JPH09287011A - Method for detecting clogging of transport pipe for blast furnace injection of powder fuel - Google Patents
Method for detecting clogging of transport pipe for blast furnace injection of powder fuelInfo
- Publication number
- JPH09287011A JPH09287011A JP10028596A JP10028596A JPH09287011A JP H09287011 A JPH09287011 A JP H09287011A JP 10028596 A JP10028596 A JP 10028596A JP 10028596 A JP10028596 A JP 10028596A JP H09287011 A JPH09287011 A JP H09287011A
- Authority
- JP
- Japan
- Prior art keywords
- flow rate
- detected
- pressure
- clogging
- blowing
- 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.)
- Withdrawn
Links
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- Air Transport Of Granular Materials (AREA)
- Blast Furnaces (AREA)
Abstract
(57)【要約】
【課題】 従来技術である検出配管温度の搬送気体によ
る冷却効果による詰まり検知法は、検出温度の状態変化
を判定するため、確実に詰まりは検知できるが、検出温
度の状態変化を検知するまでに、極めて多くの時間を要
するという問題があった。
【解決手段】 本発明は輸送配管に流れる吹込流量を流
量検出器により検出し、この検出流量信号をプログラマ
ブル調節計へ入力し、予め定めた時間に予め定めた流量
まで検出吹込流量が減少したことを、プログラマブル調
節計で演算処理し、その直後、該流量検出器下流の近傍
に設置された圧力計による該輸送配管に流れる吹込圧力
信号を検出し、予め定めた時間に予め定めた圧力まで該
検出吹込圧力が低下したことをプログラマブル調節計で
演算処理し、該輸送配管の詰まりを判定することを特徴
とする。
(57) [Abstract] [Problem] A clogging detection method based on a cooling effect of a carrier gas of a detection pipe temperature, which is a conventional technique, can detect a clogging surely because a state change of a detection temperature is determined, but a detection temperature state is detected. There is a problem that it takes an extremely long time to detect the change. According to the present invention, a flow rate detector detects a flow rate of blown air flowing in a transportation pipe, inputs the detected flow rate signal to a programmable controller, and the detected blown flow rate is reduced to a predetermined flow rate at a predetermined time. Is calculated by a programmable controller, and immediately thereafter, a blow-in pressure signal flowing in the transportation pipe is detected by a pressure gauge installed in the vicinity of the flow rate detector, and the pressure is adjusted to a predetermined pressure at a predetermined time. It is characterized in that the decrease in the detected blown pressure is calculated by a programmable controller to determine the clogging of the transportation pipe.
Description
【０００１】[0001]
【発明の属する技術分野】本発明は粉体燃料の高炉吹込
用輸送配管の詰まりを該輸送配管に流れる吹込流量及び
吹込圧力の状態変化により検知する方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting clogging of a blast furnace blowing transport pipe for powder fuel by detecting a change in the blowing flow rate and the blowing pressure flowing through the transport pipe.
【０００２】[0002]
【従来の技術】一般に、高炉に粉体燃料を吹込む場合は
空気または窒素ガス等の搬送気体による気体輸送手段が
採用されており、輸送配管内は固気２相流となってい
る。この輸送配管は内部の粉体燃料の詰まりや摩耗によ
る配管破損に至ることが考えられ、高炉の操業効率を向
上するにはこれらの異常を的確に検知する必要がある。
この異常を検知する手段として、従来、輸送配管温度と
搬送気体による冷却効果の減少により配管の詰まりを検
知する方法が特開昭６２−９３３０５号公報に開示され
ている。この従来の方法は、輸送配管の高炉からの輻射
熱を受ける部分の配管温度の状態変化から上記輻射熱に
対する搬送気体による冷却効果を求め、該冷却効果が減
少した時、輸送配管が詰まったと判定していた。2. Description of the Related Art Generally, when a powdered fuel is blown into a blast furnace, a gas transportation means using a carrier gas such as air or nitrogen gas is adopted, and a solid-gas two-phase flow is formed in the transportation pipe. It is conceivable that this transportation pipe will be clogged due to clogging and abrasion of the powder fuel inside, and it will be necessary to accurately detect these abnormalities in order to improve the operating efficiency of the blast furnace.
As a means for detecting this abnormality, Japanese Patent Laid-Open No. 62-93305 discloses a method of detecting clogging of a pipe by reducing the temperature of the transport pipe and a cooling effect of a carrier gas. In this conventional method, the cooling effect of the carrier gas on the radiant heat is obtained from the change in the pipe temperature of the portion of the transportation pipe that receives the radiant heat from the blast furnace, and when the cooling effect decreases, it is determined that the transport piping is clogged. It was
【０００３】[0003]
【発明が解決しようとする課題】前記の検出配管温度の
搬送気体による冷却効果による詰まり検知法は、結局、
検出温度の状態変化を判定するため、確実に詰まりは検
知できるが、該検出温度の状態変化を検知するまでに極
めて多くの時間を要するという問題があった。本発明
は、従来の方法が有する以上のような問題点を解消し、
配管の詰まりをいち早く検知することができる方法を提
供することを目的としている。The clogging detection method based on the cooling effect of the carrier gas at the temperature of the detection pipe is,
Since the state change of the detected temperature is determined, the clogging can be surely detected, but there is a problem that it takes an extremely long time to detect the state change of the detected temperature. The present invention solves the above problems of the conventional method,
It is an object of the present invention to provide a method capable of quickly detecting clogging of piping.
【０００４】[0004]
【課題を解決するための手段】高炉炉内に粉体燃料を搬
送気体により吹込み供給する吹込用輸送配管の詰まり検
知方法において、輸送配管内を流れる粉体燃料は正常に
吹き込みがなされている時には一定の吹込流量、一定の
吹込圧力の吹込状態にある。そして、この正常吹込時に
輸送配管に詰まりが発生し、上記詰まりに至ると該吹込
流量が減少し、その直後、上記吹込圧力が瞬時に低下す
る。In a method for detecting clogging of a blowing transport pipe for supplying a powder fuel by blowing a carrier gas into a blast furnace, the powder fuel flowing in the transport pipe is normally blown. At times, it is in a blowing state with a constant blowing flow rate and a constant blowing pressure. Then, during the normal blowing, the transportation pipe is clogged, and when the clogging is reached, the flow rate of the blowing is reduced, and immediately after that, the blowing pressure is instantaneously reduced.
【０００５】本発明は輸送配管に流れる吹込流量を流量
検出器により検出し、この検出流量信号をプログラマブ
ル調節計へ入力し、予め定めた時間に予め定めた流量ま
で該検出吹込流量が減少したことを該プログラマブル調
節計で演算処理し、その直後、該流量検出器下流の近傍
に設置された圧力計による該輸送配管に流れる吹込圧力
を検出し、予め定めた時間に予め定めた圧力まで該検出
吹込圧力が低下したことを該プログラマブル調節計で演
算処理し、該輸送配管の詰まりを判定することを特徴と
している。According to the present invention, the flow rate of the blown air flowing through the transportation pipe is detected by the flow rate detector, the detected flow rate signal is input to the programmable controller, and the detected blown flow rate is reduced to a predetermined flow rate at a predetermined time. Is calculated by the programmable controller, and immediately after that, the blowing pressure flowing in the transport pipe is detected by a pressure gauge installed near the flow rate detector, and the pressure is detected up to a predetermined pressure at a predetermined time. A feature of the present invention is that the decrease in the blowing pressure is calculated by the programmable controller to determine the clogging of the transportation pipe.
【０００６】[0006]
【発明の実施の形態】本発明では正常な吹込状態では、
輸送配管内には所定の吹込流量・吹込圧力の粉体燃料が
流れている。この状態で輸送配管内で詰まりが発生する
と、流量が一定時間後に減少し、その直後、圧力が急激
に低下しこれにより輸送配管の詰まりを検知できる。BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, in a normal blowing state,
Powdered fuel with a predetermined flow rate and pressure is flowing in the transportation piping. When clogging occurs in the transportation pipe in this state, the flow rate decreases after a certain period of time, and immediately after that, the pressure sharply decreases, whereby clogging of the transportation pipe can be detected.
【０００７】以下、本発明について実施例の図面を参照
しながら説明する。図１は本発明の実施例を説明するた
めの粉体燃料を高炉内に吹込む状況を示す概念図であ
る。図１において、１は高炉であり、これの羽口１ａに
はブローパイプ２が接続されており、該ブローパイプ２
に粉体燃料輸送配管３が接続されている。該輸送配管３
の上流側には合流部４を介して粉体配管５と搬送気体配
管６が接続されている。また、輸送配管３の下流側はフ
レキシブルホース１０及び粉体燃料吹込ランス１１を介
してブローパイプ２に接続されている。The present invention will be described below with reference to the drawings of the embodiments. FIG. 1 is a conceptual diagram showing a situation in which powder fuel is blown into a blast furnace for explaining an embodiment of the present invention. In FIG. 1, reference numeral 1 is a blast furnace, and a blow pipe 2 is connected to a tuyere 1a of the blast furnace.
The powder fuel transportation pipe 3 is connected to. The transportation pipe 3
A powder pipe 5 and a carrier gas pipe 6 are connected to the upstream side of the through a junction 4. The downstream side of the transportation pipe 3 is connected to the blow pipe 2 via a flexible hose 10 and a powder fuel injection lance 11.
【０００８】そして、この輸送配管３の合流部４の少し
下流側に流量計７が取付けられ、該流量計７の下流側に
圧力計８が取付けられており、両者はいずれもプログラ
マブル調節計９に電気的に接続されている。該プログラ
マブル調節計９は該流量計７からの検出流量が入力さ
れ、該流量の状態変化を監視し、さらに、該圧力計８の
検出圧力が入力され、該プログラマブル調節計９にて演
算処理されて、詰まり検知を行う。A flow meter 7 is mounted slightly downstream of the merging portion 4 of the transport pipe 3, and a pressure gauge 8 is mounted downstream of the flow meter 7, both of which are programmable controllers 9 Electrically connected to. The programmable controller 9 receives the detected flow rate from the flow meter 7, monitors a change in the state of the flow rate, and further receives the detected pressure of the pressure gauge 8 to be processed by the programmable controller 9. To detect clogging.
【０００９】次に、本実施例装置における詰まり発生の
判断動作について説明する。粉体５から供給された粉体
燃料、例えば、微粉炭は配管６から吹込まれる搬送気
体、例えば、空気と合流部４で混合された後、固気２相
流となって輸送配管内３を輸送され、フレキシブルホー
ス１０を経て吹込ランス１１から高炉１の炉内に吹込ま
れる。Next, the operation of determining the occurrence of clogging in the apparatus of this embodiment will be described. The powder fuel supplied from the powder 5, for example, pulverized coal, is mixed with a carrier gas blown from the pipe 6, for example, air in the confluence section 4, and then becomes a solid-gas two-phase flow to form the inside of the transportation pipe 3 Is blown into the furnace of the blast furnace 1 from the blowing lance 11 through the flexible hose 10.
【００１０】そして、この際に上記流量計７及び圧力計
８により輸送配管３の流量及び圧力が検出され、各々、
吹込流量信号値Ｆ１および吹込圧力信号値Ｐ１として出
力される。この検出吹込流量信号及び検出吹込圧力信号
によりプログラマブル調節計９が以下に述べる条件によ
り詰まりを検知する。図２および図３に示す通り、正常
吹込時においては吹込流量信号Ｆ１及び吹込圧力信号Ｐ
１は正常な状態、即ち、ほぼ一定の状態で推移する。こ
こで、配管に詰まりが発生すると、吹込流量信号Ｆ１は
Δｔ1 秒後に初期詰まり吹込流量信号Ｆ２へと状態変化
する。該初期詰まり吹込流量信号Ｆ２が約６０秒間継続
したら初期の詰まりと判定し、初期詰まりの警報を発生
させる。さらに、吹込流量信号Ｆ２がΔｔ2 秒後に末期
詰まり吹込流量信号Ｆ３へと状態変化する。この時、該
末期詰まり吹込流量信号Ｆ３が約６０秒間継続したら、
末期の詰まりと判定し、末期詰まりの警報を発生させ
る。該末期詰まり吹込流量信号Ｆ３がさらに継続した状
態で吹込圧力信号Ｐ１がΔｔ3 秒後に異常吹込圧力Ｐ
２、例えば、２〜３kg／cm2 へと急激に低下した時、配
管の詰まりと判定する。At this time, the flow rate and the pressure of the transportation pipe 3 are detected by the flow meter 7 and the pressure gauge 8, respectively.
It is output as the blow flow rate signal value F1 and the blow pressure signal value P1. The programmable controller 9 detects clogging under the following conditions based on the detected blow-in flow rate signal and the detected blow-in pressure signal. As shown in FIGS. 2 and 3, at the time of normal blowing, the blowing flow rate signal F1 and the blowing pressure signal P
1 changes in a normal state, that is, a substantially constant state. When the pipe is clogged, the blow-in flow rate signal F1 changes to the initial clogged blow-in flow rate signal F2 after Δt 1 second. When the initial clogging blow-in flow rate signal F2 continues for about 60 seconds, it is determined that the clogging is initial and an alarm for the initial clogging is generated. Further, the blow-in flow rate signal F2 changes to the blow-in flow rate signal F3 in the final stage after Δt 2 seconds. At this time, if the terminal blockage blow-in flow rate signal F3 continues for about 60 seconds,
Judges as a terminal blockage and issues a terminal blockage alarm. The blow-in pressure signal P1 becomes Δt 3 seconds after the terminal blockage blow-in flow rate signal F3 continues, and the abnormal blow-in pressure P
2, for example, when it rapidly drops to 2-3 kg / cm 2 , it is determined that the pipe is clogged.
【００１１】尚、図４はプログラマブル調節計の演算処
理のロジックをフローチャートで表したものであり、そ
の説明を以下に示す。２１は吹込流量信号Ｆ２以上Ｆ１
以下で正常吹込圧力信号Ｐ１を判定する回路２２は２１
項の条件を満足すれば、正常状態となる。２３は２１項
の条件を満足しない時、吹込流量信号Ｆ２以下Ｆ３以
上、即ち、初期の詰まり検知を判定する回路、２４は２
３項の継続状態を監視するタイマーである。２５はタイ
マーがタイムアップした時、初期の詰まり検知の警報を
発生させる。２６は２３項の状態からさらに吹込流量信
号Ｆ３以下になった時、即ち、末期の詰まり検知を判定
する回路、２７は２６項の継続状態を監視するタイマー
である。２８はタイマーがタイムアップした時、末期の
詰まり検知の警報を発生させる。２９は吹込流量信号Ｆ
３以下の状態で異常吹込圧力信号Ｐ２を判定する回路、
３０は２９項の継続状態を監視するタイマーである。３
１はタイマーがタイムアップした時、詰まり検知の警報
を発生させる。FIG. 4 is a flow chart showing the logic of the arithmetic processing of the programmable controller, the explanation of which is given below. 21 is the blown flow rate signal F2 or more F1
In the following, the circuit 22 for judging the normal blowing pressure signal P1 is 21
If the conditions of the term are satisfied, it will be in a normal state. When 23 does not satisfy the condition of 21, the blow flow rate signal F2 or less and F3 or more, that is, a circuit for judging the initial clogging detection, and 24 is 2
It is a timer that monitors the continuation status of item 3. 25, when the timer times out, issues an initial clogging detection alarm. Reference numeral 26 is a circuit for determining the clogging detection at the end of the period when the blow flow rate signal F3 is further decreased from the state of 23, and 27 is a timer for monitoring the continuous state of 26. Numeral 28 gives an alarm for detecting clogging at the end when the timer times out. 29 is a blow-in flow rate signal F
A circuit for determining the abnormal blow pressure signal P2 in a state of 3 or less,
Reference numeral 30 is a timer for monitoring the continuation state of item 29. 3
No. 1 issues a clogging detection alarm when the timer times out.
【００１２】[0012]
【発明の効果】以上のように本発明に関わる粉体燃料の
高炉吹込用輸送配管における詰まり検知方法によれば、
輸送配管内の吹込流量及び吹込圧力の状態変化を観測
し、吹込流量がある一定時間にて減少し、その直後、吹
込圧力が低下することにより詰まり検知を判断するよう
にしたので、以下に示す効果があることは勿論のこと、
高炉の操業をより安定にする効果がある。As described above, according to the clogging detection method in the blast furnace injection transportation pipe for powder fuel according to the present invention,
The state change of the blow flow rate and the blow pressure in the transportation pipe was observed, and the blow flow rate decreased in a certain period of time and immediately after that, the clogging detection was judged by the drop of the blow pressure. Not to mention the effect,
It has the effect of stabilizing the operation of the blast furnace.
【００１３】（１）詰まり検知の警告 （２）短時間での詰まり検知 （３）（２）項により配管の破損が完全に防止できる。(1) Warning for detection of clogging (2) Detection of clogging in a short time (3) The damage of the pipe can be completely prevented by the item (2).
【図１】本発明を粉体吹込設備に適用した実施例を示す
概略図である。FIG. 1 is a schematic diagram showing an example in which the present invention is applied to a powder blowing facility.
【図２】検出吹込流量信号の時間特性を示す図である。FIG. 2 is a diagram showing a time characteristic of a detected blown flow rate signal.
【図３】検出吹込圧力信号の時間特性を示す図である。FIG. 3 is a diagram showing a time characteristic of a detected blowing pressure signal.
【図４】本発明の実施例におけるタイムチャートを示す
図である。FIG. 4 is a diagram showing a time chart in the embodiment of the invention.
１…高炉 １ａ…羽口 ２…ブローパイプ ３…輸送配管 ４…合流部 ５…粉体配管 ６…搬送気体配管 ７…流量計 ８…圧力スイッチ ９…プログラマブル調節計 １０…フレキシブルホース １１…ランス DESCRIPTION OF SYMBOLS 1 ... Blast furnace 1a ... Tuyere 2 ... Blow pipe 3 ... Transport pipe 4 ... Confluence part 5 ... Powder pipe 6 ... Carrier gas pipe 7 ... Flow meter 8 ... Pressure switch 9 ... Programmable controller 10 ... Flexible hose 11 ... Lance
───────────────────────────────────────────────────── フロントページの続き (72)発明者 家治 元三郎 福岡県北九州市戸畑区大字中原46−59 新 日本製鐵株式会社機械・プラント事業部内 (72)発明者 大島 孝晴 福岡県北九州市戸畑区大字中原46−59 新 日本製鐵株式会社機械・プラント事業部内 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Genzaburo Ieji 46-59 Nakahara, Tobata-ku, Kitakyushu, Fukuoka 46-59 Nippon Steel Corporation Machinery & Plant Division (72) Takaharu Oshima Tobata-ku, Kitakyushu, Fukuoka Nakahara 46-59 Nippon Steel Corporation Machinery & Plant Division
Claims (1)
込み供給する吹込用輸送配管の詰まり検知方法におい
て、該輸送配管に流れる吹込流量を流量検出器により検
出し、この検出吹込流量信号をプログラマブル調節計へ
入力し、予め定めた時間に予め定めた流量まで該検出吹
込流量が減少したことを該プログラマブル調節計で演算
処理し、その直後、該流量検出器下流の近傍に設置され
た圧力計による該輸送配管に流れる吹込圧力を検出し、
予め定めた時間に予め定めた圧力まで該検出吹込圧力が
低下したことを該プログラマブル調節計で演算処理し、
該輸送配管の詰まりを判定することを特徴とする粉体燃
料の高炉吹込用輸送配管の詰まり検知方法。1. A method for detecting clogging of a blowing transportation pipe for supplying powder fuel into a blast furnace by blowing a carrier gas, wherein a blowing flow rate flowing through the transportation pipe is detected by a flow rate detector, and the detected blowing flow rate signal is detected. Is input to the programmable controller, and the programmable controller calculates that the detected blown flow rate has decreased to a predetermined flow rate at a predetermined time, and immediately after that, it is installed near the flow rate detector downstream. Detecting the blow pressure flowing through the transport pipe with a pressure gauge,
The programmable controller calculates that the detected blowing pressure has decreased to a predetermined pressure at a predetermined time,
A method for detecting clogging of a powder fuel blast furnace blowing transportation pipe, characterized by determining clogging of the transportation pipe.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10028596A JPH09287011A (en) | 1996-04-22 | 1996-04-22 | Method for detecting clogging of transport pipe for blast furnace injection of powder fuel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10028596A JPH09287011A (en) | 1996-04-22 | 1996-04-22 | Method for detecting clogging of transport pipe for blast furnace injection of powder fuel |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH09287011A true JPH09287011A (en) | 1997-11-04 |
Family
ID=14269929
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10028596A Withdrawn JPH09287011A (en) | 1996-04-22 | 1996-04-22 | Method for detecting clogging of transport pipe for blast furnace injection of powder fuel |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH09287011A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100376517B1 (en) * | 1999-08-26 | 2003-03-17 | 주식회사 포스코 | Apparatus for controlling air purge into feed line |
| JP2013237879A (en) * | 2012-05-11 | 2013-11-28 | Jfe Steel Corp | Method for blowing pulverized coal in blast furnace and device for detecting blowing abnormality of combustion-supporting gas |
| CN115815246A (en) * | 2022-12-05 | 2023-03-21 | 核工业理化工程研究院 | Reverse purging method and device for blocking of negative pressure vacuum pipeline |
-
1996
- 1996-04-22 JP JP10028596A patent/JPH09287011A/en not_active Withdrawn
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100376517B1 (en) * | 1999-08-26 | 2003-03-17 | 주식회사 포스코 | Apparatus for controlling air purge into feed line |
| JP2013237879A (en) * | 2012-05-11 | 2013-11-28 | Jfe Steel Corp | Method for blowing pulverized coal in blast furnace and device for detecting blowing abnormality of combustion-supporting gas |
| CN115815246A (en) * | 2022-12-05 | 2023-03-21 | 核工业理化工程研究院 | Reverse purging method and device for blocking of negative pressure vacuum pipeline |
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