KR20190027605A - Flux - Google Patents

Abstract

The present invention relates to a flux to stabilize slag generated from a steelmaking process. According to the present invention, the flux comprises a first raw material including waste pulp, and a second raw material including Na_2CO_3 and Na_2SO_4. Accordingly, according to one embodiment of the present invention, a melting point and viscosity of the slag are decreased by a sodium component, thereby stabilizing the slag to suppress sloping of flowing over the slag to the outside. Moreover, a large number of holes or channels are formed in the slag, and air is quickly discharged through the large number of holes or channels to prevent an increase in the volume of the slag, thereby stabilizing the slag to suppress or prevent sloping.

Description

Sedative {FLUX}

The present invention relates to a sedative agent, and more particularly, to a sedative agent capable of effectively inhibiting slag forming.

Chartered iron from the blast furnace is generally charged with scrap iron after the talline and desulfurization treatment in the pre-refining process. In order to remove C, Si, P, and Mn from the converter, oxygen is blown into the furnace using a lance, and calcium oxide (CaO) is added to the furnace for slagification.

When oxygen is blown into the furnace, silicon (Si) and phosphorus (P), which have relatively high oxygen affinity in the charcoal, first react with oxygen. At this time, silicon (Si) reacts with oxygen to produce SiO ₂ , and phosphorus (P) produces P ₂ O ₅ . The resulting SiO ₂ And P ₂ O ₅ are transferred to the slag in the molten bath surface and absorbed. Here, SiO _2, and is reacted with calcium oxide (CaO) charged into the initial blow, and thus the higher the viscosity of the slag.

When the primary winding is completed, the converter is tilted, the slag is discharged to the port (primary discharge), and the demolition and tallining of the charcoal are ended accordingly.

On the other hand, during the refinement of the converter, FeO, which is a main component of the slag, reacts with carbon in the molten steel, thereby generating a small amount of CO gas, that is, CO bubbles. The height of the slag in the converter is influenced by the rate of formation and disappearance rate of the CO bubbles. When the slag viscosity is high, the volume increases and overflows out of the converter.

However, since the viscosity of the slag is high at the beginning of the blowing process, a large amount of CO bubbles can not pass through the slag layer, thereby increasing the volume or volume of the slag, thereby rapidly increasing the slag foaming phenomenon. When such a slag forming phenomenon occurs rapidly, the slag overflows outside the slag port at the time of slag disposal.

Therefore, in order to prevent the problem of overflowing slag in the port, when the slag is discharged to the port, the sediment is injected into the slag in the port.

Conventionally used sedatives commonly include pulp pulp and carbonaceous materials. When this sediment is injected into the slag, holes are formed in the slag, and the CO gas is discharged to the atmosphere. Then, spraying water and nitrogen at high speed with the slag cooled the surface of the slag, thereby calibrating the slag forming by the principle of reducing surface area or volume.

However, these sedatives have the disadvantage of taking a long time to cool down the slag.

Korean Patent No. KR1206952B1

The present invention provides a sedative that can sedate the slag.

The present invention provides a sediment which can inhibit or prevent the overflow of slag from the port at the time of slag disposal.

The present invention relates to a sediment for sedimenting slag generated in a steelmaking process, comprising: a first raw material containing pulp pulp; And a second raw material containing sodium carbonate (Na ₂ CO ₃ ) and sodium sulfate (Na ₂ SO ₄ ).

The sedative agent comprises sodium carbonate (NaHCO ₃ ).

The second raw material may further include sodium chloride (NaCl).

The first raw material comprises 50% by weight to 90% by weight and the second raw material is 10% by weight to 50% by weight based on 100% by weight of the sedative agent.

It is preferable that the content of the sodium carbonate (Na ₂ CO ₃ ) is equal to the content of the sodium sulfate (Na ₂ SO ₄ ) or the content of the sodium sulfate (Na ₂ SO ₄ ) is larger than the content of the sodium carbonate (Na ₂ CO ₃ ) .

It is preferable that the content of the sodium carbonate (Na ₂ CO ₃ ) and the sodium sulfate (Na ₂ SO ₄ ) is larger than the content of the sodium chloride (NaCl).

The first raw material further includes a carbon-based raw material.

The second raw material is obtained from the desulfurization dust generated during the desulfurization of the flue gas generated during the production of the sintered ores.

The present invention relates to a method for producing a sediment that calms slag generated in a steelmaking process, comprising the steps of: preparing a first raw material containing waste pulp; Preparing a second raw material containing sodium carbonate (Na ₂ CO ₃ ) and sodium sulfate (Na ₂ SO ₄ ); And mixing and mixing the first raw material and the second raw material.

The second raw material further comprises sodium chloride (NaCl).

In the process of preparing the second raw material, it is obtained from the desulfurization dust generated during the desulfurization of the flue gas generated during the production of the sintered ores.

According to the sedative according to the embodiment of the present invention, the melting point and viscosity of the slag are reduced by the sodium component, so that the slag is soaked and the slag forming is suppressed.

When the sediment according to the embodiment is charged with slag, a large amount of holes or channels is formed in the slag. Then, the bubbles are rapidly discharged through a large number of holes or channels, so that the volume or volume of the slag is inhibited from increasing, so that the slag is settled and the slag formation is suppressed or reduced.

Further, according to the sedative according to the embodiment of the present invention, gas is generated by sodium carbonate (Na ₂ CO ₃ ) in addition to the conventional sedative, that is, the gas by the pulp pulp, More holes or channels are formed. Therefore, the bubbles in the slag are easily discharged as compared with the conventional method, so that the slug forming can be effectively suppressed or reduced.

1 is a block diagram showing a configuration of a sedative according to a first embodiment of the present invention;
The second is a block diagram showing the configuration of the sedative according to the second embodiment of the present invention
3 is an X-ray fluorescence spectrometry (XRF) graph showing the components of desulfurization dust
4 is a flow chart illustrating a method of producing a sedative according to an embodiment of the present invention
FIG. 5 is a photograph showing a result of the sediment input according to the conventional and the embodiment of the present invention

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art. It is provided to inform. Wherein like reference numerals refer to like elements throughout.

The present invention relates to a sedative capable of effectively suppressing the formation of slag. More particularly, the present invention relates to a sedative agent capable of effectively suppressing or preventing the problem of overflow of slag. In addition, the sedative according to the embodiment can be a sedimentation agent to be introduced into the slag in the port when discharging the slag in the converter to the port.

Hereinafter, with reference to Figs. 1 to 3, a method for producing a sedative and a sedative according to an embodiment of the present invention will be described.

1 is a block diagram showing the configuration of a sedative according to a first embodiment of the present invention. The second is a block diagram showing the configuration of the sedative according to the second embodiment of the present invention. 3 is an XRF (X-Ray Flourescence Spectrometry) graph showing the components of the desulfurizing dust. 4 is a flowchart showing a method for producing a sedative according to an embodiment of the present invention. 5 is a photograph showing a result of a sediment injection according to a conventional and an embodiment of the present invention.

The sedative according to an embodiment of the present invention includes sodium as a first raw material and a second raw material. Here, the first raw material includes pulp pulp, and the pulp pulp may be in the form of sludge. Pulp pulp is characterized by high water content. The first raw material may further contain carbon-based raw materials in addition to pulp pulp.

The second raw material according to the first embodiment includes sodium carbonate (Na ₂ CO ₃ ) and sodium sulfate (Na ₂ SO ₄ ) as shown in FIG. At this time, sodium carbonate (Na ₂ CO ₃₎ content and the sodium sulfate (Na ₂ SO ₄₎ compared to the amount of the sodium sulfate (Na ₂ SO ₄₎ is equal to or, wherein the sodium carbonate (Na ₂ CO ₃₎ content of preferably a number Do. More specifically, 10 wt% or more and 50 wt% or less of sodium carbonate (Na ₂ CO ₃ ) and 50 wt% or more and 90 wt% or less of sodium sulfate (Na ₂ SO ₄ ) are contained in 100 wt% .

The second raw material according to the first embodiment includes sodium carbonate (Na ₂ CO ₃ ) and sodium sulfate (Na ₂ SO ₄ ) as described above. However, the present invention is not limited thereto, and the second raw material may further include sodium chloride (NaCl) as in the second embodiment shown in FIG. At this time, sodium carbonate (Na ₂ CO _3), sodium sulfate comprises (Na ₂ SO ₄₎ and sodium chloride (NaCl), sodium carbonate (Na ₂ CO _3), and that the sodium chloride (NaCl) content of the sodium sulfate (Na ₂ SO ₄₎ Is more preferable than the content.

More specifically, the second raw materials other than the second embodiment include sodium carbonate (Na ₂ CO ₃ ), sodium sulfate (Na ₂ SO ₄ ), and sodium chloride (NaCl). At this time, sodium carbonate (Na ₂ CO ₃ ) is contained in an amount of 10 wt% or more, 45 wt% or less, 50 wt% or more and 90 wt% or less of sodium sulfate (Na ₂ SO ₄ ) % ≪ / RTI >

The second raw materials according to the first and second embodiments, that is, sodium carbonate (Na ₂ CO ₃ ), sodium sulfate (Na ₂ SO ₄ ), and sodium chloride (NaCl) are produced during the desulfurization of the exhaust gas generated during the sintering process Can be obtained by recovering the by-product obtained. In other words, the second raw material recycles by-products generated during desulfurization of the exhaust gas generated during the sintering process as a raw material for the sediment.

Hereinafter, the process of desulfurizing the sintered ores and the by-products will be briefly described.

When the blend material is charged into the bogie, the bogie proceeds in the sintering progressing direction and the sintering proceeds. At this time, suction force is generated in the wind box on the lower side of the truck, and the gas generated in the sintering process in the truck is transferred to the outside through the wind box and the duct connected to the wind box.

On the other hand, since the exhaust gas discharged from the vehicle contains SO _x (sulfur oxide) such as SO ₂ and SO _{3 which} are harmful to the environment, the exhaust gas can not be directly discharged to the outside. Therefore, a desulfurizing agent capable of collecting S (sulfur) in the duct or separating S (sulfur) from the exhaust gas is introduced, and generally, the desulfurizing agent includes sodium carbonate (NaHCO ₃ ).

Then, when the desulfurization proceeds by the reaction between the desulfurizing agent containing sodium carbonate (NaHCO ₃ ) and the exhaust gas, the desulfurization byproduct usually contains sodium carbonate (Na ₂ CO ₃ ) and sodium sulfate (Na ₂ SO ₄ ), And may further include sodium chloride (NaCl). More particularly, the desulfurizing dust 100 wt%, 10 wt% or more and 50% by weight sodium carbonate (Na ₂ CO ₃₎ and of 50% by weight or more, or containing sodium sulfate of at most 90 wt% (Na ₂ SO _4), (Na ₂ CO ₃ ), 50% by weight or more, 90% by weight or less of sodium sulfate (Na ₂ SO ₄ ), 1 or more and 10 or less by weight based on 100% Or less by weight of sodium chloride (NaCl).

In this embodiment, the thus generated desulfurization dust is utilized as a second raw material.

Conventionally, when desulfurizing dust is used as a raw material of a desulfurizing dust as in the present invention, industrial by-products or waste are recycled, thereby reducing the cost of preparing a sedative.

Of course, the second raw material is not limited to the recycling of the desulfurizing dust but may be prepared by separately preparing sodium carbonate (Na ₂ CO ₃ ), sodium sulfate (Na ₂ SO ₄ ) and sodium chloride (NaCl) May be produced.

In the case of using the second raw material according to the first and second embodiments, it was confirmed that the S (sulfur) concentration of the slag in the port due to the sodium sulfate in the sediment was less than the amount of slag in the port and increased by 0.1% It is considered that there is no environmental problem in slag recycling.

On the other hand, the sodium carbonate (Na ₂ CO ₃ ) contained in the second raw material is synthesized in the form of sodium hydrogencarbonate (NaHCO ₃ ) when it comes into contact with water. Since pulp contained in the first raw material has a high water content, when the first raw material and the second raw material are mixed, the sodium carbonate (Na ₂ CO ₃ ) of the second raw material is converted into sodium hydrogencarbonate (NaHCO ₃ ) do. When the sediment is injected into the slag, the moisture adhered to sodium hydrogencarbonate (NaHCO ₃ ) meets the slag at a high temperature and generates a gas such as CO gas, thereby making a large amount of holes or channels in the slag. Then, bubbles, such as CO bubbles, are rapidly discharged through holes or channels. At this time, the sedative according to the embodiment is a low melting point material having a melting point of 650 ° C to 900 ° C, and when introduced into slag, it has an effect of reducing the melting point at the interface and accelerating the discharge of bubbles. With this bubble discharge, the volume or volume of the slag is inhibited from increasing, and thus the slag is settled. That is, if the fine bubbles inside the slag are not discharged to the outside of the slag, the volume or the volume of the slag increases, causing a sloping problem in which the slag overflows, so that the bubbles in the slag can be easily discharged So that slag foaming can be suppressed or reduced.

In addition, when the sodium component of the second raw material is introduced into the slag, the melting point and the viscosity of the slag are lowered to suppress the slag forming.

Hereinafter, with reference to FIG. 4, a method for producing a sedative according to an embodiment of the present invention will be described.

First, a first raw material containing waste pulp and a second raw material containing sodium carbonate (Na ₂ CO ₃ ), sodium sulfate (Na ₂ SO ₄ ) and sodium chloride (NaCl) are prepared (S 110, S 120). Here, the first raw material may further contain a carbonaceous raw material in addition to the pulp pulp.

Then, the first raw material and the second raw material are mixed (S200), and the mixture is bulked in a briquetting manner (S300). At this time, the first raw material is mixed in an amount of 50 wt% or more and 90 wt% or less, and the second raw material is contained in an amount of 10 wt% or more and 50 wt% or less, based on 100 wt% of the sediment.

On the other hand, when the second raw material is less than 10% by weight, the effect of suppressing slag foaming is similar to that of the prior art, and a more effective slagging effect is not exhibited. Therefore, the second raw material is contained in an amount of 10 wt% or more. On the contrary, when the second raw material exceeds 50% by weight, the slag foaming inhibiting effect is superior to that of the conventional sedative, but the slag boiling phenomenon due to the sodium component is severe after the sediment is charged, which makes it difficult to secure the stability of the operation. After mixing the first raw material and the second raw material, it is difficult to agglomerate the first raw material and the second raw material. Therefore, the second raw material is contained in an amount of 50 wt% or less.

When the first raw material and the second raw material are mixed and agglomerated, sodium carbonate (Na ₂ CO ₃ ) contained in the second raw material is converted into sodium hydrogencarbonate (NaHCO ₃ ) together with the moisture of the pulp pulp.

In the massification of the mixture of the first raw material and the second raw material, the mixture is agglomerated to have a particle size of 1 mm to 200 mm.

For example, when the sediment is less than 1 mm, a flame may be generated when the sediment is introduced into the slag, and the slag can not be effectively introduced into the slag due to the flame and the heat. On the contrary, when the sediment is more than 200 mm, the time spent in reacting with the slag is prolonged even if the slag is poured into the slag, so that the soothing effect is reduced.

Thus, in the embodiment, the sediment is massivated to have a particle size of 1 mm to 200 mm.

When the sediment is introduced into the slag, the moisture adhered to sodium bicarbonate (NaHCO ₃ ) meets with the high-temperature slag and generates gas, thereby making a large amount of holes or channels in the slag. Then, bubbles, such as CO bubbles, are rapidly discharged through holes or channels. With this bubble discharge, the volume or volume of the slag is inhibited from increasing, and thus the slag is settled. That is, if the fine bubbles inside the slag are not released to the outside of the slag, the volume or volume of the slag increases and the slag overflows. The bubbles in the slag can be easily discharged by the sediment according to the embodiment, Can be suppressed or prevented.

Hereinafter, a charcoal refining process using a sedative according to an embodiment of the present invention will be described.

First, charcoal and scrap, which have been subjected to at least one pre-refining of desulfurization and talline, are charged into the converter.

Then, oxygen is blown into the converter using a lance (primary blowing), and calcium oxide (CaO) is added for slagification. When oxygen is blown into the furnace, silicon (Si) and phosphorus (P), which have relatively high oxygen affinity in the charcoal, first react with oxygen. At this time, silicon (Si) reacts with oxygen to produce SiO ₂ , and phosphorus (P) produces P ₂ O ₅ . The resulting SiO ₂ and P ₂ O ₅ are transferred to the slag in the molten bath surface and absorbed. Here, SiO _2, and is reacted with calcium oxide (CaO) charged into the initial blow, and thus the higher the viscosity of the slag.

When the swirling is finished, the converter is tilted, and the slag is discharged to the port.

On the other hand, during the refinement of the converter, FeO, which is a main component of the slag, reacts with carbon in the molten steel, thereby generating a small amount of CO gas, that is, CO bubbles. However, in particular, since the viscosity of the slag is high at the beginning of the blowing operation, if the large amount of CO bubbles can not pass through the slag layer, the slag volume or volume increases and the slag foaming phenomenon increases sharply. When such a slag forming phenomenon occurs rapidly, the slag overflows outside the slag port at the time of slag disposal.

Therefore, when discharging the slag to the port, the flux is injected into the slag in the port. At this time, the sediment is put in an amount of 5 kg to 20 kg per ton of slag. At this time, the sedative can be injected one time or divided into a plurality of circuits.

When the sediment is introduced into the slag, the sodium carbonate (Na ₂ CO ₃ ) of the second raw material and the water contained in the pulp pulp of the first raw material are mixed with each other, and moisture adhered to the formed sodium hydrogencarbonate (NaHCO ₃ ) And CO gas is generated, thereby forming a large amount of holes or channels in the slag. Then, the bubbles are rapidly discharged through a large number of holes or channels, so that the volume or volume of the slag is inhibited from increasing, and thus the slag is settled.

That is, according to the sedative according to the embodiment of the present invention, as the gas of the second raw material sodium carbonate (Na ₂ CO ₃ ) is generated in addition to the conventional sedative, that is, the gas by the pulp pulp, (See Fig. 5A) in which a sediment made of a carbon-based material is injected, holes or channels through which bubbles can be discharged are formed. Therefore, the bubbles in the slag can be easily discharged as compared with the prior art, so that the slug forming can be effectively suppressed or prevented (see FIG. 5B).

S110: First raw material preparation S120: Second raw material preparation
S200: mixing of the first raw material and the second raw material
S300: Molding

Claims (11)

As a sedative that calms the slag generated in the steelmaking process,
A first raw material containing pulp pulp; And
A second raw material containing sodium carbonate (Na ₂ CO ₃ ) and sodium sulfate (Na ₂ SO ₄ );
≪ / RTI > The method according to claim 1,
The sedatives are depressants, including the carbonation of sodium (NaHCO _3). The method of claim 2,
Wherein the second raw material further comprises sodium chloride (NaCl). The method according to any one of claims 1 to 3,
Wherein the first raw material comprises 50 wt% to 90 wt% and the second raw material is 10 wt% to 50 wt%, based on 100 wt% of the sedative agent. The method of claim 4,
Wherein the content of the sodium carbonate (Na ₂ CO ₃ ) is equal to the content of the sodium sulfate (Na ₂ SO ₄ ) or the amount of the sodium sulfate (Na ₂ SO ₄ ) is larger than the content of the sodium carbonate (Na ₂ CO ₃ ). The method of claim 4,
Wherein the content of the sodium carbonate (Na ₂ CO ₃ ) and the sodium sulfate (Na ₂ SO ₄ ) is larger than the content of the sodium chloride (NaCl). The method according to any one of claims 1 to 3,
Wherein the first raw material further comprises a carbonaceous raw material. The method according to any one of claims 1 to 3,
Wherein the second raw material is obtained from a desulfurizing dust generated during desulfurization of the exhaust gas generated during the production of the sintered ores. A method for producing a sediment that calms slag generated in a steelmaking process,
Preparing a first raw material containing pulp pulp;
Preparing a second raw material containing sodium carbonate (Na ₂ CO ₃ ) and sodium sulfate (Na ₂ SO ₄ ); And
Mixing the first raw material and the second raw material, and molding the mixture;
≪ / RTI > The method of claim 9,
Wherein the second raw material further comprises sodium chloride (NaCl). The method according to claim 9 or 10,
Wherein the second raw material is obtained from the desulfurization dust generated during the desulfurization of the flue gas generated during the production of the sintered ores.

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