JPH0149776B2 - - Google Patents
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- Publication number
- JPH0149776B2 JPH0149776B2 JP60126335A JP12633585A JPH0149776B2 JP H0149776 B2 JPH0149776 B2 JP H0149776B2 JP 60126335 A JP60126335 A JP 60126335A JP 12633585 A JP12633585 A JP 12633585A JP H0149776 B2 JPH0149776 B2 JP H0149776B2
- Authority
- JP
- Japan
- Prior art keywords
- furnace
- reduction furnace
- exhaust gas
- fluidized bed
- smelting
- 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.)
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- Manufacture And Refinement Of Metals (AREA)
- Manufacture Of Iron (AREA)
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は鉄鋼、合金鉄、または非鉄金属などの
溶融金属の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing molten metal such as steel, ferroalloy, or nonferrous metal.
良質のコークスや焼結鉱などを原料として用い
る高炉による銑鉄製造法や電力をエネルギーとし
て用いる電気炉による合金鉄の製造法などの旧来
の技術に代つて、溶融還元法による溶融金属製造
プロセスの開発が進められている。このようなプ
ロセスでは、溶融還元炉から多量の排ガスが発生
するので、これを有効利用することによつてエネ
ルギー消費量の減少を図りコストを低減するため
に、溶融還元炉の排ガスを鉱石の予備還元に有効
に利用することが必要である。
Developing a molten metal production process using the smelting reduction method to replace traditional technologies such as the production of pig iron using a blast furnace using high-quality coke and sintered ore as raw materials, and the production method of ferroalloy using electric furnaces using electricity as energy. is in progress. In such a process, a large amount of exhaust gas is generated from the smelting reduction furnace, so in order to reduce energy consumption and costs by using this effectively, the exhaust gas from the smelting reduction furnace is used as a reserve for ore. It is necessary to use it effectively for reduction.
このような溶融金属製造プロセスに用いる溶融
還元炉には、転炉型のバツチ操業炉と高炉型また
は流動層型の連続操業炉の２種の炉がある。他方
予備還元炉としては、ロータリーキルン、シヤフ
ト炉、流動層炉などがある。 There are two types of smelting reduction furnaces used in such a molten metal production process: a converter type batch operation furnace and a blast furnace type or fluidized bed type continuous operation furnace. On the other hand, examples of the preliminary reduction furnace include a rotary kiln, a shaft furnace, and a fluidized bed furnace.
溶融金属製造プロセスとしてはこれらの溶融還
元炉と予備還元炉の組み合わせによつて、数種類
のプロセスを構成することができる。転炉とロー
タリーキルンとの組み合わせプロセスについては
特開昭59−113158、特開昭59−145758、特開昭60
−2613、特開昭60−2614などの技術が開示されて
いる。 Several types of molten metal manufacturing processes can be configured by combining these smelting reduction furnaces and preliminary reduction furnaces. Regarding the combined process of converter and rotary kiln, see JP-A-59-113158, JP-A-59-145758, JP-A-60.
Techniques such as JP-A-2613 and JP-A-60-2614 have been disclosed.
また、流動層型の溶融還元炉とシヤフト炉型の
予備還元炉との組み合わせについては特開昭57−
120607が開示されている。 In addition, regarding the combination of a fluidized bed type smelting reduction furnace and a shaft type pre-reduction furnace, Japanese Patent Application Laid-Open No. 57-
120607 has been disclosed.
本発明はこれらの従来技術とは異なり、溶融還
元炉と予備還元炉との組み合わせに係るプロセス
の新規な技術を提供しようとするものである。
The present invention differs from these conventional techniques in that it provides a new technique for a process involving a combination of a melting reduction furnace and a pre-reduction furnace.
溶融還元炉の排ガスは、
ガスの温度レベルが高く、例えば1000〜1900
℃である。 The exhaust gas from the smelting reduction furnace has a high gas temperature level, e.g.
It is ℃.
ガス組成としてCO2が多く、また高H2Oであ
る。 The gas composition is high in CO 2 and high in H 2 O.
ガス中に大量のダストを含んでいる。 The gas contains a large amount of dust.
ガス圧が低い。 Gas pressure is low.
などの特性をもち、従来このような溶融還元炉の
排ガスを予備還元炉に利用する場合には、溶融還
元炉と予備還元炉の中間に高温サイクロンを設け
ていたので次の問題があつた。Conventionally, when the exhaust gas from such a smelting reduction furnace was used in a pre-reduction furnace, a high temperature cyclone was installed between the smelting reduction furnace and the pre-reduction furnace, which caused the following problems.
(a) 熱効率が低い。(a) Low thermal efficiency.
(b) 溶融還元炉の排ガスの処理、例えばCO2や
H2Oの除去、昇圧などに費用がかかる。(b) Treatment of flue gas from smelting reduction furnaces, such as CO 2 and
Removal of H 2 O, pressurization, etc. are expensive.
(c) 高温サイクロンにダストが付着する。(c) Dust adheres to the high temperature cyclone.
(d) 高温サイクロンでの除塵が十分にできず、予
備還元炉の分散板が目詰りを起こし、操業が停
止することがある。(d) Dust removal using the high-temperature cyclone may not be sufficient and the dispersion plate of the pre-reduction furnace may become clogged, resulting in a shutdown of the operation.
(e) 高温のガスが予備還元炉に供給されるため予
備還元炉内で鉱石の焼結が起こり、予備還元炉
からの鉱石排出が困難となる。(e) Since high-temperature gas is supplied to the pre-reduction furnace, sintering of the ore occurs within the pre-reduction furnace, making it difficult to discharge the ore from the pre-reduction furnace.
本発明はこれらの問題点を解決した、溶融金属
の製造方法を提供することを目的とする。 An object of the present invention is to provide a method for manufacturing molten metal that solves these problems.
本発明は、還元剤として安価な粉石炭を用いる
ことのできる溶融還元炉を用い、この溶融還元炉
から大量に発生する排ガスを粉鉱石の予備還元に
有効に利用しエネルギーコストを低減するため
に、溶融還元炉と予備還元炉との間に、炭材を含
む粒子を充填してなる流動層調整炉を設け、この
調整炉に溶融還元炉の排ガスを供給して精製し、
この精製後のガスを予備還元炉に供給する技術手
段を講じた。
The present invention uses a smelting reduction furnace that can use inexpensive pulverized coal as a reducing agent, and effectively utilizes a large amount of exhaust gas generated from this smelting reduction furnace for preliminary reduction of fine ore to reduce energy costs. A fluidized bed conditioning furnace filled with particles containing carbonaceous material is provided between the smelting reduction furnace and the preliminary reduction furnace, and the exhaust gas from the smelting reduction furnace is supplied to this conditioning furnace for purification.
A technical measure was taken to supply this purified gas to the preliminary reduction furnace.
流動層調整炉は溶融還元炉の排ガスの温度、ガ
ス組成およびダスト含有量を予備還元に適するよ
うに調整する作用をなすものである。
The fluidized bed adjustment furnace functions to adjust the temperature, gas composition, and dust content of the exhaust gas from the smelting reduction furnace so that it is suitable for preliminary reduction.
溶融還元炉の排ガス中のアルカリ成分やSiOな
どの有害成分は流動層調整炉内におけるガス温度
低下により、流動層調整炉内の流動媒体の表面に
凝縮しガス中から除去することができる。 Harmful components such as alkali components and SiO in the exhaust gas of the smelting reduction furnace can be condensed on the surface of the fluidized medium in the fluidized bed conditioning furnace and removed from the gas by lowering the gas temperature in the fluidized bed conditioning furnace.
また、排ガス中のダストの１部も流動媒体に捕
捉される。 A portion of the dust in the exhaust gas is also trapped in the fluidizing medium.
さらに炭材を含む粒子を充填し、これを流動媒
体として流動層を形成すれば排ガス中のCO2、
H2Oが炭材と反応し、
CO2＋Ｃ→2CO
H2O＋Ｃ→CO＋H2
のリフオーミング反応によつてCO2、H2Oが減少
シ、CO、H2が増加する。この反応は吸熱反応な
のでガス温度も低下する。 Furthermore, if particles containing carbonaceous material are filled and a fluidized bed is formed using this as a fluidizing medium, CO 2 in exhaust gas,
H 2 O reacts with the carbonaceous material, and CO 2 and H 2 O decrease and CO and H 2 increase due to the reforming reaction of CO 2 +C→2CO H 2 O+C→CO+ H 2 . Since this reaction is endothermic, the gas temperature also decreases.
またCO2とH2Oが減少し、CO、H2が増加する
ことにより、予備還元炉における還元反応速度が
向上する。 Furthermore, the reduction reaction rate in the preliminary reduction furnace is improved by decreasing CO 2 and H 2 O and increasing CO and H 2 .
本発明の実施例の構成を示す系統図を第１図に
示した。溶融還元炉１と予備還元炉２が直列に結
合され、そのガス系路に流動層調整炉３が介装さ
れている。
A system diagram showing the configuration of an embodiment of the present invention is shown in FIG. A melting reduction furnace 1 and a preliminary reduction furnace 2 are connected in series, and a fluidized bed conditioning furnace 3 is interposed in the gas line.
溶融還元炉１の形式としては、金属浴型、転炉
型、コークス充填層型および流動層型などがあ
る。 The types of the melting reduction furnace 1 include a metal bath type, a converter type, a coke packed bed type, and a fluidized bed type.
溶融還元炉１には予備還元鉱石４、石炭または
コークスなどの炭材５，６、酸素または空気など
の酸素含有気体７が供給され、排出口８から溶融
金属と溶融スラグが排出され、炉頂からは高温の
溶融還元炉排ガス９が排出される。 The smelting reduction furnace 1 is supplied with pre-reduced ore 4, carbonaceous materials 5, 6 such as coal or coke, and oxygen-containing gas 7 such as oxygen or air, and molten metal and molten slag are discharged from the discharge port 8, and the melted slag is discharged from the top of the furnace. High-temperature smelting and reduction furnace exhaust gas 9 is discharged from.
予備還元鉱石４は粉状でも塊状でもよく、還元
率は鉄鉱石では50〜90％程度であり、予備還元炉
２から高温で排出し、溶融還元炉へホツトチヤー
ジすることもでき、また、一旦冷却してから供給
することもできる。 The pre-reduced ore 4 may be in the form of powder or lumps, and the reduction rate is about 50 to 90% for iron ore. It can also be supplied afterwards.
予備還元炉２は塊状鉱石の場合はシヤフト炉、
粉状鉱石の場合は流動層を用いることができる。
溶融還元炉の排ガス９は1000〜1900℃の高温であ
り、多量のダストを含有するほか、SiOやアルカ
リ成分等も含有する。還元ガス成分としてCOと
H2を含むが、還元を阻止する成分としてCO2と
H2Oを含有する。 The preliminary reduction furnace 2 is a shaft furnace in the case of lump ore,
In the case of powdered ore, a fluidized bed can be used.
The exhaust gas 9 from the melting reduction furnace has a high temperature of 1000 to 1900°C, and contains a large amount of dust, as well as SiO, alkali components, and the like. With CO as a reducing gas component
Contains H2 , but with CO2 as a component to prevent reduction.
Contains H2O .
流動層調整炉３に石炭やコークス等の炭材１１
を装入して、溶融還元炉排ガス９を導入して流動
層を形成する。溶融還元炉排ガス中のCO2とH2O
は流動層調整炉３内の石炭やコークス中のＣと反
応してCOとH2を生成する。この反応は吸熱反応
であり、溶融還元炉排ガス９中のCO2とH2Oが多
い場合には、流動層温度が下りすぎるため、空気
または酸素１２を吹込んで炭材の一部を燃焼して
流動層を必要な温度に維持する。溶融還元炉排ガ
ス９中のアルカリやSiO等の有害成分は流動層内
の粒子１３の表面に凝縮して除去され、またダス
トも粘着性のある粒子は流動層内の粒子１３に捕
捉される。有害成分の除去効果を上げるために石
灰等を炭材１１に混合することもできる。調整炉
３から排出される炭材５は溶融還元炉で用いるこ
とにより有効利用することができる。 Carbon material 11 such as coal or coke is placed in the fluidized bed conditioning furnace 3.
is charged, and the smelting reduction furnace exhaust gas 9 is introduced to form a fluidized bed. CO 2 and H 2 O in smelting reduction furnace exhaust gas
reacts with C in the coal and coke in the fluidized bed conditioning furnace 3 to generate CO and H 2 . This reaction is an endothermic reaction, and if there are a lot of CO 2 and H 2 O in the smelting reduction furnace exhaust gas 9, the temperature of the fluidized bed will drop too much, so air or oxygen 12 is blown in to burn part of the carbonaceous material. to maintain the fluidized bed at the required temperature. Harmful components such as alkali and SiO in the smelting reduction furnace exhaust gas 9 are condensed on the surfaces of the particles 13 in the fluidized bed and removed, and dust and sticky particles are captured by the particles 13 in the fluidized bed. Lime or the like can also be mixed into the carbon material 11 in order to increase the effect of removing harmful components. The carbon material 5 discharged from the conditioning furnace 3 can be effectively utilized by using it in a melting reduction furnace.
調整炉排ガス１４は有害成分とダスト量が減少
し、CO2やH2Oの低下により還元力が増加し、ガ
ス温度も調整されて排出されるので、予備還元炉
２へ導入して効率よく鉱石１５を予備還元炉する
ことができる。 The regulating furnace exhaust gas 14 has a reduced amount of harmful components and dust, an increased reducing power due to a decrease in CO 2 and H 2 O, and the gas temperature is also adjusted before being discharged, so it can be introduced into the pre-reducing furnace 2 and efficiently processed. The ore 15 can be subjected to a preliminary reduction furnace.
次に具体例について述べると次の通りである。
転炉型の溶融還元炉と流動層予備還元炉とを用い
て鉄鉱石の溶融還元を行つた。従来、溶融還元炉
から予備還元炉へのガス系路にはサイクロンを介
装していてが、詰まりその他のトラブルが多かつ
た。そこで本発明方法を適用し、溶融還元炉の排
ガスを流動層調整炉を通過させて予備還元炉に導
入した。 Next, a specific example will be described as follows.
Iron ore was smelted and reduced using a converter-type smelting reduction furnace and a fluidized bed pre-reduction furnace. Conventionally, a cyclone was installed in the gas line from the smelting reduction furnace to the preliminary reduction furnace, but this often caused clogging and other problems. Therefore, the method of the present invention was applied, and the exhaust gas from the smelting reduction furnace was passed through a fluidized bed conditioning furnace and introduced into the pre-reduction furnace.
鉄鉱石：種類；ブラジルMBR鉱石
供給量；740Kg／hr
予備還元炉：内径1.2ｍ
溶融還元炉：内径1.2ｍ
流動層調整炉：内径１ｍ
炭材種類；粉コークス
粉コークス供給量；60Kg／hr
粉コークス排出量；20Kg／hr
溶融還元排ガス：
流量：760Nm3／hr
組成：CO；53.4％
H2；24.3％
CO2；13.6％
H2O；6.1％
ダスト；53ｇ／Ｎm3
温度：1600℃
調整炉排ガス：
流量：840Nm3／hr
組成：CO；64.7％
H2；25.5％
CO2；6.5％
H2O；2.6％
ダスト；21ｇ／Ｎm3
温度：950℃
予備還元炉排ガス：
流量：860Nm3／hr
組成：CO；46.0％
H2；16.9％
CO2；23.4％
H2O；11.0％
温度：800℃
予備還元鉱石：
生産量：590Kg／hr
還元率：73％
溶融鉄生産量：11ton／hr
上記本発明の実施例により、予備還元鉱石の供
給量、還元率ともに上昇し、本発明の適用以前に
比し、同一の装置で20〜30％の能率向上を示し
た。また、サイクロンの詰まりトラブル等が皆無
となり、長時間の安定操業が可能となつた。Iron ore: Type: Brazilian MBR ore Supply amount: 740Kg/hr Pre-reduction furnace: 1.2m inner diameter Melting reduction furnace: 1.2m inner diameter Fluidized bed conditioning furnace: 1m inner diameter Carbon material type: Coke powder Coke powder supply amount: 60Kg/hr Powder Coke emission: 20Kg/hr Melting reduction exhaust gas: Flow rate: 760Nm 3 /hr Composition: CO; 53.4% H 2 ; 24.3% CO 2 ; 13.6% H 2 O; 6.1% Dust; 53g/Nm 3 Temperature: 1600℃ Adjustment Furnace exhaust gas: Flow rate: 840Nm 3 /hr Composition: CO; 64.7% H 2 ; 25.5% CO 2 ; 6.5% H 2 O; 2.6% Dust; 21g/Nm 3 Temperature: 950℃ Pre-reduction furnace exhaust gas: Flow rate: 860Nm 3 /hr Composition: CO; 46.0% H 2 ; 16.9% CO 2 ; 23.4% H 2 O; 11.0% Temperature: 800℃ Pre-reduced ore: Production: 590Kg/hr Reduction rate: 73% Molten iron production: 11ton/ hr According to the above embodiment of the present invention, both the supply amount of pre-reduced ore and the reduction rate increased, and the efficiency was improved by 20 to 30% with the same equipment compared to before the application of the present invention. In addition, there were no problems such as clogging of the cyclone, and stable operation for long periods of time became possible.
本発明の効果を列挙すると次の通りである。 The effects of the present invention are listed below.
(1) 溶融還元炉排ガス中に含まれる有害成分の除
去およびダストの減少により、予備還元炉のガ
ス分散板の目詰りなどのダストラブルが解消さ
れた。(1) Dust troubles such as clogging of the gas distribution plate in the pre-reduction furnace have been resolved by removing harmful components and reducing dust contained in the flue gas of the smelter reduction furnace.
(2) 溶融還元炉の排ガス中のCO2やH2Oを減少さ
せてから予備還元炉へ導入することにより、予
備還元反応速度が増加する。(2) The preliminary reduction reaction rate is increased by reducing CO 2 and H 2 O in the exhaust gas of the smelting reduction furnace before introducing it into the preliminary reduction furnace.
(3) 溶融還元炉の温度を低下してから予備還元炉
へ導入することにより、予備還元炉内の過熱に
よる粒子の焼結などのトラブルを防止すること
ができる。(3) By lowering the temperature of the smelting reduction furnace before introducing it into the preliminary reduction furnace, troubles such as sintering of particles due to overheating in the preliminary reduction furnace can be prevented.
第１図は、本発明の実施例のフローシートであ
る。
１……溶融還元炉、２……予備還元炉、３……
流動層調整炉、４……予備還元鉱石、９……溶融
還元炉排ガス、１４……調整炉排ガス。
FIG. 1 is a flow sheet of an embodiment of the present invention. 1... Melting reduction furnace, 2... Preliminary reduction furnace, 3...
Fluidized bed conditioning furnace, 4...preliminary reduced ore, 9... smelting reduction furnace exhaust gas, 14... conditioning furnace exhaust gas.
Claims (1)
溶融還元炉の排ガスを予備還元用ガスとして予備
還元炉に供給して鉄鉱石を予備還元し、予備還元
された鉱石を溶融還元炉に供給して溶融金属を製
造する方法において、 溶融還元炉と予備還元炉の間に流動層調整炉を
設け、該流動層調整炉には溶融還元炉に装入すべ
き炭材を含む粒子を充填し、溶融還元炉排ガスを
該流動層調整炉を通すことにより溶融還元炉排ガ
スを精製してから予備還元炉に供給することを特
徴とする溶融金属の製造方法。[Claims] 1. A melting reduction furnace and a preliminary reduction furnace are connected in series,
In a method for producing molten metal by supplying the exhaust gas of the smelting reduction furnace to the smelting reduction furnace as a pre-reduction gas to pre-reduce iron ore and supplying the pre-reduced ore to the smelting reduction furnace, the smelting reduction furnace and A fluidized bed conditioning furnace is provided between the preliminary reduction furnaces, the fluidized bed conditioning furnace is filled with particles containing carbonaceous material to be charged into the smelting reduction furnace, and the smelting reduction furnace exhaust gas is passed through the fluidized bed conditioning furnace. A method for producing molten metal, which comprises purifying smelting reduction furnace exhaust gas and then supplying it to a preliminary reduction furnace.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12633585A JPS61284510A (en) | 1985-06-12 | 1985-06-12 | Production of molten metal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12633585A JPS61284510A (en) | 1985-06-12 | 1985-06-12 | Production of molten metal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61284510A JPS61284510A (en) | 1986-12-15 |
| JPH0149776B2 true JPH0149776B2 (en) | 1989-10-26 |
Family
ID=14932629
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12633585A Granted JPS61284510A (en) | 1985-06-12 | 1985-06-12 | Production of molten metal |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61284510A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106636659A (en) * | 2016-10-17 | 2017-05-10 | 中国有色集团（广西）平桂飞碟股份有限公司 | Method for smelting tin from tin smelting powder residue |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2623269B2 (en) * | 1987-12-08 | 1997-06-25 | 川崎重工業株式会社 | Method of adjusting gas properties for preliminary reduction in smelting reduction |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE395714B (en) * | 1974-02-20 | 1977-08-22 | Skf Ind Trading & Dev | METHODS AND DEVICES FOR MANUFACTURE OF METALS FROM OXIDIC MATERIAL |
| DE3318005C2 (en) * | 1983-05-18 | 1986-02-20 | Klöckner CRA Technologie GmbH, 4100 Duisburg | Process for making iron |
-
1985
- 1985-06-12 JP JP12633585A patent/JPS61284510A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106636659A (en) * | 2016-10-17 | 2017-05-10 | 中国有色集团（广西）平桂飞碟股份有限公司 | Method for smelting tin from tin smelting powder residue |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61284510A (en) | 1986-12-15 |
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