WO2014003306A1 - Reduced slag ball pre-melt flux for ladle furnace and method for manufacturing same - Google Patents

Abstract

The present invention relates to a reduced slag ball pre-melt flux and to a method for manufacturing same, wherein a reduced slag ball pre-melt flux is manufactured for recycling ladle furnace reduced slag (LF slag), which is a waste product generated from the secondary refining process of a steel mill, by reducing the components of phosphorus (P), sulfur (S), etc. in a ladle furnace process to thereby be easily applied to the manufacture of clean steel. More particularly, the present invention relates to a reduced slag ball pre-melt flux for ladle furnace and to a method for manufacturing same characterized in that melted LF slag is manufactured in a ball shape with spherical particles by dropping melted LF slag from inside a slag pot onto a turn dish and by quenching melted LF slag during said dropping by atomizing high pressure gas from an atomizer nozzle, wherein the reduced slag ball pre-melt flux is characterized in that it uses an LF slag ball containing 12 wt% or less of SiO₂, 35 to 66 wt% of CaO, 10 to 40 wt% of Al₂O₃, 10 wt% or less of MgO, 5 wt% or less of MnO, 10 wt% or less of T-Fe, and 1 wt% or less of TiO₂ as main ingredients, and in that it uses an LF slag ball having a spherical shape of 0.9 to 1.0 sphericity, and having a particle size of 5.0 mm or smaller.

Description

Steelmaking slag ball preparation and its manufacturing method

The present invention is a reduced slag ball preparation (Flux: 造 滓 劑) manufactured to recycle LF slag, which is a waste generated during the secondary refining process of a steel mill, and phosphorus (P) in the steelmaking process. The present invention relates to a reducing slag ball preparation agent and a method for manufacturing the same, which are easily utilized for the production of clean steel by reducing components such as sulfur and sulfur (S), and more particularly, turning steel reduction slag in a molten slag pot. The molten steel reduction slag is made into a ball shape of spherical particles by dropping it on a dish and quenching by spraying a high pressure gas from an atomizer nozzle onto the falling steelmaking reduction slag. The weight percent contains 12 wt% or less of SiO ₂ , 35 to 66 wt% of CaO, 10 to 40 wt% of Al ₂ O _3, 10 wt% or less of MgO, 5 wt% or less of MnO, 10 wt% or less of T-Fe, and 1 wt% or less of TiO ₂ . , Spherical in shape This invention relates to a steelmaking reducing slag ball preparation using a steelmaking reducing slag ball (LF slag ball), characterized in that the spherical degree is 0.9 to 1.0, the particle diameter is 5.0mm or less, and a manufacturing method thereof.

In general, slag preparations include soda ash, quicklime, and sintered ore, and carbon (C), manganese (Mn), phosphorus (P), and sulfur (S) generated during the refining of molten steel during steelmaking in steel mills. To control impurities by removing impurities such as silicon (Si), lowering slag to improve slag fluidity and improving cleanliness of steel, and to facilitate separation from non-metallic inclusions in molten steel. At the same time, it is known that an impurity contained in the slag with the passage of time is prevented from diffusing again into the river, thereby producing high quality steel.

Typically, quicklime (CaO), which is used as a slag aid, is produced by heating limestone at a constant temperature in a calcination furnace. The molten steel is easily separated by improving fluidity in an electric furnace melting process, and slag is formed to absorb and remove various impurities. It is used in a large amount with other materials in the process, but its property is formed as powder as shown in FIG. 1, and it is easily changed and is highly hydrated. The use of airtight containers must be used during transportation and storage, so their use is limited and they are inadequate for their role as preparations.

In addition, when the contact with water causes a chemical reaction and expands the volume, when used as a road aggregate or concrete substitute, it causes cracks and its use is extremely limited. In addition, due to the characteristics of the powder due to differentiation, when re-injection into the subsidiary materials generated dust due to scattering or inhaled in the dust collector, its use was difficult.

The present invention is a reduced slag ball manufactured by recycling steelmaking reducing slag, which is a waste generated in the secondary refining process of steel mills, to reduce phosphorous (P), sulfur (S) and the like in the steelmaking process to produce clean steel It is to provide a steelmaking slag ball preparation agent and a method of manufacturing the same that is easily recycled to.

The problem to be solved is achieved by the following solution means.

According to the first aspect of the present invention, the step of dropping the molten reduction slag tapping in the refining furnace during the steelmaking process through the tundish; Injecting high pressure air into the falling molten reducing slag from a nozzle to separate the molten reducing slag into microdroplets; And quenching the microdroplets at an appropriate particle size and dry-density condition by the injected high-pressure air and the ambient atmosphere. Provided is a method for manufacturing a reduced steel slag ball preparation comprising a.

According to a preferred embodiment of the present invention, the proper particle size of the sphere in the quenching step is 5.0mm or less, and the dry density is characterized in that 2.5 ~ 3.8g / cm ³ .

According to a preferred embodiment of the present invention, the falling steel reducing slag is characterized in that the drop in the state maintaining 1300 to 1900.

According to a preferred embodiment of the present invention, the nozzle is characterized in that for injecting air of 100 to 200 ℃.

According to another aspect of the present invention, there is provided a steelmaking reducing slag ball aid according to the first aspect, the main component by weight percent SiO ₂ 12wt% or less, CaO 35-66wt%, Al ₂ O ₃ 10-40wt% , MgO 10wt% or less, MnO 5wt% or less, T-Fe 10wt% or less, TiO ₂ 1wt% or less, and has a spherical degree of 0.9 to 1.0, particle diameter of 0.6 to 5.0mm Ball refills are provided.

Preferably, the steelmaking reducing slag ball preparation agent is preferably utilized in the production of clean steel by reducing components such as phosphorus (P) and sulfur (S) during the steelmaking process.

Steelmaking reducing slag ball preparation according to the present invention to replace the high-grade quicklime (CaO) and fluorspar (CaF ₂ ) as a substitute for the basic preparation to lower the manufacturing cost, recycling the reduced slag of waste is extremely limited use environmental pollution In addition, the high content of Al ₂ O _{3 in} the component promotes the reduction reaction of Fe oxide and promotes the dephosphorization and desulfurization to facilitate the removal of impurities, which can increase the recovery rate of the metal component, and the economic effect is large. It is made of granules and is easy to handle.

1 is a photograph of the steel reduction slag mentioned in the prior art.

Figure 2 is a photograph illustrating the steelmaking reducing slag ball preparation agent according to the present invention, (A) is a steelmaking reducing slag ball preparation agent having a particle size of 1.0mm or less, (B) is a steelmaking reducing slag ball of a particle size of 2.0mm or less, ( C) shows the reduced steel slag ball less than 5.0mm, and (d) shows the steel reducing slag ball preparation mixed with various particle sizes.

Figure 3 is a block diagram showing an embodiment of a method for producing a reduced steel slag ball preparation according to the present invention.

Hereinafter, the present invention will be described in detail.

Method for producing a steelmaking reducing slag ball preparation according to the present invention comprises the steps of 1) dropping the molten reduction slag tapping from the refining furnace during the steelmaking process through a tundish by the processing equipment described below, 2) the falling melt reduction Injecting high pressure air from the nozzle into the slag to separate the molten reducing slag into fine droplets, and 3) rapidly cooling the fine droplets to an appropriate particle size and dry density condition by the injected high pressure air and an ambient atmosphere. Characterized in consisting of steps.

Spherical reducing slag balls and some fibrous reducing slag are generated according to the conditions of the molten reduction slag in step 1) and the air spraying condition in step 2).

In addition, the steelmaking reduction slag ball preparation agent according to the present invention is produced by the steelmaking reduction slag ball production apparatus developed by the applicant including a tundish, injection device.

When the tundish is supplied while the molten reducing slag is melted in a predetermined amount during the secondary refining process, the molten steel reducing slag (hereinafter referred to as a "reduction slag") is intended to drop while flowing in a predetermined direction.

To this end, the tundish is formed to be inclined at a predetermined angle so that the reducing slag in the molten state supplied from the refinery is retained and discharged.

The injector scatters molten reducing slag falling from the tundish. That is, the injector is located below the tundish to inject the injection to the molten reducing slag falling from the tundish to cool and solidify.

By the structure as described above, the injector makes the reducing slag scattered by spraying the injection to the reducing slag in the molten state falling in the tundish to form a reducing slag ball.

Here, the injector comprises an air injector for injecting air to the reducing slag falling in the molten state to scatter the reducing slag. That is, the spraying device for spraying the sprayed to the molten reducing slag falling from the tundish is made of an air injector for injecting air to make the molten reducing slag scattered.

By the structure as described above, the molten reducing slag falling from the tundish is scattered by the high-pressure air injected, and the reducing slag falls in the form of a ball. In addition, the reducing slag in the molten state falling from the tundish by the air injected from the air injector is loaded in a required position after flying a predetermined distance.

At this time, the injection environment, such as pressure, flow rate and temperature of the air injected from the air injector can be variously changed according to the amount of reducing slag in the molten state falling in the tundish, the position and angle of the air injector It can be variously changed according to the injection conditions, such as the amount of the reducing slag or the production form of the reducing slag ball.

In one embodiment of the present invention, the injector is made of an air injector for injecting air, but the injector may be made of a gas injector for injecting gas. That is, the injector may be constituted by a gas injector for injecting and scattering gas into the reducing slag so as to cool and solidify the reducing slag in the molten state falling from the tundish.

At this time, the gas injected from the gas injector is preferably made of nitrogen or the like to easily scatter and cool the reducing slag in the molten state, but is not limited thereto.

Also in this embodiment, the injection conditions such as the pressure, flow rate and temperature of the gas injected from the gas injector, and the injection conditions such as the position and angle of the gas injector depend on the amount of reducing slag in the molten state falling in the tundish. It is variously variable according to.

On the other hand, the injection device may be made of a cooling water injection device for spraying the cooling water to the reducing slag to scatter the reducing slag. That is, the injector may be configured as a coolant injector that sprays cooling water onto the reducing slag falling from the tundish to the molten state to scatter and cool the solidified slag.

In this case, the spraying conditions such as the pressure, flow rate and temperature of the coolant sprayed from the coolant spray device and the position and angle of the coolant spray device vary depending on the amount of reducing slag in the molten state falling in the tundish. Is variable.

On the other hand, the lamina flow chamber that can control the scattering trajectory and cooling rate of the reducing slag scattered by adjusting the amount and speed of the injection, such as air, gas or cooling water injected from the injector is connected.

That is, a lamina flow chamber for controlling the scattering trajectory and cooling rate of the reducing slag is connected to the injector by adjusting the amount and speed of the sprayed material such as air, gas or cooling water sprayed from the injector to scatter the reducing slag. Is installed.

Here, the lamina flow chamber has an inlet and an outlet on one side and the other side, and is formed in a shape of increasing in diameter from the inlet and the outlet toward the center, and at least one passage partitioned therein for the injection therethrough. It is formed over.

In addition, a valve-type damper is provided at the center of each passage so as to be open / closeable in order to adjust the amount and speed of the injection, such as air, gas, or cooling water.

As described above, the valve-type damper is installed at the center of each passage of the lamina flow chamber and rotated and varied about its central axis to open / close each passage, thereby being supplied to the injector and reducing slag. By controlling the amount, speed and distribution of the injection sprayed to the various to control the scattering trajectory and cooling rate of the reducing slag.

On the other hand, the flow guide is provided on the front of the tundish to adjust the scattering direction, the fall distance and the scattering trajectory of the reducing slag scattered through the injection device. That is, a flow guide for adjusting the scattering direction, the fall distance and the scattering trajectory of the high temperature reducing slag scattered upward and left and right when scattering the reducing slag is provided through the injection device.

To this end, the flow guide has a coolant jacket for supplying coolant to the outside thereof, and a coolant spray nozzle for spraying coolant supplied through the coolant jacket is formed therein.

When the cooling water supplied from the cooling water jacket is sprayed to the cooling water injection nozzle by the structure as described above, the reducing slag scattered by the spray slag, the fall distance and the scattering trajectory are adjusted to contact the reducing slag on the surface of the flow guide. It is possible to prevent the injection flow of the injector due to surface wear and slag accumulation.

In an embodiment of the present invention, the coolant is supplied to the coolant jacket of the flow guide, and the supplied coolant is sprayed through the coolant spray nozzle to prevent surface wear and slag accumulation occurring in the flow guide. After supplying the cooled air or gas to the spray it may be made to prevent the surface wear and slag accumulation phenomenon generated in the flow guide.

In addition, a slope chute is provided between the injector and the conveying conveyor so that the reducing slag that is dropped through the injector and then dropped is provided on the front side of the injector and flows to the conveying conveyor for conveying the reducing slag. .

At this time, the slope chute is formed to be inclined at a predetermined angle so as to flow the reducing slag dropped after being scattered through the injector to the transport conveyor.

On the other hand, the link conveyor is provided at the front end of the slope chute in order to transfer the reducing slag that falls and accumulates at the front end of the slope chute to the slope chute does not reach the slope chute of the reducing slag that has been dropped through the spray device after falling. do.

In other words, the link conveyor in front of the slope chute in order to flow into the conveying conveyor by transporting the reducing slag dropped to the slope chute without falling to the slope chute, but falling to the slope chute to the slope chute after falling through the injector Is provided.

To this end, the link conveyor is a kind of chain conveyor having a high heat resistance in order to withstand the high temperature of the reduced reducing slag, and is made to be automatically processed by forcibly transferring the reducing slag to the slope chute.

After falling through the injector by the structure as described above, the falling slag, the drop slag dropped to the front side of the slope chute the link conveyor is transferred to the slope chute, the slope chute is reduced slag transferred through the link conveyor And the reducing slag that has previously fallen flows into the conveying conveyor.

On the other hand, there is provided an inlet cooling chute for forced cooling by injecting air or / and water to the reducing slag that is dropped through the injector. That is, while falling through the injector to fall, while reducing the slag, such as high temperature reducing slag to the appropriate granularity and dry density conditions to cool and solidify the reducing slag by spraying air or / and water for forced cooling An inlet cooling suit is provided.

To this end, the inlet cooling chute comprises an air jet and a coolant jet.

As described above, the reducing slag can be completely cooled by injecting air or / and water into the reducing slag ball falling after being scattered from the injector through the inlet cooling chute, and a transfer facility installed at the rear end such as a bucket elevator. Its service life and driving efficiency are improved.

In other words, before the high temperature reducing slag dropped through the injector and dropped onto the slope chute is transferred to the bucket elevator installed at the rear end, the air inlet and / or cooling water in the inlet cooling chute passes through the inlet cooling chute. It is rapidly cooled by air and / or cooling water in the spray section and transported to the bucket elevator to protect conveying equipment such as bucket elevators and subsequent belt conveyors and extend their life.

On the other hand, the reduced slag ball preparation manufacturing apparatus is provided with a waste heat recovery device to recover the high temperature heat generated from the reduced slag and reuse it. That is, in the case of spraying the injection in the injector to scatter the reducing slag falling from the tundish, the waste heat recovery device is installed above the direction in which the reducing slag is scattered to recover the high temperature heat generated from the reducing slag. After recovery, reuse it.

To this end, the waste heat recovery apparatus is provided as a closed circuit to continuously increase the temperature generated in the reducing slag to a specific temperature in order to increase the heat recovery rate in the hot air generated in the reducing slag and to circulate it in the closed circuit and to circulate the above temperature. When rising, hot air is supplied to the waste heat recovery apparatus, and the waste heat generated in the reducing slag is recycled and reused by repeating this process.

The waste heat recovery apparatus is installed above the reducing slag in the scattering direction to recover the waste heat generated from the reducing slag, but if the waste heat generated from the reducing slag is easy to recover, the waste heat recovery apparatus is installed close to the tundish. It is also possible to be installed above the refining furnace.

As described above, the high-temperature waste heat recovered by the waste heat recovery apparatus may be used for drying cakes, briquettes, or the like, or used in waste heat recovery boilers to produce electricity, and at the same time, for steam production or heating. Can be.

On the other hand, there is provided a monitoring device for determining the supply amount, the discharge amount and the entire process of the reduction of the slag in the molten state supplied to the tundish from the refining furnace.

To this end, the monitoring device is connected to the camera and the computer provided on one side of the tundish to monitor the tundish and the camera for monitoring and displaying the supply amount, discharge amount and overall process of the reducing slag is connected to the computer It consists of a configuration including a warning device that lights up a warning light or generates a warning sound when an error occurs.

According to the structure as described above, the supply amount and discharge amount tapping out of the refining furnace in real time by the camera is photographed in real time, the photographed supply amount and discharge amount are transferred to the computer, the processed data is processed and reduced slag Adjust the supply amount and discharge amount.

In addition, when an abnormality occurs in the supply of reducing slag from the refinery to the tundish, the computer lights a warning light or generates a warning sound and delivers it to the field worker.

The various data measured and calculated through the monitoring system is transmitted to the central management system, thereby automatically controlling the entire process.

When an error occurs, the warning device is configured to deliver an abnormal situation to a site worker by lighting a warning light or generating a warning sound.In case of an error, the warning device transmits an error message to a wireless device such as a mobile phone, a smartphone, a PDA, etc. of the worker. It is also possible to be configured to convey the above situation.

In addition, an emergency operation tundish for replacing the tundish and a tapping loader (Launder) connected to one side of the emergency operation tundish are provided to enable emergency operation when the tundish is broken. It is made possible. That is, when an emergency situation occurs, such as a failure of the steelmaking reduction slag ball preparation manufacturing apparatus according to the present invention is made to switch to the tapping loader direction through the emergency operation tundish so that emergency operation is possible.

At this time, the switch from the tundish to the emergency operation tundish is operated by a hydraulic or power motor, and the emergency operation tundish is moved in a horizontal rotation according to the position of the tapping loader, and when an emergency occurs Continuous operation is possible.

Hereinafter, the manufacturing process of the steelmaking reducing slag ball preparation according to the present invention will be described with reference to FIG.

First, a predetermined amount of reducing slag is tapped in a refining furnace, and the reduced slag in the molten state is supplied to the tundish (S10).

At this time, the reducing slag supplied from the refinery to the tundish is about 1300 to 1900 ℃ degree, the tundish is positioned at an angle inclined.

On the other hand, the reduction slag supply amount and discharge amount of the molten state tapping in the refining furnace in real time with a camera of the monitoring device, and after calculating the data according to the supplied supply amount and the discharge amount and calculates the supply amount and discharge amount of the reduced slag Adjust

As described above, the reducing slag which is tapping in the refinery is formed in a molten state at a high temperature, and is scattered to the front side of the tundish by an injector for spraying the injection for the lower side of the tundish (S20). ).

Here, the reducing slag scattered to the front side of the tundish is scattered in a constant trajectory and at the same time as the reduced slag ball.

At this time, the injector is made of an air injector or gas injector or a coolant injector is made to inject air or gas or coolant to the reducing slag in the molten state (S30).

On the other hand, when the injection of the injection to the reducing slag in the injection device is controlled by the amount and speed of the injection sprayed by the lamina flow chamber is injected from the injection device to control the scattering trajectory and cooling rate of the reducing slag. That is, by controlling the opening and closing of the damper of the lamina flow chamber according to the supply amount and the discharge amount of the reducing slag in the molten state tapping in the refinery, the amount and speed of the injection injected from the injector is adjusted.

To this end, the lamina flow chamber is connected to a monitoring device, and the scattering trajectory and cooling rate of the reducing slag are controlled by adjusting the amount and speed of injection of the injection device according to the real-time supply and discharge amount of the reducing slag calculated by the monitoring device. It is preferably made to adjust.

In addition, the reduced slag in the molten state scattered by the spray injected from the injector falls into the slope chute while the reduced slag ball shape is deformed.

Here, the reduced slag ball is guided by a flow guide installed on the front of the tundish, so that the silicon manganese slag does not fly up, down, left, right and irregularly, but forms a scattering direction and a scattering trajectory, while the chute chute To fall.

On the other hand, the high temperature heat generated in the reduced slag of the molten state scattered by the spray injected from the injector is recovered through the waste heat recovery apparatus is recycled.

The reduced slag that has been scattered and then dropped into the slope chute is ball-shaped and is transferred to the inlet cooling chute along the slope of the slope chute, and the reducing slag ball that does not reach the slope chute is automatically transferred back to the slope chute through the link conveyor. do.

The reduced slag ball is transferred to the inlet cooling chute along the inclined surface of the slope chute and cooled. At this time, the inlet cooling chute cools the reducing slag ball by spraying air or / and cooling water to the reducing slag ball through an air injection unit and a cooling water injection unit by an automated valve and a temperature sensor, and reduces it through a bucket elevator at a later stage. Feed the slag ball.

Then, the monitoring device monitors the supply amount, discharge amount and the entire process of the reducing slag supplied to the tundish from the refinery in real time, and when an abnormality occurs, the warning light is turned on or a warning sound is generated to notify the operator of the abnormal situation. Safety accidents on site can be prevented.

In addition, in the case of failure and emergency of the quenching steel reduction slag ball preparation manufacturing apparatus according to the present invention, the emergency operation is possible by switching the direction to the tapping loader through the emergency operation tundish, as well as continuous operation is possible.

Hereinafter, the conditions of the molten reduction slag and the air injection conditions will be described in detail.

[Conditions of Melting Reduction Slag]

Steelmaking reducing slag contains a large amount of CaO and Al ₂ O ₃ components, the viscosity of the molten slag is relatively low. Therefore, a ball-shaped reducing slag is easily generated depending on the temperature of the molten reducing slag in the step of separating the molten reducing slag into fine droplets by spraying high pressure air onto the falling molten reducing slag. Generally, the temperature of the molten reduced slag at the time of falling is 1300-1900 degreeC, and it is preferable to manufacture a reduced slag ball. At this time, if the temperature is less than 1300 ° C too high viscosity clogging occurs in the tundish, and if it exceeds 1900 ° C the physical properties of the reducing slag ball is reduced by oxidation.

* [Air injection condition]

The molten reducing slag falls from the slag port via tundish. Although the distance from the nozzle when the molten reduction slag is dropped and dropped vertically is not defined in the present invention, the farther the distance is, the lower the efficiency of transferring energy of air to the slag is, so that the tip of the nozzle and the falling slag do not touch. It is preferable to install an injection nozzle called an atomizer nozzle as close as possible, and it is preferable that the air injection height is also directed to the upper side as much as possible so that the state of the slag remains as molten as possible before the air injection.

In the case of nozzles for injecting air, it is generally desirable to obtain spherical particles by using a single-hole straight nozzle. However, in order to increase throughput, the cooling effect of air is enhanced by using a Laval jet nozzle. It is also possible to use a nozzle.

According to a preferred embodiment of the present invention, the nozzle is characterized in that for injecting air of 100 to 200 ℃. At this time, when temperature is less than 100 degreeC, a viscosity will become high too much and the quantity of fiber generation will increase, and when it exceeds 200 degreeC, economic efficiency will fall.

In addition, the linear velocity of air at the tip of the nozzle is preferably 50 to 90 m / s, more preferably 60 to 90 m / s, and in the case of a jet nozzle, in consideration of the degree of deceleration until reaching the slag from the nozzle Mach 1.5 to 3 can be used.

Hereinafter, the chemical and physical properties of the reduced slag ball preparation prepared by the production method of the present invention will be described.

The reducing slag ball aid is 12 wt% or less SiO ₂ , CaO 35 to 66 wt%, Al ₂ O ₃ 10 to 40 wt%, MgO 10 wt% or less, MnO 5 wt% or less, T-Fe 10 wt% or less, TiO ₂ It contains 1 wt% or less, and is spherical in shape, and has a sphericity of 0.9 to 1.0 and a particle diameter of 5.0 mm or less.

The sphericity of the reducing slag ball aid of the present invention is calculated by the following formula (1).

[Equation 1]

Sphericity = surface area of a sphere with a volume equal to the particle / surface area of the particle

According to [Equation 1], it can be seen that the perfect sphere has a sphericity of 1, and the closer the sphericity is to 1, the closer to the perfect sphere.

"Particle surface area" means the actual surface area of a particular particle.

By "surface area of a sphere having a volume equivalent to a particle" is meant the surface area of an imaginary sphere having a volume equivalent to a particular particle.

The sphericity of the reducing slag ball aid of the present invention was 0.9 to 1.0, and the particle diameter was 5.0 mm or less.

In addition, the steelmaking reducing slag ball preparation agent according to the present invention is introduced during the steelmaking process to debin the steelmaking slag and desulfurization by the following reaction formula.

[Equation 2]

Tallinn Scheme: 3 [Ca] + 2 [P] = (Ca ₃ P ₂ )

[Equation 3]

Desulfurization Scheme: 3 [S] + 3 (CaO) + 2 [Al] = 3 (CaS) + (Al ₂ O ₃ )

Hereinafter, the present invention will be described in detail with reference to embodiments of the present invention so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

(Example)

Processing Equipment

1) melting furnace

The molten furnace used Moly Heater as a heating element, the commercial temperature was 1700 ℃, the temperature increase rate was up to 3 ℃ / min. The heating space of the melting furnace was 300mm long, 300mm long, 230mm high.

2) Atomizing system

The atomizing system consists of tundish and air spray nozzles. The tundish is a device to fall while allowing the molten reduction slag to be tapping by a predetermined amount. The air injection nozzle is a device for injecting high pressure air to the falling molten reduction slag.

Experiment process

In order to produce molten reducing slag, the reducing slag was heated in a melting furnace over 3 hours. The temperature was maintained after raising the temperature to 1700 ° C. After confirming that the reducing slag was molten, the molten slag was dropped through the tundish while injecting air from the air spray nozzle at the bottom.

The nozzle used was a slit nozzle. The atomizing time was 1 minute 50 seconds in total.

Experiment result

As a result of atomizing, the atomizing performance rate (reducing slag ball) was 53-67% compared to the sample input amount, and in addition to reducing slag ball, some reducing slag fibers were also generated.

(Reduction slag ball physical property analysis result)

Physical properties analysis results of the reduced slag ball preparation prepared according to the embodiment is as follows.

As shown in Figure 1, the reduced slag ball preparation showed the form of balls and short fibers having a greenish color close to turquoise.

The content of each component of the reducing slag ball aid is shown in Table 1 below.

Table 1

Ingredient	SiO 2	CaO	Al 2 O 3	MgO	MnO	T-Fe	TiO 2
Mass percent (wt%)	12 or less	35-66	10-40	below 10	5 or less	below 10	1 or less

The dry density, unit volume weight (kg / L) and performance rate measured for each particle size of the reducing slag ball preparation are shown in Table 2 below.

TABLE 2

Particle size	0.15mm	0.30mm	0.60mm	1.25mm	2.50mm	Bulk
Dry density (g / cm 3 )	3.60	3.24	2.90	2.86	2.87	2.99
Unit weight (kg / L)	1.91	1.80	1.88	1.88	1.83	2.01
% Of performance	53	59	65	66	64	67

Reducing slag ball as described above is spherical than the general reducing slag and has a variety of sizes of about 5mm or less, and has a dense structure and high hardness than the existing slag. In addition, the unit volume weight is high, the absorption rate is low, and the performance rate is high compared with the hydrated slag.

In addition, the content of CaO and Al ₂ O _{3 in} the component is also high to promote the reduction reaction of the Fe oxide to increase the recovery of the metal component, it can be used to remove impurities in the metal slag by promoting dephosphorization and desulfurization during the reaction. Since the slag basicity affects the flowability and the slag fluidity promotes the reaction, the basicity of the slag is known to be a very important factor in the steel reaction. Therefore, the preparation of the quench reduction slag ball preparation is essential for environmental and economic factors. In addition, the steelmaking reduction slag ball preparation agent may be used as a building material, concrete aggregate, asphalt pavement aggregate, polymer concrete aggregate, water treatment media, cover material or anti-slip material in addition to the preparation agent.

While the invention has been illustrated and described in connection with particular embodiments as described above, it is common in the art that various modifications and variations can be made without departing from the spirit and scope of the invention as set forth in the appended claims. Anyone with knowledge will know it easily.

Claims (7)

1. Dropping the molten reduction slag from the refining furnace during the steelmaking process through a tundish;

   Injecting high pressure air into the falling molten reducing slag from a nozzle to separate the molten reducing slag into microdroplets; And

   Quenching the microdroplets to a suitable spherical particle size and dry density condition by the injected high-pressure air and ambient atmosphere; Including,

   The appropriate particle size in the quenching step is 5.0mm or less, and the dry density is 2.5 ~ 3.8g / cm³                  A method for producing a reduced steel slag ball aid.
2. The method of claim 1,

   Method for producing a reduced steel slag ball aid, characterized in that the nozzle injects air at 100 to 200 ℃.
3. The method of claim 1,

   The slag falling through the tundish is It has a temperature of 1300 ~ 1900 ℃ manufacturing method of steelmaking reducing slag ball aid.
4. Steelmaking reducing slag ball preparation prepared by the manufacturing method according to any one of claims 1 to 3.
5. The method of claim 4, wherein

   The steelmaking reduction slag ball preparation agent is a weight percent of SiO ₂ 12wt% or less, CaO 35 to 66wt%, Al ₂ O ₃ 10 to 40wt%, MgO 10wt% or less, MnO 5wt% or less, T-Fe 10wt% Or less, ₁ wt% or less of TiO ₂ .
6. The method of claim 4, wherein

   The steelmaking reducing slag ball aid is a steel reducing slag slag ball aid, characterized in that the spherical degree is 0.9 to 1.0, the particle diameter is 5mm or less.
7. The method of claim 4, wherein

   The steelmaking reduction slag ball preparation is a steelmaking reduction slag ball preparation, characterized in that it is also used as a building material, concrete aggregate, asphalt pavement aggregate, polymer concrete aggregate, water treatment media, cover material, anti-slip material or cement admixture in addition to the use of the formulation. My.

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