JPH0122806B2 - - Google Patents

Info

Publication number
JPH0122806B2
JPH0122806B2 JP3402283A JP3402283A JPH0122806B2 JP H0122806 B2 JPH0122806 B2 JP H0122806B2 JP 3402283 A JP3402283 A JP 3402283A JP 3402283 A JP3402283 A JP 3402283A JP H0122806 B2 JPH0122806 B2 JP H0122806B2
Authority
JP
Japan
Prior art keywords
slag
kiln
water
wind
molten slag
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
Application number
JP3402283A
Other languages
Japanese (ja)
Other versions
JPS59160525A (en
Inventor
Ryuji Kita
Norisuke Sagara
Tsuneaki Nishikawa
Kaname Arakawa
Kozo Koike
Ryuichi Hori
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kobe Steel Ltd
Original Assignee
Kobe Steel Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Kobe Steel Ltd filed Critical Kobe Steel Ltd
Priority to JP58034022A priority Critical patent/JPS59160525A/en
Publication of JPS59160525A publication Critical patent/JPS59160525A/en
Publication of JPH0122806B2 publication Critical patent/JPH0122806B2/ja
Granted legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B2400/00—Treatment of slags originating from iron or steel processes
    • C21B2400/02—Physical or chemical treatment of slags
    • C21B2400/022—Methods of cooling or quenching molten slag
    • C21B2400/024—Methods of cooling or quenching molten slag with the direct use of steam or liquid coolants, e.g. water
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B2400/00—Treatment of slags originating from iron or steel processes
    • C21B2400/02—Physical or chemical treatment of slags
    • C21B2400/022—Methods of cooling or quenching molten slag
    • C21B2400/026—Methods of cooling or quenching molten slag using air, inert gases or removable conductive bodies
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B2400/00—Treatment of slags originating from iron or steel processes
    • C21B2400/05—Apparatus features
    • C21B2400/052—Apparatus features including rotating parts
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B2400/00—Treatment of slags originating from iron or steel processes
    • C21B2400/05—Apparatus features
    • C21B2400/052—Apparatus features including rotating parts
    • C21B2400/056—Drums whereby slag is poured on or in between
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B2400/00—Treatment of slags originating from iron or steel processes
    • C21B2400/05—Apparatus features
    • C21B2400/062—Jet nozzles or pressurised fluids for cooling, fragmenting or atomising slag
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00—Technologies for solid waste management
    • Y02W30/50—Reuse, recycling or recovery technologies

Description

【発明の詳細な説明】 本発明は、溶融滓の粒状化処理方法、さらに詳
しくは、土木・建築用に用いられる粒状滓の製造
法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for granulating molten slag, and more particularly to a method for producing granular slag used for civil engineering and construction.

従来より、鉄鋼精練工程で発生する溶融滓の処
理、利用に関して、自然冷却による徐冷鉱滓、水
流冷却による水砕鉱滓、蒸気吹付による鉱滓綿な
どが存在する。しかしながら、従来の製造法で
は、(a)処理後の粒状滓の温度が高く、後工程への
搬送が困難であり、処理後の二次冷却を要し、(b)
得られた粒状滓の粒径が大きく、所望の５mm以下
の粒径のものが得られない、あるいは(c)設備が大
きく、広い設置スペースを要する、などの問題点
を有する。 Conventionally, regarding the treatment and utilization of molten slag generated in the steel smelting process, there have been methods such as slow-cooled slag by natural cooling, granulated slag by water jet cooling, and slag cotton by steam blasting. However, in conventional manufacturing methods, (a) the temperature of the granular slag after treatment is high, making it difficult to transport to subsequent processes and requiring secondary cooling after treatment, and (b)
There are problems such as (c) the particle size of the obtained granular slag is large and it is impossible to obtain the desired particle size of 5 mm or less, and (c) the equipment is large and requires a large installation space.

例えば、特開昭50−123502号に開示の溶融滓
（溶融スラグ）の粒状化法では、傾斜した回転ド
ラム内にスラグを供給し、外部よりドラムを冷却
してスラグの粒状化を行なつているが、排出スラ
グの温度は1100℃程度と極めて高く、10mm以下の
粒径のものが５重量％しか得られない。また、特
開昭54−13495号に開示の方法においては、２段
の回転ドラムを用い、最終排出スラグ温度を100
〜200℃としているが、回転ドラム全長が17ｍ
（１段目７ｍ＋２段目10ｍ）、ドラム直径が2.5ｍ
となり、設備が大型化する。さらに、特公昭57−
7094号の開示の風砕においては、スラグ粒径を５
mmφ以下と小さくすることが可能であるが、スラ
グを最低４ｍ、通常10〜15ｍも飛翔させることが
必要であるため設備が大型化する。また、特開昭
48−59079号に開示の方法においては、溶融スラ
グを空気と水の混合物の高速流内に入れて噴射さ
せることによつて内部に密閉された空洞を有する
球状の細粒を得る方法を提供しているが、空気と
水の混合物の流速が約90ｍ／秒と速く、風砕と同
様にスラグ粒子の冷却に必要な飛翔距離が長くな
るため設備が大型化する。また、水砕によりスラ
グを粒状化させる場合は、水／スラグ比を通常５
〜10m3／ｔ程度とする必要があるため、多量の水
を要し、水処理設備が必要となつて、これも設備
が大型化する。 For example, in the method for granulating molten slag disclosed in JP-A-50-123502, slag is fed into an inclined rotating drum, and the drum is cooled from the outside to granulate the slag. However, the temperature of the discharged slag is extremely high at around 1100°C, and only 5% by weight of particles with a particle size of 10 mm or less can be obtained. In addition, in the method disclosed in JP-A No. 54-13495, a two-stage rotating drum is used, and the final discharged slag temperature is adjusted to 100%.
The temperature is ~200℃, but the total length of the rotating drum is 17m.
(1st stage 7m + 2nd stage 10m), drum diameter is 2.5m
As a result, the equipment becomes larger. In addition,
In the wind crushing disclosed in No. 7094, the slag particle size is
Although it is possible to make the size smaller than mmφ, the equipment becomes large because it is necessary to fly the slag at least 4 m, and usually 10 to 15 m. Also, Tokukai Akira
No. 48-59079 discloses a method for obtaining spherical granules with a sealed cavity by injecting molten slag into a high-velocity stream of a mixture of air and water. However, the flow rate of the air and water mixture is as high as approximately 90 m/s, and as with wind crushing, the flying distance required to cool the slag particles is longer, which requires larger equipment. In addition, when granulating slag by water crushing, the water/slag ratio is usually 5.
Since it is necessary to set the amount of water to approximately 10 m 3 /t, a large amount of water is required, and water treatment equipment is required, which also increases the size of the equipment.

ここで、本発明者らは、前記問題点に鑑み鋭意
検討を行なつた結果、回転ドラム（以下、キルン
という）内で空気流と噴霧水により溶融スラグを
分散することにより、設備を大型化せずに排出ス
ラグ温度の低い粒状スラグが得られることを見出
し本発明を完成するに至つた。 As a result of intensive studies in view of the above-mentioned problems, the inventors of the present invention have discovered that by dispersing molten slag in a rotating drum (hereinafter referred to as a kiln) using air flow and spray water, the size of the equipment can be increased. The present invention was completed by discovering that granular slag with a low discharge slag temperature can be obtained without the above.

すなわち、本発明は、噴霧水を含有する空気流
を溶融滓に吹付けて溶融滓を分散し、内部ぬれ壁
状態を形成したキルン内へ該溶融滓を飛散させる
ことからなり、溶融滓と風砕風の比率を600〜
1000Nm3／ｔ、風砕風における水と空気の比率を
0.25〜0.6Kg／Ｎm3、風砕風流速を50〜90ｍ／秒
とした溶融滓の粒状化処理方法を提供するもので
ある。 That is, the present invention consists of dispersing the molten slag by spraying an air stream containing spray water onto the molten slag, and scattering the molten slag into a kiln in which an internal wet wall condition is formed. Increase the ratio of broken wind to 600~
1000Nm 3 /t, the ratio of water and air in wind-breaking wind
The present invention provides a method for granulating molten slag with a flow rate of 0.25 to 0.6 Kg/Nm 3 and a blasting air velocity of 50 to 90 m/sec.

つぎに、本発明方法を実施するための装置の具
体例を図示し、本発明をさらに詳しく説明する。 Next, the present invention will be explained in more detail by illustrating a specific example of an apparatus for carrying out the method of the present invention.

第１図ａおよびｂは、本発明方法に用いられる
粒状滓製造装置の一具体例の概略断面図およびそ
のＡ−Ａ断面図である。該装置は、スラグ落口１
および風砕ノズル２を有する風砕部と、一定速度
で回転する水平に配置されたキルン３からなり、
該キルン３は、排出方向に向け内壁に螺状に形成
されたフイン４を有するとともに、内壁に散水を
行なう複数の散水ノズル５がキルン３前半部に回
転軸と平行に配設されている。ここで、風砕ノズ
ル２は、第２図ａに示すごとく、後方にブロワー
からの空気の吹込口６を有し、かつ側面に水の注
入口７を有したもの、あるいは、第２図ｂに示す
ごとく、注入口７のかわりに水を噴霧するノズル
８を設けたものを用いることができる。 FIGS. 1a and 1b are a schematic cross-sectional view of a specific example of a granular slag manufacturing apparatus used in the method of the present invention, and a cross-sectional view taken along line A-A thereof. The device includes a slag outlet 1
It consists of a wind crushing section having a wind crushing nozzle 2, and a horizontally arranged kiln 3 that rotates at a constant speed,
The kiln 3 has fins 4 spirally formed on the inner wall in the discharge direction, and a plurality of water spray nozzles 5 for spraying water on the inner wall are arranged in the front half of the kiln 3 parallel to the rotation axis. Here, the wind crushing nozzle 2 has an air blowing port 6 from a blower at the rear and a water inlet 7 on the side as shown in FIG. As shown in the figure, a nozzle 8 for spraying water can be used in place of the injection port 7.

第１図ａ，ｂに示す装置を用いて、本発明方法
を実施するには、キルン３内に向けられた風砕ノ
ズル２にブロワー（図示せず）より空気を吹込む
とともに、注水を行ない、キルン３方向に、噴霧
水を含有する空気流（風砕風）を形成させ、該空
気流にスラグ落口１より溶融スラグを落下させ
て、スラグを分散させる。ここで、スラグウール
の発生を抑制するために、第３図に示すように、
風砕ノズル２の周囲にノズル９を設けて噴霧を行
なつてもよい。 To carry out the method of the present invention using the apparatus shown in FIGS. 1a and 1b, air is blown into the blasting nozzle 2 directed into the kiln 3 from a blower (not shown), and water is also injected. , an air stream (crushed air) containing spray water is formed in the direction of the kiln 3, and the molten slag is dropped into the air stream from the slag outlet 1 to disperse the slag. Here, in order to suppress the generation of slag wool, as shown in Figure 3,
A nozzle 9 may be provided around the blasting nozzle 2 for spraying.

キルン３内へ向け飛翔した分散スラグは、キル
ン３により飛散方向に規定され、キルン３内で、
さらに散水ノズル５により水が噴霧されて粒状
化、冷却される。粒状化したスラグは、キルン３
の回転に伴なうフインの働きによつて排出口方向
（図中左方）へ搬出される。さらに、キルンの底
部もまた散水ノズル５によつて噴霧された水によ
りぬれ壁状態になつているため、キルンの底にた
まつた粒状スラグがキルンの排出方向に向けて移
動する間に、底部に形成されたぬれ壁との接触に
よりさらに冷却が促進される。 The dispersed slag that flew towards the inside of the kiln 3 is regulated in the scattering direction by the kiln 3, and within the kiln 3,
Furthermore, water is sprayed by the water spray nozzle 5 to form particles and cool them. The granulated slag is transferred to Kiln 3.
Due to the action of the fins as the fins rotate, it is carried out toward the outlet (to the left in the figure). Furthermore, since the bottom of the kiln is also wetted by the water sprayed by the water spray nozzle 5, while the granular slag accumulated at the bottom of the kiln moves toward the discharge direction of the kiln, the bottom Cooling is further promoted by contact with the wetted wall formed on the surface.

本発明方法において、用いられるスラグとして
は、高炉スラグ、転炉スラグなどがあげられる。
スラグ落口でのスラグ温度は1200〜1500℃、スラ
グと風砕風の比率は、600〜100Nm3／ｔが好まし
い。風砕風における水と空気の比率は、0.25〜
0.6Kg／Ｎm3、風砕風流速は、50〜90ｍ／秒、好
ましくは、65〜75ｍ／秒である。散水ノズルから
の噴霧量は、キルン内壁がぬれ壁状態となる量で
あればよく、1.0〜2.5t／時が好ましい。 In the method of the present invention, examples of the slag used include blast furnace slag and converter slag.
The slag temperature at the slag outlet is preferably 1200 to 1500°C, and the ratio of slag to crushed air is preferably 600 to 100 Nm 3 /t. The ratio of water to air in aeroclastic winds is 0.25~
0.6 Kg/Nm 3 , and the wind speed is 50 to 90 m/sec, preferably 65 to 75 m/sec. The amount of spray from the water nozzle may be such that the inner wall of the kiln becomes wet, and is preferably 1.0 to 2.5 t/hour.

フインの山型断面とキルン内壁とが形成するフ
インの底角は、付着スラグの剥離性から60゜以下
であるのがよい。 The base angle of the fin formed by the chevron-shaped cross section of the fin and the inner wall of the kiln is preferably 60° or less in view of the removability of the adhered slag.

以上述べたごとく、本発明によれば、風砕風中
に噴霧水が混入され、キルン内壁でスプレーが行
なわれるので、キルン内壁がぬれ壁状態となり、
キルンを冷却する必要がなく、装置を小型化し
え、かつキルンの底部におけるぬれ壁とスラグ粒
子の接触により効果的にスラグ粒子の冷却を行な
うことができるため、排出温度100℃以下、粒径
５mm以下の粒状スラグがキルン内壁への付着なし
に製造される。 As described above, according to the present invention, spray water is mixed into the crushed wind and sprayed on the inner wall of the kiln, so that the inner wall of the kiln becomes wet.
There is no need to cool the kiln, the equipment can be made smaller, and the slag particles can be effectively cooled by contact between the wet wall and the slag particles at the bottom of the kiln, so the discharge temperature is below 100℃ and the particle size is 5 mm. The following granular slag is produced without adhesion to the inner walls of the kiln.

つぎに本発明を実施例により、さらに詳しく説
明する。 Next, the present invention will be explained in more detail with reference to Examples.

実施例 第１図に示す装置を用いて、以下の条件により
粒状スラグの製造を行なつた。Example Using the apparatus shown in FIG. 1, granular slag was manufactured under the following conditions.

スラグ処理流量 300Kg／分 スラグ処理前温度 1265℃ キルン仕様 1346mmφ×4000mmＬ キルン回転数 5r.p.m スプレー量（散水ノズル） 1.5m3／時 風砕風量 15000Nm3／時 風砕風流速 70ｍ／秒 風砕風中の噴霧水量 4.5m3／時 水／スラグ 0.33m3／ｔ 得られた粒状スラグは、排出温度50〜80℃、ス
ラグ粒度５mm以下が95％以上、スラグウール０％
の優れた粒状スラグであつた。Slag treatment flow rate 300Kg/min Temperature before slag treatment 1265℃ Kiln specifications 1346mmφ×4000mmL Kiln rotation speed 5r.pm Spray amount (water nozzle) 1.5m 3 /hour Crushed air volume 15000Nm 3 /hour Crushed wind flow velocity 70m/sec Wind crushing Amount of water sprayed in the wind: 4.5 m 3 /hour Water / slag: 0.33 m 3 /t The obtained granular slag has a discharge temperature of 50 to 80°C, 95% or more of slag particle size of 5 mm or less, and 0% of slag wool.
It was an excellent granular slag.

【図面の簡単な説明】[Brief explanation of drawings]

第１図ａは、本発明方法に用いられる溶融滓処
理装置の一具体例の概略縦断面図、第１図ｂは、
そのＡ−Ａ断面図、第２図ａ，ｂはいずれも風砕
ノズルの構造を示す断面図、第３図は、風砕部の
一具体例を示す概略図である。 図中の主な符号は、つぎのとおりである。２…
…風砕ノズル、３……キルン、４……フイン、５
……散水ノズル、６……吹込口、７……注入口、
８……ノズル。 FIG. 1a is a schematic vertical cross-sectional view of a specific example of a molten slag processing apparatus used in the method of the present invention, and FIG. 1b is a
The AA sectional view and FIGS. 2a and 2b are both sectional views showing the structure of the wind crushing nozzle, and FIG. 3 is a schematic diagram showing a specific example of the wind crushing part. The main symbols in the figure are as follows. 2...
...Wind crushing nozzle, 3...Kiln, 4...Fin, 5
...Water nozzle, 6...Inlet, 7...Inlet,
8...Nozzle.

Claims (1)

【特許請求の範囲】[Claims] １ 噴霧水を含有する空気流を溶融滓に吹付けて
溶融滓を分散し、内部ぬれ壁状態を形成したキル
ン内へ該溶融滓を飛散させることからなり、溶融
滓と風砕風の比率を600〜1000Nm3／ｔ、風砕風
における水と空気の比率を0.25〜0.6Kg／Ｎm3、
風砕風流速を50〜90ｍ／秒としたことを特徴とす
る溶融滓の粒状化処理方法。1 The method consists of dispersing the molten slag by blowing an air stream containing spray water onto the molten slag, and scattering the molten slag into the kiln which has formed an internal wet wall condition, and the ratio of the molten slag to the wind debris is controlled. 600 to 1000Nm 3 /t, the ratio of water and air in the wind to 0.25 to 0.6Kg/Nm 3 ,
A method for granulating molten slag, characterized in that the flow velocity of the blasting wind is 50 to 90 m/sec.
JP58034022A 1983-03-01 1983-03-01 Granulating method of molten slag Granted JPS59160525A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP58034022A JPS59160525A (en) 1983-03-01 1983-03-01 Granulating method of molten slag

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP58034022A JPS59160525A (en) 1983-03-01 1983-03-01 Granulating method of molten slag

Publications (2)

Publication Number Publication Date
JPS59160525A JPS59160525A (en) 1984-09-11
JPH0122806B2 true JPH0122806B2 (en) 1989-04-27

Family

ID=12402746

Family Applications (1)

Application Number Title Priority Date Filing Date
JP58034022A Granted JPS59160525A (en) 1983-03-01 1983-03-01 Granulating method of molten slag

Country Status (1)

Country Link
JP (1) JPS59160525A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003515722A (en) * 1999-11-30 2003-05-07 ビレーラ、ビビアン・バスコンセロス Apparatus and process for extracting heat to solidify molten material particles

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JPS61136942A (en) * 1984-12-06 1986-06-24 株式会社神戸製鋼所 Slag treatment apparatus
AU2000247847A1 (en) * 2000-05-19 2001-11-26 Oksoo Oh Method for recovering useful metal from slag generated in steel-making process while treating the slag
JP5338095B2 (en) * 2008-03-20 2013-11-13 Ｊｆｅスチール株式会社 Slag cooling method
CN102527920B (en) * 2012-02-28 2013-11-06 河南科技大学 Preparation method for molding sand used for non-ferrous metal
CN102864252B (en) * 2012-09-13 2014-02-19 清华大学 Slag granulation and sensible heat recovery method and system
CN102864254B (en) * 2012-09-13 2014-04-02 清华大学 Method and system for molten slag granulation and sensible heat recovery
CN107858461B (en) * 2017-11-30 2020-02-07 攀钢集团攀枝花钢铁研究院有限公司 Method for online granulating and collecting molten titanium carbide slag

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4859079A (en) * 1971-11-27 1973-08-18
JPS5010283A (en) * 1973-06-02 1975-02-01
JPS5413495A (en) * 1977-07-01 1979-01-31 Mitsubishi Heavy Ind Ltd Continuously recovering equipment for heat of molten slag

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4859079A (en) * 1971-11-27 1973-08-18
JPS5010283A (en) * 1973-06-02 1975-02-01
JPS5413495A (en) * 1977-07-01 1979-01-31 Mitsubishi Heavy Ind Ltd Continuously recovering equipment for heat of molten slag

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003515722A (en) * 1999-11-30 2003-05-07 ビレーラ、ビビアン・バスコンセロス Apparatus and process for extracting heat to solidify molten material particles

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