Practice of Economical Smelting of Q355 Steel in Converter

doi:10.20057/j.1003-8620.2023-00203

Abstract

Abstract: The slag-making material addition system of Q355 steel was optimized， from the traditional "three-batch feeding" mode to the "eight-batch feeding" mode， and 100 kg steel slag modifier was added in the first and third batches respectively. At the same time， the oxygen blowing system of Q355 was changed from the traditional "constant flow， high-low-low lance position" control to "variable pressure， high-low-high-low lance position" control. Base above， a converter economical smelting process suitable for the actual production of Q355 steel was developed. The practice results show that compared with the original smelting process， the total oxygen supply time of the improved process is shortened by 1 min， the hit rate of phosphorus at the end point of smelting is 100%， the average value of phosphorus removal rate at the end point is increased by 4.24%， and the average value of lgL_p is increased by 0.35. Compared with the consumption of slagging materials in the original process， the average consumption of steel lime per ton in the improved process is 34.01 kg， a decrease of 8.73 kg， and the average consumption of total slag material per ton of steel is 43.95 kg， a decrease of 9.13 kg. In addition， the average iron and steel material consumption of the improved process is 1078.02 kg/ton steel， which is 0.60 kg/ton steel less than that of the original process. The economic smelting of Q355 steel converter is realized， the consumption of slagging material and steel material is reduced， and the production cost of Q355 steel smelting is effectively reduced.

Key words: Converter Steelmaking, Economic Smelting, Dephosphorization, Q355 Steel

摘要： 通过优化Q355钢造渣物料加入制度，由原来的“三批次加料”模式改为“八批次加料”模式，并在第一批次和第三批次各加入100 kg钢渣改质剂，同时，吹氧制度由传统的“恒流量、高-低-低枪位”控制优化为“变压强、高-低-高-低枪位”控制，开发了适合于Q355钢实际生产的经济性转炉冶炼工艺。实践结果表明，与原冶炼工艺相比，改进工艺总供氧时间缩短1 min，冶炼终点磷命中率达到100%，终点脱磷率平均值提高4.24%，lgL_p平均值提高0.35。与原工艺的造渣物料消耗相比，改进工艺吨钢石灰消耗平均值为34.01 kg，减少8.73 kg；吨钢总造渣料消耗平均值为43.95 kg，减少9.13 kg。此外，改进工艺吨钢冶炼钢铁料消耗平均值为1 078.02 kg，较原工艺减少0.60 kg。实现了Q355钢转炉经济性冶炼，减少了造渣物料和钢铁料的消耗，有效降低了Q355钢冶炼生产成本。

关键词: 转炉炼钢, 少渣冶炼, 脱磷, Q355钢

CLC Number:

TF713.3

Huang　Gaojian, Wei　Zehong, Song　Huan, Zhan　Dongping, Geng　Bin, Yang　Yongkun. Practice of Economical Smelting of Q355 Steel in Converter[J]. Special Steel, 2024, 45(1): 70-76.

黄高见, 韦泽洪, 宋欢, 战东平, 耿彬, 杨永坤. 经济性Q355钢转炉冶炼实践[J]. 特殊钢, 2024, 45(1): 70-76.

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