Research and Application of Converter Bottom Hot Replacement

Published Time:

2024-01-28

Since the beginning of 2020, a few steel companies have introduced a converter bottom blowing oxygen + powder injection smelting technology.

Research and Application of Hot Bottom Replacement for Converters

Since 2020, a few steel companies have introduced a converter bottom-blowing oxygen + powder smelting technology.
This technology can make the molten pool stirring intensity intense, oxygen flow evenly dispersed into the molten pool, the upper slag layer has less impact on the furnace reaction, and can achieve unexpected smelting effects through bottom injection of iron ore powder or a mixture of returned slag and lime powder, etc. However, the service life of the bottom refractory materials is reduced, requiring multiple hot replacements of the bottom refractory materials.
In 2020, Jinan Ludong Refractory Materials Co., Ltd. began to research on hot replacement refractory materials and processes for converter bottoms.
In early 2021, through simulating the converter bottom replacement conditions and environment, the design, procurement of an arc furnace for bottom hot replacement experiments, and the design, investigation, and procurement of construction facilities were carried out. Through technical exchanges with Japan's Shinagawa, the joint refractory materials for bottom replacement were introduced. After multiple experiments under different conditions, a converter bottom hot replacement process was developed: including shaped refractory materials for converter hot replacement, mixing and conveying equipment for pipeline conveying top-pressure joint refractory slurry, and on-site construction processes.

In October 2021, on-site tests and construction were carried out at an 80-ton top-and-bottom blown converter at Taiyuan Iron and Steel Plant in Shanxi Province, with good results and positive feedback from the steel plant. In November of the same year, successful application was achieved at a 260-ton oxygen blowing and powder spraying converter at Hegang Group Handao Steel Plant.
In 2022, further tests and construction were carried out at Taiyuan Iron and Steel Plant in Shanxi Province and Hegang Handao Steel Plant, with good results. Currently, this converter bottom hot replacement technology has been skillfully applied in the above two domestic steel plants.