21>α·l X2-X11 Similarly, it is determined whether the attenuation rate of the amplitude of the waveform Y is greater than a predetermined attenuation rate α. That is, it is determined whether the following equation is satisfied.
１Ｙ５−Ｙ２１＞α・１Ｙ２−Ｙ１１
以上、３条件が成立したときは制御動作が不安定化した
、つまりＩ・ンチングが発生したと判断する。1Y5-Y21>α・1Y2-Y11 When the above three conditions are satisfied, it is determined that the control operation has become unstable, that is, I-nching has occurred.
しかし、この方法では制御ゲインは弱める方向だけであ
り、したがって、一度制御ゲインを弱めると、強める手
段がないためプロセスゲインの広範口々変動に対しそ制
御ゲインが弱くなる場合が生じるという問題点がある。However, in this method, the control gain can only be weakened. Therefore, once the control gain is weakened, there is no way to strengthen it, so there is a problem that the control gain may become weaker due to wide fluctuations in the process gain. be.
本発明は、前記特開昭５８−１６８１０ｔ５号公報に示
されるような制御の不安定判別方式に対し、制御系が安
定したことを判別する安定判別方式を組み合わせて制御
パラメータを適応させることにより、転炉廃ガス処理装
置における炉圧制御方法の改善を図るものである。The present invention combines the stability determination method for determining whether the control system is stable with the control instability determination method as shown in Japanese Unexamined Patent Publication No. 58-16810t5, and adapts the control parameters. The objective is to improve the furnace pressure control method in converter waste gas treatment equipment.
つまり、特開昭５８−１６８１０６号公報に記載されて
いるプロセス制御の不安定状態判別方式は、要約すると
、プロセスのフィードバック制御において、プロセス変
数が時間に対して振動的に変化し、しかもその振動の減
衰が遅く、操作変数も同じく振動しその減衰が遅いとい
う状態にあり、その上プロセス変数の振動周期と操作変
数の振動周期がほぼ等しければ、ハンチングが発生した
と判断するという原理に立っているが、本発明ではこの
考え方をさらに拡張し、プロセス変数（炉内圧力）およ
び操作変数（調節針出力）が時間に対して振動的に変化
していない状態が一定時間以上継続すれば安定であると
判別し、制御ゲインを一段階強める適応制御を行な５よ
５にする。In other words, the unstable state determination method for process control described in JP-A-58-168106 can be summarized as follows: In process feedback control, a process variable changes oscillatingly with respect to time, and Based on the principle that hunting is determined to have occurred if the oscillation period of the process variable and the oscillation period of the manipulated variable are approximately equal, and the manipulated variable also oscillates and its attenuation is slow. However, in the present invention, this idea is further expanded, and it is determined that the process variable (furnace pressure) and the manipulated variable (control needle output) are stable if they do not change oscillatingly with respect to time for a certain period of time. It is determined that there is, and adaptive control is performed to increase the control gain by one step to 5-5.
第１図は本発明の一実施例を説明するための構成概要図
である。先ず、転炉廃ガス処理装置の構成概要から説明
する。FIG. 1 is a schematic configuration diagram for explaining one embodiment of the present invention. First, an overview of the configuration of the converter waste gas treatment equipment will be explained.
転炉１の中に屑鉄と済ケた銑鉄（溶銑）２を入れた後、
ランス３を通して高圧酸素を吹きつけて精錬（これを吹
錬という）を行ない、吹錬終了後に転炉１を傾けて出鋼
する。この吹錬の際、ランス３から吹き込まれた酸素ジ
ェットは溶けた銑鉄のＣと反応し、ＣＯに富む大量の廃
ガスを発生する。−万、酸素ジェットと鋼浴の衝突面は
非常に高温になり、鋼浴のＦｅが気化するため多量の酸
化鉄粉も発生する。従って、廃ガス処理装置としては、
大量、高温の廃ガスを冷却する設備と集塵する設備とに
分けられる。このようにして発生した高温、多塵の大量
の廃ガスは、誘引送風機１１により誘引されて煙道内を
流れるわけであるが、その際、例えば冷却水管群から成
るガス冷却器７において冷却された後、１次集塵器６に
おいて粗いダストの捕集がなされ、続く２次集塵器８に
おいて微細なダストの最終集塵がなされ、かくして除塵
清浄化された廃ガスは、誘引送風機１１を経て図示せざ
るガスホルダなどに燃料として回収される。ところで、
転炉１においては、吹錬の中期には大証のガスを発生す
るが、その初期や末期においては発生量は少ない。また
吹錬中において副原料を投入したり、ランス３から吹き
つける酸素の量を変えても廃ガスの発生量は変動する。After putting scrap iron and finished pig iron (hot metal) 2 into the converter 1,
Refining (this is called blowing) is performed by blowing high-pressure oxygen through the lance 3, and after the blowing is completed, the converter 1 is tilted to tap the steel. During this blowing, the oxygen jet blown from the lance 3 reacts with the carbon in the molten pig iron, generating a large amount of CO-rich waste gas. -The collision surface between the oxygen jet and the steel bath becomes very high temperature, and a large amount of iron oxide powder is also generated because the Fe in the steel bath is vaporized. Therefore, as a waste gas treatment device,
It is divided into equipment that cools large amounts of high-temperature waste gas and equipment that collects dust. A large amount of high-temperature, dusty waste gas generated in this way is drawn by the induced blower 11 and flows through the flue. After that, coarse dust is collected in the primary dust collector 6, and final collection of fine dust is performed in the subsequent secondary dust collector 8, and the waste gas thus purified is passed through the induced blower 11. It is collected as fuel in a gas holder (not shown) or the like. by the way,
In the converter 1, OSE gas is generated during the middle stage of blowing, but the amount generated is small at the beginning and end of the blowing process. Furthermore, even if auxiliary materials are added during blowing or the amount of oxygen blown from the lance 3 is changed, the amount of waste gas generated varies.
この圧も変動する。そこで、フード５内のガス圧が適当
な範囲内に収まるよう廃ガスの流量制御が行なわれてい
る。This pressure also fluctuates. Therefore, the flow rate of the waste gas is controlled so that the gas pressure within the hood 5 is within an appropriate range.
すなわち、フード５内のガス圧を検出し、炉圧発信器１
２から調節計１４へ送る。調節計１４では、予め設定さ
れている設定値とガス圧を比較し、その差が零になるよ
うに操作出力信号をダンパ操作器１５に送り、２次ダン
パ９の開閉動作を制御して廃ガス流量を調節する。スカ
ート４は、吹錬初期は開放状態で上に上っているが、吹
錬が進むにつれて降下し、炉口に密着するまで降下する
。That is, the gas pressure in the hood 5 is detected, and the furnace pressure transmitter 1
2 to the controller 14. The controller 14 compares the gas pressure with a preset value, and sends an operation output signal to the damper operator 15 so that the difference becomes zero, and controls the opening/closing operation of the secondary damper 9 to eliminate waste. Adjust gas flow rate. At the beginning of blowing, the skirt 4 is in an open state and rises upward, but as the blowing progresses, it descends until it comes into close contact with the furnace mouth.
その後、さらに密閉性を高めるため、外側シール１７を
閉める。この過程において炉口間隔は急変シ、従ってプ
ロセスパラメータも急変する。コノプロセスパラメータ
の変動に対して、制御ハラメータの強弱を炉口圧力と操
作出力より判別し、制御パラメータが強い場合は前述の
如き判別方式によってハンチングを検知し、制御パラメ
ータを１段階弱める。また、制御パラメータが弱い場合
は、１段階強めることにより常に安定且つ最適な制御パ
ラメータを適応させるようにする。Thereafter, the outer seal 17 is closed to further improve sealing performance. During this process, the gap between the furnace openings changes suddenly, and therefore the process parameters also change suddenly. With respect to fluctuations in the conoprocess parameters, the strength of the control harameter is determined from the furnace mouth pressure and the operating output, and if the control parameter is strong, hunting is detected by the above-described determination method and the control parameter is weakened by one step. Furthermore, if the control parameters are weak, the control parameters are strengthened by one step so that stable and optimal control parameters are always applied.
ここで、制御パラメータを１段階強める場合について、
第２図を参照して説明する。なＲ１第２図はかかる場合
の動作を説明するためのフローチャートである。Here, regarding the case where the control parameter is strengthened by one step,
This will be explained with reference to FIG. R1 FIG. 2 is a flowchart for explaining the operation in such a case.
すなわち、炉口圧力（Ｐｏ）と操作出力（ＭＶ）をそれ
ぞれ監視しく■、■′参照）、振動周期が不安定領域に
あるか否かを判別する。なおこの判別の方法としては、
上述の如き不安定化判別方式が用いられることは云う迄
もない。そして、それぞれの振動周期が不安定領域にな
い場合は（■参照）、炉圧Ｐ０の振幅がΔＸ（半固定直
）より小であるか否かを判別する（■参照゛）。上記の
条件がそろつた状態が１秒間以上継続した場合は（■参
照）、プロセスゲインに比べ制御ゲインが弱いものと判
断し、制御ゲインを１段階（１５倍程度）強めて制御を
継続させる。なお、このような処理は、第１図の演算器
１６によって行なわれる。つまり、演算器１６は操業条
件によって変動するプロセスゲインに対し、制御ゲイン
が適正であるか否かを相対的に判別し、適正でない場合
は適宜な制御ゲインを適応させる機能を有している。し
たがって、調節計１４は演算器１６からの出力を受けて
そのゲインを自動的に変更し得る形式のものであり、通
常はディジタル式調節針が使用される。That is, the furnace mouth pressure (Po) and the operating output (MV) are monitored (see (1) and (2), respectively), and it is determined whether or not the vibration period is in the unstable region. The method for this determination is as follows:
It goes without saying that the destabilization determination method described above is used. If each vibration period is not in the unstable region (see ■), it is determined whether the amplitude of the furnace pressure P0 is smaller than ΔX (semi-fixed) (see ■). If the above conditions continue for one second or more (see ■), it is determined that the control gain is weaker than the process gain, and the control gain is increased by one step (approximately 15 times) to continue control. Note that such processing is performed by the arithmetic unit 16 shown in FIG. In other words, the computing unit 16 has a function of relatively determining whether or not the control gain is appropriate with respect to the process gain that varies depending on the operating conditions, and if it is not appropriate, adapting the appropriate control gain. Therefore, the controller 14 is of a type that can automatically change its gain in response to the output from the calculator 16, and usually uses a digital adjustment needle.
なお、上記では主として調節針の比例ゲインを調節する
場合について説明したが、必要に応じて積分時定数や微
分時定数を調節することができる。In addition, although the case where the proportional gain of the adjustment needle is mainly adjusted has been described above, the integral time constant and the differential time constant can be adjusted as necessary.
本発明によれば、スカート高さの急変、外側シール開閉
によるスカートと炉口間の間隔の急変によるプロセスゲ
イン変化に対し、その時の制御パラメータの適正値をハ
ンチング傾向にあるか否かで判別し、その結果に応じて
適正な制御パラメータを適応させることが出来るので、
通常操業から密閉操業までの広範囲な操業が可能となり
、廃ガス回収率の向上、操業の安定化を図ることができ
る利点がもたらされる。According to the present invention, when a process gain changes due to a sudden change in the skirt height or a sudden change in the gap between the skirt and the furnace opening due to the opening and closing of the outer seal, the appropriate value of the control parameter at that time is determined based on whether or not there is a hunting tendency. , it is possible to adapt appropriate control parameters according to the results.
It enables a wide range of operations from normal operations to closed operations, and has the advantage of improving the waste gas recovery rate and stabilizing operations.
第１図は本発明の実施例を示す概略構成図、第２図は制
御パラメータを一段強める場合の動作を説明するための
フローチャート、第３図は不安定化判別方式を説明する
ためのグラフである。
符号説明
１・・・・・・転炉、２・・・・・・溶銑、３・・・・
・・ランス、４・・・・・・スカート、５・・・・・・
フード、６・・・・・・１次集塵器、７・・・・・・ガ
ス冷却器、８・・・・・・２次集塵器、９・・・・・・
２次ダンパ、１０・・・・・・ベンチュリ、１１・・・
・・・誘引送風機、１２・・・・・・炉圧発信器、１３
・・・・・・スカート位置計、１４・・・・・・炉圧調
節計、１５・・・・・・ダンパ操作端、１６・・・・・
・演算器、１７・・・・・・外側シール。
代理人 弁理士 運 木 昭 夫
代理人 弁理士 松 崎 清
第２図
１戸口μ力（ρ０） ■）土カ＜
ｎｖン１＃２■丁、７・Fig. 1 is a schematic configuration diagram showing an embodiment of the present invention, Fig. 2 is a flow chart for explaining the operation when the control parameters are further strengthened, and Fig. 3 is a graph for explaining the destabilization determination method. be. Code explanation 1...Converter, 2...Hot metal, 3...
...Lance, 4...Skirt, 5...
Hood, 6...Primary dust collector, 7...Gas cooler, 8...Secondary dust collector, 9...
Secondary damper, 10...Venturi, 11...
... Induced blower, 12 ... Furnace pressure transmitter, 13
... Skirt position meter, 14 ... Furnace pressure regulator, 15 ... Damper operation end, 16 ...
- Arithmetic unit, 17...Outer seal. Agent Patent attorney Akio Ki Agent Kiyoshi Matsuzaki Figure 2 1 Door μ force (ρ0) ■) Earth force <
nvn1#2■ding,7・
Claims (1)
設定値と比較しその偏差に応じた制御信号を出力する炉
圧調節手段と、該調節手段からの制御信号にもとづいて
炉内から発生する廃ガスの流量を制御する流量制御手段
とからなり、該炉圧を所定値となるように制御する転炉
廃ガス処理装置における炉圧制御装置において、前記調
節手段からの操作出力および炉圧にもとづいて調節手段
の所定時点における制御パラメータの適否を判別する判
別手段を設け、該判別結果にもとづいてその時点のプロ
セスパラメータに適応するように調節手段の制御パラメ
ータを変更することを特徴とする転炉廃ガス処理装置に
おける炉圧制御装置。Furnace internal pressure (furnace pressure) detection means, furnace pressure adjustment means for comparing the detected furnace pressure with a predetermined set value and outputting a control signal according to the deviation, and based on the control signal from the adjustment means. A furnace pressure control device in a converter waste gas processing apparatus, which comprises a flow rate control means for controlling the flow rate of waste gas generated from inside the furnace, and controls the furnace pressure to a predetermined value, wherein an operation from the adjusting means is provided. A determination means is provided for determining whether or not the control parameters of the adjustment means are appropriate at a predetermined time point based on the output and furnace pressure, and the control parameters of the adjustment means are changed to adapt to the process parameters at that time based on the determination result. A furnace pressure control device in a converter waste gas treatment device, characterized by:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60012567A JPS61174308A (en) | 1985-01-28 | 1985-01-28 | Furnace pressure control device in converter waste gas treatment device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60012567A JPS61174308A (en) | 1985-01-28 | 1985-01-28 | Furnace pressure control device in converter waste gas treatment device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61174308A true JPS61174308A (en) | 1986-08-06 |
| JPH0411604B2 JPH0411604B2 (en) | 1992-03-02 |
Family
ID=11808927
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60012567A Granted JPS61174308A (en) | 1985-01-28 | 1985-01-28 | Furnace pressure control device in converter waste gas treatment device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61174308A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6720071B2 (en) | 2001-02-21 | 2004-04-13 | Ntn Corporation | Tip seal and seal material for scroll type compressor |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5772629B2 (en) * | 2012-01-27 | 2015-09-02 | 新日鐵住金株式会社 | Steam pressure control method |
-
1985
- 1985-01-28 JP JP60012567A patent/JPS61174308A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6720071B2 (en) | 2001-02-21 | 2004-04-13 | Ntn Corporation | Tip seal and seal material for scroll type compressor |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0411604B2 (en) | 1992-03-02 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |