KR100832697B1 - Method for desiliconinzation of hot metal - Google Patents

Method for desiliconinzation of hot metal Download PDF

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KR100832697B1
KR100832697B1 KR1020010085464A KR20010085464A KR100832697B1 KR 100832697 B1 KR100832697 B1 KR 100832697B1 KR 1020010085464 A KR1020010085464 A KR 1020010085464A KR 20010085464 A KR20010085464 A KR 20010085464A KR 100832697 B1 KR100832697 B1 KR 100832697B1
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molten iron
sampling
sample
silicon
molten
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KR1020010085464A
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Korean (ko)
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KR20030055023A (en
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임동석
강병광
방준경
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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
    • C21C1/00—Refining of pig-iron; Cast iron
    • C21C1/04—Removing impurities other than carbon, phosphorus or sulfur
    • 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
    • F27D19/00—Arrangements of controlling devices
    • F27D2019/0003—Monitoring the temperature or a characteristic of the charge and using it as a controlling value

Abstract

본 발명은 용선 샘플링시 작업부하를 저감시키고, 샘플링 시간을 단축하여 탈규재 투입시기를 놓치는 것을 방지하도록 된 용선의 탈규방법을 제공하는 데 목적이 있다.An object of the present invention is to provide a method for desulfurization of molten iron which is designed to reduce the workload during molten iron sampling and to shorten the sampling time so as to prevent the missile injection time.

따라서, 본 발명은 고로에서 배출되는 용선의 출선속도를 측정하는 출선속도측정단계; 출선속도측정단계에서 측정된 용선의 출선속도에 따라 미리 세팅된 양의 탈규재를 용선에 투입하는 탈규재투입단계; 탈규재투입단계에서 탈규재가 투입되어 탈규된 용선을 샘플링하는 용선샘플링단계; 용선샘플링단계에서 샘플링된 샘플을 분석하는 샘플분석단계; 샘플분석단계에서 분석된 데이터에 의해 규소가 목표치보다 높을 경우에는 용선을 투입하고, 규소가 목표치보다 낮을 경우에는 탈규재를 재차 투입하는 2차탈규재투입단계를 포함하는 용선의 탈규방법을 제공한다.Therefore, the present invention is the discharge speed measurement step of measuring the discharge speed of the molten iron discharged from the blast furnace; A deaeration material input step of inputting a predetermined amount of deaeration material in the chartering line according to the drawing speed of the molten iron measured in the drawing speed measurement step; A molten metal sampling step of sampling the desulfurized molten iron by adding the desulfurizing material in the desulfurizing material input step; A sample analysis step of analyzing the sample sampled in the molten metal sampling step; According to the data analyzed in the sample analysis step, the molten iron is added if the silicon is higher than the target value, and if the silicon is lower than the target value, the molten iron is provided with a method of dissolving the molten iron including the second desulfurization material reinjecting step.

탈규, 샘플링, 용선Deregulation, Sampling, Melting

Description

용선의 탈규방법{METHOD FOR DESILICONINZATION OF HOT METAL}METHOD FOR DESILICONINZATION OF HOT METAL}

도 1은 본 발명에 따른 용선의 탈규방법 플로우챠트도.1 is a flow chart of the deregulation method of the molten iron according to the present invention.

도 2는 본 발명에 따른 용선의 탈규방법에 이용되는 용선샘플링장치를 개략적으로 나타내는 도면.Figure 2 schematically shows a molten iron sampling apparatus used in the method for deregulating molten iron according to the present invention.

<도면의 주요부분에 대한 부호의 설명><Description of the symbols for the main parts of the drawings>

10 : 용선샘플링장치 18 : 본체10: molten iron sampling device 18: main body

20 : 프로브 21 : 와이어20: probe 21: wire

22 : 가이드 24 : 주행레일22: guide 24: running rail

27 : 윈치 30 : 샘플분석장치27: winch 30: sample analysis device

본 발명은 고로에서 배출되는 용선을 탈규시키는 용선의 탈규방법에 관한 것으로서, 더욱 상세하게는 고로에서 배출되는 용선을 샘플링하고 샘플링 결과에 따라 탈규제 투입을 가감하므로 용선을 탈규시키는 용선의 탈규방법에 관한 것이다.The present invention relates to a deregulation method of a molten iron that deregulates the molten iron discharged from the blast furnace, and more particularly to a method of deregulating the molten iron to deregulate the molten iron because sampling and deregulation of the molten iron discharged from the blast furnace. It is about.

일반적으로 고로에서 배출되는 용선은 규소(Si) 함량이 높기 때문에 후공정인 전로에서 취련시 작업능률을 향상시키기 위하여 전로에 투입전 규소 함량을 낮 추는 것이 필요한다.In general, the molten iron discharged from the blast furnace has a high silicon (Si) content, it is necessary to lower the silicon content before entering the converter in order to improve the work efficiency when blowing in the converter is a post-process.

이러한 용선의 탈규방법은 작업자가 용선을 샘플링 한 후, 에어슈트를 통하여 샘플링된 샘플을 분석실로 보낸다.In this method of degreasing the molten iron, the operator samples the molten iron and then sends the sampled sample through the air chute to the analysis chamber.

이와 같이 분석실로 보내진 샘플은 분석실에서 분석되어 분석된 샘플의 규소 함량을 작업자가 볼 수 있도록 작업현장에 디스플레이 한다.The sample sent to the analysis room is analyzed in the analysis room and the silicon content of the analyzed sample is displayed on the work site for the operator to see.

따라서 작업자는 디스플레이된 규소의 함량에 따라 소정의 탈규제를 용선에 투입한다.Thus, the operator puts a certain deregulation into the molten iron according to the content of the displayed silicon.

그러나 이와 같이 샘플링은 작업자가 고온의 용선을 수작업으로 샘플링해야 하므로 이로 인해 작업부하가 증대되는 문제점이 있다.However, in this way, since the operator must manually sample the hot molten iron, there is a problem in that the workload is increased.

또한 샘플을 검사하는 시간이 과다하게 소요되어 적기에 샘플링의 결과를 알 수 없으므로 탈규재의 투입시기를 놓쳐 작업자가 통상의 양대로 탈규재를 용선에 투입하게 된다.In addition, it takes too much time to inspect the sample, so it is impossible to know the result of sampling in a timely manner.

따라서 탈규재의 양이 적으면 용선의 규소를 목표치만큼 제거할 수 없는 문제점이 있다.Therefore, if the amount of de-silicide is small, there is a problem that can not remove the silicon of the molten iron as a target value.

또한 탈규제의 양이 많으면 포밍이 일어나 용선이 끓어 넘치게 되므로 이로 인한 설비소손 등의 설비사고가 발생되는 문제점이 있다.In addition, if the amount of deregulation is large, the foaming occurs and the molten iron is boiled, resulting in equipment accidents such as equipment damage.

따라서 본 발명은 종래기술의 문제점을 해결하기 위하여 안출된 것으로, 그 목적은 용선 샘플링시 작업부하를 저감시키고, 샘플링 시간을 단축하여 탈규재 투입시기를 놓치는 것을 방지하도록 된 용선의 탈규방법을 제공하는 데 있다. Therefore, the present invention has been made to solve the problems of the prior art, the object of which is to provide a method for deregulating the molten iron to reduce the workload during the sampling of the molten iron, and to shorten the sampling time to prevent the missed injection timing. There is.

상기한 바와 같은 목적을 달성하기 위하여 본 발명은 고로에서 배출되는 용선을 탈규하는 용선의 탈규방법에 있어서, 고로에서 배출되는 용선의 출선속도를 측정하는 출선속도측정단계; 출선속도측정단계에서 측정된 용선의 출선속도에 따라 미리 세팅된 양의 탈규재를 용선에 투입하는 탈규재투입단계; 탈규재투입단계에서 탈규재가 투입되어 탈규된 용선을 샘플링하는 용선샘플링단계; 용선샘플링단계에서 샘플링된 샘플을 분석하는 샘플분석단계; 샘플분석단계에서 분석된 데이터에 의해 규소가 목표치보다 높을 경우에는 용선을 투입하고, 규소가 목표치보다 낮을 경우에는 탈규재를 재차 투입하는 2차탈규재투입단계를 포함하는 용선의 탈규방법을 제공한다.In order to achieve the object as described above, the present invention provides a method for deregulating molten iron discharged from the blast furnace, the discharge speed measuring step of measuring the discharge speed of the molten iron discharged from the blast furnace; A deaeration material input step of inputting a predetermined amount of deaeration material in the chartering line according to the drawing speed of the molten iron measured in the drawing speed measurement step; A molten metal sampling step of sampling the desulfurized molten iron by adding the desulfurizing material in the desulfurizing material input step; A sample analysis step of analyzing the sample sampled in the molten metal sampling step; According to the data analyzed in the sample analysis step, the molten iron is added if the silicon is higher than the target value, and if the silicon is lower than the target value, the molten iron is provided with a method of dissolving the molten iron including the second desulfurization material reinjecting step.

여기서 용선샘플링단계는 용선샘플링장치를 이용하여 용선을 샘플링하는 것이 바람직하다.In the molten iron sampling step, it is preferable to sample the molten iron using a molten iron sampling device.

또한 샘플분석단계는 샘플링된 샘플을 샘플링장에 샘플분석장치를 설치하여 분석하는 것이 바람직하다.In addition, in the sample analysis step, it is desirable to analyze the sampled sample by installing a sample analyzer in the sampling station.

이하 본 발명에 따른 바람직한 일실시예를 첨부된 도면을 참조하여 상세히 설명한다.Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

도 1은 본 발명에 따른 용선의 탈규방법 플로우챠트도이고, 도 2는 본 발명에 따른 용선의 탈규방법에 이용되는 용선샘플링장치를 개략적으로 나타내는 도면이다.1 is a flowchart illustrating a method for deregulating molten iron according to the present invention, and FIG. 2 is a view schematically illustrating a molten iron sampling apparatus used in the method for deregulating molten iron according to the present invention.

먼저 출선속도측정단계는 고로에서 배출되는 용선의 시간당 배출중량을 측정 하는 단계로서 대탕도의 하부에 설치된 중량검출기에 의해 용선의 배출량이 시간단위로 검출된다.First, the discharge speed measurement step is to measure the hourly discharge weight of the molten iron discharged from the blast furnace, and the discharge of the molten iron is detected in units of time by a weight detector installed in the lower part of the main bath.

다음으로 탈규재투입단계는 출선속도측정단계에서 측정된 용선의 출선속도에 따라 미리 세팅된 양의 탈규재를 용선에 투입하는 단계이다.Next, the deagulant input step is a step of injecting a predetermined amount of deagulant material into the chartering line according to the drawing speed of the molten iron measured in the drawing speed measurement step.

여기서 탈규재는 고로에서 배출되는 용선의 양에 통상적인 단위중량당 탈규재 투입량을 나누어 탈규재의 투입량을 결정한다.In this case, the degreasing material is determined by dividing the amount of degreasing material per unit weight by the amount of molten iron discharged from the blast furnace.

즉 통상적인 고로는 출선초기의 출선속도가 60t/h이고 출선함에 따라 속도가 336t/h까지 증대되고 이후 출선속도가 유지된다.That is, the conventional blast furnace, the starting speed of the starting point is 60t / h, the speed increases to 336t / h with the departure, and then the departure speed is maintained.

따라서 통상적인 탈규재의 투입량은 용선량의 1/60 이므로 출선초기의 투입량은 1t/h이고 출선함에 따라 투입량은 5.6t/h로 증대되고 이후 투입량이 유지된다.Therefore, since the input amount of the conventional degreasing material is 1/60 of the molten metal, the initial input amount is 1t / h, and the input amount is increased to 5.6t / h as it is discharged, and then the input amount is maintained.

여기서 탈규재는 생석회(CaO)로서 생석회 중의 O2-이온이 Si4+이온과 결합시켜 SiO2로 부상 분리시킨다.Here, the desulfurization material is quicklime (CaO), in which the O 2- ions in the quicklime bind with Si 4+ ions to float to SiO 2 .

이와 같이 세팅된 양에 따라 용선에 탈규재를 투입하게 되며, 투입된 탈규재는 용선속의 규소와 반응하여 슬래그로 용선의 상부로 부상분리된다.In this way, the degreasing material is added to the molten iron according to the set amount, and the injected degreasing material reacts with the silicon in the molten iron and is separated from the upper portion of the molten iron by slag.

다음으로 용선샘플링단계는 일차로 탈규된 용선을 샘플링하는 단계로서 용선샘플링장치를 이용하여 용선을 샘플링한다.Next, the molten iron sampling step samples the molten iron that is primarily deregulated and the molten iron is sampled using the molten iron sampling device.

여기서 용선샘플링장치(10)는 용선의 상단에 설치되는 주행레일(24)과, 주행레일(24)을 따라 이동하는 본체(18)와, 본체(18)의 이동을 제어하는 주행제어기(25)와, 본체(18)의 일측에 승하강이 가능하도록 설치된 가이드(22)와, 가이드(22)의 상부를 따라 이동하는 와이어(21)와, 와이어(21)를 권취하는 윈치(27)와, 와이어(21)의 선단에 설치되어 용강을 샘플링하는 프로브(20)로 이루어진다.Here, the molten iron sampling device 10 includes a traveling rail 24 installed at an upper end of the molten iron, a main body 18 moving along the traveling rail 24, and a traveling controller 25 controlling movement of the main body 18. And a guide 22 installed on one side of the main body 18 so as to move up and down, a wire 21 moving along the upper portion of the guide 22, a winch 27 winding the wire 21, It is composed of a probe 20 installed at the tip of the wire 21 to sample the molten steel.

이러한 용선샘플링장치(10)는 본체(18)가 주행제어기(25)의 제어에 의해서 주행레일(24)을 따라 이동하여 용선의 상부에 위치하게 되고, 용선의 상부에 위치한 본체(18)는 윈치(27)가 풀림으로 와이어(21)가 하강하여 와이어(21)의 선단에 위치한 프로브(20)가 용선에 침적된다.The molten iron sampling device 10 is the main body 18 is moved along the running rail 24 by the control of the travel controller 25 is located on the upper portion of the molten iron, the main body 18 located on the upper portion of the molten iron is a winch. As the 27 is released, the wire 21 descends, and the probe 20 located at the tip of the wire 21 is deposited on the molten iron.

또한 용선에 침적된 프로브(20)는 연납이 녹으면서 프로브(20)의 내부로 용선이 침투되어 용선의 샘플이 채취된다.In addition, the probe 20 deposited on the molten iron is a molten solder penetrates into the inside of the probe 20 while the solder is melted to sample the molten iron.

용선의 샘플이 채취되면 윈치(27)를 작동시켜 프로브(20)를 끌어 올림으로 용선을 샘플링한다.When the sample of the molten iron is collected, the winch 27 is operated to sample the molten iron by pulling up the probe 20.

다음으로 샘플분석단계는 용선샘플링단계에서 샘플링된 샘플을 분석하는 단계로 용선의 샘플이 배출되는 용선샘플링장치의 측면에 샘플분석장치를 설치하여 샘플을 샘플분석장치(30)에 투입하는 것이 바람직하다.Next, the sample analysis step is to analyze the sample sampled in the molten iron sampling step, it is preferable to install a sample analysis device on the side of the molten iron sampling device from which the sample of the molten iron is discharged, and to put the sample into the sample analyzing apparatus 30. .

위와 같이 샘플링장에 샘플분석장치(30)를 설치하므로 즉시 규소의 함량을 분석할 수 있다.Since the sample analysis device 30 is installed in the sampling station as described above, the content of silicon can be analyzed immediately.

한편 여기서 분석된 샘플의 분석 결과는 신호변환기를 통하여 디지털신호로 변환되어 제어패널에 전달된다.Meanwhile, the analysis result of the analyzed sample is converted into a digital signal through a signal converter and transmitted to the control panel.

다음으로 2차탈규재투입단계는 샘플분석단계에서 분석되어 제어패널에 전달 된 데이터에 의해 규소의 함량이 목표치보다 높을 경우 용선이 장입된 TLC(Topedo Ladle Car)를 이동시켜 대탕도로부터 용선을 투입시키고, 규소의 함량이 목표치보다 낮을 경우 용선에 탈규재를 투입한다. Next, the secondary de-silicide injection step is to analyze the sample analysis step, and when the content of silicon is higher than the target value by the data delivered to the control panel, the molten iron is introduced from the large bath by moving the TLC (Topedo Ladle Car) loaded with molten iron. In the case where the silicon content is lower than the target value, degreasing material is added to the molten iron.

이 때 탈규재의 투입은 벨트컨베이어의 구동모터를 제어하여 부족량이 공급되도록 하는 것이 바람직하다.At this time, it is preferable that the deregulating material is supplied so that the deficiency is supplied by controlling the driving motor of the belt conveyor.

이상 설명한 바와 같은 본 발명에 따른 용선의 탈규방법은 용선샘플링장치를 이용하여 용선을 샘플링하므로 작업부하가 크게 감소된다.As described above, in the method for deregulating molten iron according to the present invention, since the molten iron is sampled using the molten iron sampling device, the workload is greatly reduced.

또한 샘플링장에 샘플분석장치가 설치되여 샘플분석지연이 발생되지 않으므로 탈규재의 수동투입으로 인한 탈규량의 부족을 방지한다.In addition, since the sample analysis device is installed in the sampling station, there is no delay in analyzing the sample, thus preventing the shortage of de-quantity due to the manual injection of the desulfurization material.

아울러 탈규재 투입량이 과다하여 발생되는 용선의 끓음으로 인해 발생되는 설비사고를 미연에 방지하게 된다.In addition, it prevents equipment accidents caused by boiling of molten iron, which is caused by an excessive amount of degreasing material.

Claims (3)

고로에서 배출되는 용선을 탈규하는 용선의 탈규방법에 있어서,In the deregulation method of the molten iron which deregulates the molten iron discharged from the blast furnace, 상기 고로에서 배출되는 용선의 출선속도를 측정하는 출선속도측정단계;A discharge speed measurement step of measuring a discharge speed of the molten iron discharged from the blast furnace; 상기 출선속도측정단계에서 측정된 용선의 출선속도에 따라 미리 세팅된 양의 탈규재를 용선에 투입하는 1차 탈규재투입단계;A first desulfurizing material input step of inputting a predetermined amount of desulfurizing material into the molten iron according to the drawing speed of the molten iron measured in the drawing speed measurement step; 상기 탈규재투입단계에서 탈규재가 투입되어 탈규된 용선을 용선샘플링장치를 이용하여 샘플링하는 용선샘플링단계; A molten iron sampling step of sampling the desulfurized molten iron by adding the non-silicone material in the degreasing material input step using a molten iron sampling device; 상기 용선샘플링단계에서 샘플링된 샘플을 분석하는 샘플분석단계; 및A sample analysis step of analyzing a sample sampled in the molten iron sampling step; And 상기 샘플분석단계에서 분석된 데이터에 의해 규소가 목표치보다 높을 경우에는 용선을 투입하고, 규소가 목표치보다 낮을 경우에는 탈규재를 재차 투입하는 2차 탈규재투입단계를 포함하는 것을 특징으로 하는 용선의 탈규방법.When the silicon is higher than the target value according to the data analyzed in the sample analysis step, the molten iron is added, and if the silicon is lower than the target value, the second desulfurization material input step includes re-injecting the desulfurization material. How to Disregulate. 삭제delete 제 1 항에 있어서,The method of claim 1, 상기 샘플분석단계는 샘플링된 샘플을 샘플링장에 샘플분석장치를 설치하여 분석하는 것을 특징으로 하는 용선의 탈규방법In the sample analysis step, the deregulation method of the molten iron, characterized in that for analyzing the sampled sample by installing a sample analyzer in the sampling station
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JPH11209814A (en) * 1998-01-23 1999-08-03 Kawasaki Steel Corp Method for controlling charging quantity of desiliconizing agent in blast furnace

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11209814A (en) * 1998-01-23 1999-08-03 Kawasaki Steel Corp Method for controlling charging quantity of desiliconizing agent in blast furnace

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102020121139A1 (en) 2020-08-11 2022-02-17 Ford Global Technologies, Llc Method for operating a motor vehicle

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