【作者】 时启龙；

【导师】 于学斌；

【作者基本信息】 武汉科技大学 ， 钢铁冶金， 2006， 硕士

【摘要】 本研究通过理论分析,对弱脱氧钢在RH中脱硫的机理进行了研究,得出了弱脱氧钢RH脱硫的限制性环节并不是热力学条件,而是动力学条件的观点,并被实验室实验和现场试验所验证。根据这一结论,进一步指出60%石灰-40%萤石型脱硫剂对弱脱氧钢脱硫效果差的根本原因是:该脱硫剂熔点高,熔化速度慢,降低真空室内钢水温度,从而严重的恶化了脱硫动力学条件。本研究针对弱脱氧钢在RH中脱硫的特点,提出了“三高,一低”的脱硫剂设计思路,即“高碱度,高CaO活度,高熔化速度,低熔化温度”。根据这一设计思路,研制出了一种的新型脱硫剂。新型脱硫剂满足了少氟或无氟的要求,具有良好的环保效果。新型脱硫剂具有较强的脱硫能力,脱硫效果明显优于现场使用的60%石灰-40%萤石型脱硫剂,且具有较快的脱硫速率,能够满足现场生产快节奏的要求。新型脱硫剂对浸入管的侵蚀轻微,对RH真空管路系统的侵蚀轻微,可大幅度降低RH操作成本,提高RH的产能。此外,新型脱硫剂还具有性能稳定,吸水性弱,以及对钢液碳含量影响小的特点。本研究还根据脱硫动力学的研究,以及新型脱硫剂的特点,开发出了新的操作工艺:(1)出钢结束后,按规定加入改质剂对钢包渣进行改质处理;(2)在RH进行脱硫时,脱硫剂的加入量可根据实际情况调整,不必每炉都过量加入,以节约成本。(3)脱硫剂加入速度应≤150kg/min;(4)脱硫处理温度应在1615℃以上。更多还原

【Abstract】 In this paper, the mechanism of desulphurization for feeble deoxygenize steel in RH vacuum treatment has been studied by the theoretical analysis. The conclusion which has been proved by the laboratory experiments and practice test, is that the desulphurization process of feeble deoxygenize steel is not controlled by the thermodynamic condition, but by the kinetic condition. According with this conclusion, the primary reason of inefficient desulphurization for feeble deoxidization steel, when the 60% lime and 40% fluorite desulphurizer is used, is that: the melting point of this desulphurizer is high, the melting speed is slow, and this desulphurizer decreases the steel temperature in vacuum chamber, all of them will serious deteriorate the kinetics condition.In this paper, the new design conception—“three-high and one-low”which involve“the high basicity, the high activity of CaO, the high melting speed, and the low melting temperature”—has been given, in allusion to the characteristic of desulphurization for feeble deoxygenize steel in RH vacuum treatment. According with the new design conception, a new kind of desulphurizer has been developed.The new desulphurizer has satisfied the requirement of less-fluoride or free-fluoride, and which is harmless to the environment. The new desulphurizer has the good desulphurization capability, and the desulphurization effect of it is better than the 60%lime-40%fluorite. Furthermore, the new desulphurizer which has the high desulphurization speed could satisfy the requirement of high production rhythm in practice.The new desulphurizer only has a slight corrosion on refractory of RH inserting tub, the corrosion of it on the vacuum pipeline system is slight too, and this will obviously reduce the operation cost of RH and increase the production capacity of RH. Furthermore, there are other characteristics of new desulphurizer, such as the stable capability, the weak hydroscopic property, and the little influence on the carbon content of liquid steel.According with the study of desulphurization dynamics and the characteristics of the new desulphurizer, the new operation process has been更多还原