【作者】 熊银成；

【导师】 文光华；

【作者基本信息】 重庆大学 ， 冶金工程， 2002， 硕士

【摘要】 本论文对重钢铁水进行了不同脱硫剂脱硫的对比实验室研究；在此基础上筛选出适合重钢条件的三种类型即CaO系、CaO-AD系复合脱硫剂和CaO-Mg系复合脱硫剂，对其进行了工业性试验，为大生产提供经济、实用的脱硫剂配方；同时对喷吹脱硫工艺参数进行了优化，建立脱硫粉剂消耗预测模型，并对脱硫后在铁包和转炉冶炼中的回硫问题及低硫钢的冶炼进行了研究；最后，对CaO+Mg石灰基混合喷吹进行了脱硫能力及综合消耗工业性扩大试验研究。主要结果为： (1)通过对CaO系、CaO-AD系和CaO-Mg系三种脱硫剂实验室实验和热力学分析，得出脱硫能力从大到小排序是：CaO-Mg系→CaO-AD系→CaO系。 (2)通过工业性试验后确立了适应重钢条件的脱硫剂类型是：中度脱硫剂为CaO石灰基；深度脱硫剂为CaO+Mg基。 (3)针对重钢炼钢厂脱硫现状存在的问题，在配方确定的基础上对脱硫工艺参数进行优化，取得了比较满意的冶金效果，处理成本下降了5.991元／吨铁，经济和社会效益明显。 (4)脱硫粉剂消耗数学模型的建立，采用石灰基脱硫，目标硫确定在0.006～0.010％内，消耗相对误差不超过5％，克服无模型前加料盲目的弊端，对提高脱硫命中率和降低生产成本发挥出重要作用。 (5)脱硫铁水在铁包内回硫的控制因素主要有三方面：喷枪结构、后搅工艺和铁水等待时间；通过正交实验法，得出影响重钢脱硫铁水在转炉内回硫的首要因素是废钢质量，再者是扒渣好坏，最后是石灰质量。保证最小回硫量的低硫钢生产方案是：扒渣好——低硫废钢——气烧低硫石灰。 (6)低硫钢冶炼实验证明：采用“石灰基铁水脱硫——转炉冶炼——吹氩——连铸”工艺路线，重钢炼钢厂已具备生产成品硫≤0.015％低硫钢的能力。 (7)CaO+Mg混合喷吹实验，处理结束[S]＜0.005％；相对石灰基础脱硫，粉剂消耗下降2kg／t，处理时间缩短3min，温降减少17℃以上。存在的不足是脱硫剂中Mg偏析严重，渣铁分离相对困难。更多还原

【Abstract】 In this paper,the compared experiment of desulphurization of hot metal of Chongqing Iron and Steel Co.(in short CQ),which is used by different desulphurizing agents,has been carried out in lab. On the base of the experiment,it is selected three type desulphurizing agents that fit the production condition of CQ have been carried out for industrial experiment,which are CaO-based,CaO-AD-based and CaO-Mg-based synthetic desulphurizing agent. It provided an economical and practical scheme of desulphurizing agent for product line. Meanwhile,the injection technologic parameters have been optimized,and a forecast model of consuming desulphurizing agent has been developed. The smelting resulfurization and smelting low-surphur steel in jar and converter after hot metal desulphurization have been researched. Finally,desulphurization capacity and entire consuming of Mg and CaO-based desulphurizing agent mixed insufflating have been on ampliative and industrial research. Then the conclusions can be drawn as following:(1)Through the experiments in lab and the thermodynamics analysis of the three types desulphurizing agents,which are CaO-based,CaO-AD-based and CaO-Mg-based desulphurizing agent,it can be gained that the array order of the desulphurization capacity from the stronger to the weaker is:CaO-Mg-based-CaO-AD-based - CaO-based.(2)The type of desulphurizing agent fit the production condition of CQ has been confirmed though the industrial experiment. Medium desulphurizing agent is CaO-based and deep desulphurizing agent is Mg plus CaO-based.(3)Aiming at the actual problem in desulfurization process of CQ,the desulphurization technologic parameters have been optimized on the basis of confirming the scheme. It is obtained approving metallurgical effect. Disposal cost has declined 5.991 yuan per ton steel,and the economic and social benefit is obvious.(4) With the foundation of consuming desulphurizing agent model,by using CaO -based desulphurizing agent,target sulfur is in the range of 0.006-0.010,and consuming fractional error has not been exceeded 5%. The unreasoning disadvantage of charging before having the model has been overcame. It is important for increasing the desulphurization rate and declining the production cost.(5) The control factors resulfurized of the desulphurizing hot metal in ladle have three important aspects:the structure of lance,the process after disturbing and the waiting time of hot metal. Through orthogonal experiment method,it can be obtained that the scrap quality is the chiefly factor to affect resulfurized of the desulphurizing hot metal in the converter at the steelworks in CQ:The second factor is decided by the slag removal which is better or not;The last factor is decided by lime quality. The best production scheme of low-sulfur steel,which can ensure lowest the resulfurization quantity,is:the high quality of slag removal,low-sulfur scrap,low-sulfur lime burnt by gas.(6)The low-sulfur steel experiments can prove that the steelworks in CQ has the capacity of producing the low-sulfur steel for the sulfur content less than 0.015% of the finished products by using the technical process of "desulfurization hot metal with CaO-based,converter smelting,argon-bubbling treatment and continuous casting. "(7)The experiment of insufflating Mg and CaO-based desulphurizing agent had been carried out. It can be obtained that the final point [S] could achieve 0.006-0.010%. Comparing the CaO-based desulphurizing agent,the consumed amount of powder reagent could be decreased 2 Kg per ton,the disposal time could be saved 3 minutes,and the reduced temperature could be decreased more than 17 C. The shortage of the experiment is Mg in the desulphurizing agent has great segregation,and it iscorrespondingly difficult for separating slag from hot metal.更多还原