KR20000042048A - Coolant for electric furnace - Google Patents

Abstract

PURPOSE: A coolant is provided to wire a cooling material with a thin steel plate without a bonding material. CONSTITUTION: A coolant for an electric furnace uses dust and sludge as a cooling material. Herein, the dust is used in a collected state while the sludge is dried and crushed into a certain particle form. The dust and crushed sludge are mixed each or together and are covered on a thin steel plate. The thin steel plate is 0.3 to 1.2mm and is generated as a defective product in a thin steel plate production process so that it contributes to recycling. In addition, a waste thin steel plate is available even if it is oxidized. This is because the thin steel plate reacts like iron ore used as the existing coolant.

Description

Converter coolant

The present invention relates to a coolant to which the temperature control of molten steel is input during the converter refining process, and in detail, unlike the conventional briquette coolant cured from the raw material to the caking additive, the cooling material without the caking additive It is related with the coolant wired by the steel plate.

In the converter refining, pure oxygen is blown through the lance at the top of the converter to oxidize P, S, C, and Si, which are impurities in molten iron and scrap metal, and at the same time, various auxiliary materials, For example, quicklime, dolomite, fluorite, iron ore, sintered ore and dust briquettes are added to refine the molten iron. Iron ore, sintered ore, dust briquette, etc. are composed of metal iron (Metal Fe), magnetite (磁鐵鑛: Fe203), hematite (赤 鐵鑛: Fe304), etc. in the converter up to about 35Kg / Ton-Steel It is added and reduced by the carbon contained in the molten iron to become molten steel or exist as oxygen in the molten steel. During the converter refining, dust and sludge are generated about 12kg / Ton-Steel during the converter refining process by the high pressure refining of pure oxygen and the input of iron ore, sinter ore and dust briquettes.

These by-products were discarded in the early stages, but the technology of solidifying them into a certain form by using a binder material and recycling them as a coolant in the converter is being used. The coolant is put into the molten iron when it is necessary to lower the temperature of the converter molten iron to a certain temperature. Many kinds of coolant made of by-products as a caking additive are used, such as cold-bonded pellets and dust briquettes. .

However, the coolant developed and in use until now is hardened by curing the by-products to a certain shape by the binder, there is a restriction that the drying and curing in the air for a long time. In particular, such a coolant has a low Fe content due to the addition of the binder, the cooling capacity is reduced and the loss to dust by the crushing during handling or input process is a problem.

Therefore, an object of the present invention is to solve the problems of the waste recycling method so far to supply a stable converter coolant.

1 is an example of the manufacturing process of the converter coolant of the present invention

2 is an example of the coolant of the present invention;

Figure 2 (a) is the converter coolant of the wiring step

2 (b) is a plan view and a front view of the converter coolant sealed at both ends;

The converter coolant of the present invention for achieving the above object is that one or two mixed powders of steelmaking dust and steelmaking sludge dried and crushed are filled in a cylinder made of a steel sheet, and both ends of the cylinder are sealed. It is configured by.

Hereinafter, the present invention will be described in detail.

The coolant raw material of this invention uses the dust and sludge which generate | occur | produce in the steelmaking process similarly to the existing coolant. Table 1 below shows representative chemical compositions of sintered ores and by-products dust and sludge used in the steelmaking process.

division Chemical composition (% by weight) T.Fe FeO CaO SiO ₂ Al ₂ O ₃ P S Zn Primary dust collection 61.0 33.3 20.0 3.20 0.50 0.09 0.02 0.16 Secondary Dust Collection 58.9 39.5 11.6 1.90 0.30 0.08 0.11 0.50 Dust collection sludge 64.5 18.1 7.1 1.90 0.40 0.13 0.02 0.11 Sintered Ore 65.0 - 9.8 5.5 1.7 0.04 0.01 0

In the present invention, dust and sludge as shown in Table 1 is used as a raw material of the coolant. For this purpose, dust is used as it is, but the sludge is dried and crushed to a certain granularity. Crushing is crushed to 3mm or less, more preferably 1mm or less.

Sludge and dust crushed to a certain particle size, as shown in FIG. 1, are mixed with each other or with each other, and then wrapped in a steel sheet to seal. At this time, the thin steel sheet is 0.3-1.2mm, which is advantageous in terms of recycling if it is used as a defective product in the steel sheet manufacturing process of the steel mill. In addition, such a waste steel sheet can be used even if it is oxidized after being left outdoors for a long time, because it can act the same as iron ore conventionally used as a coolant.

The case of wiring the coolant of the present invention will be described with reference to FIGS. 1 and 2, for example. First, as shown in FIG. 1, the steelmaking dust and the dry crushed steelmaking sludge are wrapped in a thin steel sheet to be bent to combine both ends (long sides) in the longitudinal direction of the steel sheet, and then the cutting expected portion is compressed up and down, and the up and down compression portion is By cutting and bending and cutting the cut short sides, the outflow of the filled cooling raw material is prevented.

The coolant prepared in this way can be cut so that the length of the long side is 70-120mm, the length of the short side is 40-70mm. This is set in consideration of the processability of the wiring process together with the inputability when the coolant is automatically injected into the converter.

As described above, in the present invention, the sealing material is wired and sealed with a thin steel plate without a caking additive, so that the time required for processing is greatly reduced and the Fe component of the coolant itself is high, so that the cooling effect is large, and dust by crushing during the feeding process There is an effect of providing a coolant that is not concerned about generation.

Claims (2)

A converter coolant in which one or two mixed powders of steelmaking dust and steelmaking sludge dried and crushed are filled in a cylinder made of a steel sheet and both ends of the cylinder are sealed. The converter coolant according to claim 1, wherein the cylinder has a long diameter of 70-120 mm and a short diameter of 40-70 mm.