材料期刊网

通过对新一代洁净钢生产流程中主要元素选择性氧化还原的热力学分析, 并结合首钢京唐公司铁水“全三脱”生产洁净钢的技术实践, 研究了新一代洁净钢生产流程中S, P, C等主要元素的控制规律, 并对新一代洁净钢生产流程进行了理论解析, 提出了需要进一步解决的若干工艺问题. 研究表明: 采用CaO/CaF₂脱硫剂的KR法脱硫, 可使铁水中S含量稳定地降到0.0020%以下, 终点硫的控制主要取决于脱磷转炉中的回硫量, 减少废钢和渣料等辅助材料带入的S以及适当提高脱磷炉渣碱度是减少半钢回硫量的关键; 在较低温度 (1300-1350 ℃)和较高氧位条件下造碱度合适的渣, 是脱磷转炉实现脱磷保碳的关键, 对于冶炼普通低磷钢, 将脱磷炉半钢P控制在0.03%以下, 则可将脱碳转炉终点磷控制在0.006%以下, 而对于冶炼超低磷钢, 则需将半钢P含量控制在0.008%以下, 转炉终点磷可以降低至 0.0020%以下; 脱碳转炉少渣冶炼、降低铁耗以及高碳出钢是新流程降低洁净钢生产成本和提高钢液洁净度的重要技术特征.

Based on the thermodynamic analysis on the selective oxidation of the main elements in the new generation of clean steel production process, and the production practices of hot metal treatment in the new process of clean steel production accumulated by the Jing Tang Iron and Steel Corporation, the control of the main elements such as S, P, C, etal., were investigated, and the main characteristics of the new generation of clean steel production process were analyzed. We indicate that several production problems must be solved. The research results show that, by using KR desulphurization technology, the S content of hot metal can be steadily controlled to less than 0.0020%. The final S control of the new production process of clean steel depends mainly on the resulfurization content in the dephosphorization furnace. Increasing the slag basicity and reducing the content of S from scrap and slag forming materials can reduce the resulfurization of hot metal. The formation of proper slag basicity at relatively lower hot metal pretreatment temperature (1300-1350 ℃) and at relatively higher oxygen potential is the key to solving the problem of removing P at high C content. The P content in dephosphorization furnace, when producing common low P steel (P<0.006%), may be controlled at less than 0.03%, whereas the P content should be below 0.008% when producing ultra low P steel (P<0.002%). Less-slag smelting, lower Fe losing and high carbon tapping of decarburization furnace are the important technological characteristics of the new generation of clean steel production process.