KR20030000881A - A Method for Removing Reclained lump steel on the Converter Throat Using Nitrogen Blowing - Google Patents

A Method for Removing Reclained lump steel on the Converter Throat Using Nitrogen Blowing Download PDF

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Publication number
KR20030000881A
KR20030000881A KR1020010037040A KR20010037040A KR20030000881A KR 20030000881 A KR20030000881 A KR 20030000881A KR 1020010037040 A KR1020010037040 A KR 1020010037040A KR 20010037040 A KR20010037040 A KR 20010037040A KR 20030000881 A KR20030000881 A KR 20030000881A
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South Korea
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converter
furnace
slag
nitrogen
lance
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KR1020010037040A
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Korean (ko)
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KR100758435B1 (en
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박태윤
김영섭
윤병한
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주식회사 포스코
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    • 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
    • C21C5/42—Constructional features of converters
    • C21C5/46—Details or accessories
    • C21C5/4693—Skull removal; Cleaning of the converter mouth
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D25/00—Devices or methods for removing incrustations, e.g. slag, metal deposits, dust; Devices or methods for preventing the adherence of slag
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D3/00—Charging; Discharging; Manipulation of charge
    • F27D3/16—Introducing a fluid jet or current into the charge

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Carbon Steel Or Casting Steel Manufacturing (AREA)

Abstract

PURPOSE: A method for removing metal adhered onto the mouth of a converter using nitrogen is provided to reduce time required for removing metal adhered onto the mouth, thereby smoothly perform converter operation accordingly by simply removing metal adhered onto the mouth of the converter. CONSTITUTION: In a series of converter(1) refining method comprising the processes of charging raw materials into the converter, blowing oxygen into the charged raw materials through a lance(3), and slagging off slag(2) in the converter after tapping the molten steel refined by blowing, the method for removing metal adhered onto the mouth of a converter using nitrogen is characterized in that slag(2) scattered by blowing nitrogen into slag on the upper part of molten steel(6) through the lance before tapping the molten steel(6) is coated on the surface of the mouth of the converter(1) to a thickness of 30 mm, wherein the blowing of nitrogen is performed at a position that is 2500 to 4000 mm distanced from the bottom of bricks of the converter.

Description

질소를 이용한 전로 노구 부착지금의 제거방법{A Method for Removing Reclained lump steel on the Converter Throat Using Nitrogen Blowing}A Method for Removing Reclained lump steel on the Converter Throat Using Nitrogen Blowing}

본 발명은 전로 노구에 부착된 지금을 제거하는 방법에 관한 것으로서, 보다 상세하게는 질소 취입에 의해 전로 노구 표면에 슬래그 코팅을 유도하는 새로운 방식을 통해 전로 노구에 부착되는 지금을 매우 용이하게 제거하는 방법에 관한 것이다.The present invention relates to a method for removing the now attached to the converter furnace, and more particularly to remove the now attached to the converter furnace through a novel method of inducing a slag coating on the surface of the converter furnace by nitrogen injection. It is about a method.

일반적으로 제강 공정은 전로 내에 원료를 장입, 산소 취련, 출강 및 슬래그배제 과정의 순서로 이루어진다. 이러한 일련의 제강공정중 산소 취련 작업은 전로 내의 용선 중에 존재하는 불순물을 제거하는 과정이다. 상기 산소 취련 작업 과정에서는 용선으로부터 미세한 철립이 발생되어 비산하는 현상이 일어난다. 비산된 철립은 전로를 빠져나가다가 온도가 낮은 전로의 내벽 또는 노구에 부착되어 지금을 형성한다. 용철은 전로의 내벽, 특히 전로의 노구에 소착되면 분리가 어렵다.Generally, the steelmaking process consists of charging raw materials in the converter, oxygen blowing, tapping and slag removal. Oxygen blowing operation of this series of steelmaking process is to remove impurities present in the molten iron in the converter. In the oxygen blowing operation process, fine iron grains are generated and scattered from the molten iron. The scattered iron grains exit the converter and attach to the inner wall or furnace of the lower temperature converter to form a now. The molten iron is difficult to separate when it is seized on the inner wall of the converter, especially the furnace furnace of the converter.

그래서, 대부분의 제강공장에서는 전로 정련을 행하기 앞서 전로의 내벽에 지금이 부착되지 않도록 도1과 같이 전로(1)에 소량의 슬래그(2)를 남겨둔 상태에서 랜스(3)를 통해 질소를 분사시켜 전로의 내벽(1a)을 슬래그로 코팅하였다. 비산된 슬래그는 전로의 내벽에 부착되더라도 냉각중 박리되어 전로와의 분리가 용이하다. 질소 분사에 의한 슬래그 코팅은 지금 방지에 매우 유용하다. 그러나, 전로 내벽이 아닌 노구에 부착된 지금의 제거에는 전혀 효과가 없었다. 이러한 이유로 기존에는 도2와 같이, 전로(1)를 경동시킨 상태에서 전로에 고철을 장입할 때 사용하는 장입슈트(4)를 이용하여 노구(1b)의 지금(5)을 아래에서 걸거나 위에서 누르는 방식으로 제거하였다.Therefore, in most steel mills, nitrogen is injected through the lance 3 while leaving a small amount of slag 2 in the converter 1 as shown in FIG. 1 so that the current is not adhered to the inner wall of the converter before the converter is refined. The inner wall 1a of the converter was coated with slag. Even though the slag scattered is attached to the inner wall of the converter, it is easily peeled off during cooling, so that the slag is easily separated from the converter. Slag coating by nitrogen injection is now very useful for prevention. However, there was no effect at all on the removal of the current attached to the furnace, not the converter inner wall. For this reason, as shown in Fig. 2, the current 5 of the furnace 1b is hung from below or from the top using the charging chute 4 used to load the scrap metal into the converter while the converter 1 is tilted. It was removed by pressing.

그러나, 전로의 노구의 재질은 주철재이기 때문에 전로의 노구에 부착된 지금은 상기 방법으로는 잘 제거되지 않으며 제거 작업 자체가 장시간을 요하게 된다. 더욱이 상기 방법은 장입슈트 등 설비를 손상시킴으로써 조업을 중단시키는 문제를 유발시킬 수도 있다.However, since the material of the furnace furnace of the converter is cast iron, it is hardly removed by the above method now attached to the furnace furnace of the converter, and the removal operation itself takes a long time. Moreover, the method may cause the problem of stopping the operation by damaging the equipment such as the charging chute.

본 발명의 목적은 전로 노구 표면을 슬래그 코팅하여 노구에 부착되는 지금을 용이하게 제거함에 있다.An object of the present invention is to easily remove the now adhered to the furnace by slag coating the converter furnace surface.

본 발명의 다른 목적은 전로 노구에 부착된 지금을 간단히 제거하므로써, 노구 부착지금 제거작업시간을 줄이고 이에 따라 전로 조업을 원활하게 행하는데 있다.Another object of the present invention is to reduce the time required to remove the furnace fittings now by simply removing the now attached to the converter furnace, thereby smoothly operating the converter.

도1은 전로 정련에 앞서 전로의 내벽에 슬래그 코팅을 행하는 전로의 모식도.1 is a schematic diagram of a converter for performing slag coating on the inner wall of the converter prior to converter refining.

도2는 전로 노구에 부착된 지금을 제거하는 종래방법을 설명하기 위한 모식도.Figure 2 is a schematic diagram for explaining a conventional method for removing the now attached to the converter furnace.

도3은 본 발명에 따라 전로 노구에 슬래그 코팅을 행하는 전로의 모식도.Figure 3 is a schematic diagram of a converter for slag coating the converter furnace in accordance with the present invention.

* 도면의 주요부분에 대한 부호의 설명 *Explanation of symbols on the main parts of the drawings

1 ..... 전로2 ..... 슬래그3 ..... 랜스1 ..... Converter 2 ..... Slag 3 ..... Lance

1b .... 노구4 ..... 장입슈트5 ..... 지금1b .... old man 4 ..... charging suit 5 ..... now

본 발명의 지금 부착 제거방법은 통상적인 전로 정련에서 용강을 출강하기 전에 용강 상부의 슬래그에 랜스를 통해 질소를 분사하여 비산된 슬래그를 전로의 노구 표면에 코팅함을 포함하여 구성된다.The present attachment removal method of the present invention comprises coating slag scattered by spraying nitrogen on the slag on top of the molten steel before tapping the molten steel in a conventional converter refining on the furnace sphere surface of the converter.

이하, 본 발명을 상세히 설명한다.Hereinafter, the present invention will be described in detail.

통상 일련의 전로 정련공정은 전로 내에 원료를 장입한 다음, 장입 원료에 랜스를 통하여 산소를 취련한 후, 취련에 의해 정련된 용강을 레이들에 출강하고나서 전로 내의 슬래그를 배제하는 조업을 진행된다. 이러한 전로 조업에서 정련이 완료된 후 약간의 슬래그를 전로 내에 남겨둔 상태에서 슬래그에 질소를 취입하여 전로의 내벽 표면을 슬래그로 코팅하는 통상적인 방법으로는 전로 노구까지 슬래그 코팅을 할 수 없다.In general, a series of converter refining processes are carried out to charge raw materials into a converter, and then to blow oxygen into the charged raw materials through a lance, and then to remove the slag in the converter after tapping the molten steel refined by the blow. . In this converter operation, after slag is left in the converter, the slag coating can not be applied to the converter furnace by the conventional method of injecting nitrogen into the slag and coating the inner wall surface of the converter with slag.

그러나, 본 발명에 의하면 상기 일련의 전로 정련과정에서 질소를 취입하여 전로의 노구에 슬래그 코팅이 가능하다. 본 발명은 전로 정련과정에서 취련된용강을 출강하기 앞서 사전에 슬래그를 전로의 노구에 코팅한다. 이에 따라, 노구에 부착된 지금을 자연 탈락시키도록 유도하는 것이다.However, according to the present invention, the slag coating is possible on the furnace furnace of the converter by blowing nitrogen during the series of converter refining processes. In the present invention, before slab molten steel blown during the converter refining process, the slag is coated on the furnace furnace of the converter in advance. Accordingly, the current attached to the furnace is induced to fall off naturally.

도3은 본 발명에 따라 전로의 노구에 부착된 지금을 간단히 제거할 수 있는 슬래그 코팅 과정을 보이고 있다. 도3과 같이, 본 발명은 전로(1)에서 취련을 완료한 후 용강(6)을 출강하기 전에 랜스(3)를 슬래그(2)의 상부에 위치시켜 랜스를 통해 질소를 취입한다. 질소를 취입하면 슬래그는 질소 분사각에 의해 반사각을 이루며 전로의 노구까지 비산되어 슬래그 코팅층(2a)이 노구에 고르게 형성된다.Figure 3 shows a slag coating process that can simply remove the now attached to the furnace mouth of the converter in accordance with the present invention. As shown in FIG. 3, the present invention blows nitrogen through the lance by placing the lance 3 on the slag 2 before the molten steel 6 is pulled out after completion of the blow in the converter 1. When nitrogen is blown in, the slag forms a reflection angle by the nitrogen injection angle and scatters to the furnace furnace port, so that the slag coating layer 2a is evenly formed on the furnace furnace.

본 발명에서 전로 노구 표면에 코팅되는 슬래그 코팅층의 두께는 약 10~ 30mm 정도로 하는 것이 바람직하다. 슬래그 코팅층의 두께가 너무 얇으면 부착된 지금이 자연적으로 탈락되지 않으며, 너무 두꺼우면 오히려 지금 제거 작업에 애로가 생길 수 있다.In the present invention, the thickness of the slag coating layer coated on the converter furnace sphere surface is preferably about 10 ~ 30mm. If the thickness of the slag coating layer is too thin, the adhered now does not fall off naturally, and if too thick, the removal work may be rather difficult.

슬래그 코팅층을 적절히 조절하기 위해서는 전로의 노구까지 슬래그가 비산되어 도달하기 위해서는 랜스의 높이를 전로의 연와 밑바닥을 기준으로 약 2,500~ 4,000mm 정도 이격시키는 것이 바람직하다. 전로 내의 슬래그 탕면을 수평으로 할 때, 랜스를 통해 질소를 취입하는 입사각과 반사각은 동일하므로 탕면과 약간 경사져 상기한 정도의 거리에서 질소가 취입되면 전로의 노구까지 매우 고르게 슬래그가 코팅될 수 있다. 이렇게 전로의 노구에 슬래그가 코팅되면, 노구에 지금이 붙더라도 전로를 경동시킬 때 지금이 자중에 의해 자연 탈락된다.In order to properly adjust the slag coating layer, it is preferable to space the lance about 2,500 to 4,000 mm based on the length and the bottom of the converter in order for the slag to be scattered to reach the furnace furnace of the converter. When the slag tap surface in the converter is leveled, the incident angle and the reflection angle of blowing the nitrogen through the lance are the same, so that when the nitrogen is blown at the above-mentioned distance, the slag may be coated evenly to the furnace's furnace. When slag is coated on the furnace's furnace, the current is naturally eliminated by the weight of the converter when it is attached to the furnace.

이하, 본 발명을 실시예를 통해 구체적으로 설명한다.Hereinafter, the present invention will be described in detail through examples.

[실시예]EXAMPLE

용강을 출강하기 전에 취련이 완료된 전로를 정립한 상태에서 랜스를 전로 연와 바닥으로부터 일정 높이 떨어진 곳에서 랜스를 정지시키고 질소를 13kg/㎠의압력으로 약 18,000N㎥/h 의 유량으로 슬래그의 상부에 3분 정도 취입하였다. 이때, 랜스는 노즐 경각이 약 7도인 3공 랜스를 사용하였다. 질소 취입을 완료한 후 전로 노구의 표면을 관찰하고, 슬래그 코팅층의 두께를 측정하여 표1에 나타내었다. 또한, 전로 내의 슬래그 성분은 표2와 같았다.Before the molten steel is pulled out, while the blower is established, the lance is stopped at a certain height away from the converter lead and bottom, and nitrogen is discharged to the upper part of the slag at a flow rate of about 18,000 N㎥ / h at a pressure of 13 kg / ㎠. It was blown for about 3 minutes. At this time, the lance used a three-hole lance having a nozzle angle of about 7 degrees. After completion of the nitrogen injection, the surface of the converter furnace ball was observed, and the thickness of the slag coating layer was measured and shown in Table 1. In addition, the slag component in a converter was as Table 2.

그 다음, 이러한 전로 노구 슬래그 코팅을 행한 전로를 이용하여 다음 동일한 방법으로 전로 정련을 행하고 취련시 전로 노구에 부착되는 지금 탈락 정도를 관찰하였다. 표1은 그 결과를 보이고 있다.Next, the converter was subjected to the converter furnace slag coating, and the converter was polished by the same method as described below. Table 1 shows the results.

구분division 전로 연와 바닥으로부터 랜스 높이(mm)Lance height (mm) from converter lead and bottom 슬래그 코팅층 두께(mm)Slag Coating Layer Thickness (mm) 지금 제거 상태Remove now 비교예1Comparative Example 1 2,0002,000 50mm 이상50mm or more 슬래그 코팅층 잔존Slag coating layer remaining 발명예1Inventive Example 1 2,5002,500 30mm30 mm 자연 탈락Natural elimination 발명예2Inventive Example 2 3,0003,000 20mm20 mm 자연 탈락Natural elimination 발명예3Inventive Example 3 3,5003,500 10mm10 mm 자연 탈락Natural elimination 발명예4Inventive Example 4 4,0004,000 10mm10 mm 자연 탈락Natural elimination 비교예2Comparative Example 2 4,5004,500 5mm 이하5mm or less 지금 잔존Remaining

성분ingredient T. FeT. Fe CaOCaO SiO2 SiO 2 MnOMnO Al2O3 Al 2 O 3 MgOMgO P2O5 P 2 O 5 조성(중량%)Composition (% by weight) 12.0~ 23.512.0 ~ 23.5 20.0~ 45.020.0 ~ 45.0 8.0~ 15.08.0 ~ 15.0 1.0~ 3.01.0 ~ 3.0 1.0~ 3.01.0 ~ 3.0 5.0~ 13.05.0 ~ 13.0 1.0~ 3.01.0 ~ 3.0

표1에 나타난 바와 같이, 전로 취련완료후 용강을 출강하기 전에 전로 연와 바닥으로부터 약 2,500~ 4,000mm 정도 떨어진 위치에서 랜스를 통해 질소를 취입한 발명예(1~4)의 경우 전로의 노구 상에 슬래그 코팅층이 적정한 두께로 고르게 형성되어 전로 출강을 행하기 위해 전로를 경동할 때 전로의 노구에 부착된 지금이 자연히 탈락하였다.As shown in Table 1, inventive examples (1-4) in which nitrogen was blown through the lance at a position about 2,500 to 4,000 mm from the edge and the bottom of the converter before tapping the molten steel after the converter was blown, The slag coating layer was evenly formed to an appropriate thickness, and now adhered to the furnace furnace of the converter when the converter is tilted to make the converter go out and fall naturally.

반면, 전로 노구 표면에 슬래그 코팅층이 너무 두껍거나 얇은 비교예(1)(2)의 경우 전로 노구에 부착된 지금의 제거가 용이하지 않았다.On the other hand, in the case of Comparative Example (1) (2), where the slag coating layer was too thick or too thin on the converter furnace surface, the current removal attached to the converter furnace bulb was not easy.

상술한 바와 같이, 본 발명에 의하면 전로 정련과정에서 용강을 출강하기 앞서 사전에 간단히 슬래그를 전로 노구 표면에 코팅시키므로써, 전로의 취련과정에서 노구 표면에 부착되는 지금을 간단히 제거할 수 있어 전로 조업이 안정될 뿐만 아니라 전로의 수명을 연장하는데도 일조할 수 있다.As described above, according to the present invention by simply coating the slag on the converter furnace surface in advance before tapping the molten steel in the converter refining process, it is possible to easily remove the now adhered to the furnace sphere surface during the blowing process of the converter. Not only is this stabilized, it can also help extend the life of the converter.

Claims (2)

전로 내에 원료를 장입한 다음, 장입 원료에 랜스를 통하여 산소를 취련한 후, 취련에 의해 정련된 용강을 출강하고나서 전로 내의 슬래그를 배제하는 일련의 전로 정련방법에 있어서,In a series of converter refining methods in which a raw material is charged into a converter, oxygen is blown to the charged raw material through a lance, and the molten steel refined by tapping is pulled out to remove slag in the converter. 상기 용강을 출강하기 전에 용강 상부의 슬래그에 랜스를 통해 질소를 분사하여 비산된 슬래그를 전로의 노구 표면에 10~ 30mm 두께로 코팅함을 특징으로 하는 질소를 이용한 전로 노구 부착지금의 제거방법.Before the molten steel before the molten steel by spraying nitrogen through the lance through the lance to the slag scattered slag coated on the furnace furnace surface of the converter, characterized in that for removing the furnace furnace furnace attachment using nitrogen. 제1항에 있어서, 상기 질소의 분사는 랜스를 전로 연와 바닥으로부터 2,500 내지 4,000mm 떨어진 위치에서 행함을 특징으로 하는 제거방법.The method of claim 1 wherein the injection of nitrogen is performed at a position 2,500 to 4,000 mm away from the converter lead and bottom.
KR1020010037040A 2001-06-27 2001-06-27 A Method for Removing Reclained lump steel on the Converter Throat Using Nitrogen Blowing KR100758435B1 (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100728829B1 (en) * 2005-04-12 2007-06-15 (주)다보컴 High brightness back light apparatus of vehicle
CN101575655B (en) * 2009-06-18 2010-12-08 攀钢集团攀枝花钢铁研究院有限公司 Method for lowering converter bottom

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JPS6156223A (en) * 1984-08-24 1986-03-20 Nippon Steel Corp Method for coating converter with slag
JPH11229021A (en) * 1998-02-13 1999-08-24 Nippon Steel Corp Method for protecting lining refractory in converter type furnace
US6627256B1 (en) * 1998-10-05 2003-09-30 Kawasaki Steel Corporation Method for slag coating of converter wall
KR100329341B1 (en) * 1999-10-25 2002-03-22 고학봉 Apparatus and method for coating interior of converter using nitrogen blowing

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100728829B1 (en) * 2005-04-12 2007-06-15 (주)다보컴 High brightness back light apparatus of vehicle
CN101575655B (en) * 2009-06-18 2010-12-08 攀钢集团攀枝花钢铁研究院有限公司 Method for lowering converter bottom

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