Converter steelmaking process for recycling converter final slag

Abstract

The invention relates to a converter steelmaking process for recycling converter final slag, belonging to the technical field of converter steelmaking. The converter blowing process is divided into two steps including a dephosphorizing step and a decarbonising step; before the beginning of blowing in the dephosphorizing step, 0-70 kg / t of converter final slag in a cooled state is added firstly; then, bowing in the dephosphorizing step is carried out by adding iron and waste steel; slag having low FetO content is produced in the blowing process; deslagging is carried out after blowing; then, blowing in the decarbonising step is carried out; carbon catching and steel tapping are carried out after blowing in the decarbonising step; and converter final slag is remained in the converter and used for an underfired furnace to blow in the dephosphorizing step. The converter steelmaking process for recycling converter final slag disclosed by the invention has the advantages that the best use of converter slag is ensured to the most extent; and loss of steel materials is further reduced for smelting low-TFe dephosphorization slag.

Description

technical field [0001] The invention belongs to the technical field of converter steelmaking, and in particular provides a converter steelmaking process for recycling the final slag of the converter, which can recycle hot steel slag and cold steel slag, and greatly reduces the cost of converter steelmaking. Background technique [0002] Steel slag is one of the products of steelmaking. Generally, the amount of slag produced by converter smelting per ton of steel is more than 50kg-80kg, and the slag contains a lot of Fe t O and metal MFe; through the crushing, screening and magnetic separation of the final slag of the converter, a part of the slag and the Fe element in the metal state can be recycled, but most of the Fe element t O cannot be recycled, and this part of Fe element is wasted. [0003] Due to the technological progress and equipment upgrading of iron and steel enterprises, some steelmaking plants adopt double-connected converters to make steel. Such steel plants...

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Problems solved by technology

[0004] However, most of the manufacturers do not have the ability to carry out conventional smelting with the double-linked converter process. The method of steelmaking and steel slag recovery adopted by these manufacturers is usually to leave the slag at the end of the converter or completely, but the problem is that the slag can be safely mixed with iron and slag. The problem of enrichment of impurity elements in the furnace; steel slag left in the furnace can partially replace the slagging agent of the next furnace, but due to the continuous accumulation of impurity elements such as phosphorus and sulfur, the slag must be discharged, and the discharged steel slag still takes away the loss of steel materials Therefore, simple slag retention at the end cannot greatly reduce the consumption of iron and steel materials. What can be reduced is only a small amount of slag-making materials to reduce costs and a small amount of slag to reduce the consumption of iron and steel materials taken away.