SU881032A1 - Method of processing blast furnace slag - Google Patents

Description

one

The invention relates to the processing of blast furnace slags for products of various fractions and can be used in the processing of ladle residues of blast furnace slag.

There is a method of processing blast furnace slag, including preliminary mechanical splitting of a jet of slag melt into particles with subsequent grinding and cooling of melt particles with a jet of gaseous energy carrier. The advantage of this method is the grinding of most of the melt to a particle size not higher than 10 mm, which after grinding can be used for fertilizing Cl} However, this method is not applicable in all cases. It is inefficient, is accompanied by rapid deterioration of the centrifuge and does not protect the atmosphere due to the large amount of gases, dust and fibers released into the environment. It is effective only on installations of small capacity, equipped with a system for controlling and neutralizing hazards.

There is also known a method for processing blast furnace slag, which consists of

slag crystallization in the tank with subsequent cooling of the ingot by immersion in water 21

This method has several disadvantages. Immersion of ingots with a temperature of 600-900 ° C in water causes intense vaporization, and the steam contains toxic sulfur compounds H ijS and SOi. When this happens, the environment is polluted, conditions deteriorate. the work of staff, accelerated wear (corrosion) of the equipment. In addition, after cooling in the water of an ingot, the degree of its crushing of 15 for thermal stresses is small, respectively, the small fraction of small (less than 5 mu fractions. At the same time, the costs of crushing and slag grinding increase.

A known method of processing blast furnace slag by feeding slag melt into a trench, air cooling for 20-30 minutes, cooling, with water to 50 bOS 25-35 minutes; A vacuum in the air before the metal is completely removed can also be carried out when the slag melt is fed into the trench and after the processing of the blast furnace slag 3. The disadvantages of this method are the abundant formation of vapor containing hydrogen sulfide and ferrous anhydride. This impairs the sanitary and hygienic working conditions, equipment service conditions, with a large percentage of slag fraction exceeding 70 mm and an increased metal content. The purpose of the invention is to improve the working and working conditions of the equipment, reducing the metal content and the fraction above 70 mm in the resulting product. The goal is achieved by the fact that according to the method of processing the mineral slag, mainly bucket residues by feeding it into a trench, cooling it in air for 1020 minutes, cooling it with water and separating the lumps of metal, water cooling is carried out at a flow rate of 0.3-0.8 tons of blast furnace slag 10 -30 min with simultaneous stirring of slag, after which, before the metal is separated, trash slag is fed into the neck and the entire slag mass is mixed for 10-20 min. Moreover, waste slag is fed into the trench in the amount of 10-50% of the total mass of slag. PRI me R. According to a known method, slag (ladle residues) is fed into the trench, cooled in air for 15 minutes, then water is supplied to the trench in the amount of 1.7 40 minutes. After the completion of slag watering, large magnetic metals are selected. According to the proposed method, the residuals are fed into the trench and cooled in air for 15 minutes, then to accelerate the cooling process, the slag is mixed under stirring (shoveling the grab edge on the ladle for 25 minutes while simultaneously supplying water for cooling in 0.5 quantity. After the completion of slag pouring, dump slag in the amount of 30% of the total weight of the material is fed into the trench and expose the entire slag massif to repeated mixing (shoveling) with a ladle of a magnetic clamshell crane for 15 minutes without POD4CH oh la) | (giving water. Then the metal is separated. From the material processed by the two described processes, samples weighing 50 kg each are taken. The fractional composition (0-1 mm, 0-70 mm, over 70 mm) is determined from the samples.) fractions 0-1 mm and 0-70 mm determine the content of metal inclusions. In addition, the neutralizing ability (according to the Alma method) is determined for the fraction 0-1 mm. In the process of slag irrigation with water, the concentration of most current, gas - hydrogen sulfide in the outgoing steam. The intensity of vaporization is also visually compared. Thus, according to a visual assessment, the intensity of vaporization in the proposed method is 2-3 times lower than in the known method. The average concentration of Nl5 in the outgoing steam according to the measurements is 300-500 in this method, and in the known 500gb 1000 mg / m In comparison with the known, the proposed method provides 2-3 times less vaporization and 4-6 times less total emission in atmosphere. This allows for improved sanitary and hygienic labor conditions and equipment operating conditions. The fractional composition of the slag treated in a trench in both ways is given in the table. As can be seen from the above data, the processing of cakes (bucket residues by the proposed method provides an increase in the fraction of 0-1 mm and 070 mm by reducing the fraction of fractions above 70 mm .. This favors the processing of slag for fertilizers and building materials. The content of metal inclusions in the slag by fraction m 0-1 mm and 070 mm are shown in Table 1. In slags processed by the proposed method, the content of metal inclusions is much lower. The decrease in the amount of metal in fertilizers and building materials improves their quality, and the investigator oh efficiency ispol'uet:. mations agriculturally and stroielstve neutralizing ability lacquer fraction 0-1 mm depends little processing method and m is an average of 80% Comparable figures of shlakovoo product fractions predstavley table.

slag fractional composition,; May %

Neutralizing ability,%

The content of metal inclusions,% by weight of slag

40

15

40

20

Articulation allows the slag to be averaged at various heats, it is fine to grind it, and in combination with water it is possible to carry out a rapid and even cooling of the slag over everything with minimum water consumption. This makes it possible to reduce the fraction of fractions above 70 mm, to reduce the total vaporization and the concentration of H, 5 in the outgoing steam. : Enter. in the trench of cold waste slag and its mixing (by shoveling) with the bulk of the slag in the trench is important. Dump slag has a small composition, which immediately dramatically increases the fraction of fractions below 70 mm. The waste slag of the 0-70 mm fraction contains 3-4 times less metal inclusions than coke residues; therefore, entering the waste slag into the trench drastically reduces the relative metal content in the slag (% metal inclusions by weight of slag). Reducing the content of metal inclusions improves the quality of slag products and facilitates the processing of slag from the trench into finished products, for example, grinding slag with a fraction of 0-5 mm into flour. Entering cold shallow waste slag and mixing it with the cake makes it possible to additionally reduce the temperature of the slag and tarpaulin in the trench without exposure to water, and reduce its consumption.

Distinctive parameters allow to optimize the process and strictly regulate water consumption.

Summary of the Invention 1. A method for treating blast-furnace slag, preferably ladle residues, by feeding it into a trench, cooling it in air for 10-20 minutes, cooling it with water and separating pieces of metal, which is different in order to improve working conditions

o and equipment operation, reducing the metal content and fraction above 70 mm. in the resulting product, cooling with water is carried out at a flow rate of 0.3-.0.8 m per ton of blast-furnace slag for 10-30 minutes

5 while stirring the slag, after which, before the metal is separated, the waste slag is fed into the trench and the entire slag mass is mixed for 10-20 minutes.

2. Method POP.1, characterized in that the waste slag is fed into the trench in an amount of 1050% of the total mass of slag.

Sources of information taken into account in the examination

five

1. Author's certificate. USSR 631504, cl. From 05.0 3/04, 1977.

2. Authors certificate of the USSR 267438, cl. From 04 To 23/04, 1967.

3.Romanenko A.G. Metallurgical

0 slags. M., Metallurgists, 1977,

with. 97-100.

Claims (2)

The claims “1. The method of processing blast furnace slag, mainly ladle residues by feeding it into a trench, cooling it in air for 10-20 minutes, cooling it with water and separating pieces of metal, characterized in that, in order to improve working conditions and operation of the equipment, decrease in metal content and fractions above 70 mm. in the resulting product, water cooling is carried out at a flow rate of 0.3-0.8 per ton of blast furnace slag for 10-30 minutes while slag is mixed, after which dump slag is fed into the trench and the entire slag mass is mixed for 10-20 minutes. 2. The method according to claim 1, characterized in that the waste slag is fed into the trench in an amount of 1050% of the total weight of the spar.