Cooling solidification recycling method for high-temperature liquid-state slag in steelmaking furnace

Abstract

The invention discloses a cooling solidification recycling method for a high-temperature liquid-state slag in a steelmaking furnace. The method comprises the following steps of: remaining slag, namely performing slag remaining operation after tapping, wherein the slag remaining amount in a converter is 5 to 40t; adding a coolant into residual slag according to the content of end point carbon in the converter and the slag remaining amount after the tapping, wherein the coolant comprises 1 to 3.0t of lime, 0 to 3.0t of magnesium carbon ball and 0.2 to 3.0t of dolomite; splashing the slag, namely splashing the slag and jetting N2 by using a gun under the pressure of between 1.2 and 1.5MPa at the temperature of between 25 and 35 DEG C for 3 to 7min, wherein the flow is 30,000 to 50,000Nm<3> / h; after the slag splashing is finished, lifting the gun, shaking the furnace to observe a slag splashing effect that whether the slag is solidified or not, and adding scrap steel together with iron after the high-temperature liquid-state slag in the furnace is cooled and solidified; and otherwise, adding 0 to 3.0t of coolant into the converter, wherein the coolant is lime. In the method, a tapping and slag remaining process, a slag splashing and furnace protecting process and a coolant adding process are combined, and the high-temperature liquid-state slag is recycled; and the slag is simply and effectively recycled, so that a good steel slag reaction condition is provided for subsequent smelting of the converter.

Description

technical field [0001] The invention relates to the technical field of converter steelmaking in the metallurgical industry, in particular to a method for cooling, solidifying and recycling high-temperature liquid slag in a steelmaking furnace. Background technique [0002] In the 21st century, my country's iron and steel industry has developed rapidly, and the national steel output has increased year by year. In 2010, the national crude steel volume has reached 620 million tons, of which about 90% have to go through the converter steelmaking process, and the amount of slag produced by the converter alone reaches several Tens of millions of tons, the cumulative stockpiled slag not only occupies a large amount of land, but also causes environmental pollution. How to recycle converter slag is a major issue of general concern. [0003] After the converter is tapped, the temperature of the slag left in the furnace is as high as 1500°C. If this high-temperature liquid slag is direc...

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Problems solved by technology

[0003] After the converter is tapped, the temperature of the slag left in the furnace is as high as 1500°C. If this high-temperature liquid slag is directly used in the converter, it will easily explode during the process of adding scrap steel or iron

At present, the recovery and utilization of converter slag is mainly through cooling the poured converter slag first, and then adding it to the lime-based dephosphorization agent. This kind of solid synthetic agent containing converter slag is mixed with a large amount of active lime, which is easy to absorb. It is not conducive to storage and transportation. While wasting a lot of heat, it cannot make full use of the favorable characteristics of high-temperature converter slag

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