A high-efficiency smelting process for producing low-phosphorus clean steel by converter

Abstract

The invention discloses a high-efficiency smelting process for producing low-phosphorus clean steel by a converter. After the slag of the previous furnace is splashed, all or part of the final slag is left in the furnace, and raw materials are added for smelting. Blowing stage: control the position and flow rate of the oxygen lance, start to add iron oxide balls and return ore after the lance is fired, then add lime and lightly burned dolomite, and gradually hoist the lance position after adding all of them, and dump the slag; the second time Control the position and flow rate of the oxygen lance, start to add lime after ignition, adjust the slag material in time, control the position of the oxygen lance and the amount of oxygen supply, finally turn down the furnace, lift the lance, and finally leave all the slag in the converter for slag solidification Phosphorus fixation is used for the smelting of the next heat. The invention adjusts the slag in time when smelting low-phosphorus clean steel by adding the converter, controls the position of the oxygen lance and the amount of oxygen supply, and the tapping condition at the end can meet C≥0.12 at the same time. %, P≤0.006% high cleanliness low phosphorus steel converter terminal control conditions.

Description

technical field [0001] The invention belongs to the field of metal material production, in particular to a high-efficiency smelting process for producing low-phosphorus clean steel by a converter. Background technique [0002] In recent years, with the increasing demand of users for low-phosphorus high-quality steel products, more and more steel types require lower content of impurity elements. How to smelt low-phosphorus clean steel at the lowest cost is the field of steelmaking. The focus of the research. At present, the major iron and steel enterprises in Japan and some domestic enterprises widely adopt the converter "duplex method" (LD-NRP method of JFE, SRP method of Sumitomo Metal, H furnace of Kobe Steel, BRP method of Baosteel) operation process, but the The process has high requirements on equipment; there is also an operation mode of continuous dephosphorization and decarburization blowing of molten iron on the same converter, similar to the traditional double sla...

AI Technical Summary

Problems solved by technology

[0003] However, the early slag removal rate of the current low-phosphorus steel smelting process of the converter is generally low or unstable; The control fluctuation of the machine is large; it is difficult to ensure the carbon content of the end point C (C≥0.12%) while obtaining a lower P content (≤0.006%) at the end point; Less consideration; pay attention to dephosphorization in the smelting process, but do not pay much attention to the phosphorus fixation technology at the end point; the oxygen consumption and cycle of smelting with less slag are generally high; the erosion of the furnace bottom and furnace lining or The instability problem caused by accumulation is more prominent