JP2713640B2 - How to prevent explosion of pulverized coal machine - Google Patents
How to prevent explosion of pulverized coal machineInfo
- Publication number
- JP2713640B2 JP2713640B2 JP13391890A JP13391890A JP2713640B2 JP 2713640 B2 JP2713640 B2 JP 2713640B2 JP 13391890 A JP13391890 A JP 13391890A JP 13391890 A JP13391890 A JP 13391890A JP 2713640 B2 JP2713640 B2 JP 2713640B2
- Authority
- JP
- Japan
- Prior art keywords
- pulverized coal
- coal
- inert
- oxygen concentration
- explosion
- 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 - Lifetime
Links
- 239000003245 coal Substances 0.000 title claims description 76
- 238000004880 explosion Methods 0.000 title claims description 22
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 22
- 239000001301 oxygen Substances 0.000 claims description 22
- 229910052760 oxygen Inorganic materials 0.000 claims description 22
- 238000000034 method Methods 0.000 claims description 9
- 238000010298 pulverizing process Methods 0.000 claims description 4
- 230000002265 prevention Effects 0.000 claims 2
- 238000002485 combustion reaction Methods 0.000 description 7
- 238000001514 detection method Methods 0.000 description 5
- 239000003638 chemical reducing agent Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 238000010926 purge Methods 0.000 description 2
- 108010063955 thrombin receptor peptide (42-47) Proteins 0.000 description 2
- 238000011144 upstream manufacturing Methods 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
Landscapes
- Disintegrating Or Milling (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は、石炭を粉砕する微粉炭機内にイナート媒体
を投入して該微粉炭機内での酸素濃度を下げ、微粉炭の
爆発を防止する微粉炭機の爆発防止方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention reduces the oxygen concentration in a pulverized coal machine by introducing an inert medium into a pulverized coal machine for pulverizing coal, thereby preventing explosion of pulverized coal. The present invention relates to a method for preventing explosion of a pulverized coal machine.
［従来の技術］ 近年、微粉炭焚ボイラでは、発火性が高く揮発成分の
多い石炭が使用されるようになっている。このような発
火性の高い石炭を微粉炭機内で粉砕する場合には、特に
微粉炭が爆発する可能性が高く、この爆発を防止するた
めに該微粉炭機内での酸素濃度を下げるべくN2やCO2、
蒸気などのイナート媒体を投入するしてミルイナートシ
ステムを採用している。[Prior Art] In recent years, pulverized coal-fired boilers have come to use coal having high ignitability and high in volatile components. When such highly ignitable coal is pulverized in a pulverized coal machine, there is a high possibility that the pulverized coal will explode. In order to prevent this explosion, N 2 is used to reduce the oxygen concentration in the pulverized coal machine. Or CO 2 ,
The mill inert system is adopted by introducing an inert medium such as steam.
［発明が解決しようとする課題］ しかしながら上記のミルイナートシステムでは、イナ
ート媒体による酸素の目標希釈度を通常７％乃至11％の
範囲で設定しており、この目標が低すぎるため、イナー
ト媒体の消費量が多くなって付帯設備が過剰となってし
まうばかりか、バーナでの燃焼が不安定になり、ひいて
は失火等を招く恐れがあった。[Problems to be Solved by the Invention] However, in the above-mentioned mill inert system, the target dilution degree of oxygen by the inert medium is usually set in the range of 7% to 11%, and this target is too low. Not only did the consumption increase and the incidental facilities became excessive, but the combustion in the burner became unstable, which could lead to misfires and the like.
また、上記イナート媒体は微粉炭機内のCO濃度をCO計
により検出し、CO濃度が一定の値を越えた際に投入する
ようにしているため、イナート媒体によってCO計に摩耗
や無塞を生じ、信頼性を低下させていた。In addition, since the inert medium detects the CO concentration in the pulverized coal machine with a CO meter and is inserted when the CO concentration exceeds a certain value, the inert medium causes wear and non-blocking of the CO meter. , Had reduced reliability.
本発明は上記のような実情に鑑みてなされたもので、
その目的とするところは、イナート媒体の消費量を少な
くして付帯設備を必要最小限のものとし、バーナの燃焼
を疎外することなく確実に微粉炭の爆発を防止する一
方、状態の検出を行なう機構を排除して該検出機構のト
ラブルを回避し、信頼性を向上させることが可能な微粉
炭機の爆発防止方法を提供することにある。The present invention has been made in view of the above circumstances,
The purpose is to minimize the consumption of inert media, minimize the incidental equipment, and reliably prevent the explosion of pulverized coal without ignoring the combustion of the burner, while detecting the state. An object of the present invention is to provide a method for preventing an explosion of a pulverized coal machine that can eliminate a mechanism, avoid troubles of the detection mechanism, and improve reliability.
［課題を解決するための手段及び作用］ すなわち本発明は、石炭を粉砕する微粉炭機内にイナ
ート媒体を投入して該微粉炭機内での酸素濃度を下げ、
微粉炭の爆発を防止する微粉炭機の爆発防止方法におい
て、微粉炭機内の酸素濃度を13％乃至15％の範囲内とす
べく、微粉炭機に石炭を供給する給炭機の起動時、停止
時及びトリップ時にイナート媒体をシーケンシャルに投
入するようにしたもので、爆発を防止するための酸素濃
度は充分確保しながらもイナート媒体の消費量を少なく
して付帯設備を必要最小限のものとし、バーナの燃焼を
疎外することを回避できる一方、状態の検出を行なう機
構を排除して該検出機構のトラブルをなくし、装置の信
頼性を向上させることができる。[Means and Actions for Solving the Problems] That is, the present invention reduces the oxygen concentration in the pulverized coal machine by introducing an inert medium into a pulverized coal machine that pulverizes coal,
In the method for preventing explosion of pulverized coal, in the method of preventing explosion of pulverized coal, when a coal feeder for supplying coal to the pulverized coal is started in order to keep the oxygen concentration in the pulverized coal within the range of 13% to 15%, The inert medium is sequentially charged at the time of stop and trip.The oxygen concentration for preventing the explosion is sufficiently secured, but the consumption of the inert medium is reduced to minimize the incidental equipment. In addition, it is possible to avoid ignoring the combustion of the burner, while eliminating the mechanism for detecting the state, eliminating the trouble of the detection mechanism, and improving the reliability of the apparatus.
［実施例］ 以下図面を参照して本発明の一実施例を説明する。An embodiment of the present invention will be described below with reference to the drawings.
第１図はその構成を示すもので、１が石炭を供給する
給炭機、２が給炭機１から供給された石炭を粉砕する微
粉炭機であり、微粉炭機２で所定の微粉粒度に粉砕され
た石炭は熱空気ダクト３から導入される熱空気により乾
燥された後、バーナ10へ搬送される。FIG. 1 shows the configuration, wherein 1 is a coal feeder for supplying coal, 2 is a pulverizer for pulverizing the coal supplied from the coal feeder 1, and the pulverizer 2 has a predetermined fine particle size. The coal pulverized into hot air is dried by hot air introduced from the hot air duct 3 and then conveyed to the burner 10.
一方、11はボイラの蒸気ラインであり、この蒸気ライ
ン11から分岐した蒸気をイナート媒体として使用するも
ので、分岐したイナート媒体は減圧弁４及び減温器５を
介して所定の圧力及び温度に減圧、減温された後、ドレ
ントラップ６、ドレンセパレータ９によりドレンを排除
され、蒸気熱空気ダクト３から微粉炭機２内に投入され
る。熱空気ダクト３から微粉炭機２に入る熱空気の量
は、熱空気ダクト３に設けられたオリフィス13により計
測され、その計測結果に応じて熱空気ダクト３のオリフ
ィス13より上流側にあるダンパ14により熱空気の量が制
御される。On the other hand, reference numeral 11 denotes a steam line of a boiler, which uses the steam branched from the steam line 11 as an inert medium, and the branched inert medium is brought to a predetermined pressure and temperature via a pressure reducing valve 4 and a temperature reducer 5. After the pressure is reduced and the temperature is reduced, the drain is removed by the drain trap 6 and the drain separator 9, and the drain is charged into the pulverized coal machine 2 from the steam hot air duct 3. The amount of hot air entering the pulverizer 2 from the hot air duct 3 is measured by an orifice 13 provided in the hot air duct 3, and a damper located upstream of the orifice 13 of the hot air duct 3 according to the measurement result. 14 controls the amount of hot air.
上記ドレントラップ６にはドレン排出弁７が配設さ
れ、排除されたドレンを排出する構成となっている。ま
た、ドレンセパレータ９の上流側にはイナート蒸気の流
量を調整するためのオリフィス12とイナート蒸気弁８と
が配設される。The drain trap 6 is provided with a drain discharge valve 7 so as to discharge the discharged drain. An orifice 12 for adjusting the flow rate of the inert steam and an inert steam valve 8 are disposed upstream of the drain separator 9.
上記のような構成にあって、給炭機１起動時には、既
に所定の熱空気が流れており、給炭機１起動の信号に応
じてイナート蒸気弁８を開いて蒸気を微粉炭機２内に投
入する。この際、熱空気ダクト３から微粉炭機２に供給
される熱空気量に対して酸素濃度が13〜15％となるよう
にオリフィス12を予め調整しておく。一定時間が経過し
た後に実際に給炭機１が起動し、さらに微粉炭機２内が
微粉炭の爆発濃度上限界を越えたと思われるような一定
時間を経過した後に、イナート蒸気弁８を閉じ、以後は
通常の微粉炭機２の運転に移行する。In the above configuration, when the coal feeder 1 is started, predetermined hot air is already flowing, and the inert steam valve 8 is opened in response to the start signal of the coal feeder 1 to open steam in the pulverized coal feeder 2. To At this time, the orifice 12 is adjusted in advance so that the oxygen concentration becomes 13 to 15% with respect to the amount of hot air supplied from the hot air duct 3 to the pulverized coal machine 2. After a certain period of time, the coal feeder 1 is actually started, and after a certain period of time that seems to have exceeded the explosive concentration limit of the pulverized coal in the pulverized coal machine 2, the inert steam valve 8 is closed. Thereafter, the operation shifts to the ordinary operation of the pulverized coal machine 2.
給炭機１の通常停止過程では、給炭機１の信号停止の
信号によりイナート蒸気弁８を開いて微粉炭機２に供給
される熱空気中の酸素濃度が13〜15％となるようにイナ
ート蒸気を投入する。一定時間が経過した後に給炭機１
が停止し、さらに微粉炭機２内の残炭パージが終了する
一定時間が経過した後に、イナート蒸気弁８を閉じ、熱
空気は停止時の運用に移行する。In the normal stop process of the coal feeder 1, the inert steam valve 8 is opened by the signal of the signal stop of the coal feeder 1 so that the oxygen concentration in the hot air supplied to the pulverized coal feeder 2 becomes 13 to 15%. Add inert steam. Coal feeder 1 after a certain time
Is stopped, and after a lapse of a certain period of time in which the residual coal purge in the pulverized coal machine 2 ends, the inert steam valve 8 is closed, and the hot air shifts to the operation at the time of stop.
また、給炭機１のトリップ時には、トリップ検出によ
りイナート蒸気弁８を開いて微粉炭機２に供給される熱
空気中の酸素濃度が13〜15％となるようにイナート蒸気
を投入する。そして、微粉炭機２内の残炭パージが終了
した後にイナート蒸気弁８を閉じ、移行は停止時の運用
に移行する。Further, when the coal feeder 1 trips, the inert steam valve 8 is opened by trip detection, and inert steam is supplied so that the oxygen concentration in the hot air supplied to the pulverized coal machine 2 becomes 13 to 15%. Then, after the residual coal purge in the pulverized coal machine 2 is completed, the inert steam valve 8 is closed, and the shift is shifted to the operation at the time of stop.
しかるに、微粉炭の爆発については、試験の結果、第
２図に示すような特性が得られており、微粉炭濃度が爆
発濃度下限界以上、上限界以下であっても、酸素濃度が
15％以下であれば爆発には至らないことが確認されてい
る。However, as for the explosion of pulverized coal, the characteristics as shown in Fig. 2 were obtained as a result of the test.
It has been confirmed that if less than 15%, no explosion will occur.
微粉炭機２内の微粉炭濃度は、通常の運転時には爆発
濃度上限界以上であり、爆発に至ることはないが、給炭
機１の起動時、停止時及びトリップ時には、過渡的に爆
発域となる。The pulverized coal concentration in the pulverized coal machine 2 is higher than the upper limit of the explosion concentration during normal operation, and does not lead to an explosion. Becomes
したがって、給炭機１の起動時、停止時及びトリップ
時にのみ、酸素濃度が15％以下となるようにすれば、微
粉炭機２内での爆発を充分に防止することが可能となる
と共に、イナート媒体の消費量を少なくして付帯設備を
必要最小限のものとすることができる。。Therefore, if the oxygen concentration is set to 15% or less only at the time of starting, stopping, and tripping the coal feeder 1, it is possible to sufficiently prevent explosion in the pulverized coal feeder 2, It is possible to reduce the consumption of the inert medium and to minimize the incidental facilities. .
また、酸素濃度を変化させた場合の着火温度について
も試験した結果、第３図に示すように燃焼用の一次空気
となる微粉炭搬送用のガスは、酸素濃度が13％以上であ
れば、空気のみによる搬送の場合と大差ないことがわか
る。In addition, as a result of a test on the ignition temperature when the oxygen concentration was changed, as shown in FIG. 3, the gas for pulverized coal transporting as primary air for combustion had an oxygen concentration of 13% or more. It can be seen that there is not much difference from the case of carrying only by air.
したがって、酸素濃度が13％以上となるようにイナー
ト媒体の投入量を制御すれば、バーナでの不完全燃焼や
失火を招くことなく、燃焼に対する信頼性を維持するこ
とができる。Therefore, if the injection amount of the inert medium is controlled so that the oxygen concentration becomes 13% or more, the combustion reliability can be maintained without incomplete combustion or misfire in the burner.
以上の点を考え合わせ、上述した如く酸素濃度が13％
以上15％以下となるようにイナート蒸気の投入量を制御
するものである。Considering the above points, as mentioned above, the oxygen concentration is 13%
The amount of inert steam input is controlled so as to be 15% or less.
一方、イナート蒸気の投入はCO濃度などの状態の検出
によらず、爆発の恐れのある給炭機１の起動時、停止時
及びトリップ時にのみシーケンシャルに行なうようにし
たので、上記検出装置が不要となり、検出装置のトラブ
ルに伴って信頼性が低下してしまうことを防止できる。On the other hand, the injection of inert steam is not performed by detecting the state of the CO concentration or the like, but is performed sequentially only at the time of starting, stopping, and tripping of the coal feeder 1 which may cause an explosion. Thus, it is possible to prevent the reliability from being lowered due to the trouble of the detection device.
なお、上記実施例ではイナート媒体として蒸気を用い
たが、これに限ること無く、N2やCO2でもよいことは勿
論である。In the above embodiment, steam is used as the inert medium. However, the present invention is not limited to this, and it goes without saying that N 2 or CO 2 may be used.
また、給炭機１の起動時に所定の熱空気量に対して酸
素濃度が13〜15％となるようにイナート上記流量調整オ
リフィス12を予め調整しておくものとしたが、蒸気流量
を計測して制御するようにしてもよい。In addition, when the coal feeder 1 is started, the flow rate adjusting orifice 12 is adjusted in advance so that the oxygen concentration becomes 13 to 15% with respect to a predetermined amount of hot air. Control may be performed.
［発明の効果］ 以上詳記した如く本発明によれば、石炭を粉砕する微
粉炭機内にイナート媒体を投入して該微粉炭機内での酸
素濃度を下げ、微粉炭の爆発を防止する微粉炭機の爆発
防止方法において、微粉炭機内の酸素濃度を13％乃至15
％の範囲内とすべく、微粉炭機に石炭を供給する給炭機
の起動時、停止時及びトリップ時にイナート媒体をシー
ケンシャルに投入するようにしたので、爆発を防止する
ための酸素濃度は充分確保しながらもイナート媒体の消
費量を少なくして付帯設備を必要最小限のものとし、バ
ーナの燃焼の疎外を回避する一方、状態の検出を行なう
機構を排除して該検出機構のトラブルをなくし、装置の
信頼性を向上させることが可能な微粉炭機の爆発防止方
法を提供することができる。[Effects of the Invention] As described above in detail, according to the present invention, pulverized coal for introducing an inert medium into a pulverized coal machine for pulverizing coal to lower the oxygen concentration in the pulverized coal machine and prevent explosion of the pulverized coal. In the method of preventing explosion of pulverized coal, the oxygen concentration in pulverized coal
%, So that the inert medium is charged sequentially when the coal feeder that supplies coal to the pulverizer starts, stops, and trips, so the oxygen concentration to prevent explosion is sufficient. In addition to minimizing the consumption of the inert medium while minimizing incidental equipment while avoiding the alienation of burner combustion, eliminating the mechanism for detecting the state and eliminating the trouble of the detection mechanism Further, it is possible to provide a method for preventing explosion of a pulverized coal machine capable of improving the reliability of the apparatus.
第１図は本発明の一実施例の構成を示す機能ブロック
図、第２図は酸素濃度と微粉炭濃度における爆発の特性
を示す図、第３図は酸素濃度に対応した着火温度の特性
を示す図である。 １……給炭機、２……微粉炭機、３……熱空気ダクト、
４……減圧弁、５……減温器、６……ドレントラップ、
７……ドレン排出弁、８……イナート蒸気弁、９……ド
レンセパレータ、10……バーナ、11……蒸気ライン、12
……オリフィス、13……オリフィス、14……ダンパ。FIG. 1 is a functional block diagram showing a configuration of one embodiment of the present invention, FIG. 2 is a diagram showing characteristics of explosion at oxygen concentration and pulverized coal concentration, and FIG. 3 is a characteristic of ignition temperature corresponding to oxygen concentration. FIG. 1 ... coal feeder, 2 ... pulverizer, 3 ... hot air duct,
4 ... Reducing valve, 5 ... Reducer, 6 ... Drain trap,
7 Drain discharge valve, 8 Inert steam valve, 9 Drain separator, 10 Burner, 11 Steam line, 12
…… orifice, 13 …… orifice, 14 …… damper.
Claims (1)
を投入して該微粉炭機内での酸素濃度を下げ、微粉炭の
爆発を防止する微粉炭機の爆発防止方法において、 微粉炭機に石炭を供給する給炭機の起動時、停止時及び
トリップ時に、微粉炭機内の酸素濃度を13％乃至15％の
範囲内とすべく上記イナート媒体を投入することを特徴
とした微粉炭機の爆発防止方法。1. An explosion prevention method for a pulverized coal machine in which an inert medium is charged into a pulverized coal machine for pulverizing coal to lower the oxygen concentration in the pulverized coal machine and prevent the pulverized coal from exploding. A pulverized coal machine characterized in that the inert medium is introduced so that the oxygen concentration in the pulverized coal machine is within the range of 13% to 15% at the time of starting, stopping, and tripping the coal feeder that supplies coal. Explosion prevention method.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13391890A JP2713640B2 (en) | 1990-05-25 | 1990-05-25 | How to prevent explosion of pulverized coal machine |
| US07/704,324 US5230474A (en) | 1990-05-25 | 1991-05-23 | Mill inert apparatus for coal pulverizer and method for prevention of explosion |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13391890A JP2713640B2 (en) | 1990-05-25 | 1990-05-25 | How to prevent explosion of pulverized coal machine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0429759A JPH0429759A (en) | 1992-01-31 |
| JP2713640B2 true JP2713640B2 (en) | 1998-02-16 |
Family
ID=15116132
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13391890A Expired - Lifetime JP2713640B2 (en) | 1990-05-25 | 1990-05-25 | How to prevent explosion of pulverized coal machine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2713640B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112863116B (en) * | 2020-12-03 | 2023-04-28 | 华能国际电力股份有限公司玉环电厂 | Intelligent diagnosis and alarm display method for deflagration of coal pulverizing system of thermal power plant |
| CN115540573A (en) * | 2021-06-29 | 2022-12-30 | 五矿营口中板有限责任公司 | A safe pulverizing method of high volatile bituminous coal |
-
1990
- 1990-05-25 JP JP13391890A patent/JP2713640B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0429759A (en) | 1992-01-31 |
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