JPS62241849A - Use of de-p-s 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] <Industrial Application Field> The present invention compares the basicity generated in the de-S and de-P treatment steps, which are one of the preliminary treatments for hot metal that have become popular in recent years. This relates to the use of slag with high P and S content.

<Conventional technology> Until recently, hot metal was treated to remove Si and S, and the S was removed in a converter.

This was a steelmaking method that involved removing P and carbon. However, with the development of steelmaking technology, S was removed from the hot metal pretreatment process.

Now dephosphorization is carried out at the same time, and Cab is used as an additive.

, Fed, CaFz, FezOa, MnO, etc., can be used more efficiently, but the same slag can be used for P, S
If it is used as a sintering raw material with a high content, it will be reduced in the blast furnace and returned to the hot metal, so it is necessary to use a large amount of de-I)/S agent.

Also, this slug is 5in2. Ah03 is low (CaO
Since it has a relatively high basicity and a large amount of F-CaO, it expands and collapses, so it cannot be used as a roadbed material.When used as a cement raw material, it cannot be used in large quantities because it contains a lot of P and the setting of cement is delayed.

Therefore, at present, this type of P-S-free slag has little utility value and is mostly disposed of in landfills.

<Problems to be solved by the invention> The reason why the above-mentioned P-S slag is not utilized is that F.Ca.
If it absorbs a lot of moisture or water, it will expand and collapse, so it cannot be used for roadbed materials, etc.

In addition, since the content of P and S is high, when recycled as raw material for sintering or blast furnaces, P and S will increase in the hot metal.
As the use of deP-8 agents increases, the amount of slag generated also increases.

When used as a raw material for cement, the P content is high, which increases the concentration of P in the clinker and slows down the setting time, both of which are inconvenient, so most of it is disposed of in landfills.

The present invention eliminates the non-hydraulic property by changing the cooling conditions (water slag, wind crushing, slow cooling) and basicity (CaO/SiO2) of P-S-free slag, and P, S, CI, etc. The purpose is to provide a method for effectively using sludge as a hardening material, soil improvement material, etc., which does not cause any problem at most.

<Means for solving the problems> The present invention aims to impart latent hydraulic properties to de-ps slag and utilize it for a wide range of applications. DeP- in the molten state
The basicity (CaO/SiO
2) Add lime 9 limestone or carbide gas in an amount that should give a value of 5 to 9, place a lid on the lance pipe, and perform bubbling by blowing oxygen, air or nitrogen, or Using an electric furnace method, a lid is placed on a ladle, an electrode is inserted, electricity is applied to cause a melting reaction, and the slag and gypsum are then cooled, crushed, and subjected to magnetic separation to remove iron.
Mixed and ground with an irritant consisting of lime, sodium hydroxide, and calcium chloride.

Alternatively, it is a method of utilizing P-s-free slag, which is characterized in that it is crushed separately and then mixed and used as a sludge hardening agent, a soil conditioner, and a binder for pellets and briquettes.

Note that the cooling treatment for the molten p-s removal slag after reforming may be performed by slow cooling, water cooling, or air cooling, but in terms of cost, there is no need for water rig equipment, wind crushing equipment, drying equipment, or fuel costs. A slow cooling method is convenient.

Usually, it is finely pulverized so that the plain value is about 3100±50 m/g.

<Examples and Effects> The following will show experiments conducted to confirm the effects of the present invention and their results.

Chemical composition of the P-S slag used in this experiment.

The main minerals contained, the chemical compositions of granulated blast furnace slag and converter slag for comparison, and the main minerals contained are shown in Table 1 below.

The de-P-S slag mentioned above is slowly cooled slag obtained by injecting the P-8 agent into hot metal in a torpedo car, and cooling the molten slag discharged into a ladle by tilting it and discharging it into a field.

In addition, the molten slag before being tilted and discharged into the field as described above is scooped up with an iron ladle, cooled in water, and the water slag is then spread on the ground with thin iron plates and blown into the air using compressed air. (sometimes to the extent of turning black) to produce air-crushed slag.

Table 2 shows the main minerals contained in these water slags and ground slags.

Among slowly cooled slags, N has low basicity (CaO/SiO2)
Add lime to the non-magnetic material (5 mm or less) that has been subjected to crushing 1 and undergo magnetic separation, put it in an electrofused magnesia crucible, melt it again at 1400°C in a siliconite electric furnace, cool it in water, and turn it into a water slag. The crushed slag was then cooled in the air by blowing it with comb air.

Table 3 shows the chemical analysis values and main mineral content of the slag.

After drying, these slags are dried for 24 hours or more in a constant temperature dryer kept at 105 to 110°C, and then either ground or ground, or about 0.5 to 15% by weight of lime 9 gypsum or the like is added as a stimulant. Then, water was added to the mixture, which was finely pulverized to a Blaine value of about 3100±50 cor/g, or mixed with commercially available Portland cement, etc., according to the JIS mortar composition ratio. Examined. The results are shown in Table 4, and the results of the sludge solidification test are shown in Table 5.

Next, the agglomeration and granulation tests will be described.

Fine ore (particle size distribution is shown in Table 6) was prepared and examined as a binder for use as a raw material.

First, as a preliminary test, we conducted a concrete compression tester (Lo
ot) and molded using the tablet method (32φ
x35mm, molding pressure 1t/-1 added moisture 4.5%),
Table 7 shows the results of measuring the crushing strength over time.

For those with good composition, a briquette machine (50X50X32I
Table 8 shows the results of measuring the dough yield, crushing strength, etc.

When molding by the tablet method as shown in Table 6 and above, the tablet is removed and moved by hand when taken out of the mold, so it does not break at all, and if it is left to cure as it is, even if it is made of ordinary cement, it will have long-term strength and there will be no problem.

However, when making briquettes using a briquetting machine, about 35 to 40
Since the dough falls by 1.5 cm and is destroyed when transferred to a conveyor belt, the yield of the dough will be better if it can be strengthened in several minutes after kneading and before it is compressed. In other words, if only cement is used, it will be destroyed in this initial process, and even if bentonite is used as a thickener, it will have little effect, but if a crushed P-S slag that hardens in a few minutes is used, the effect will be greater. I understand.

Next, for the fine ore having the particle size distribution shown in Table 9,
Mix the prototype products (shown in Table 4) to the same proportions as shown in the table, and add about 10~15III while sprinkling with water.
Table 1O shows the granulation properties and drop strength when granulated to No. 11.

Table 9 Table 10 *l*2 *After 13 days, the number of times it is dropped from a height of 1 m onto a 10++ uw thick iron plate until it reaches approximately 172 *Crushing strength after 23 days From Table 10 above Powdered ore with poor plasticity cannot be granulated even if cement, cement and bentonite are mixed together, or blast furnace slag, lime and bentonite are mixed together. Of course, if a larger amount is mixed while ignoring the deterioration in quality, granulation can be achieved, but it cannot be used in practice.

However, when using the method of the present invention, in which lime or the like is added as a stimulant to P-S-free slag, granulation can be carried out well.

<Effects of the Invention> As described above, according to the method of the present invention, the product does not harden in its original state, contains a large amount of P-3, and may contain a considerable amount of NatO and CI, so its utility value is negligible. Therefore, after the metal is collected, it is disposed of in a landfill, but even if it is finely pulverized and mixed with sludge etc., materials with high basicity will harden, but materials with low basicity will not harden or will harden. However, only weak strength is produced.

Therefore, when the basicity is increased to about 5 or more, the strength decreases in the order of water slag, air crushed material, and slowly cooled material, but even slowly cooled materials may be finely pulverized by themselves, or gypsum 2 lime etc. may be added as a stimulant. When used after being finely pulverized, it can be used as a hardening agent in a shorter time compared to cement, and can be used as a sludge hardening agent. It can be effectively used as a binder for ores.

Patent applicant: Nippon Magnetic Mineral Sensing Co., Ltd. Procedural Authorization (Method) June 30, 1985 1, Indication of the case 1988 Patent Application No. 83368 2, Name of the invention Method of utilizing p-s slag removal 3 , Relationship with the case of the person making the amendment Patent applicant address: 3-I, Magakure, Kokura Kita-ku, Kitakyushu City] 6-42 No. 4, Date of amendment order: June 24, 1985, 5, Details of contents of amendment, page 2 Lines 7 and 8 [Add the phrase "3. Detailed description of the invention" between 1.

Claims (1)

[Claims] 1. DeP in a molten state containing partially solidified slag
．． The basicity (CaO/Si
After adding lime, limestone or carbide gas in an amount such that O_2) is 5 to 9, placing a lid on the lance pipe, and bubbling by blowing oxygen, air or nitrogen, or The slag, gypsum, lime, and sodium hydroxide are made by placing a lid on a ladle in an electric furnace, inserting an electrode, and applying electricity to cause a melting reaction, followed by cooling, crushing, and magnetic separation to remove iron. , sodium carbonate, and a stimulant consisting of at least one of calcium chloride are mixed and ground, or are ground separately and then mixed, and used as a sludge hardening agent, soil conditioner, and binder for pellets and briquettes. ．． How to use S slug. 2. The method for utilizing P-S-free slag according to claim 1, wherein the cooling treatment is slow cooling treatment (cooling in a ladle or cooling by flowing water). 3. The de-P. How to use S slug. 4. The method for removing P as set forth in claim 1, wherein the cooling treatment is an air crushing treatment (semi-quenching). How to use S slug.