KR100370574B1 - A method for dephosphorizing using desulphurization dust - Google Patents
A method for dephosphorizing using desulphurization dust Download PDFInfo
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- KR100370574B1 KR100370574B1 KR10-1998-0030918A KR19980030918A KR100370574B1 KR 100370574 B1 KR100370574 B1 KR 100370574B1 KR 19980030918 A KR19980030918 A KR 19980030918A KR 100370574 B1 KR100370574 B1 KR 100370574B1
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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
- C21C1/02—Dephosphorising or desulfurising
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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
- C21C1/02—Dephosphorising or desulfurising
- C21C1/025—Agents used for dephosphorising or desulfurising
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- 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
- F27D3/0025—Charging or loading melting furnaces with material in the solid state
- F27D3/0026—Introducing additives into the melt
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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
- C21C2200/00—Recycling of waste material
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- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
Abstract
본 발명은 제철소 예비처리공정중 실시하는 용선의 탈린처리방법에 관한 것으로서, 보다 상세하게는 용선중의 인(P)을 산화칼슘(CaO)을 투입하여 제거하는 방법에 있어서, 상기 용선중으로 전체 산화칼슘(CaO) 투입량의 70~75중량%가 되도록 분CaO를 투입원단위로 34∼37kg/T.P. 투입하고, 소결반광을 투입원단위로 28∼40kg/T.P. 투입하면서, 용선중으로 전체 산화칼슘(CaO) 투입량의 25∼30중량%가 되도록 CaO성분이 함유된 탈황더스트를 용선중으로 투입하는 것을 특징으로 하는 탈황더스트를 이용한 용선의 탈린방법에 관한 것이다.The present invention relates to a method for removing molten iron from molten iron during the pretreatment process in steel mills, and more particularly, in the method for removing phosphorus (P) in molten iron by adding calcium oxide (CaO), total oxidation in the molten iron. 34 ~ 37kg / TP of powdered CaO as input unit to make 70 ~ 75% by weight of calcium (CaO) input amount 28-40 kg / T.P. The present invention relates to a method for demolition of molten iron using desulfurized dust, wherein the desulfurized dust containing CaO component is introduced into the molten iron so as to be 25 to 30% by weight of the total amount of calcium oxide (CaO) in the molten iron.
상기와 같은 본 발명에 의해 폐기되던 탈황더스트를 재활용하게 됨으로써 종래 사용되던 탈린제의 투입원단위를 저감할 수 있음은 물론 인과 직접적으로 반응하는 FeO 성분을 분체상태로 투입함으로써 탈린효율을 보다 향상시킬 수 있다.By recycling the desulfurized dust discarded by the present invention as described above, it is possible to reduce the input unit of the dephosphorization agent conventionally used, as well as to improve the dephosphorization efficiency by injecting the FeO component directly reacting with phosphorus in powder state. have.
Description
본 발명은 제철소 예비처리 공정중 실시하는 용선의 탈린처리방법에 관한 것으로서 보다 상세하게는 용선의 탈황처리시 발생하는 탈황더스트를 이용하여 용선중의 인을 효율적으로 제거함으로써 용선의 단위 톤당 사용되던 조성물의 원단위를 저감시킬 수 있는 탈황더스트를 이용한 용선의 탈린방법에 관한 것이다.The present invention relates to a method for desalination of molten iron which is carried out during the pretreatment process of steel mills, and more particularly, a composition used per unit ton of molten iron by efficiently removing phosphorus from molten iron by using desulfurization dust generated during desulfurization of molten iron. The present invention relates to a method of desalination of molten iron using desulfurization dust that can reduce the raw unit of.
일반적인 용선의 탈린처리방법을 살펴보면 먼저, 고로에서 출탕된 용선을 오엘시(OLC, Open Ladle Car)에 담은 후 예비처리장으로 이송시킨다.Looking at the method of delineation of general molten iron, first, the molten iron from the blast furnace is contained in OEL (OLC, Open Ladle Car) and then transferred to the pretreatment plant.
이어서 상기 OLC내의 용선에 침적시킨 랜스를 통하여 분 CaO를 취입하며, 동시에 소결반광과 형성을 OLC 상부로부터 용선에 투입하여 탈린처리를 실시하고 있으며, 상기의 탈린처리 완료 이후 탈황처리를 실시하고 있다.Subsequently, powdered CaO is blown through the lance deposited in the molten iron in the OLC, and at the same time, sintered reflection and formation are introduced into the molten iron from the upper portion of the OLC, and dephosphorization treatment is performed.
한편, 상기의 탈린제 투입량은 100톤 용선을 기준으로 분 CaO를 20∼25kg/T.P.(Ton Pig iron) 소결반광을 탈린전 인(P)의 함유량에 따라 35∼50kg/T.P. 그리고 형석을 2∼4kg/T.P. 이며, 그 처리시간은 20분 내외로 하고 있다.On the other hand, the input amount of the dephosphorizing agent is based on 100 ton molten iron, 20 to 25kg / T.P. (Ton Pig iron) sintered semi-reflective 35 ~ 50kg / T.P. And fluorspar 2-4kg / T.P. The processing time is about 20 minutes.
여기서, 상기의 탈린제에 의한 용선중의 탈린과정을 살펴보면 용선중의 인성분은 용선의 상부에서 투입되는 소결반광과 다음과 같은 반응을 하여 슬래그중으로 제거된다.Here, looking at the process of delineation in the molten iron by the dephosphorization agent, the phosphorus component in the molten iron is removed into the slag by the following reaction with the sintered semireflection introduced from the upper portion of the molten iron.
2[P] + 5FeO = (P2O5) + 5Fe ………… (1)2 [P] + 5FeO = (P 2 O 5 ) + 5Fe... … … … (One)
여기서, ( ) 안의 성분은 슬래그, [ ] 안의 성분은 용선중의 성분을 각각 나타낸다.Here, the components in () denote slag, and the components in [] denote components in the molten iron, respectively.
이와 같이 소결반광과 반응하여 발생된 P2O5는 분 CaO와 다음과 같은 반응을 통해 안정한 화합물로 형성된다.P 2 O 5 generated by the reaction with the sintered reflection is formed as a stable compound through the reaction with the powder CaO.
(P2O5) + 3(CaO) →(3CaO P2O5)(P 2 O 5 ) + 3 (CaO) → (3CaO P 2 O 5 )
또는 (P2O5) + 4(CaO) →(4CaO P2O5) ................... (2)Or (P 2 O 5 ) + 4 (CaO) → (4CaO P 2 O 5 ) ......... (2)
여기서 주반응을 일으키는 원소는 소결반광의 FeO 성분이며, 분체로 취입되는 CaO는 탈린된 인산화물이 다시 용선중으로 이동하지 못하도록 슬래그중의 인산화물을 안정화시키는 역할을 한다.Here, the element causing the main reaction is the FeO component of the sintered semi-reflective light, CaO blown into the powder serves to stabilize the phosphate in the slag so that dephosphorized phosphate does not move back to the molten iron.
한편, 분 CaO의 입도는 랜스의 막힘을 방지하고, 취입성을 좋게 하기 위하여 통상 0.1mm 이하의 미분을 사용하고 있다.On the other hand, in order to prevent clogging of lance and to improve blownability, the particle size of powder CaO normally uses fine powder of 0.1 mm or less.
또한, 탈린반응이 진행하여 용선중 인이 슬래그중으로 이동하여도 슬래그의 유동성 자체가 분 CaO의 투입으로 인해 떨어지므로 유동성의 확보를 위해 형석을 투입하고 있다.In addition, even though phosphorus in molten iron moves to the slag due to the delineation reaction, the flowability of the slag falls due to the input of the powdered CaO, thus fluorite is added to secure the fluidity.
그러나, 상기와 같은 종래의 기술에서 탈린반응의 주요원소인 소결반광이 용선중의 인과 적극적으로 반응하여야 하나, 용선상부에서 투입되므로 인해 용선상부에서만 용선과 반응을 할 뿐, 용선중에 있는 인과는 반응할 수 있는 여력을 충분히 갖지 못하며 이에 따라 탈린후 목표 인성분을 맞추기 위해 소결광이 과도하게 투입되고 있는 문제점이 있었다.However, in the prior art as described above, the sintered semireflection, which is the main element of the Tallinn reaction, needs to actively react with the phosphorus in the molten iron, but only reacts with the molten iron in the molten iron because it is injected from the molten iron. There is not enough room to do so, there was a problem that the sintered ore is excessively input to meet the target phosphorus component after the Tallinn.
본 발명은 상기와 같은 문제점을 해결하기 위해 안출된 것으로서 제강공정의 용선 예비처리공정 중 탈황처리를 실시할 때 발생하는 탈황더스트를 이용하여 탈린처리를 행함으로써 탈린효율의 증대뿐만 아니라 과도하게 투입되는 소결반광 및 분 CaO의 원단위를 저감시킬 수 있는 탈황더스트를 이용한 용선의 탈린방법을 제공하는 것을 그 목적으로 한다.The present invention has been made in order to solve the above problems, and the dephosphorization treatment is performed using desulfurization dust generated when desulfurization treatment is performed during the molten iron preliminary treatment of the steelmaking process, thereby increasing the dephosphorization efficiency as well as being excessively added. It is an object of the present invention to provide a method for demolition of molten iron using desulfurization dust capable of reducing the raw unit of sintered semi-reflective light and powdery CaO.
도 1은 종래의 탈린방법의 의한 용선중의 Si, Mn, P, S 성분 변화를 나타내는 그래프도,1 is a graph showing changes in Si, Mn, P, and S components in molten iron by a conventional Tallinn method;
도 2는 본 발명의 탈린방법에 의한 용선중의 Si, Mn, P, S 성분의 변화를 나타내는 그래프도,2 is a graph showing changes in Si, Mn, P, and S components in molten iron by the Tallinn method of the present invention;
도 3은 시간에 따른 용선중의 인 성분 거동을 초기 인성분으로 나누어서 백분율로 나타낸 그래프도이다.Figure 3 is a graph showing the percentage of phosphorus component behavior in the molten iron over time divided by the initial phosphorus component.
상기와 같은 목적을 달성하기 위하여, 본 발명은 용선중의 인(P)을 산화칼슘(CaO)을 투입하여 제거하는 방법에 있어서, 상기 용선중으로 전체 산화칼슘(CaO) 투입량의 70∼75중량%가 되도록 분CaO를 투입원단위로 34~37kg/T.P. 투입하고, 소결반광을 투입원단위로 28~40kg/T.P. 투입하면서, 용선중으로 전체 산화칼슘(CaO) 투입량의 25∼30중량%가 되도록 CaO성분이 함유된 탈황더스트를 용선중으로 투입하는 것을 특징으로 하는 탈황더스트를 이용한 용선의 탈린방법을 제공한다.In order to achieve the above object, the present invention provides a method for removing phosphorus (P) in the molten iron by adding calcium oxide (CaO), 70 to 75% by weight of the total amount of calcium oxide (CaO) in the molten iron Divided CaO into 34 ~ 37kg / TP 28 ~ 40kg / T.P. Provided is a method for demolition of molten iron using desulfurized dust, wherein desulfurized dust containing CaO component is introduced into the molten iron so as to be 25-30% by weight of the total amount of calcium oxide (CaO) in the molten iron.
또한, 본 발명은 상기 CaO성분이 함유된 탈황더스트가 중량%로 CaO : 23∼32%, T.Fe : 25∼31%, SiO2: 2∼3%, MgO : 0.7∼2%, Al2O3: 0.8∼1%, C : 4∼10% 및 잔부 불가피한 불순물로 구성되는 것을 특징으로 하는 탈황더스트를 이용한 용선의 탈린방법을 제공한다.In the present invention, the desulfurized dust containing the CaO component is present in weight percent of CaO: 23-32%, T.Fe: 25-31%, SiO 2 : 2-3%, MgO: 0.7-2%, Al 2 Provided is a method for dechlorination of molten iron using desulfurized dust, which is composed of O 3 : 0.8 to 1%, C: 4 to 10%, and residual unavoidable impurities.
이하, 본 발명의 수치한정의 이유에 대하여 설명한다.Hereinafter, the reason for numerical limitation of this invention is demonstrated.
먼저, 용선중으로 전체 산화칼슘(CaO) 투입량의 25∼30중량%가 되도록 탈황더스트를 분CaO와 함께 용선중으로 투입하는 이유는 25중량% 이하로 탈황더스트가 첨가되는 경우에서는 종래에 비해 그 탈린효율이 좋지 않기 때문이며, 30중량% 이상으로 탈황더스트가 첨가되는 경우는 과도한 양의 투입으로 인해 탈린시간 및 탈린시의 용선온도가 떨어지기 때문이다.First, the reason why the desulfurization dust is added to the molten iron together with the powdered CaO to be 25-30% by weight of the total calcium oxide (CaO) input to the molten iron is less than 25% by weight when the desulfurization dust is added. This is because it is not good, if the desulfurization dust is added in more than 30% by weight because of the excessive amount of dephosphorization time and the molten iron temperature at the time of dephosphorization falls.
그리고, 소결반광의 투입량을 28∼40kg/T.P. 로 한정하는 이유는 28kg/T.P. 이하로 투입되면 용선중의 인과 충분한 반응을 일으키지 못하기 때문이고, 40kg/T.P. 이상 투입하면 필요치 이상으로 과다하게 투입되어 더 이상 그 효과가 증대되지 않기 때문이다.And the injection amount of sintered semi-reflective was 28-40 kg / T. The reason to limit to 28kg / T.P. If it is added below, it does not cause sufficient reaction with phosphorus in molten iron, and 40kg / T.P. This is because if the input is excessive, the input is excessively necessary and the effect is no longer increased.
또한, 탈황더스트를 함유한 분 CaO의 투입량을 34∼37kg/T.P. 로 한정한 이유는 34kg/T.P. 이하에서는 인산화물과의 반응이 부족하여 소결반광에 의해 형성된 인산화물이 다시 용선중으로 혼입하게 되고, 37kg/T.P. 이상을 투입하게 되면 역시 그 효과가 더 이상 증대되지 않기 때문이다.In addition, the amount of powdered CaO containing desulfurized dust was 34 to 37 kg / T.P. Limited to 34 kg / T.P. In the following, the reaction with the phosphate is insufficient, and the phosphate formed by the sintered semi-reflection is mixed again in the molten iron, and 37 kg / T.P. This is because the effect is not increased any more if the input.
이하, 실시예를 들어 본 발명을 보다 상세하게 설명한다.Hereinafter, an Example is given and this invention is demonstrated in detail.
[실시예]EXAMPLE
종래의 탈린처리방법과 본 발명에 의한 탈린처리방법을 비교하기 위하여 100kg의 유도로에 50kg의 용선을 장입하여 용해하였으며, 그 온도는 1400℃를 유지하였고, 탈린제의 투입량은 50kg의 용선을 고려하여 하기 표 1과 같이 투입하였다.In order to compare the desalination method according to the present invention with a conventional dephosphorization method, 50 kg of molten iron was charged and dissolved in a 100 kg induction furnace, and the temperature was maintained at 1400 ° C. Was added as shown in Table 1 below.
[표 1]TABLE 1
상기 투입되는 소결반광은 10중량%의 CaO를 함유하는 소결반광을 이용하였으며, 탈황더스트는 약 30중량%의 CaO를 함유하는 탈황더스트를 이용하였다.The injected sintered semi-reflective was used a sintered semi-reflective containing 10% by weight of CaO, desulfurized dust was used for the desulfurized dust containing about 30% by weight of CaO.
또한, 본 발명에서 도입되는 소결반광은 일반적으로 CaO성분이 5~ 10중량% 함유되면서 SiO2:3∼10중량%, Al2O3:1∼3중량%, MgO:1∼3중량%, T.Fe:55∼65중량% 및나머지는 Tracer로 구성되는 소결반광을 도입, 이용하였다.In addition, the sintered semi-reflective introduced in the present invention generally contains 5 to 10% by weight of CaO component, SiO 2 : 3 to 10% by weight, Al 2 O 3 : 1 to 3% by weight, MgO: 1 to 3% by weight, T.Fe: 55 to 65% by weight and the rest were introduced and used a sintered semi-reflective consisting of a tracer.
한편, 본 발명에서 이용하는 탈황더스트는 중량%로 CaO:23∼32%, T.Fe:25∼31%, SiO2:2∼3%, MgO:0.7∼2%, Al2O3:0.8∼1%, C:4∼10% 및 잔부 불가피한 불순물로 이루어지며, 소결광의 경우 20ea를 각각 제조하여 2분씩의 간격을 두고 투입하였고, 실험시간은 약 30분, 샘플간격은 약 3분씩으로 하여 각각의 변동추이를 조사하였다.On the other hand, the desulfurization dust used in the present invention in terms of weight% CaO: 23-32%, T.Fe: 25-31%, SiO 2 : 2-3%, MgO: 0.7-2%, Al 2 O 3 : 0.8- It is composed of 1%, C: 4 to 10%, and residual unavoidable impurities. In the case of sintered ore, 20ea were prepared and input at intervals of 2 minutes, and the experiment time was about 30 minutes and the sample interval was about 3 minutes, respectively. The trend of change was investigated.
이와 같은 실험의 결과 종래의 탈린방법으로는 도 1과 같은 Si, Mn, P, S 성분 변화가 이루어졌으며, 본 발명의 탈린방법에 의한 Si, Mn, P, S 성분의 변화는 도 2에 나타난 것과 같다.As a result of the experiment, the change of Si, Mn, P, and S components as shown in FIG. 1 was performed as a conventional dephosphorization method. Same as
도면에서 도시된 바와 같이, 탈린 전후 용선중의 인 성분은 종래법의 경우 0.102%에서 0.064%로 약 40% 정도의 탈린효율을 보인반면, 본 발명에 의한 경우는 0.093%에서 0.054%로 약 50% 정도의 탈린효율을 보임으로써 종래에 의한 방법보다 약 5∼10% 정도의 탈린효율이 향상되었음을 알 수 있다.As shown in the figure, the phosphorus component in the molten iron before and after Tallinn showed a delineation efficiency of about 40% from 0.102% to 0.064% in the conventional method, while in the present invention, from about 0.093% to 0.054% By showing the dephosphorization efficiency of about% it can be seen that the dephosphorization efficiency of about 5 to 10% improved than the conventional method.
상기와 같은 결과는 시간에 따른 용선중의 인 성분 거동을 초기 인성분으로 나누어서 백분율로 나타낸 도 3에서 보다 명확하게 나타내고 있다.The above results are shown more clearly in FIG.
즉, 본 발명의 특징은 용선중의 인과 직접적으로 반응하여 인산화물을 형성시키는 분체상태의 FeO 성분을 분 CaO와 함께 랜스를 통해 용선내부로 취입함으로써 반응계면적의 증대로 인해 인산화물의 형성을 보다 효율적으로 행할 수 있으며 이와 같이 인산화물이 형성된 즉시 분 CaO와 반응하여 안정한 화합물을 이룰 수 있게 하는 것이다.That is, the feature of the present invention is that the FeO component in the form of a powder which reacts directly with phosphorus in the molten iron is formed into the molten iron through the lance together with the powder CaO, thereby increasing the reaction surface area to form the phosphorus. This can be done efficiently and reacts with the powdered CaO as soon as the phosphate is formed to form a stable compound.
또한, 중량%로 CaO : 23∼32%, T.Fe : 25∼31%, SiO2: 2∼3%, MgO : 0.7∼2%, Al2O3: 0.8∼1%, C : 4∼10% 및 잔부 불가피한 불순물로 구성되는 탈황더스트의 첨가로 인해 종래 사용되던 분CaO 및 소결반광의 원단위를 절감할 수 있고, 분CaO의 융점을 하락시켜 유동성을 확보함으로써 종래 사용되던 형석을 사용하지 않게 되었다.In addition, by weight%, CaO: 23-32%, T.Fe: 25-31%, SiO 2 : 2-3%, MgO: 0.7-2%, Al 2 O 3 : 0.8-1%, C: 4-4 By adding desulfurization dust composed of 10% and residual unavoidable impurities, it is possible to save the raw unit of powdered CaO and sintered semi-glomerate used conventionally, and to reduce the melting point of powdered CaO to secure fluidity so as not to use conventionally used fluorite It became.
상기와 같은 본 발명에 의해 폐기되던 탈황더스트를 재활용하게 됨으로써 종래 사용되던 탈린제의 투입원단위를 저감할 수 있음은 물론 인과 직접적으로 반응하는 FeO 성분을 분체상태로 투입함으로써 탈린효율을 보다 향상시킬 수 있다.By recycling the desulfurized dust discarded by the present invention as described above, it is possible to reduce the input unit of the dephosphorization agent conventionally used, as well as to improve the dephosphorization efficiency by injecting the FeO component directly reacting with phosphorus in powder state. have.
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