JP2005256051A - Briquette for steelmaking raw material and its producing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a briquette for steelmaking raw material and its producing method with which shot waste can effectively be reused. <P>SOLUTION: After dripping down solidifying auxiliary agent D into the shot waste S constituted of metal powder C containing iron powder and shot ball B, this shot waste S is compress-formed and this compress-formed shot waste S is dried. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a briquette for a steelmaking raw material and a method for producing the same, and more particularly to a technique for effectively using shot soot generated when shot blasting is performed on an iron-based metal.

  The shot soot generated when shot brass is applied to an iron-based metal generally contains about 75 to 95% by weight of iron-based metal powder and used shot balls (steel balls). For this reason, the said shot straw can become an effective resource as a steelmaking raw material. However, this shot soot is easy to ignite and scatter, and contains a lot of shot balls, so it is difficult to solidify by compression molding or the like. For this reason, it is inconvenient in handling such as transportation and storage, and reusing it is disadvantageous both in terms of technology and cost. Therefore, the actual situation is that the shot dredge is disposed as landfill as industrial waste.

However, such landfill disposal of shot dredging is not preferable from the viewpoint of effective use of resources. There are also problems of causing environmental degradation and high disposal costs.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a briquette for a steelmaking raw material and a method for producing the same, which can effectively reuse shot straw.

The briquette for steelmaking raw material of the present invention for achieving the above object is a dried briquette containing an iron-based metal, and a shot straw containing iron-based metal powder and a number of shot balls is used as a solidifying aid. It is characterized by being solidified.
Since the briquette for steelmaking raw material having such a structure is solidified into shot straw using a solidification auxiliary agent, it can exhibit an appropriate mechanical strength and is easy to handle such as transportation and storage. . Moreover, since it is a dry solid substance, even if it puts into a blast furnace as it is, there is no possibility that bumping will occur or it will rise and be discharged. In addition, since a large number of shot balls composed of 90% by weight or more of pure iron are included, the amount of reducing agent used during steelmaking can be reduced. Therefore, shot straw can be reused as a high-quality steelmaking raw material.

The shot balls are preferably bonded to each other via an iron-based metal powder impregnated with the solidification aid. As a result, it is possible to easily and firmly bond the shot balls, which are conventionally difficult to combine.
The steelmaking briquette preferably contains 0.5 to 5% by weight of the above-mentioned solidification aid, thereby ensuring the quality as a steelmaking raw material and easily and reliably making shot wrinkles by the compression molding. It can be solidified.
The solidification aid is preferably at least one selected from sodium silicate, colloidal silica, aluminum phosphate, and asphalt emulsion. Thereby, the shot wrinkle can be solidified easily and firmly.

Moreover, the manufacturing method of the briquette for the steelmaking raw material of this invention includes the step of adding the solidification aid to the shot trough containing the iron-based metal powder and the shot ball, and the shot trough to which the solidification aid is added. It includes a step of compression molding and a step of drying the compression-molded shot basket.
According to the briquette manufacturing method for a steelmaking raw material having the above-described configuration, the solidification aid added to the shot trough can be permeated over almost the entire shot trough by compression molding the shot trough. it can. For this reason, although a lot of shot balls are included, the shot wrinkle can be hardened to a desired strength by the compression molding.

The briquette manufacturing method may further include a step of impregnating the shot glaze with a solidification aid between the step of compressing the shot glaze and the step of drying the shot glaze. In this case, briquettes having higher mechanical strength can be obtained.
As the solidification aid, it is preferable to use at least one selected from sodium silicate, colloidal silica, aluminum phosphate, and asphalt emulsion. Thereby, a shot soot can be solidified more easily and firmly.

According to the briquette for a steelmaking raw material of the present invention, the shot straw can be reused as a high-quality steelmaking raw material, which is useful for environmental conservation and can reduce the disposal cost of the shot straw.
In addition, according to the method for producing briquettes for steelmaking raw materials of the present invention, the briquette for steelmaking raw materials can be easily and inexpensively produced because it can be solidified to a desired strength simply by compression molding the shot straw. Can do.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a process diagram showing a method for producing briquettes for steelmaking raw materials according to one embodiment of the present invention. In the manufacture of the briquette A, first, the shot basket S (see FIG. 1A) generated when shot brass is applied to the ferrous metal is conveyed to the shot basket S while being conveyed by the belt conveyor 1. The solidification aid D was added dropwise (see FIG. 1 (b)).
The shot basket S is composed of a large number of used shot balls B thinned to a predetermined particle size or less by a shot and iron-based metal powder C, and the metal powder includes iron oxide powder. 60 to 65% by weight is contained. Further, as the solidification aid D, a 100% sodium silicate solution is used.

  Next, the shot basket S to which the solidification auxiliary D is added is compression-molded by a press using the molding die 3 (see FIGS. 1C and 1D). By this compression molding, the solidification aid D added to the shot basket S penetrates over almost the entire shot basket S. Thereby, the solidification auxiliary D can be uniformly impregnated into the metal powder C and can be evenly adhered to the surface of the shot ball B.

Next, the slag S impregnated with the solidification aid D is cured (dried), for example, for about 2 days (see FIG. 1 (e)), thereby solidifying the solidification aid D to produce steel. Briquette A for raw material is obtained (see FIG. 1 (g)). In the curing, it may be rapidly cooled by spraying normal temperature or cooled air.
As described above, the dried porous briquette A can be obtained. The briquette A preferably contains 95 to 99.5% by weight of the shot soot S and 0.5 to 5.0% by weight of the solidification aid D, thereby ensuring the quality as a steelmaking raw material.粕 S can be solidified easily and firmly. That is, if the solidifying aid D is less than 0.5% by weight, the mechanical strength is weak and easily damaged during transportation and other handling, and if it exceeds 5% by weight, the content of iron-based metal is increased accordingly. However, the quality as a steelmaking raw material is reduced.

  Since the briquette A obtained as described above is a porous material obtained by solidifying the shot basket S, the contained moisture can be easily and reliably removed by curing. For this reason, even if it puts into a blast furnace as it is, there is no possibility that bumping will occur or it will rise and be discharged. Moreover, since the shot basket S is solidified using the solidification auxiliary D, it can exhibit an appropriate mechanical strength and is easy to handle such as transportation and storage. In particular, since the solidification aid D has permeated almost all of the shot basket S due to the compression molding, a large number of shot balls B in the shot basket S are converted into a metal powder C containing the solidification aid D. Can be coupled to each other. For this reason, the shot cage S can be firmly solidified. And since it has many shot balls B which contain 90 weight% or more of pure iron, the usage-amount of the reducing agent at the time of steelmaking can be decreased. Therefore, the shot rod S can be reused as a high-quality steelmaking raw material.

FIG. 2 is a process diagram showing another embodiment of the briquette manufacturing method according to the present invention. This embodiment differs from the embodiment shown in FIG. 1 in that the solidification aid is added to the shot basket S between the step of compressing and molding the shot basket S and the step of drying the shot mold S. This is a point in which a step of further impregnating D is added.
The impregnation of the solidification auxiliary D is performed, for example, by immersing the compression-molded shot basket S in the solidification auxiliary D injected into the tank 8 while being conveyed by the belt conveyor 7 (FIG. 2 ( d)). As the solidification aid D injected into the tank 8, a solution obtained by diluting sodium silicate with water is used, thereby ensuring good permeability of the solidification aid D to the shot mold S which has been compression molded. doing. According to this embodiment, the mechanical strength of the briquette A can be further increased.

In the embodiment shown in FIG. 1, as the solidification aid D, a solution obtained by diluting sodium silicate with water may be used. In this case, in the compression molding, the solidification aid D is shot. It can be more easily and effectively penetrated into the cocoon S.
In any of the embodiments, at least one selected from sodium silicate, colloidal silica, and aluminum phosphate can be used as the solidification aid D. And it can solidify firmly.

  As the shape of the briquette A, in addition to the columnar shape shown in FIG. 1, the peripheral portion has a round shape such as an egg shape, an almond shape, a rugby ball shape, and the wall thickness increases from the peripheral portion toward the central portion. May have a substantially pillow shape (see FIG. 3). By molding into such a shape, it is possible to obtain a briquette A that is not easily disintegrated strongly against a compressive load and that is difficult to cause partial breakage at corners or the like.

  In addition, the briquette A is mixed with shot dust S when fine dust (dust collection dust) generated during steelmaking by an electric furnace, a flat furnace, or the like, or when refining metals such as copper, lead, tin oxide, brass, etc. What solidified with the solidification adjuvant D may be used.

It is process drawing which shows the manufacturing method of the briquette for the steelmaking raw materials which concerns on one Embodiment of this invention. It is process drawing which shows other embodiment of the manufacturing method of a briquette. It is a partial missing perspective view of a briquette.

Explanation of symbols

A Briquette B Shot ball C Metal powder D Solidification aid S Shot gutter

Claims (7)

  A briquette for a steelmaking raw material, which is a dried briquette containing an iron-based metal, which is obtained by solidifying shot iron containing iron-based metal powder and a large number of shot balls with a solidification aid.   The briquette for a steelmaking raw material according to claim 1, wherein the shot balls are bonded to each other through an iron-based metal powder impregnated with the solidification auxiliary.   The briquette for steelmaking raw materials of Claim 1 which contains the said solidification adjuvant 0.5 to 5weight%.   The briquette for a steelmaking raw material according to claim 1, wherein the solidification auxiliary is at least one selected from sodium silicate, colloidal silica, aluminum phosphate, and asphalt emulsion. A step of adding a solidification aid to shot straw containing iron-based metal powder and shot balls;
A step of compression-molding shot glaze added with the solidification aid;
And a step of drying the compression-molded shot trough.   The manufacturing of briquettes for steelmaking raw materials according to claim 5, further comprising the step of impregnating the shot glaze with a solidification auxiliary agent between the step of compression molding the shot glaze and the step of drying the shot glaze. Method.   The method for producing briquettes for steelmaking raw materials according to claim 5, wherein at least one selected from sodium silicate, colloidal silica, aluminum phosphate and asphalt emulsion is used as the solidification aid.

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