WO2014077518A1 - Method for stabilizing dephosphorous slag produced in reductive dephosphorization process of stainless steel and iron alloy of carbon steel and manganese - Google Patents

Abstract

The objective of the present invention is to provide a method for stabilizing dephosphorous slag which is produced in the reductive dephosphorization process of stainless steel and iron alloy of carbon steel and manganese, wherein by re-melting the bdephosphorous slag at a high temperature and spraying high pressure air and inert gas onto the slag at a high speed in order to prepare the slag in the granular form of the ceramic state, calcium phosphate (Ca₃P₂), barium phosphate (Ba₃P₂), calcium carbide (CaC₂), and barium carbide (BaC_2,), which are created in the slag, can be immobilized in a molten state in the slag, and also, the slag can be treated harmlessly because it is not degraded in the air at room temperature. The present invention is technically characterized in that the method for stabilizing dephosphorous slag produced in a reductive dephosphorization process includes the steps of: melting dephosphorous slag produced in the reductive dephosphorization process of the stainless steel and iron alloy of carbon steel and manganese into a liquid phase by means of high temperature melting; spraying high pressure air and inert gas onto the molten dephosphorous slag that is in the liquid phase; rapidly cooling the dephosphorous slag by rapidly spraying high pressure air and inert gas; and particulating the rapidly cooled dephosphorous slag into a spheroidal form so as to have the granular form of the ceramic state.

Description

Stabilization Method of Tallinn Slag Produced in the Reduction Dephosphorization Process of Carbon Steel, Manganese Ferroalloy, and Stainless Steel

The present invention relates to a stabilization method of the Tallinn slag produced in the reduction Tallinn process, more specifically, calcium phosphate (Ca ₃ P ₂ ), calcium carbide (CaC ₂ ) components inevitably generated on the slag in the reduction refining method Stabilization method of the delineation slag produced in the reduction delineation process of carbon steel, manganese alloy iron and stainless steel which can be stably fixed on the slag without decomposing in the air at room temperature and can detoxify the slag generated in the reduction delineation process. It is about.

In general, there are reduction delineation methods for removing phosphorus (P) to be removed by reduction reaction of phosphorus (P) to be removed, and oxidative delineation method for removing phosphorus by oxidation reaction.

The reduction tallin method among the tallin processes of such steels has been studied by many researchers for a long time as a useful method in which delineation can be performed without oxidation loss of valuable elements such as manganese (Mn), chromium (Cr), and nickel (Ni) in molten metal.

However, in the above-described reduction dephosphorization method, phosphorus (P) component is present as phosphide such as calcium phosphate (Ca ₃ P ₂ ), barium phosphate (Ba ₃ P ₂ ), etc. Due to the low oxygen partial pressure during the reduction Tallinn process, about 1 to 5% by weight of carbide compounds such as calcium carbide (CaC ₂ ) and barium carbide (BaC ₂ ) are present in the slag.

As described above, phosphides such as calcium phosphate (Ca ₃ P ₂ ) and barium phosphate (Ba ₃ P ₂ ), and carbide compounds such as calcium carbide (CaC ₂ ) and barium carbide (BaC ₂ ) are brought into contact with moisture or groundwater in the air. The following reaction generates phosphine (PH ₃ ) and acetylene (C ₂ H ₂ ), which are harmful gases to the human body.

Ca ₃ P ₂ + 3 H ₂ O = 3CaO + 2PH ₃ (Gas)

Ba ₃ P ₂ + 3 H ₂ O = ₃ BaO + 2PH ₃ (Gas)

CaC ₂ + H ₂ O = CaO + C ₂ H ₂ (Gas)

BaC ₂ + H ₂ O = BaO + C ₂ H ₂ (Gas)

The reduction tallin method as described above has been studied as a useful method capable of tallin without loss of valuable elements such as manganese (Mn), chromium (Cr), and nickel (Ni), but the problem of treatment of slag after the delineation process is not solved. There was a problem that it is not used in the actual refining process.

On the other hand, when the reduction and de-lining process of molten steel, such as carbon steel (carbon steel), manganese (Mn) and chromium (Cr) containing stainless steel and stainless steel (Stainless steel) that require extremely low concentrations, quicklime (CaO ), Flux containing calcium carbide (CaC ₂ ) and fluorspar (CaF ₂ ) is used as the dephosphorizing agent.

In particular, the reduced dephosphorization method in which flux containing quicklime (CaO), calcium carbide (CaC ₂ ) and fluorspar (CaF ₂ ) is used as a dephosphorizing agent, is an expensive valuable element contained in molten steel, namely manganese (Mn) and silicon ( There is an advantage that a high tallin effect can be obtained without oxidation loss such as Si), aluminum (Al), and chromium (Cr).

However, calcium phosphate (Ca ₃ P ₂ ) and calcium carbide (CaC ₂ ) are inevitably generated in the slag after the reduction and delineation process, and when a lower cryogenic condition is required, the flux containing barium oxide (BaO) may be removed. There was a problem that barium phosphate (Ba ₃ P ₂ ) and barium carbide (BaC ₂ ) is produced by using as a dephosphorizing agent. That is, basic oxides such as quicklime (CaO) and barium oxide (BaO), which are the main components of slag after reduction and dephosphorization, are calcium phosphate (Ca ₃ P ₂ ), barium phosphate (Ba ₃ P ₂ ), calcium carbide (CaC ₂ ), It is present as barium carbide (BaC ₂ ).

As described above, since barium phosphate (Ba ₃ P ₂ ) and barium carbide (BaC ₂ ) components are thermodynamically unstable at room temperature, reacting with moisture at room temperature generates harmful gases to the human body and also easily differentiates. It is impossible to use as building materials and roadbed materials.

That is, when the slag containing the barium phosphate (Ba ₃ P ₂ ) and barium carbide (BaC ₂ ) component is embedded for a long time, the barium phosphate (Ba ₃ P ₂ ) and barium carbide (BaC ₂ ) component contained in the slag is moisture There is a problem in that the phosphine (PH ₃ ) gas and acetylene (C ₂ H ₂ ) gas harmful to the human body is generated in response to this, it is impossible to embed the slag.

These compounds react with water in the atmosphere to generate phosphine (PH ₃ ) gas and acetylene (C ₂ H ₂ ) gas, and because they are easily differentiated, air pollution, as well as ordinary steel slag, as a method of utilization as a resource There is no situation.

Here, the phosphine (PH ₃ ) gas is a colorless gas, and is treated as a representative toxic gas such that when it is inhaled for a long time, the central nerve may be paralyzed due to paralysis or cause respiratory arrest or asphyxiation.

In addition, carbide compounds such as calcium carbide (CaC ₂ ) and barium carbide (BaC ₂ ) react with moisture in the air to generate acetylene (C ₂ H ₂ ) gas, and slag easily forms powder when left for a long time with odor. Differentiate

For this reason, there was a problem that the slag after the reduction and de-lining process is difficult to develop for other purposes than the slag after the oxidative and de-lining process.

For this reason, the research and development to solve the problem of slag treatment after the reduction and de-lining process is required to usefully use as a refining method of special molten steel containing carbon steel, manganese and chromium.

On the other hand, the deoxidation method has been researched and developed in order to replace the reduction dephosphorization method which is not used in the actual refining process because the slag treatment problem is not solved after reduction and dephosphorization, and steelworks, ferroalloy, and special steel companies around the world use Carrying out the process.

In this case, when performing oxidative dephosphorization of molten steel such as carbon steel, manganese (Mn) and chromium (Cr) alloys and stainless steel that require extremely low concentrations, quicklime is generally used Flux containing (CaO) and fluorspar (CaF ₂ ) is used as the dephosphorizing agent.

However, when the delineation process is performed by applying the oxidative delineation method, as shown in the delineation process of general carbon steel, a large loss due to oxidation of valuable elements such as manganese (Mn) and aluminum (Al) contained in a small amount in the steel This happens. In other words, the loss of valuable elements in the delineation process by the oxidative delineation method is particularly prominent in the refining of high manganese steels and stainless steels containing a large amount of manganese (Mn), chromium (Cr) and nickel (Ni). Due to the delineation process for the delineation of special steel containing a large amount of manganese (Mn) and chromium (Cr) there was a problem that the oxidative delineation method is ineffective.

The present invention has been made to solve the problems described above, the object of the present invention is to re-melt Tallinn slag at high temperature, to produce a granular state on the ceramic by injecting a high pressure air and an inert gas to the slag at high speed As a result, calcium phosphate (Ca ₃ P ₂ ), barium phosphate (Ba ₃ P ₂ ), calcium carbide (CaC ₂ ) and barium carbide (BaC ₂ ) generated in slag can be stably fixed on the slag in a molten state. Rather, the present invention provides a method for stabilizing delineated slag generated in a reduction dephosphorization process of carbon steel, manganese alloy iron, and stainless steel, which is not decomposed in an air at room temperature, thereby making the slag harmless.

Another object of the present invention, by quenching molten Tallinn slag to produce a slag on the ceramic does not generate phosphine (PH ₃ ) gas and acetylene (C ₂ H ₂ ) gas even if the slag in contact with moisture at room temperature, Therefore, there is no change in the slag even if left in the air for a long time, and the stabilization method of the Tallinn slag generated in the reduction and desalination process of carbon steel, manganese alloy iron, and stainless steel, which can solve the environmental pollution problem that may occur in the treatment of slag. To provide.

In order to achieve the object as described above, the present invention, in the stabilization method of the Tallinn slag produced in the reduction Tallinn process, molten slag generated in the reduced Tallinn slag process of carbon steel, manganese alloy iron and stainless steel at a high temperature to the liquid phase Dissolving; Spraying high pressure Air and an inert gas on the Tallinn slag dissolved in the liquid phase at high speed; Quenching the Tallinn slag by high-speed injection of high pressure air and inert gas; And granulating the quenched Tallinn slag into a spherical shape so as to have a granular state of ceramic phase. Characterized in that comprises a.

Here, using the quicklime slag quicklime (CaO) and fluorspar (CaF ₂ ) to melt at a high temperature of 1400 ℃ to 1700 ℃ to be dissolved in the liquid phase.

Then, it is made to inject 1 to 6 atm of air (Air) to the Tallinn slag.

In addition, the inert gas is made of at least one of argon (Ar) and nitrogen (N ₂ ).

At this time, the spherical Tallinn slag stabilized by the stabilization method of Tallinn slag produced in the reduction Tallinn process is a road subgrade material, building material, building sand, concrete aggregate, asphalt pavement aggregate, polymer concrete aggregate, water treatment media It is used in the form of cover material, foundry sand or anti-slip material.

As described above, the present invention having the configuration as described above, calcium phosphate (Ca ₃ P ₂ ), barium phosphate (Ba ₃ P ₂ ), calcium carbide (CaC ₂ ) and barium carbide (BaC ₂ ) produced in slag Can be stably fixed and fixed on slag, so that calcium phosphate (Ca ₃ P ₂ ), barium phosphate (Ba ₃ P ₂ ), calcium carbide (CaC ₂ ) and barium carbide (BaC ₂ ) are not decomposed in the air at room temperature. In addition, even if the slag is in contact with moisture at room temperature, phosphine (PH ₃ ) gas and acetylene (C ₂ H ₂ ) gas is not generated, it can be effected to detoxify the slag.

In addition, the present invention, even if left in the air for a long time, there is no change on the slag can solve the environmental pollution problem that may occur in the treatment of slag, not only easy to recycle the harmless treated slag, but also waste resources It can be reused and reused for construction materials and industrial use such as road subgrade, building material, building sand, concrete aggregate, asphalt pavement aggregate, polymer concrete aggregate, water treatment media, cover material or anti-slip material Is high, and the reduction refining method can be applied to refining not only carbon steel but also manganese ferroalloy and stainless steel.

1 is a flow chart showing a stabilization method of the delineation slag generated in the reduction and delineation process of carbon steel and manganese alloy iron and stainless steel according to the present invention;

Figure 2 is a view showing the delineated slag particles after the reduction and delineation process of carbon steel according to the stabilization method of the delineation slag produced in the reduction and delineation process of carbon steel and manganese alloy iron and stainless steel according to the present invention,

3 is a view showing the delineated slag particles after the reduction and delineation process of manganese alloy iron according to the stabilization method of the delineation slag produced in the reduction and delineation process of carbon steel and manganese alloy iron and stainless steel according to the present invention,

Figure 4 is a delineated slag particles after reduction and delineation process of the stainless steel containing chromium (Cr) and nickel (Ni) according to the stabilization method of the delineation slag produced in the reduction and delineation process of carbon steel and manganese alloy iron and stainless steel according to the present invention. Drawing,

5 is a view showing a state after leaving for 12 months after the reduction and delineation process of carbon steel according to the stabilization method of the Tallinn slag produced in the reduction and delineation process of carbon steel and manganese alloy iron and stainless steel according to the present invention,

FIG. 6 is a view showing a state after being left for 12 months after reduction and dephosphorization of manganese alloy iron according to the stabilization method of Tallinn slag generated in a reduction and dephosphorization process of carbon steel and manganese alloy iron and stainless steel according to the present invention; FIG.

FIG. 7 is a view showing a state after being left for 12 months after a reduced delineation process of stainless steel according to a method for stabilizing delineation slag generated in a reduction delineation process of carbon steel, manganese alloy iron, and stainless steel according to the present invention; FIG.

8 is a view schematically showing a system according to a method for stabilizing slain produced in the reduction and desalination process of carbon steel, manganese alloy iron, and stainless steel according to the present invention;

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, the present embodiment is not intended to limit the scope of the present invention, but is presented by way of example only, and various modifications may be made without departing from the technical gist of the present invention.

1 is a flow chart illustrating a stabilization method of the delineation slag generated in the reduction and delineation process of carbon steel and manganese alloy iron and stainless steel according to the present invention, Figure 2 is a reduction and delineation process of carbon steel and manganese alloy iron and stainless steel according to the present invention Figure 4 is a view showing the dephosphorization slag particles after the reduction dephosphorization process of carbon steel according to the stabilization method of the resulting Tallinn slag, Figure 3 is a stabilization method of the delineation slag generated in the reduction dephosphorization process of carbon steel and manganese alloy iron and stainless steel according to the present invention. Figure 4 is a view showing the delineated slag particles after the reduction and de-lining process of the manganese alloy iron, Figure 4 is chromium (Cr) according to the stabilization method of the delineation slag generated in the reduction and delineation process of carbon steel and manganese alloy iron and stainless steel according to the present invention and Tallinn slain after reduction and desalination of stainless steel containing nickel (Ni) 5, 6, and 7 are graphs showing particles of carbon steel, manganese alloy iron, and stainless steel according to a stabilization method for delineation slag generated in a reduction and desalination process of carbon steel, manganese alloy iron, and stainless steel according to the present invention. FIG. 8 is a view showing a state after being left for 12 months after the process, and FIG. 8 is a view schematically illustrating a system according to a method for stabilizing slag generated in a reduction and desalination process of carbon steel, manganese alloy iron, and stainless steel according to the present invention.

As shown in FIG. 1 and FIG. 8, the stabilization method of the delineation slag produced | generated in the reduction dephosphorization process of carbon steel, manganese alloy iron, and stainless steel by this invention is for the detoxification process of the slag produced | generated in the reduction delineation process. The tundish 10 and the tundish 10 for supplying the slag port 2 having the slag in the hot molten state and the slag 3 falling from the slag port 2 in a predetermined direction and position are provided. It consists of a system (1) comprising an injector (30) for injecting an injection such as air or water with the injection nozzle 31 to the slag (3) falling through, the system (1) injector (30) The slag (3) is deformed into a slag ball (Ball: 5) after a predetermined distance by the spray injected from the injection nozzle 31 of the fall falls.

In the stabilization method of the Tallinn slag by the structure as described above, as shown in the flow chart of Figure 1, first, the Tallinn slag generated in the reduction and desalting process of carbon steel, manganese alloy iron and stainless steel is melted at high temperature to dissolve in a liquid phase (S10). ).

Here, using the quicklime slag, quicklime (CaO) and fluorspar (CaF ₂ ) to melt at a high temperature of 1400 ℃ to 1700 ℃ dissolved in a liquid phase.

Preferably, the Tallinn slag is melted in a liquid phase by melting at a high temperature of 1500 ℃ or more.

More preferably, the Tallinn slag is melted at a high temperature of 1600 ° C. or higher to dissolve in a liquid phase.

Then, high pressure air and inert gas are injected at high speed to the Tallinn slag melted at the high temperature and dissolved in the liquid phase (S20).

Thus, the high-temperature air and inert gas are sprayed at high speed to the Tallinn slag dissolved in the liquid phase at high temperature, thereby rapidly cooling the Tallinn slag (S30).

Here, it is made to inject 1 to 6 atm of air (Air) to the Tallinn slag.

At this time, the high-pressure air (Air) injected into the Tallinn slag is preferably made of 2 to 5 atm, but is not limited thereto.

On the other hand, the inert gas is at least one of argon (Ar) and nitrogen (N ₂ ). That is, argon (Ar) or nitrogen (N ₂ ) or argon (Ar) and nitrogen (N ₂ ) may be used as an inert gas injected with high-pressure air to the Tallinn slag.

In one embodiment of the present invention, the inert gas is composed of argon (Ar) and nitrogen (N ₂ ), but if it is easy to quench the Tallinn slag, it is also possible to be made to inject a variety of other gases to the Tallinn slag.

In addition, in one embodiment of the present invention is configured to inject a high-pressure air and inert gas at a high speed to the Tallinn slag to quench the Tallinn slag, if it is easy to quench the Tallinn slag and other various gases in the Tallinn slag Alternatively, the mixture gas may be injected at high speed.

As described above, high-pressure air and an inert gas are injected into the Tallinn slag to rapidly cool the Tallinn slag into a spherical shape so as to have a ceramic granule state (S40).

For this reason, the said Tallinn slag is manufactured from the ceramic Tall Tall slag ball (Ball) which has a magnitude of about 1-4 mm in diameter.

Figure 2 is a view showing the delineation slag particles after the reduction and delineation process of carbon steel according to the stabilization method of the delineation slag produced in the reduction and delineation process of carbon steel and manganese alloy iron and stainless steel according to the present invention, Figure 3 is a carbon steel according to the present invention Figure 4 is a view showing the de-lining slag particles after the reduction and de-lining process of manganese alloy iron according to the stabilization method of the de-lining slag produced in the reduction and de-lining process of the manganese alloy iron and stainless steel, Figure 4 is carbon steel and manganese alloy iron and stainless FIG. 5, 6, and 7 are views illustrating delineation slag particles after reduction delineation of stainless steel containing chromium (Cr) and nickel (Ni) according to the stabilization method of delineation slag generated in the reduction elimination process of steel. Tallinn slab produced during reduction and desalination of carbon steel, manganese alloy iron and stainless steel according to the present invention After the carbon steel, alloy steel and stainless steel, manganese Tallinn reduction process according to the stabilization method is a view showing the state after left to stand for 12 months.

The Tallinn slag ball manufactured as described above is used in road roadbeds, building materials, building sand, concrete aggregates, asphalt pavement aggregates, polymer concrete aggregates, water treatment media, cover materials or anti-slip materials.

In one embodiment of the present invention is a spherical Tallinn slag stabilized by the stabilization method of Tallinn slag generated in the reduction Tallinn process is a road subgrade material, building material, building sand, concrete aggregate, asphalt paving aggregate, polymer concrete Aggregate, water treatment media, cover materials or anti-slip materials are used alone, but may be used in combination with various other raw materials.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can 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.

[Experimental process]

Some of the spherical Tallinn slag stabilized by the Stabilization method of Tallinn slag produced in the reduction Tallinn process was left in the air, and the other part was stored by immersion in water.

The condition of the Tallinn slag ball left in the air regularly and the Tallinn slag ball submerged in water was checked.

As a result, there was no change in the shape of the Tallinn slag ball left in the air and the Tallinn slag immersed in water, and there was no gas generation and no odor.

Example 1

Ray of high-carbon iron (Fe) -75 to 95% manganese (Mn) using slag containing 20wt% quicklime (CaO) -60wt fluorite (CaF ₂ ) -20% silicon dioxide (SiO ₂ ) at about 1500 ℃ When the slag is excluded after the reduction and dephosphorization process in the field for 10 to 20 minutes, a system as shown in FIG. 8 is constructed to inject high-pressure air composed of 2 to 5 atmospheres, and at the same time, argon (Ar) and nitrogen ( Slag is quenched by injecting an inert gas such as N ₂ ) at high speed to produce spherical particles as shown in FIG. 2.

Example 2

Ray of high-carbon iron (Fe) -75 to 95% manganese (Mn) using slag containing 20wt% quicklime (CaO) -60wt fluorite (CaF ₂ ) -20% silicon dioxide (SiO ₂ ) at about 1600 ℃ When the slag is excluded after the reduction and dephosphorization process in the field for 10 to 20 minutes, a system as shown in FIG. 8 is constructed to inject high pressure air composed of 2 to 5 atmospheres, and at the same time, argon (Ar) and nitrogen ( Slag is quenched by injecting an inert gas such as N ₂ ) at high speed to produce spherical particles as shown in FIG. 2.

Table 1 division Phosphorus (P) concentration in slag after quenching Phosphorus (P) concentration in slag after 12 months of neglect Slag medium carbon concentration after quenching Carbon (C) concentration in slag after 12 months of standing Example 1 0.248 wt% 0.210 wt% 1.382 wt% 1.152 wt% Example 2 0.130 wt% 0.125 wt% 1.540 wt% 1.430 wt%

As shown in Table 1, after slag desulfurization of Examples 1 and 2, the slag was dissolved in a liquid state at a high temperature of 1500 ° C to 1600 ° C to be liquefied, and then high-pressure air and inert gas were injected at high speed. In this case, phosphine (PH ₃ ) gas and acetylene (C ₂ H ₂ ) gas are not generated, and decomposition degree of phosphide (Ca ₃ P ₂ , Ba ₃ P ₂ ) and carbide (CaC ₂ , BaC ₂ ) are remarkably Low.

In addition, the stabilized Tallinn slag after the reduction and dephosphorization process of Examples 1 and 2 is formed into spherical ceramic particles having a size of 2 to 3 mm, and phosphorus (P) in the Tallinn slag is formed of calcium (Ca) or barium (Ba) at a high temperature. Since it is dispersed and fixed on other oxides in a combined form, there is no space to react with moisture, so there is no fear of generating gas.

In addition, since the Tallinn slag on the ceramic is excellent in strength, it can be used for other purposes such as road subgrade materials and builders, and also has excellent color and high strength, so that it can be used as a substitute for construction sand.

While the invention has been shown and described in connection with particular embodiments, it will be apparent to those skilled 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 can easily know.

Claims (5)

In the stabilization method of the Tallinn slag produced in the reduced Tallinn process, Melting the delineation slag generated in the reduction delineation process of carbon steel and manganese alloy iron and stainless steel at high temperature to dissolve in a liquid phase (S10); Spraying a high pressure air and an inert gas at high speed on the Tallinn slag dissolved in the liquid phase (S20); Quenching the Tallinn slag by high-speed injection of the high pressure air and inert gas (S30); And Granulating the quenched Tallinn slag into a spherical shape so as to have a granular state of a ceramic (S40); Stabilization method of the delineation slag produced in the reduction and delineation process of carbon steel and manganese alloy iron and stainless steel comprising a. The method according to claim 1, Delineation produced in the reduction and delineation process of carbon steel, manganese alloy iron and stainless steel, characterized in that by using quicklime slag (CaO) and fluorspar (CaF ₂ ) to melt at a high temperature of 1400 ℃ to 1700 ℃ to dissolve in a liquid phase Method of stabilization of slag. The method according to claim 1, Stabilization method of the delineation slag generated in the reduction delineation process of carbon steel, manganese alloy iron and stainless steel, characterized in that the injection of 1 to 6 atm of air (Air) to the Tallinn slag. The method according to claim 1, The stabilization method of the delineation slag generated in the reduction delineation process of carbon steel, manganese alloy iron and stainless steel, characterized in that the inert gas is at least one of argon (Ar) and nitrogen (N ₂ ). The spherical Tallinn slag stabilized by the stabilization method of Tallinn slag produced in the reduction Tallinn process according to any one of claims 1 to 4 is used as road subgrade material, building material, building sand, concrete aggregate, asphalt pavement aggregate, polymer concrete. Tallinn slag, characterized in that used in the aggregate, water treatment media, covering soil, foundry sand or anti-slip material.

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