KR20000075190A - A method charging ilmenite for protecting hearth fire brick of blast furnace - Google Patents

A method charging ilmenite for protecting hearth fire brick of blast furnace Download PDF

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KR20000075190A
KR20000075190A KR1019990019646A KR19990019646A KR20000075190A KR 20000075190 A KR20000075190 A KR 20000075190A KR 1019990019646 A KR1019990019646 A KR 1019990019646A KR 19990019646 A KR19990019646 A KR 19990019646A KR 20000075190 A KR20000075190 A KR 20000075190A
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South Korea
Prior art keywords
charging
blast furnace
side wall
ore
ilmenite
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KR1019990019646A
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Korean (ko)
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이상호
김재식
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이구택
포항종합제철 주식회사
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Priority to KR1019990019646A priority Critical patent/KR20000075190A/en
Publication of KR20000075190A publication Critical patent/KR20000075190A/en

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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B5/00—Making pig-iron in the blast furnace
    • C21B5/008—Composition or distribution of the charge
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21B—MANUFACTURE OF IRON OR STEEL
    • C21B7/00—Blast furnaces
    • C21B7/04—Blast furnaces with special refractories
    • C21B7/06—Linings for furnaces

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacture Of Iron (AREA)

Abstract

PURPOSE: A method for charging ilmenite for protection of a furnace bottom side wall is provided to prevent a lower brick erosion of iron notch of a blast furnace and a temperature rising by charging a specific amount of ilmenite only in a temperature rising part of the furnace bottom side wall. CONSTITUTION: A method for charging ilmenite for protection of a furnace bottom side wall includes the steps of charging ilmenite(3-1) of 3 to 30kg/T-P in a temperature rising part of a furnace bottom side wall of a blast furnace(1), which is set as a local charging areas, in notch areas of 1 to 5 within the range of rotation of 1 to 4 one to every charges of 3 to 10 before charging materials are charged at a tilting angle per each notch when a sounding arrives at a charge reference line(3-2), and charging from third to thirty times.

Description

로저측벽 보호를 위한 티탄광석 장입방법{A METHOD CHARGING ILMENITE FOR PROTECTING HEARTH FIRE BRICK OF BLAST FURNACE}A METHOD CHARGING ILMENITE FOR PROTECTING HEARTH FIRE BRICK OF BLAST FURNACE}

본 발명은 로저측벽 보호를 위한 티탄(TiO2)광석 장입방법에 관한 것으로, 특히 로저측벽의 온도상승부위에만 일정량의 티탄광석을 장입하도록 제어함으로써 고로의 출선구 하부연와침식 및 온도상승을 방지할 수 있는 로저측벽 보호를 위한 티탄(TiO2)광석 장입방법에 관한 것이다.The present invention relates to a titanium (TiO 2 ) ore charging method for the protection of the bottom side of the furnace, in particular to control the loading of a certain amount of titanium ore only in the temperature rise of the bottom side of the blast furnace to prevent the bottom edge and erosion and the rise The present invention relates to a titanium (TiO 2 ) ore charging method for protecting the lower side wall.

일반적으로, 고로조업은 도1에 도시한 바와같이 원료빈(6-4,6-5)에서 절출된 광석과 소결광이 벨트콘베어(6)에 의해 로정으로 공급되어 플랩게이트(2-4)와 실링변(2-3)을 거쳐 로정호퍼(2)에 저장된다.In general, in the blast furnace operation, as shown in FIG. 1, ore and sintered ore cut out from the raw material bins 6-4 and 6-5 are supplied to the furnace by the belt conveyor 6 to supply the flap gate 2-4 with the flap gate 2-4. It is stored in the row hopper 2 via the sealing edge 2-3.

그리고, 로정호퍼(2)에 장입된 장입물은 선회슈트(2-2)를 통해 설정된 각 노치별 경동각도로 제어되어 코크스(입도 35∼55mm), 대립소결광(입도 12∼50mm), 소립소결광(입도 5∼12mm)의 순서로 장입된다.In addition, the charges loaded into the row hopper (2) is controlled at a tilt angle for each notch set through the turning chute (2-2) to coke (grain size 35 to 55 mm), allelic sintered light (particle size 12 to 50 mm), small sintered light It is charged in the order of (particle size 5-12 mm).

이때, 코크스는 반경방향으로 균일하게 장입되어 고로(1)의 상부에서 안정된 가스흐름으로 통기성 및 가스이용을 극대화하고, 이로부터 고로의 중심부온도가 높고 중간부 및 로벽부의 가스흐름이 균일하게 유지되는 연화융착대(1-1)를 형성하게 된다.At this time, the coke is charged uniformly in the radial direction to maximize the breathability and gas utilization with a stable gas flow at the top of the blast furnace (1), from which the central temperature of the blast furnace is high and the gas flow in the middle and the furnace wall is kept uniform The soft fusion zone 1-1 is formed.

또한, 로벽측에는 환원성 및 통기성이 우수한 소립소결광을 장입시켜 로벽부의 불활성대 생성을 방지하고, 고로(1)의 상부에 장입물층이 형성되면서 로벽보호를 유도하게 된다.In addition, by inserting small sintered ore with excellent reducing and breathability on the furnace wall side to prevent the generation of inert zone of the furnace wall portion, while the charge layer is formed on the top of the blast furnace 1 to induce the furnace wall protection.

한편, 풍구(1-2)를 통해 고로(1)내로 유입되는 열풍에 의해 장입물이 환원 및 용융되면서 용융물(용선과 슬래그)(1-3)을 생산하게 되고, 출선구를 통해 대탕도로 출선된다.On the other hand, as the charge is reduced and melted by the hot air flowing into the blast furnace 1 through the tuyere (1-2) to produce the melt (molten iron and slag) (1-3), and go out to Daetangdo through the exit port do.

이때, 고로(1) 내부의 용융물(1-3)은 극심한 유동현상 및 화학반응에 의해 출선구의 하부 연와를 침식 및 마모시키게 되고, 연와의 침식 가속화로 연와내에 가스통로가 형성되면서 연와의 탈락현상이 진행되면 출선구의 하부측벽온도가 급상승된다.At this time, the melt 1-3 in the blast furnace 1 is eroded and worn down the lower edge of the exit port by the extreme flow phenomenon and chemical reactions, the gas passage is formed in the duct due to the erosion of the erosion and falling off the duct As the phenomenon progresses, the lower side wall temperature of the exit port increases rapidly.

이러한, 종래의 문제점을 개선하기 위하여 고로(1)의 풍구(1-2)에 열풍제어변을 설치하여 출선구의 상부로 공급되는 열풍량을 줄임으로써 그 주위에서의 용융물(1-3) 발생량을 줄이는 방법을 사용하였으나, 로황이 불안정해지면서 이웃하는 풍구에 부하를 가중시킴으로써 풍구의 파손 등 대형사고를 유발시키게 된다.In order to improve such a conventional problem, by installing a hot air control valve in the blast furnace (1-2) of the blast furnace (1) to reduce the amount of hot air supplied to the upper portion of the exit port, the amount of melt (1-3) generated in the surroundings However, as the furnace sulfur becomes unstable, the load on neighboring windballs is increased, causing large accidents such as breakage of windballs.

또한, 출선구를 폐쇄하고 출선구의 내부보호벽을 형성하는 머드재의 충전량을 증가시키거나, 머드재에 산화티타늄을 일정비율로 혼합하여 출선구에 충전하는 방법으로 용융물(1-3)에 의한 출선구의 하부연와의 침식 및 마모를 방지하였으나, 충전되는 머드재는 그 비중에 있어 용융물보다 가볍기 때문에 그 재질상 출선구의 내벽에 충분한 접착이 되지않아 출선구의 하부온도저하 및 연와침식방지를 위한 근본적인 해결책이 되지 못하였다.In addition, the amount of filling of the mud material forming the inner protective wall of the exit port is increased, or the mud material is mixed with titanium oxide at a predetermined ratio to fill the exit port. Erosion and abrasion with the lower edge of the piling was prevented, but since the mud material filled is lighter than the melt in its specific gravity, the material is not sufficiently adhered to the inner wall of the tapping outlet so that the bottom temperature of the tap is lowered and the erosion prevention There was no solution.

그리고, 고로장입물에 TiO2광석을 혼합하여 장입시켜 고로하부의 용융물의 점성을 증대시키고, 로저측벽연와에 대한 용융물이 미치는 부하를 줄여서 로저측벽온도를 제어하는 방법의 경우 값비싼 TiO2광석이 고로내부의 전방향에 걸쳐 장입됨으로써 비경제적이고, 로저측벽의 온도상승부위외 용융물의 점성을 증대시켜 흐름을 방해하게 되면서 로황을 악화시키는 동시에 용융물의 배출불량을 유발시키게 된다.In addition, the TiO 2 ore is mixed and charged into the blast furnace charge to increase the viscosity of the melt at the bottom of the blast furnace, and in the case of controlling the furnace side wall temperature by reducing the load exerted by the melt on the furnace side wall edge, the expensive TiO 2 ore is Charging through the blast furnace in all directions is uneconomical, increasing the viscosity of the melt outside the rise of the temperature of the bottom side wall, impeding the flow while deteriorating the furnace sulfur and causing the discharge of the melt.

본 발명은 로저측벽의 온도상승부위에만 일정량의 티탄광석을 장입하도록 제어함으로써 고로의 출선구 하부연와침식 및 온도상승을 방지할 수 있는 로저측벽 보호를 위한 티탄(TiO2)광석 장입방법을 제공함에 그 목적이 있다.The present invention provides a method of loading titanium (TiO 2 ) ore for protecting the side wall of the furnace that can prevent the lower edge edge erosion and erosion and the temperature rise of the blast furnace by controlling to load a certain amount of titanium ore only to the temperature rise of the bottom side wall. The purpose is.

도1은 고로의 장입물 장입공정을 나타내는 공정도,1 is a process chart showing the charging process of the blast furnace;

도2는 본 발명에 따른 로저측벽 보호를 위한 티탄광석 장입방법을 나타내는 모식도,Figure 2 is a schematic diagram showing a titanium ore charging method for protecting the Roger side wall according to the present invention,

도3은 본 발명에 따른 로저측벽 보호를 위한 티탄광석 장입방법에 의해 장입된 고로반경방향의 장입물 분포형상을 나타내는 모식도,Figure 3 is a schematic diagram showing the shape of the distribution of the charge in the blast furnace radial direction charged by the titanium ore charging method for the protection of the lower side wall according to the present invention,

도4는 본 발명에 따른 로저측벽 보호를 위한 티탄광석 장입방법에 의한 장입구간을 나타내는 평면도이다.Figure 4 is a plan view showing a charging section by the titanium ore charging method for protecting the lower side wall according to the present invention.

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

1: 고로 1-1: 연화융착대 1-2: 풍구 1-3: 용융물 1-5: 괴상대 1-6: 사운딩 2: 로정호퍼 2-1: 광량조절변 2-2: 장입선회슈트 2-3: 실링밸브 2-4: 이동슈트 3-1: 티탄광석장입부위 3-2: 장입기준선 3-3: 출선구 5-1: 로저부의 티탄베어 5-2: 로저연와 5-3: 로심코크스층 6: 벨트콘베어 6-1: 코크스저장호퍼 6-2: 대립소결광저장호퍼 6-3: 소립소결광저장호퍼 6-4: 코크스저장조 6-5: 광석저장조 7-1: 코크스 7-2: 중괴코크스 8-1: 코크스층 8-2: 대립광석층 8-3: 소립광석층 8-4: 국부장입된 티탄광석층 10,11,12,13: 티탄광석의 국부장입구간 14: 로저부용선 15: 로저부슬래그DESCRIPTION OF SYMBOLS 1: Blast furnace 1-1: Softening fusion | melting zone 1-2: Fenggu 1-3: Melt 1-5: Mass 1-6: Sounding 2: Rojeong hopper 2-1: Light control valve 2-2: Charge turning chute 2-3: Sealing valve 2-4: Transfer chute 3-1: Titanium ore loading part 3-2: Charging baseline 3-3: Outlet 5-1: Titanium bearing 5-2 of Roger part 5-2: Roger lead and 5-3: Low core coke layer 6: Belt conveyor 6-1: Coke storage hopper 6-2: Opposite sintered ore storage hopper 6-3: Small sintered ore storage hopper 6-4: Coke storage tank 6-5: Ore storage 7-1: Coke 7-2 : Coke layer 8-1: Coke layer 8-2: Opposition ore layer 8-3: Small particle ore layer 8-4: Locally loaded titanium ore layer 10, 11, 12, 13: Local loading section of titanium ore 14: Roger Buoy Ship 15: Roger Slag

상기한 목적을 달성하기 위하여 본 발명은 사운딩이 장입기준선에 도달하면 각 노치별 경동각도로 장입물을 장입하기 전에 국부장입구간으로 설정되는 고로의 로저측벽온도상승부위에 3∼30㎏/T-P의 TiO2광석을 1∼5노치구간에서 1∼4회전의 범위로 3∼10 차지마다 1회씩 장입하여 총 3∼30회에 걸쳐 장입하는 것을 특징으로 하는 로저측벽 보호를 위한 티탄광석 장입방법을 제공한다.In order to achieve the above object, the present invention is 3 ~ 30kg / TP in the furnace side wall temperature rise of the blast furnace which is set to the local charging section before the charge at the angle of tilt angle for each notch when the sounding reaches the charging baseline TiO 2 ore is charged once every 3 to 10 charges in a range of 1 to 4 turns in a 1 to 5 notch section, and a total of 3 to 30 times are charged. to provide.

도면을 참조하여 본 발명을 설명한다.The present invention will be described with reference to the drawings.

도2는 본 발명에 따른 로저측벽 보호를 위한 티탄광석 장입방법을 나타내는 모식도이고, 도3은 본 발명에 따른 로저측벽 보호를 위한 티탄광석 장입방법에 의해 장입된 고로반경방향의 장입물 분포형상을 나타내는 모식도이며, 도4는 본 발명에 따른 로저측벽 보호를 위한 티탄광석 장입방법에 의한 장입구간을 나타내는 평면도이다.Figure 2 is a schematic diagram showing a titanium ore charging method for protecting the Roger side wall according to the present invention, Figure 3 is a load distribution shape of the blast furnace radial direction charged by the titanium ore charging method for the Roger side wall protection according to the present invention. 4 is a plan view showing a charging section by a titanium ore charging method for protecting the Roger side wall according to the present invention.

일반적으로, 고로조업은 장입물의 높이가 장입기준선(3-2)에 이르면 로정호퍼(2)에 저장되어 있는 코크스와 소결광이 선회슈트(2-2)를 통해 교대로 장입되어 층상을 이루면서 장입된다.In general, when the height of the charge reaches the charging reference line (3-2), the coke and the sintered ore stored in the row hopper (2) are charged through the turning chute (2-2) to form a layered charge. .

이때, 본 발명에서는 장입물의 장입완료 후, 사운딩(Sounding)(1-6)에 의해 장입물의 레벨관리범위가 감지되면 장입물의 장입개시 전, 장입물의 설정된 각 노치별(Notch ; 로벽부터 로중심까지의 반경을 11단계로 분할) 경동각도에 도달하면 로저측벽의 온도상승부위에 TiO2광석(3-1)의 장입을 선택하게 된다.At this time, in the present invention, if the level management range of the charge is detected by the sounding (1-6) after the completion of the charge of the charge, before the start of the charge of the charge, each set notch of the charge (Notch; furnace center from the furnace wall After dividing the radius into 11 steps), when the tilt angle is reached, the TiO 2 ore (3-1) is selected for the temperature rise of the lower side wall.

여기서, 장입각도가 설정이 되면 정상조업 O/C수준의 TiO2광석(3-1)을 선회슈트(2-2)를 통해 로저측벽의 온도상승부위에 3∼30㎏/T-P를 장입하게 되는데, 이때 3∼10 charge마다 1회씩 장입하여 총 3∼30회에 걸쳐 장입하게 되고, 로저측벽의 온도저하추세를 보고 추가 장입여부를 결정하게 된다.In this case, when the charging angle is set, 3 ~ 30㎏ / TP is charged into the temperature rising part of the lower side wall of the TiO 2 ore (3-1) of the normal operation O / C level through the turning chute (2-2). In this case, charging is performed once every 3 to 10 charges, and charging is performed for a total of 3 to 30 times. The temperature drop trend of the lower side wall determines the additional charging.

그리고, TiO2광석(3-1)의 장입방향설정은 총4등분하여 4개의 장입구간(10,11,12,13)으로 구분하고, 장입모드는 장입량에 따라 1∼5노치범위로 각각 총1∼4회의 범위로 실시하게 된다.The TiO 2 ore 3-1 is divided into four equally divided into four charging sections 10, 11, 12, and 13, and the charging mode is set in the range of 1 to 5 notches depending on the loading amount. It is performed in the range of 1 to 4 times.

한편, 정상조업 O/C수준의 TiO2광석(3-1)을 3∼30㎏/T-P범위로 장입하는 이유는 2㎏/T-P이하일 경우 그 장입부분의 로저부의 용선흐름을 억제하기 위한 효과가 나타나지 않게 되고, 31㎏/T-P 이상시 과다한 TiO2광석(3-1)의 장입으로 용융물의 배출불량 및 로황악화의 우려가 있다.The reason for loading TiO 2 ore (3-1) in the normal operation O / C level in the range of 3 to 30 kg / TP is less than 2 kg / TP. There is a risk of poor discharge of the melt and deterioration of the melt due to excessive loading of TiO 2 ore (3-1) at 31 kg / TP or more.

그리고, TiO2광석(3-1)을 3∼10charge마다 1회씩 장입하는 이유는 1∼2charge마다 1회씩 장입할 경우 순간적인 로저온도의 측벽부에 과다한 TiO2광석(3-1)의 장입으로 용선(14)의 유동성 악화와 통액성 불량을 초래하게 되고, 11charge이상마다 1회씩 장입할 경우 공급되는 TiO2광석에 의한 용선의 유동성 억제와 로저부의 티탄베어(5-1)를 형성하기 어렵다.Then, the contents of TiO 2 ore (3-1) once the excess TiO 2 in the ore charged reason that at the moment of the side wall portion of Roger temperature if charged once per every 1~2charge 3~10charge 3-1 The molten iron 14 is deteriorated in fluidity and poor liquidity, and when charged once every 11 charges or more, it is difficult to suppress the flow of molten iron by the TiO 2 ore supplied and to form the titanium bearing 5-1 of the lower portion.

또한, TiO2광석(3-1)의 장입모드에 있어서, 1∼5노치범위로 장입하는 이유는 가능한한 TiO2광석을 로벽부와 중간부위에 집중적으로 장입함으로써 티탄베어(5-1)의 형성효과를 안정적으로 확보하기 위함이다.In addition, in the charging mode of the TiO 2 ore 3-1, the reason for charging in the range of 1 to 5 notches is that as much as possible, TiO 2 ore is concentrated in the furnace wall portion and the intermediate portion of the titanium bearing 5-1. This is to secure the formation effect stably.

더욱이, TiO2광석(3-1)의 장입모드에 있어서, 1∼5노치범위에서 1∼4회전의 범위로 장입하는 이유는 5회전이상이 되면 장입량이 과다하여 로황악황의 원인을 제공하게 된다.Furthermore, in the charging mode of the TiO 2 ore 3-1, the reason for charging in the range of 1 to 4 turns in the range of 1 to 5 notches is that the amount of charge is excessive when 5 turns or more, thereby providing the cause of furnace sulfur. .

본 발명은 로저측벽의 온도상승부위에만 적은 양의 티탄광석을 장입하도록 제어함으로써 고로의 출선구 하부연와침식 및 온도상승을 방지할 수 있고, 이로부터 안정적인 로황확보로 생산성을 향상시킬 수 있을 뿐만아니라 고로의 수명을 연장할 수 있는 효과를 제공하게 된다.The present invention can be controlled to charge a small amount of titanium ore only in the temperature rise portion of the lower side wall of the blast furnace to prevent the lower edge and erosion and temperature rise of the blast furnace opening, thereby to improve the productivity by securing a stable furnace from this. It will provide the effect of extending the life of the blast furnace.

Claims (1)

사운딩(1-6)이 장입기준선(3-2)에 도달하면 각 노치별 경동각도로 장입물을 장입하기 전에 국부장입구간(10,11,12,13)으로 설정되는 고로(1)의 로저측벽온도상승부위에 3∼30㎏/T-P의 TiO2광석(3-1)을 1∼5노치구간에서 1∼4회전의 범위로 3∼10 차지마다 1회씩 장입하여 총 3∼30회에 걸쳐 장입하는 것을 특징으로 하는 로저측벽 보호를 위한 티탄광석 장입방법.When the sounding (1-6) reaches the charging baseline (3-2) of the blast furnace (1) which is set to the local charging section (10, 11, 12, 13) before charging the load at the tilt angle for each notch 3 to 30 kg / TP TiO 2 ore (3-1) was charged once every 3 to 10 charges in the range of 1 to 4 turns in the 1 to 5 notch section at the bottom wall temperature rise area. A titanium ore charging method for protecting the lower side wall, characterized in that the charge over.
KR1019990019646A 1999-05-29 1999-05-29 A method charging ilmenite for protecting hearth fire brick of blast furnace KR20000075190A (en)

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