JPS6148476A - 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] Since the present invention allows expansion and disintegration after cooling,
After aging treatment, it is partially used as roadbed material, etc.
The project concerns the effective use of steelmaking slag, which is currently disposed of mostly in landfills.

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

Generally, steelmaking slag is 2CaO0SiOa, F, CaO
, F8MgO, 2CaO・Fe>03, 4C&O-person(
2Oz 4exOa, Fe)04, Fea0
3. Since it contains FeO, etc., it has no latent hydraulic properties, and when blast furnace slag is slowly cooled, it becomes melilite (2Ca0
4mu0? - Contains 5iOh~2CaQ-MgO-2SiOq (intermediate component) and CaS, becomes glass-based when rapidly cooled, has latent hydraulic properties, and is used in blast furnace cement admixtures, etc.

Currently, these steelmaking slags are collected in a slag ladle, and are heated to about 20 to 12
Although it is discharged after some time, when the temperature reaches about 200 to 300°C, it expands and collapses when 2CaO SiO transitions from β to γ, and because it contains FCaOlFMgo, it has 1 expansion and collapse property, so as mentioned above, Most of it is disposed of in landfills.

The present invention relates to a method for solving the above-mentioned drawbacks and effectively utilizing the problems.
It is crushed by an air flow so that α'~β-2CaO-5iOp is mainly composed of α'~β-2CaO. (referred to as feng shui sludge), which has hydraulic properties when dried, crushed and kneaded.

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

In addition, even though it is called converter slag, it contains iron in its chemical composition! Ka, Ka, 4. good,. , Process, Process 65. There is also a method (one slag method) in which the oxidation period and reduction period are produced together for uke and slag, which contains iron to the extent that it becomes 2CaO-
After modification of the components produced by Fe O, 4CaO and Human 04e O, the feng shui slag is stronger.

It has a fairly wide chemical composition range and has a high melting point due to its high basicity, which may reduce wind and water slag formation rates.

Furthermore, by adding silicate rocks and minerals, α′ to β−
2CaO-sio, from 2CaO-SiOa ~
When modified mainly to 2CaO-MgO・2SiO, the melting point,
The viscosity decreases, the wind and water slag formation rate improves, and the glass becomes mainly glass.
a (OH) Yu.

It was discovered that by adding a small amount of cement, etc.) and kneading it with water, it has hydraulic properties, and in order to equalize the development of sludge solidification strength, silicate rocks, minerals, etc. are added. .

Shoulderyo03 and SiOyu alone are fine as additives, but
Since the melting temperature is high and it is difficult for reactions to occur, it is difficult to cause reactions, so by adding materials containing appropriate amounts of SiO, hLos, Fe, etc., the melting temperature is lowered and the reaction occurs sufficiently. It is.

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

2. After tapping, pour into the smelting 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 4-inch wedge with the molten slag.

? , 3.4, 5, 6. Insert the lance pipe and add bubbling gas (Oa, Nz, or Ai).
r) and diffuse it.

8. Slab heating furnace (electric furnace method, 01 gas fuel furnace method)
- Charge molten slag and additives, including postalized slag.

There is a way.

The present invention aims to provide a method for effectively utilizing the above-mentioned steelmaking slag, and its gist is to add fly ash to molten steelmaking slag.

waxite, weathered basalt soil, fireclay, volcanic ash, weathered clay,
Materials with pozzolanic reactivity consisting of at least one member selected from the group of calcined clays and which can be added to cements to achieve hardening properties, as well as cement and cement clinker.
This is a method of utilizing steelmaking slag, which is characterized by adding and mixing a stimulant consisting of: In addition, granite and sandstone are used as modification materials.

It is even more effective to knead slate at the same time.

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 *Due to dusting and disintegration during the cooling process, 1
It was set to 00X. Others were measured by autoclave treatment using the ASTM method.

*] The disintegration rate (X) was 100X for Mi slag (A) and 35g for steel slag (B).

After drying the above sample in a constant temperature dryer (maintained at 105-110°C) for more than 24 hours, it was placed in an electro-fused magnesia crucible with 500
g, remelted in a siliconite electric furnace (maintained at 1550°C), taken out of the furnace, tilted the crucible, blew it out from the pressure wJ chamber air nozzle, and dropped it into a water tank to create a feng shui slag and dry it. After that, it is crushed to about 200 mesh or less, and cement and cement clinker are used as a stimulant.
and gypsum (commercially available product) and waxite etc. (dried at 105 to 110°C in a constant temperature dryer and then crushed to about 200 mesh or less) as an admixture, and this sample was heated to 30.5 g of moisture.
The sludge (mainly kaolinite, montmorillonite, α-quartz) was mixed in a mortar mixing pot, and packed in three layers with a rammer into a soil test mold (according to the JIS method) after being cured in a humid air for one month, and then the compressive strength was determined. The results of the investigation are shown in Table 4.

The chemical composition and properties of the prototype feng shui sludge are shown in Table 2, and the chemical composition of the additive admixture is shown in Table 3.

Table 2 Table 3 Table 4 As mentioned above, according to the method of the present invention, when silicate rocks, minerals, etc. are added in a molten state to cause a melt diffusion reaction, the melting point viscosity decreases. When slag is turned into water slag in water after being crushed by wind in a wind crushing device, the minerals produced change to mainly glass, and the hardening of sludge becomes stronger than that of slag with no additives. It is also possible to harden sludge, etc. in the same way as in the case, and the strength was rather strong.

In addition, it can also be used as a binder for briquettes and pellets, similar to blast furnace cement.

Procedural Neyama Sesho (Voluntary) September j1, 1980

Claims (1)

[Claims] 1. Pozzolanic reactivity consisting of at least one member selected from the group consisting of fly ash, waxite, weathered basalt soil, fireclay, volcanic ash, weathered clay, and calcined clay to molten steelmaking slag. A substance that is added to cement to achieve hardening properties, and a stimulant consisting of cement and cement clinker are added and mixed, and then crushed by an air flow and then dropped into water. How to use steelmaking slag. 2. Molten steelmaking slag is provided with porazone reactivity consisting of at least one member selected from the group consisting of fly ash, waxite, weathered basalt soil, fireclay, volcanic ash, weathered clay, and calcined clay to form cement. A stimulant consisting of cement and/or cement clinker, which is added to achieve the effect, granite, sandstone, slate, foundry waste sand, brick waste, coal ash, whitebait, weathered diorite, sand, karami, glass waste, After adding and mixing a modifier consisting of at least one selected from the group of desiliconization slag, scale, iron ore, iron sand, shale, blast furnace slag, and red mud, the mixture is crushed by an air flow and allowed to fall into water. A method of using steelmaking slag, which is characterized by subjecting it to mulling treatment.