SU1009279A3 - Method for producing steel in converter - Google Patents

Abstract

A method of making steel from solid ferrous metal charges in a converter which is provided both with means for blowing oxygen onto the top of the melt surface and with means for injecting carbonaceous fuels beneath the surface of the melt, consists in producing in the converter from between 10% - 30% more molten steel than is required for a desired quantity of steel which is to be tapped from the converter and then, following such tapping of the desired steel quantity, the surplus amount of molten steel which has been produced in the converter is drained into another, separate vessel which acts as an auxiliary or holding ladle, and is subsequently re-introduced into the converter after the preheating of the next solid ferrous metal charge.

Description

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The invention relates to metallurgy, in particular to methods for the production of steel in converters of solid metal charge.

There is a known method of smelting steel in an oxygen converter from a solid metal charge, including heating the metal charge, filling it. in the converter, the supply of slag-forming, purging of the methyl-charge oxygen-fuel mixture to melt. Sludge and melt purging with oxygen 1 3. The disadvantage of the known method is that the metal charge is heated outside the converter. It requires availability; other than the converter unit, which makes it difficult to organize the process.

The known method of steelmaking in the converter, including heating. scrap by supplying oxygen and fuel from below 23.

However, this method takes a certain amount of time to waste scrap, which leads to a decrease in the productivity of the process as a whole.

The closest to the proposed technical essence and the achieved result is the method of steel production in the converter, which includes loading the solid metal charge, heating it by supplying oxygen and fuel from the bottom, blowing the carbon-containing powdery Materials and oxygen in the hydrocarbon-containing envelope from the bottom, as well as top with oxygen in the amount of 20-80% of the total oxygen consumption and steel production h.

The disadvantage of the method is that with a significant reduction in the amount of liquid iron (calculated on the weight of steel) and with the exclusive use of solid iron carriers, the melting time of the solid carrier is prolonged super-proportionally, as a result of which the melting time and the interval between the melts increase. In addition, the energy consumption during the melting phase fluctuates over a relatively wide range and on average increases slightly. Thus, with the exclusive use of solid iron carriers, the known method was not as economical as when using iron carriers in combination with a certain amount of liquid iron.

The purpose of the invention is to increase the productivity of the process.

The goal is achieved by the fact that according to the method of steel production, including

solid metal charge, its heating by supplying oxygen and fuel from below, purging the melt from below with carbon-containing powdered materials and oxygen in the hydrocarbon-containing envelope, as well as blowing oxygen from above in the amount of 20-80% of the total oxygen consumption and steel production, loading the solid metal charge into the amount is 10-30% more than the nominally produced amount of steel, the release of the nominal amount of steel is produced into the casting ladle, and the excess amount of steel is produced in the auxiliary put the ladle, carbonize it to a carbon concentration of 1-3% and pour it into the converter on the preheated charge, the quantity; which is equal to the nominal value of melting.

Carburizing of excess steel is carried out in a converter, after which the steel is discharged into an auxiliary ladle.

PRI me R. In the converter with a capacity of 60 tons, which has an operating temperatur., 54 tons of scrap are fed in and preheated for 8 minutes with diesel fuel and oxygen. In this case, nozzles for supplying diesel fuel and oxygen, located in the bottom of the converter, are used as burners. Diesel consumption

fuel is 600 liters, it is burned from 1320. After preheating the scrap from the transport ladle, 12 tons of liquid melt are fed to the converter. This melt is an excess of cobalt. The amount of steel of the previous heat, which is brought to a carbon content of 2.5%. Before loading, the scrap temperature is 1080 ° C, the temperature of the excess steel. In the ladle is 1350fc. To reduce the excess steel, the Si content is adjusted to 1.5% by adding FeSi to the ladle.

After adding liquid carburized and reduced excess steel to preheated scrap, only 8710 nm of oxygen and 6600 kg of coal are blown into the melt. At the same time, the oxygen supplied from above is also to astrally reach the off-gas. In addition, propane is blown in with the acidic prop. As propylene gas. Together with the oxygen supplied to the bottom of the converter, the melt blows 4200 kg of lime in the form of dust. Then, slag is removed from the oververter and additional blast is carried out. The total time to blow is sotavl. 34 min (without preheating the scrap for Vmin ..

3 1009279.

The resulting steel contains,%: C 0.1) Mh steel is produced in the transport

0.17; P 0.032; S 0.033) N 0.0024., Bucket. ,

The slag has an iron content of 14%. When repeating the process of the toea in this way, the duration of the float-change of excess amounts of vastack is 42 minutes.

§ a different bucket is released 11 minutes, 34 minutes.

48 tons of steel, the quality of which can be economical effect

set by adding alloying the proposed method is

items. After the release of 48 tons of high-capacity processing.

whether the remainder in the converter (12 tons) to-10 quantities of scrap in envelope. re in

sludge is added, silicon and iron deficiency conditions are added.

5 4S min (preload)

Claims (2)

1, METHOD OF PRODUCING STEEL IN A CONVERTER, including loading a solid metal charge, heating it by supplying oxygen and fuel from below, purging the melt from below with carbon-containing powder materials and oxygen in shell ^{1 of a} hydrocarbon-containing medium, and also purging from above with oxygen in an amount of 20-80% of the total oxygen consumption and steel production, characterized in that, in order to increase the process productivity, the loading of solid metal charge is carried out, in an amount of 10-30% more than the nominally smelted amount of one hundred or, a minimum amount of steel is produced in a casting ladle, and an excess amount of steel is discharged into an auxiliary ladle, carbonized to a carbon concentration of 1-3% and poured into a converter for a preheated metal charge, the amount of which is equal to the nominal smelting weight. “ 2. The method of pop. 1, characterized in that the carburization of the excess amount of steel * is performed in the converter, after which the steel is released into the auxiliary ladle. SU „„ 1009279