New melting agent for steelmaking furnace slag

Abstract

The new cinder smelting agent for steelmaking is one kind of alkaline oxide comprising lime in 15-37 wt%, iron oxide ore powder 60-85 wt%, and has smelting point lower than 1200 deg.c. It may be applied to replace fluorite, and possesses the advantages of reduced environmental pollution, raised iron yield, decreased steelmaking cost, capacity of stabilizing steel quality, etc.

Description

Technical field: [0001] The invention belongs to the technical field of smelting electrofusion synthetic materials, and in particular relates to a novel slag-removing agent for steelmaking slag. Background technique; [0002] As far as the inventor knows, at present in smelting, making good slag is a very important link in the steelmaking process. The smelting slag contains a large amount of various oxides and a small amount of sulfide, and in some cases also contains a small amount of fluoride and carbide. For example, the physical and chemical properties and amount of slag in converter steelmaking slag are related to the removal speed and degree of impurities in steel, and are related to the absorption of non-metallic inclusions floating from metal, the size of splash and the absorption of metal. Yield, steelmaking slag is alkaline, and calcium oxide is the most abundant and alkaline oxide in the usual top-blown converter slag. Especially in top-blown converter smelting, t...

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Problems solved by technology

[0002] As far as the inventor knows, at present in smelting, making good slag is a very important link in the steelmaking process. The smelting slag contains a large amount of various oxides and a small amount of sulfide, and in some cases also contains a small amount of fluoride and carbide. For example, the physical and chemical properties and amount of slag in converter steelmaking slag are related to the removal speed and degree of impurities in steel, and are related to the absorption of non-metallic inclusions floating from metal, the size of splash and the absorption of metal. Yield, steelmaking slag is alkaline, and calcium oxide is the most abundant and alkaline oxide in the usual top-blown converter slag. Especially in top-blown converter smelting, the smelting time is very short, so it must be done Rapid slag formation, so that the slag has appropriate alkalinity, oxidation and fluidity as soon as possible, so that impurities such as phosphorus, sulfur, and silicon in the slag can be quickly eliminated to below the requirements specified by the steelmaking type, and slag overflow and splashing can be avoided. The current method is that fluorite is often added in smelting to promote the melting of slag. The main component of fluorite is calcium fluoride, which has a low melting point. Infiltrate the surface of lime (calcium oxide) to form a low melting point eutectic, or form CaO·CaF 2 · SiO2 2 , so that the melting point of calcium oxide is lowered, so it plays the role of rapid slag melting. However, if the amount of fluorite is too large, it will significantly reduce the life of the lining and cause environmental fluoride pollution. Steel slag without fluorite can also be used as phosphate fertilizer. You can't make phosphate fertilizer

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