KR100267270B1 - The reducing method of mangaese ore - Google Patents

The reducing method of mangaese ore Download PDF

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KR100267270B1
KR100267270B1 KR1019960056456A KR19960056456A KR100267270B1 KR 100267270 B1 KR100267270 B1 KR 100267270B1 KR 1019960056456 A KR1019960056456 A KR 1019960056456A KR 19960056456 A KR19960056456 A KR 19960056456A KR 100267270 B1 KR100267270 B1 KR 100267270B1
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manganese
ore
slag
molten steel
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KR19980037663A (en
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박종민
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이구택
포항종합제철주식회사
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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
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/0006—Adding metallic additives
    • 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
    • C21C5/52—Manufacture of steel in electric furnaces
    • C21C5/5241—Manufacture of steel in electric furnaces in an inductively heated furnace

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Treatment Of Steel In Its Molten State (AREA)

Abstract

PURPOSE: A method for increasing costly manganese recovery ratio in the steelmaking process for manufacturing Mn-rich steel is provided. CONSTITUTION: A pig iron comprising C 4.3-4.5wt.%, Mn 0.2-0.25wt.% is melted in a high frequency induction furnace and then a steelmaking slag comprising CaO 55wt.%, SiO2 15wt.%, FeO 20wt.%, MnO 5wt.%, MgO 5wt.% is melted therein. Briquette ore is poured in molten slag in the temperature range of 1500±10. The time required to completely melt the briquette ore into the steelmaking slag is measured, and if completely smelted, collected sample ore is analyzed to obtain manganese content of collected sample ore. Through above procedures, manganese recovery ratio is obtained by the follow equation: recovery ratio of manganese=(the amount of manganese recovered into molten steel through reduction)/(the amount of manganese in briquette ore)x100(%).

Description

망간 회수율을 향상시킬 수 있는 망간 광석의 환원방법Reduction method of manganese ore to improve manganese recovery

본 발명은 고망간강 제조를 위한 제강공정에서의 망간광석의 환원방법에 관한 것으로서, 보다 상세하게는 망간광석의 슬래그화를 촉진시키면서 유효원소인 망간의 회수율을 향상시킬 수 있는 제강공정에서의 망간회수율 향상 방법에 관한 것이다.The present invention relates to a method for reducing manganese ore in a steelmaking process for producing high manganese steel, and more particularly, to a method for reducing manganese ore in a steelmaking process capable of improving the recovery of manganese as an effective element while promoting slagging of manganese ore. Improvement method.

망간은 철강의 강도를 향상시키는 유효한 원소이기 때문에 산화공정인 제강공정에서 최대한 망간의 산화를 억제시킬 뿐만 아니라 용도에 맞춰 고가의 합금철인 페로망간을 첨가하여 망간의 성분을 조정하고 있다. 따라서 합금철의 사용량을 감소시키는 것이 제강생산 원가를 낮추는 주요한 요인으로 작용하며, 최근에는 망간광석을 용선을 정련하는 제강로에 첨가하여 이를 환원시킴으로써 합금철의 사용량을 감소시키는 기술이 시도되고 있다.Since manganese is an effective element for improving the strength of steel, it not only suppresses oxidation of manganese as much as possible in the steelmaking process, which is an oxidation process, but also adjusts the composition of manganese by adding ferro-manganese, which is an expensive ferro- Therefore, reducing the amount of ferroalloys is a major factor in lowering steelmaking costs. Recently, attempts have been made to reduce the amount of ferroalloys by adding manganese ore to a steelmaking furnace to refine them.

이와같은 망간광석의 환원 방법으로는, 정광의 망간광석을 제강로에 투입하는 방법이 가장 널리 사용되고 있다. 이러한 방법은 망간광석 투입량이 적은 경우에는 망간광석이 쉽게 슬래그 중에 용해되어 충분하게 반응이 이루어지나, 그 투입량이 많아짐에 따라 슬래그 중에 용해되는 비율이 감소하게 되고 이에 따라 망간회수율도 감소하게 되는 문제점이 있다. 망간광석의 용해를 촉진시키는 방법으로서 망간광선 분체를 제강로에 취입하는 방법이 있으나, 분체를 취입하는 설비를 건설하고 유지해야 하는 경제적 부담이 클 뿐만 아니라 먼지가 많이 발생하여 조업환경을 나쁘게 하는 문제점이 있다.As a method for reducing such manganese ore, a method of putting manganese ore as a concentrate into a steelmaking furnace is most widely used. In this method, manganese ore easily dissolves in the slag when the amount of manganese ore is small, and the reaction is sufficiently carried out. However, as the amount of the manganese ore is small, the rate of dissolution in the slag decreases, have. As a method for promoting the dissolution of manganese ore, there is a method of blowing manganese light powder into the steelmaking furnace. However, there is a great economical burden to construct and maintain a facility for blowing powder, .

따라서, 본 발명은 종래의 제강공정에서의 망간광석 환원방법의 문제점을 개선하기 위하여 창안된 것으로서, 망간광석을 함유하는 조성물로 구성된 단광을 제강로에 투입함으로써 망간광석이 슬래그 중에 쉽게 용해되어 망간회수율을 증가시킬 수 있는 환원 방법을 제공하는 데에 그 목적이 있다.Accordingly, the present invention has been made in order to solve the problems of the manganese ore reduction method in the conventional steelmaking process, and the manganese ore is easily dissolved in the slag by injecting a single light composed of the composition containing manganese ore into the steelmaking furnace, And a reducing method capable of increasing the amount of the reducing agent.

제1도는 망간광선 단관중 산화규소의 함량과 용해시간의 관계를 나타내는 그래프.FIG. 1 is a graph showing the relationship between the content of silicon oxide and the dissolution time in a single manganese beam.

제2도는 망간광석 단광중 산화규소의 함량과 망간회수율의 관계를 나타내는 그래프.FIG. 2 is a graph showing the relationship between the content of silicon oxide and manganese recovery in manganese ore.

제3도는 망간광석 단관중 알루미나의 함량과 망간회수율의 관계를 나타내는 그래프.FIG. 3 is a graph showing the relationship between the content of alumina and the recovery of manganese in a single manganese ore.

상기의 목적을 달성하기 위하여, 본 발명은 제강로에서 망간광석을 환원시키는 방법에 있어서,In order to accomplish the above object, the present invention provides a method for reducing manganese ore in a steelmaking furnace,

고주파유도로에서 탄소:4.3-4.5%, 망간:0.2-0.25%의 조성을 갖는 선철을 용해시키고, CaO:55%, SiO2:15%, FeO:20%, MnO:5%, MgO:5%의 조성을 갖는 제강슬래그를 용해시킨 후, 용강온도를 1500±10℃로 유지하면서 단광을 용해된 슬래그중에 투입시키고, 상기 단광이 상기 슬래그중으로 완전히 용해될 때까지의 시간을 측정하여 일정시간이 경과되면 용강 시료를 채취한 후 시료중의 망간함량을 분석하여 망간회수율을 (용강중으로 환원회수된 망간량)/(단광중인 망간량) × 100(%) 식으로 산정하는 것을 특징으로 하는 망간광석의 환원방법을 제공한다.4.3-4.5%, manganese: carbon from a high-frequency induction was dissolved iron having a composition of 0.2-0.25%, CaO: 55%, SiO 2 : 15%, FeO: 20%, MnO: 5%, MgO: 5% The molten steel slag is melted and the molten steel temperature is maintained at 1500 占 10 占 폚 and the single light is introduced into the melted slag and the time until the single light is completely dissolved in the slag is measured, The manganese content in the sample is analyzed by collecting the molten steel sample, and the manganese recovery rate is calculated by the formula (manganese content reduced to manganese in molten steel) / (manganese content in single manganese) × 100 (%). ≪ / RTI >

제강로에 망간광석이 투입되면, 우선 제강슬래그에 함유되어 있는 철산화물이 광석입자의 표층에 침투하여 망가노뷔스타이트(Mangano-wustite)를 형성시킨다. 이 망가노뷔스타이트는 융점이 높을 뿐만 아니라 제강조업온도에서 점성이 크기 때문에 망간광석입자들은 서로 응집되어 큰 괴상으로 성장하여 조업이 진행되는 동안에 슬래그중으로 충분히 용해되지 못한다. 따라서, 망간광석을 정광 상태로 투입하는 것은 망간회수율을 충분히 얻기가 어렵다. 반면에 산화규소와 알루미나를 혼합한 단광은 망가노뷔스타이트의 융점을 낮추어 망간광석이 슬래그중으로 쉽게 용해되도록하여 망간회수율을 향상시키는 것이다. 그러나, 산화규소는 상술한 바와 같이 망가노뷔스타이트의 용해를 촉진시키는 작용을 하는 반면에 평형론적으로는 망간산화물의 환원을 억제시키는 역할을 하는 양면성을 가지고 있다. 따라서, 산화규소가 과량으로 오히려 망간회수율을 감소시키는 역할을 하기 때문에 적정량이 함유되어야 하는 것이다.When manganese ore is introduced into the steelmaking furnace, the iron oxide contained in the steel making slag first penetrates into the surface layer of ore particles to form Mangano-wustite. Since the manganovisite has a high melting point and is viscous at the steelmaking temperature, the manganese ore particles aggregate with each other and grow into a large mass and are not sufficiently dissolved in the slag during the operation. Therefore, it is difficult to obtain the manganese recovery rate sufficiently by putting the manganese ore in the concentrate state. On the other hand, a single light mixed with silicon oxide and alumina lowers the melting point of manganovistite, thereby allowing the manganese ore to easily dissolve in the slag, thereby improving the manganese recovery rate. However, silicon oxide acts to promote the dissolution of manganovisite as described above, while it has a dual aspect that plays a role in inhibiting the reduction of manganese oxide in equilibrium. Therefore, it is necessary that an adequate amount of silicon oxide is contained because silicon oxide plays an excessive role in reducing manganese recovery.

이하, 본 발명에 따른 방법에서 사용되는 조성물의 수치한정 이유에 대하여 설명한다. 산화규소가 30% 미만인 경우에는 산화규소가 망간산화물을 용이하게 용해시킴으로써 망간회수율을 향상시키는 반면에 30% 이상인 경우에는 산화규소가 망간산화물의 환원반응을 억제하여 망간회수율을 떨어뜨리는 불건전한 작용을 하므로 산화규소를 30% 이내로 제한하는 것이 바람직하다. 또한 알루미나가 5% 미만인 경우에는 알루미나가 망간산화물이 쉽게 용해되도록 하여 망간산화물의 환원반응을 촉진시키는 반면에 5% 이상에서는 오히려 융점을 상승시켜 용해속도를 감소시킬 뿐만아니라 산화규소의 경우와 마찬가지로 슬래그의 염기도를 저하시킴으로써 망간산화물의 환원반응을 억제하여 망간회수율을 감소시키는 문제점이 있으므로 5% 이내가 적절하다.Hereinafter, the reasons for limiting the numerical value of the composition used in the method according to the present invention will be described. When the amount of silicon oxide is less than 30%, the silicon oxide easily dissolves the manganese oxide to improve the recovery of manganese. On the other hand, when the silicon oxide is more than 30%, the silicon oxide suppresses the reduction reaction of manganese oxide, It is preferable to limit the silicon oxide to 30% or less. In addition, when alumina is less than 5%, alumina easily dissolves manganese oxide, thereby promoting the reduction reaction of manganese oxide. On the other hand, when the alumina content is more than 5%, the melting point is increased to lower the dissolution rate. The reduction of manganese oxide is suppressed, thereby reducing the manganese recovery. Therefore, it is appropriate that the manganese content is within 5%.

이하, 실시예를 통하여 본 발명을 보다 상세히 설명한다.Hereinafter, the present invention will be described in more detail by way of examples.

[실시예 1][Example 1]

50kg 이상이 MnO2로 구성되는 망간광석과 99.9% 이상이 SiO2인 산화규소를 하기 표 1의 조성비로 혼합하여 0.1mm 이하의 입도로 분쇄한 뒤 10mm의 직경을 갖는 실린더형 몰드에 넣고 1톤/㎠ 의 압력으로 압축하여 직경이 10mm 이고 높이가 10±1mm인 원통형 단광을 제조하였다.Manganese ores composed of MnO 2 of 50 kg or more and silicon oxide of 99.9% or more of SiO 2 were mixed at the composition ratios shown in Table 1, ground to a particle size of 0.1 mm or less, put into a cylindrical mold having a diameter of 10 mm, / Cm < 2 > to produce a cylindrical single beam having a diameter of 10 mm and a height of 10 1 mm.

50kg 고주파유도로에서 탄소:4.3-4.5%, 망간:0.2-0.25%의 조성을 갖는 선철 40kg을 용해한 후, CaO:55%, SiO2:15%, FeO:20%, MnO:5%, MgO:5%의 조성을 갖는 제강슬래그 1.2kg을 용해시킨 후, 용강온도를 1500±10℃로 유지하면서 단광 400g을 용해된 슬래그중에 투입하였다. 단광 투입은 4분동안 4회로 나누어 각각 100g 씩 수작업으로 진행되었으며, 400g의 단광을 모두 투입한 후부터 단광이 슬래그중으로 완전히 용해될 때까지의 시간을 측정하여 정하였다. 시간을 측정하기 시작한 후부터 10분이 경과한 후에 용강 시료를 채취하여 시료중의 망간함량을 화학분석하여 망간회수율을 산정하였다.40 kg of pig iron having a composition of 4.3-4.5% carbon and 0.2-0.25% carbon was dissolved in a 50 kg high-frequency induction furnace and then CaO: 55%, SiO 2 : 15%, FeO: 20%, MnO: 5%, MgO: 1.2 kg of a steelmaking slag having a composition of 5% was melted and then 400 g of monoaxial light was introduced into the molten slag while maintaining the molten steel temperature at 1500 占 10 占 폚. The amount of the single light was divided into 4 steps for 4 minutes, and each 100 g was manually performed. The time from when all the 400 g of the single light was introduced to when the single light was completely dissolved into the slag was measured and determined. After 10 minutes from the start of measuring the time, the molten steel samples were sampled and the manganese content in the samples was chemically analyzed to calculate the manganese recovery rate.

[표 1][Table 1]

상기 방법으로 얻어진 산화규소의 함유량에 따른 단광의 용해시간의 변화를 표와 도1에, 망간환원회수율의 변화를 표1과 도2에 나타내었다. 도1 및 도2에서 P는 종래방법, A는 본발명 방법A, B는 본발명 방법B, C는 본발명 방법C, D는 본발명 방법D, A+는 비교방법A, B+는 비교방법B, 그리고 C+는 비교방법C를 나타낸다. 여기에서, 망간회수율은 다음식과 같이 단광이 함유하고 있는 망간중에 환원되어 용선으로 혼입된 양의 비를 나타낸 것을 의미하며 값이 클수록 망간회수율이 우수함을 의미한다.The changes in the dissolution time of the single light according to the content of silicon oxide obtained by the above method are shown in Table 1, and the changes in the manganese reduction recovery rate are shown in Table 1 and Fig. 1 and 2, P represents the conventional method, A represents the present invention method A, B represents the inventive method B, C represents the inventive method C, D represents the inventive method D, A + , And C + represents the comparison method C. Here, the manganese recovery rate means that the amount of manganese contained in the manganese contained in the manganese is reduced to the amount of manganese incorporated into the molten manganese as shown in the following formula. The larger the value, the better the recovery of manganese.

도1을 참조하면, 용해시간은 산화규소의 함량이 증가함에 따라 급격히 감소하여, 산화규소 함량이 40% 이상이 되면 다시 급격히 증가하는 현상을 보이고 있다.Referring to FIG. 1, the dissolution time rapidly decreases as the content of silicon oxide increases, and when the silicon oxide content exceeds 40%, the dissolution time rapidly increases again.

그리고 도2를 참조하면, 망간회수율은 산화규소 함량이 20%일 때까지(본 발명방법 A, B, C)는 용해시간이 감소함에 따라 증가하나, 20% 이후에는 오히려 감소하며, 30%일 때(본 발명방법 D)는 산화규소가 함유되지 않은 망간광석만을 투입한 종래방법과 유사하게 나타나며 30%이상(비교방법 A, B, C)에서는 종래방법보다도 낮은 값을 나타냈음을 알 수 있다. 이와 같이 본 발명 방법이 종래방법 및 비교방법보다 망간회수율이 높은 망간광석 환원처리방법인 것이다.Referring to FIG. 2, the recovery of manganese increases with decreasing dissolution time until the silicon oxide content reaches 20% (Methods A, B and C of the present invention), but decreases after 20% (Method D of the present invention) is similar to the conventional method in which only manganese ore containing no silicon oxide is added, and it is understood that the value is lower than 30% (Comparative Methods A, B and C). Thus, the method of the present invention is a manganese ore reduction method having a higher manganese recovery rate than the conventional method and the comparative method.

[실시예 2][Example 2]

상기 실시예 1에서 산화규소를 30% 이내로 함유된 단광을 투입하는 것이 정광을 첨가하는 것보다 우수한 방법임을 알 수 있었다. 본 실시예에서는 알루미나가 망간회수율에 미치는 영향을 구하기 위하여, 실시예 1과 동일한 방법으로 하기 표2의 조성물들을 취입하여 얻은 처리후의 망간회수율을 표2와 도3에 함께 나타내었다.It was found that the introduction of the single light containing silicon oxide within 30% in Example 1 was superior to the addition of the concentrate. In this example, the recovery of manganese after the treatment of the compositions of Table 2 below in the same manner as in Example 1 is also shown in Tables 2 and 3 in order to determine the effect of alumina on the manganese recovery.

[표 2][Table 2]

도3에서, P는 종래방법, C는 본발명 방법C, E는 본발명 방법E, F는 본발명 방법F, D+는 종래방법D, 그리고 E+는 종래방법E를 나타낸다.In FIG. 3, P represents the conventional method, C represents the present invention method C, E represents the inventive method E, F represents the inventive method F, D + represents the conventional method D, and E + represents the conventional method E.

상기 표2와 도3에 나타난 바와 같이, 알루미나가 5% 이내로 함유된 경우(본 발명방법 E, F, G)가 종래방법과 알루미나가 5%이상 함유된 경우(비교방법 D, E)보다 높은 망간회수율을 나타내고 있다. 따라서, 망간광석과 산화규소의 배합에 5%이내의 알루미나를 첨가하는 것은 망간회수율을 향상시키는 방법임을 알 수 있다.As shown in Table 2 and FIG. 3, when the content of alumina is less than 5% (Methods E, F and G of the present invention) is higher than those of the conventional method and alumina containing 5% Manganese recovery rate. Therefore, it can be seen that the addition of less than 5% alumina to the combination of manganese ore and silicon oxide is a method for improving the manganese recovery.

상술한 바와 같이, 본 발명은 제강로에서 투입된 망간광석의 환원회수율을 향상시킴에 의해 용강망간의 함량을 증가시킴으로써 고가의 페로망간 합금철의 투입량을 절감하여 용강 제조원가를 낮출 수 있는 우수한 효과가 있는 것이다.INDUSTRIAL APPLICABILITY As described above, the present invention improves the reduction recovery rate of manganese ore introduced from a steelmaking furnace, thereby increasing the content of manganese manganese, thereby reducing the amount of expensive ferro-manganese ferroalloy input, will be.

Claims (1)

제강로에서 망간광석을 환원시키는 방법에 있어서,A method for reducing manganese ore in a steelmaking furnace, 고주파유도로에서 탄소:4.3-4.5%, 망간:0.2-0.25%의 조성을 갖는 선철을 용해시키고, CaO:55%, SiO2:15%, FeO:20%, MnO:5%, MgO:5%의 조성을 갖는 제강슬래그를 용해시킨 후, 용강온도를 1500±10℃로 유지하면서 단광을 용해된 슬래그중에 투입시키고, 상기 단광이 상기 슬래그중으로 완전히 용해될 때까지의 시간을 측정하여 일정시간이 경과되면 용강 시료를 채취한 후 시료중의 망간함량을 분석하여 망간회수율을 (용강중으로 환원회수된 망간량)/(단광중인 망간량) × 100(%) 식으로 산정하는 것을 특징으로 하는 망간광석의 환원방법.4.3-4.5%, manganese: carbon from a high-frequency induction was dissolved iron having a composition of 0.2-0.25%, CaO: 55%, SiO 2 : 15%, FeO: 20%, MnO: 5%, MgO: 5% The molten steel slag is melted and the molten steel temperature is maintained at 1500 占 10 占 폚 and the single light is introduced into the melted slag and the time until the single light is completely dissolved in the slag is measured, The manganese content in the sample is analyzed by collecting the molten steel sample, and the manganese recovery rate is calculated by the formula (manganese content reduced to manganese in molten steel) / (manganese content in single manganese) × 100 (%). Way.
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