JPS6148445A - Use of steel slag - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention has the property of expanding and collapsing after cooling, so after aging treatment, it is partially used for roadbed materials, etc., but most of it is disposed of in landfills. This is related to the current effective use of steelmaking slag.

Although there are various types of steelmaking slag, the present invention targets converter slag and electric furnace slag (reducing stage). .

Generally, steelmaking slag is 2CaO・5iOz, F・CaO
, FMgO, 2CaO-Fe, 0.3, 4CaO・Human J
a03-Fe, Ov, Fev04, Feyu04
, FeO, etc., so it has no latent hydraulic properties,
When blast furnace slag is slowly cooled, it becomes melilite (2CaO).
i, 0JSiO, ~2CaO・Mg04SiOa) and CaS, and when rapidly cooled, it becomes mainly glass,
It has latent hydraulic properties and is used as an admixture for blast furnace cement.

Currently, these steelmaking slags are collected in a slag ladle, and are heated to about 20 to 12
It is discharged after some time, but when the temperature reaches about 200 to 300℃, it expands and collapses when 2CaO/SiO transitions from β to γ, and because it contains F-CaO and F-MgO, it expands and collapses. Therefore, as mentioned above, most of it is sold in landfills.

The present invention relates to a method of eliminating the above-mentioned drawbacks and making effective use of it.
Make a water slag so that it is mainly α'~β-2CaO-SiOz or glass, or one part α~β-2CaO・5101 and glass.
For example, CaO, Ca(Of()a, NaOH, Na
, COJ, CaC1λ, etc.) and kneaded with water, it was found that it has hydraulic properties.

It has also been found that the greater the powderiness, the more rapidly it hardens.

Furthermore, even though it is called converter slag, due to its chemical composition, there is also slag that has a very low iron content, and electric furnace slag also has a method of producing both the oxidation and reduction phases (one slag method), which only contains iron. When it is slowly cooled, 2CaO・Fe2
O, +, 4CaO-J'a (ly 4e, 03 is a component produced by modification treatment, and the resultant water slag has more strength.

The chemical composition range is quite wide and the basicity is high. The high melting point may reduce the slag rate.

Furthermore, by adding silicate rocks and minerals, a to β-2
'CaO・Sin, from the main body 2CaO3iO, ~2Ca
If the modification is mainly made of O-Mg0.2SiO, the melting point, viscosity decrease, and water scale rate will improve, and the glass will become mainly glass. After drying, it will be crushed to form an alkali stimulant (e.g. CaO, Ca (OH)).
It has been discovered that when a small amount of sludge, cement, etc.) is added and kneaded with water, it has hydraulic properties, and silicate rocks, minerals, etc. are added to uniformize the development of sludge solidification strength. It is.

AR, OJ, and 5iOa alone may be used as additives, but since they have the disadvantage of high melting temperature and difficulty in causing reactions, it is recommended to add materials containing appropriate amounts of Sinyu, FaOa, Fe□01, etc. This promotes a lowering of the melting temperature and allows the reaction to occur sufficiently.

How to add additives 1. Pour into the smelting furnace from the beginning or during the smelting process.

2. After tapping into the smelting furnace, pour it into the furnace.

3. Pour into contact with the slag flow discharged from the smelting furnace. (Simultaneous input) 4. Inject at a distance from the falling position of the slag flow from the smelting furnace to the slag ladle.

5. Use as a substitute for slag in a slag pot.

6. Pour the slag into the slag pan so that it forms a sandwich with the slag.

? , 3.4, 5, 6. Insert the lance pipe, and add bubbling gas (0, N, or human IR).
) and diffuse it.

8. Slag heating furnace (electric furnace method, 01 gas fuel furnace method)
The molten slag and additives, including the partially hardened slag, are introduced into the molten slag and additives.

There are methods etc.

The present invention aims to provide a method for effectively utilizing steelmaking slag as described above, and the gist thereof is to add a material rich in alkali-soluble silica or alumina such as silica stone and/or silicate clay to molten steelmaking slag. This method of utilizing steelmaking slag is characterized in that a water cooling treatment is performed after adding and mixing an admixture and a stimulant consisting of sodium hydroxide and/or sodium carbonate.

Incidentally, it is even more effective to simultaneously knead granite, sandstone, slate, etc. as the modifying material.

Experiments conducted to confirm the effects of the method of the present invention and their effects will be shown below.

Table 1 shows the chemical analysis values and properties of the samples used in the experiment.

Table 1 *Since dusting occurs during the cooling process and destroys W1, 10 oz was used. Others were measured by autoclave treatment using the ASTM method.

*1 The disintegration rate (z) was 100X for steelmaking slag (A) and 35% for steelmaking slag (B).

After drying the above sample in a constant temperature dryer (maintained at 105-110℃) for more than 24 hours, 500 g
It was then melted again in a siliconite electric furnace (maintained at 1550°C), taken out of the furnace, cooled in water, and made a water slag.
After drying, it is crushed to about 200 mesh or less, and the stimulants are caustic soda and soda ash (commercially available products are used), and the admixtures are acid clay and silica stone (dry at constant temperature (regularly 105-110°C)).
This sample was mixed with sludge (mainly kaolinite, montmorillonite, and α-quartz) with a moisture content of 305z in a mortar bowl, and then placed in a soil test mold in three layers using a rammer. Packed separately (
Table 4 shows the results of determining the compressive strength after curing in a humid air for one month (according to JIS method). The chemical components and properties of the prototype water slag are shown in Table 2, and the chemical analysis values of the admixture added are shown in Table 3.

Table 2 Table 3 Table 4 As mentioned above, according to the method of the present invention, silicate rocks, minerals, etc. are added to steelmaking slag while it is in a molten state to cause a melt-diffusion reaction. The melting point and viscosity are lowered by the subsequent water slag treatment, and the resulting mineral becomes mainly glass, and the hardening of sludge etc. is stronger than that of the unadded water slag, and it is also different from the case where blast furnace water slag powder is used. In the same way, sludge, etc. can be hardened, and if its strength is large, it can be used to harden briquettes, etc., as well as ordinary cement and blast furnace cement. It should be noted that it can also be used as a binder for pellets.

Procedural amendment (Restraint 1, Indication of the case 1982 Patent Application No. 169603 2, Name of the invention Method of utilizing steelmaking slag 3, Relationship with the person making the amendment Patent applicant address 3-chome, Magaku, Kokura Kita-ku, Kitakyushu City No. 6-42 Name Representative of Japan Magnetic Mineral Sensing Co., Ltd. Original 1) Meijo 4, Agent Address 1-10-27 Hakata-eki Higashi, Hakata-ku, Fukuoka City (1) [Claims column] (2) Specification of the specification Contents of the amendment in "Detailed Description of the Invention Column" 6 of the document As shown in the attached sheet... (1) The "Claims Column" of the specification is amended as follows.

1. After water-cooling the molten steelmaking slag, an admixture consisting of an alkali-soluble silica- and alumina-rich substance such as silica stone and/or silicate clay, and a stimulant consisting of sodium hydroxide and/or sodium carbonate are added and mixed. 1. A method of utilizing steelmaking slag characterized by the following.

2. Treating molten steel slag with granite, sandstone,
A method for utilizing steelmaking slag, characterized in that an admixture consisting of an alkali-soluble silica- and alumina-rich material such as silica stone and/or silicate clay is then mixed with an stimulant consisting of sodium hydroxide and/or sodium carbonate. (2) - Line 14 on page 5 to line 1 on page 6 of the "Detailed Description of the Invention" section of the specification are amended as follows.

Claims (1)

[Claims] 1. Adding to molten steelmaking slag an admixture consisting of an alkali-soluble silica- and alumina-rich substance such as silica stone and/or silicate clay, and a stimulant consisting of sodium hydroxide and/or sodium carbonate. A method of utilizing steelmaking slag, which is characterized by subjecting it to water cooling treatment after mixing. 2. Molten steelmaking slag, an admixture consisting of an alkali-soluble silica- and alumina-rich material such as silica stone and/or silicate clay, and a stimulant consisting of sodium hydroxide and/or sodium carbonate, granite, sandstone, slate, etc. foundry waste sand,
A modification material consisting of at least one member selected from the group consisting of brick waste, coal ash, whitebait, weathered diorite, sand, karami, glass waste, desiliconization slag, scale, iron ore, iron sand, shale, blast furnace slag, and red mud. A method of utilizing steelmaking slag, which comprises adding and mixing and then subjecting it to water cooling treatment.