JP2004269961A - Briquette to be charged into slag-forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a briquette to be charged into a slag-forming device, which can effectively recycle a spent alumina grindstone. <P>SOLUTION: This briquette comprises a porous and brittle compact Z produced by compression-molding a composition containing the following (a) and (b) and the reinforcing part K for reinforcing the brittle compact, wherein (a) is the pulverized powder of the spent alumina grindstone and (b) is a floc containing ground chips of an iron-based metal and a grinding fluid. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a briquette for feeding into a slag generating apparatus, which can effectively reuse a pulverized powder of an alumina grindstone obtained by pulverizing a used alumina (Al ₂ O ₃ ) grindstone.
[0002]
[Prior art]
In recent years, various technologies related to waste treatment and reuse of used products have been proposed for realizing a recycling-based society. For example, briquettes are produced by grinding iron-based metals such as bearing steel and carburized steel (hereinafter used as a concept including polishing, super-finishing polishing, lapping, etc.) and flocculent aggregates containing oil and moisture, which are generated by briquetting. There has been proposed a technique of converting the steelmaking raw material into a steelmaking raw material (see, for example, Patent Documents 1 and 2).
[0003]
[Patent Document 1]
JP-A-2002-129248 (page 2)
[Patent Document 2]
JP 2001-310259 A (page 2)
[0004]
[Problems to be solved by the invention]
The proposed technology has made it possible to make effective use of discarded iron-based metal chips, but many are still being discarded. For example, there is a used alumina grindstone. Alumina whetstones are attached to various grinding devices and used for polishing steel, etc.Alumina whetstones that have completed their role are usually collected by the manufacturer and then entrusted to a waste disposal company for landfill disposal. It is the present situation. For this reason, from the viewpoint of effective use of resources and consideration of the environment, development of a technique for recycling used alumina grinding wheels has been desired.
[0005]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a briquette for a slag generation device input that can effectively reuse a used alumina grindstone.
[0006]
[Means for Solving the Problems]
The present inventors have intensively studied to effectively reuse used alumina grindstones. In the process, equipment that generates slag, such as blast furnaces, focuses on the use of slag fluidity modifiers containing alumina as a main component and blast furnace sedatives. We examined whether or not it was possible. As a result, instead of simply using the crushed powder of the used alumina grindstone as a solid material having a predetermined size, the crushed material of the used alumina grindstone and the flocculent aggregate containing the grinding chips and the grinding fluid of the iron-based metal are used. By using a molding composition containing, if a brittle molded body obtained by compression molding is strengthened with a solidification aid or the like, instead of a conventional slag fluidity modifier or a blast furnace sedative, or They found that they could be used with them, and completed the present invention.
[0007]
That is, the briquette for feeding into a slag generator (hereinafter, also simply referred to as “briquette”) of the present invention is a porous brittle molded product obtained by compression-molding a molding composition containing the following (a) and (b): And a reinforced portion for reinforcing the brittle molded body.
(A) Pulverized powder of used alumina grinding stone.
(B) A flocculent agglomerate containing grinding chips and grinding fluid of an iron-based metal.
[0008]
According to the above configuration, a flocculent powder containing a grinding powder of an iron-based metal and a grinding fluid is used together with a crushed powder of a used alumina grindstone, and furthermore, since a reinforcing portion is formed, a predetermined strength and shape are obtained. Maintainability is ensured. In addition, since the powder contains pulverized powder obtained by pulverizing a used alumina grindstone, the slag has a good fluidity when used in various devices that generate slag. Therefore, a briquette in which the used alumina grindstone can be effectively reused is obtained.
Here, in the present invention, the `` slag generating device '' is a general term for various devices that generate slag such as a blast furnace, and all of the conventional slag fluidity modifiers and blast furnace sedatives that have been charged are used. Including equipment.
[0009]
In the briquette, it is preferable that the reinforcing portion is a reinforcing layer formed in a layer on at least one of the surface below and on the surface of the brittle molded body. By providing a layered reinforcing layer below or on the surface of a brittle molded body that may collapse in this way, even if a crack occurs in the brittle molded body due to impact during transportation, etc., it is prevented from collapsing beforehand Therefore, the shape maintaining property is further secured.
Here, in the present invention, “at least one of below and above the surface of the brittle molded body” refers to a case where a reinforcing layer is formed on the inner side (below the surface) with the surface of the brittle molded body as a boundary. The meaning includes a case where the reinforcing layer is formed on the outer side (on the surface) and a case where the reinforcing layer is formed on both the inner side (below the surface) and the outer side (on the surface).
[0010]
In the above briquette, it is preferable that the reinforcing portion contains a solidification aid. In this case, a reinforced portion (a reinforced layer) can be easily formed, and a briquette having high shape retention can be obtained.
In the above briquette, the solidification aid is preferably at least one selected from the group consisting of colloidal silica, sodium silicate, aluminum phosphate, and asphalt emulsion. In this case, a reinforced portion (reinforced layer) can be formed easily and reliably, and a briquette having higher shape retention can be obtained.
In the above briquette, the solidification aid is preferably pulp sludge. In this case, a reinforced portion (reinforced layer) can be formed easily and reliably, and a briquette having higher shape retention can be obtained. In addition, since pulp sludge, which is waste from paper mills and the like, is used, briquettes that are more effective in resource utilization and more environmentally friendly are obtained.
[0011]
In the above-mentioned briquette, the content ratio of the grinding chips of the iron-based metal is preferably set in a range of 1 to 60% by weight, particularly preferably in a range of 40 to 50% by weight. In this case, a large amount of pulverized powder of the alumina grindstone can be contained, and the predetermined shape is maintained.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view schematically showing a briquette according to an embodiment of the present invention, and FIG. 2 is a sectional view thereof. The briquette B according to the present embodiment has a columnar shape as a whole, and is composed of a porous brittle molded body Z and a reinforcing layer K as a reinforcing portion formed below the surface (inside).
[0013]
The brittle compact Z is a flocculent aggregate containing a crushed powder (a component) of a used alumina grindstone, a grinding swarf generated by grinding a ferrous metal, and a grinding fluid containing oil and moisture. (B component) and a molding composition which is compression-molded so as to have a columnar shape and a bulk density of 1.5 or more, preferably 1.5 to 3.0. The brittle molded body Z is configured as a porous brittle body having appropriate voids.
[0014]
Alumina stones used for grinding various kinds of steel and the like, which are to be disposed of are used. Then, such an alumina grindstone is pulverized with a hammer or the like to obtain pulverized powder. The content ratio of the pulverized powder of the alumina grindstone is preferably set in the range of 30 to 50% by weight with respect to the entire molding composition before compression molding, in consideration of the shape retention and the like.
[0015]
As the iron-based metal, a metal containing 0.2% by weight or more of carbon can be used. Such iron-based metal grinding chips have a large springback and are difficult to solidify. However, by applying compression molding, the influence of the springback during compression molding is eliminated to remove the grinding chips. Shearing can be performed effectively, and as a result, solidification becomes possible. As a typical example of the ground chips containing 0.2% by weight or more of carbon, ground chips of bearing steel can be given. The content ratio of the grinding chips of the iron-based metal is preferably set to 1 to 60% by weight, particularly preferably 40 to 50% by weight, based on the whole molding composition before compression molding. is there. If the amount of the grinding chips is small, the shape may not be maintained even when compression molding into, for example, a cylindrical shape. Conversely, if the amount of the grinding chips is large, the content ratio of the pulverized powder of the alumina grindstone decreases.
[0016]
The reinforcing layer K has a higher strength and a higher density than the inner side (brittle molded body Z) of the briquette B, and is formed in a layer shape. Such a reinforcing layer K can be formed, for example, by dipping in a liquid solidification aid or by applying (coating) a liquid solidification aid and then drying. As the solidification aid, colloidal silica, sodium silicate, aluminum phosphate, asphalt emulsion, and pulp sludge are preferably used. By using these, a strong briquette B can be obtained despite containing oil derived from the grinding fluid and pulverized powder of alumina grindstone. Here, pulp sludge contains woody pulp, clayey clay, moisture, etc., and is an industrial waste discharged from paper mills, etc., so briquettes that further consider the effective use of resources and the environment B can be provided. These solidification aids are used alone or in combination of two or more. The solidification aid is preferably used in an amount of 1 to 10% by weight, particularly preferably 5 to 10% by weight, based on the whole briquette B.
[0017]
The briquette B according to the present embodiment can be manufactured, for example, as follows. That is, first, as shown in FIG. 3, the flocculent aggregate M (see S <b> 1 in the figure) containing the grinding chips and the grinding fluid of the ferrous metal is transported by the belt conveyor 1 between the pair of rolls 2. Pressing and compressing by sandwiching (see S2 in the figure) preliminarily adjusts the content of water and oil, which are components of the grinding fluid contained in the flocculent M. However, there is a method of adjusting the water content and the oil content by simple air blowing or air compression. At this time, the flocculent aggregate M is preferably adjusted to have a water content not exceeding 50% by weight and an oil content not exceeding 10% by weight. , Storage and the like are easy to handle.
[0018]
On the other hand, the used alumina grindstone is crushed with a hammer or the like to obtain crushed powder A (see S3 in the figure). Then, the used alumina grinding stone pulverized powder A and the flocculent aggregate M in which the water and oil content are adjusted are mixed at a predetermined ratio to obtain a mixture C as a molding composition. (See S4 in the figure).
Subsequently, the obtained mixture C is compression-molded by a hydraulic press using the molding die 3 to obtain a brittle molded body Z (see S5 in the figure). At this time, the flocculent aggregate M is compressed so that the bulk specific gravity of the brittle molded body Z becomes 1.5 or more. By this compression molding, the spiral fiber-shaped ground chips contained in the flocculent aggregate M are sheared, and the ground powder A of the alumina grindstone enters the gaps between the sheared ground chips. Note that a mechanical pressure device using a ball screw or the like may be used.
[0019]
Next, as shown in FIG. 4, while the brittle molded body Z obtained is not conveyed slowly on the belt conveyor 4 so as not to collapse, the liquid solidification aid D poured into the tank 5 is placed in It is immersed (see S6 in the figure). Instead of the conveyor conveyance, the brittle molded body Z may be stored in a pallet or the like, and may be immersed in the liquid solidification aid D in a batch manner.
Thereafter, the brittle molded body Z impregnated with the solidification aid D (see S7 in the figure) is cured (dried) (see S8 in the figure) to obtain briquettes B (see S9 in the figure). Due to this curing, the excess solidification aid that has penetrated into the brittle molded body Z moves to the surface side and partially evaporates, and the remainder remains on the surface side of the brittle molded body Z, and the surface side becomes the inside. The reinforcing layer K having higher strength and higher density than the side is formed. Thus, the intended briquette B is obtained.
[0020]
The briquette B according to the present embodiment obtained in this manner uses a flocculent powder containing a grinding powder of an iron-based metal and a grinding fluid together with a crushed powder of a used alumina grindstone, and further forms a reinforced portion. Therefore, predetermined strength and shape maintainability are ensured. In addition, since it contains the pulverized powder (a component) of the used alumina grindstone, when it is put into a slag generation device such as a blast furnace, the fluidity of the slag becomes good. Also, since it can be used instead of or together with the conventional slag fluidity modifier or blast furnace sedative, the used alumina grinding stone can be effectively reused and the used alumina grinding stone is discarded. Since the amount of disposal can be reduced, it is environmentally friendly. Furthermore, since it is a dried solid matter having a predetermined size (for example, a cylindrical shape having a diameter of 40 to 70 mm and a height of 30 to 50 mm), even if it is put into a slag generator, it does not fly up and fly, and The occurrence of problems such as instability is also suppressed.
[0021]
In addition, as the shape of the briquette B according to the present embodiment, in addition to the cylindrical shape, the polygonal prism shape, and the like, an egg shape, an almond shape, a rugby ball shape, and the like, have a rounded peripheral portion, and have a central portion from the peripheral portion. It may have a substantially pillow shape in which the thickness gradually increases toward the portion. By being formed into such a shape, it is strong against a compressive load and hardly collapses, and partial breakage at corners or the like is hardly generated.
[0022]
The briquette of the present invention is not limited to the case where the reinforcing layer K is formed below the surface of the porous brittle molded body Z. For example, by applying (coating) a highly viscous solidifying auxiliary agent to the surface of the porous brittle molded product Z to reduce the amount of penetration into the brittle molded product Z, the surface of the brittle molded product Z can be reduced below and above the surface. A reinforcing layer may be formed. Further, the reinforcing layer may be formed on the surface of the brittle molded product Z by substantially eliminating the penetration into the brittle molded product Z by using a solidifying auxiliary agent having higher viscosity. Even if such a briquette is put into a slag generator and used, the fluidity of the slag can be improved. Therefore, effective use of resources and consideration for the environment are realized.
[0023]
Further, the briquette of the present invention may be produced, for example, by preliminarily including a solidification aid in the molding composition, compressing the molding composition, and then curing (drying) the composition. . In this case, the solidified solidification aid remaining in the brittle molded body is in an appropriately distributed state, and serves as a reinforcing portion for strengthening the brittle molded body. Such a briquette also secures a predetermined strength and shape maintainability similarly to the above. Further, the fluidity of the slag can be improved. Therefore, it is preferable from the viewpoint of effective use of resources and consideration of the environment.
[0024]
【The invention's effect】
As described above, according to the briquette of the present invention, a predetermined strength and shape maintainability are ensured, and when poured into a slag generation device, the fluidity of the slag can be improved. Is effectively reused. In addition, since what is disposed of is used, the environment is considered.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a briquette according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the briquette shown in FIG.
FIG. 3 is a schematic process diagram illustrating a process (up to compression molding) of manufacturing a briquette according to an embodiment of the present invention.
FIG. 4 is a schematic process diagram showing a process (after compression molding) for producing a briquette according to an embodiment of the present invention.
[Explanation of symbols]
B Briquette D Solidification aid K Strengthening layer (Strengthened part)
Z brittle compact

Claims (6)

It has a porous brittle molded product obtained by compression-molding a molding composition containing the following (a) and (b), and a reinforcing portion for reinforcing the brittle molded product. Briquette for slag generator.
(A) Pulverized powder of used alumina grinding stone.
(B) A flocculent agglomerate containing grinding chips and grinding fluid of an iron-based metal. The briquette according to claim 1, wherein the reinforcing portion is a reinforcing layer formed in a layer on at least one of a surface below and on the surface of the brittle molded body. The briquette according to claim 1 or 2, wherein the reinforcing portion contains a solidification aid. The briquette for feeding to a slag generator according to claim 3, wherein the solidification aid is at least one selected from the group consisting of colloidal silica, sodium silicate, aluminum phosphate and asphalt emulsion. 4. The briquette for slag generator input according to claim 3, wherein the solidification aid is pulp sludge. The briquette for feeding into a slag generator according to claim 1, wherein the content of the ground metal chips of the iron-based metal in the molding composition is set in a range of 1 to 60% by weight.

Images