转炉炼钢过程控制及造渣制度优化

转炉炼钢过程控制及造渣制度优化是转炉自动化控制的重要内容。本文介绍了国内目前常用的转炉冶炼控制方法,从自动化控制角度分类讨论了转炉冶炼过程中枪位、氧气流量和投料控制的特点,并结合转炉炼钢过程工艺控制的特点,对造渣制度的优化途径进行了论述。     

高酸性环境用超低硫管线钢冶炼工艺研究

介绍了在铁水预处理难以达到深度脱硫的条件下,以脱硫热力学和动力学理论为基础,对铁水预处理、转炉炼钢、炉外精炼等工序的工艺进行优化。通过对铁水预处理采用复合脱硫剂、转炉冶炼控制硫含量以及出钢脱硫、LF精炼双渣深度脱硫等各工序脱硫进行合理分配,达到了弥补铁水预处理未能深度脱硫、减小LF精炼炉脱硫负荷的目的,冶炼出w(S)≤0.001%、Ca/S≥2.0、夹杂物均不大于0.5级的高酸性环境用超低硫管线钢。     

100 t LF精炼脱硫生产实践

对影响钢水脱硫的热力学因素和动力学因素进行了分析讨论,并结合武钢一炼钢的实际和品种特点,从转炉冶炼控制,LF快速化渣、造渣,精炼温度,底吹氩流量,钢渣脱氧,合理选择精炼渣系以及优化炉渣成分等方面提出了LF精炼脱硫的技术措施。     

150 t转炉缩短冶炼周期的生产实践

转炉冶炼周期是控制炼钢整体生产效率的重要一环,缩短转炉冶炼周期,可以加快生产节奏、提高炼钢产量,同时,生产节奏的提高也可以减少过程热损失和耐材消耗,从而实现炼钢成本的降低。唐钢一钢轧厂为了缩短转炉冶炼周期,采取优化氧枪喷头设计、改进出钢口内径设计、调整溅渣物料、改善石灰质量、提高铁水扒渣效果、改善转炉底吹效果等多种措施,转炉冶炼周期由33.8 降低至23.89 min,降低了9.91 min,完成了我厂预设的转炉冶炼周期目标。     

基于钢铁大学网站转炉虚拟炼钢成本影响因素

基于钢铁大学网站虚拟炼钢模块,以建筑钢为例探讨了转炉虚拟炼钢成本的影响因素。虚拟炼钢模块依据最终的冶炼时间、出钢量、出钢温度、钢液成分以及渣成分进行判定,对判定合格后的模拟冶炼进行成本对比,以研究冶炼时间、出钢量、出钢温度、兑钢水量以及其他消耗等因素对冶炼成本的影响规律。经过数百次模拟冶炼,提取出冶炼成功并有效的174组数据进行分析,主要结论为:冶炼时间越短,成本越低;提高出钢量有利于降低成本;为了降低成本,应该尽量降低出钢温度。     

模式识别方法研究影响转炉炼钢脱磷的因素

利用模式识别方法中的偏最小二乘法对转炉炼钢的磷分配比及主要影响因素进行了分析 ,用二维分类图给出了优化趋势 ,结果符合一般脱磷理论和实际 ,可以作为冶炼的参考。     

转炉管坯钢生产过程中氮的行为

简介了攀钢集团成都钢铁有限责任公司采用80t转炉生产的管坯钢的主要钢种、工艺流程;分析研究了炼钢各工序钢液中氮的变化情况及不同冶炼条件对钢中氮含量的影响,提出了转炉炼钢各环节控制钢液增氮的技术措施。     

转炉低铁水比冶炼技术及生产实践

随着市场废钢供应量的大幅增加,降低铁水消耗增加废钢比例是转炉炼钢降低成本、提高效率的有效手段。文章根据钢铁冶金原理,以转炉物料平衡和热平衡计算为基础,分析了转炉降低铁水比的可行性和无外来补充热量条件下转炉的极限铁水比。理论计算和生产实践表明:在无外来补充热量的条件下,转炉的极限铁水比为82%~83%,对应铁水消耗为880~890 kg/t。通过入炉原料优化、冶炼过程工艺优化和底吹工艺参数调整,可以实现转炉低铁水比稳定生产,炼钢产量提高约10%,终点钢水质量稳定,炼钢成本明显降低。     

对影响转炉钢铁料消耗因素的分析与探讨

本文分析讨论了转炉冶炼钢铁料消耗的构成,通过改进冶炼工艺,实施少渣炼钢,能够有效减少转炉吹损,降低转炉冶炼的钢铁料消耗.     

转炉饱和蒸汽联合高炉富余煤气发电技术的应用

炼钢转炉冶炼过程中产生大量的饱和蒸汽,由于转炉冶炼的间歇性特点,导致所产蒸汽的压力及流量存在较大波动。由于转炉饱和蒸汽存在性能和流量不稳定的缺点,因此在发电项目的应用中存在一定的技术难度。本文分析了转炉饱和蒸汽的特性,并结合高炉富余煤气的情况,介绍了转炉饱和蒸汽联合高炉富余煤气发电技术在阳春新钢铁有限责任公司的应用情况。该技术符合企业节能减排、环境保护的要求,值得钢铁企业推广使用。     

Application of neural computing in basic oxygen steelmaking

The use of computer control in the basic oxygen steelmaking (BOS) process is essential to obtain accurate end-point temperature (EPT) and carbon control in liquid steel. The current computer model employed to execute this task is a procedural model that must be maintained by a person with considerable steelmaking knowledge. The requirement for an improved, maintenance reduced model is becoming increasingly important as expertise in this area is dwindling. The steelmaking process is highly complex and volatile. Artificial neural networks (ANNs) have been used to model this type of non-linear system. This paper describes an investigation into the use of ANNs to predict oxygen and coolant requirements during the end-blow period of the steelmaking process. During the end-blow period, a temperature measurement and sample are taken using a probe. These measurements are then used as inputs to the ANN model in order to predict how much oxygen to blow and how much coolant to add in order to achieve the desired end-point conditions in the steel at the end of the process. The software used to perform most of the modelling was the Clementine Data Mining System. This paper discusses the results from the ANN trials at Port Talbot BOS plant, which is part of the Corus Group.     

Grain Refinement of Ni-Cr-W Based Superalloy by Near Liquidus Casting

通过近液相线‘铸造’的方法得到了细晶组织。采用感应加热方式将熔体处理至近液相线温度附近指定温度,然后让熔体直接在坩埚中炉冷。在具有一定形核过冷度的坩埚中得到了细晶组织并探索了晶粒细化的机制。可以将过冷熔体的凝固过程分为2个阶段:非平衡凝固阶段;近平衡凝固阶段。与近平衡凝固阶段相比,球形晶粒扰动发展的临界半径Rc在非平衡凝固阶段急剧减小。在非平衡凝固阶段,晶粒更倾向于以枝晶方式长大,晶粒的增殖通过枝晶的熔断产生并且最终的晶粒密度由该过程决定。在近平衡凝固阶段Rc急剧增大。Rc的增大与晶粒增殖阶段所确定大的核心密度导致凝固在球形晶粒扰动发展之前终止。因此,最终得到粒状晶粒形态。     

基于RBF神经网络的转炉炼钢终点预报

转炉炼钢终点温度和成分是转炉炼钢的控制目标, 它与吹氧量、铁水加入量等多个变量之间存在着严重的非线性关系, 且无法在线连续测量。作者提出了基于ＲＢＦ 神经网络的转炉炼钢终点温度及碳含量预报模型, 并结合某钢铁企业一座１８０ｔ 转炉的实际数据进行模型验证研究。结果表明, 该方法收敛速度快, 预报精度高。     

Carbon Dioxide Sequestration via Steelmaking Slag Carbonation in Alkali Solutions: Experimental Investigation and Process Evaluation

Carbon dioxide mineral sequestration with steelmaking slag is a promising method for reducing carbon dioxide in a largescale setting. Existing calcium oxide or calcium hydroxide in steelmaking slag can be easily leached by water, and the formed calcium carbonate can be easily wrapped on the surface of unreacted steelmaking slag particles. Thus, further increase in the carbonation reaction rate can be prevented. Enhanced carbon dioxide mineral sequestration with steelmaking slag in dilute alkali solution was analysed in this study through experiments and process evaluation. Operating conditions, namely alkali concentration, reaction temperature and time, and liquid-to-solid ratio, were initially investigated.Then, the material and energy balance of the entire process was calculated, and the net carbon dioxide sequestration efficiency at different reaction times was evaluated. Results showed that dilute alkali solution participated in slowing down the leaching of active calcium in the steelmaking slag and in significantly improving carbonation conversion rate. The highest carbonation conversion rate of approximately 50% can be obtained at the optimal conditions of 20 g/L alkali concentration, 2 mL/L liquid-to-solid ratio, and 70℃ reaction temperature. Carbonation reaction time significantly influences the net carbon dioxide sequestration efficiency. According to calculation, carbon dioxide emission of 52.6 kg/tslag was avoided at a relatively long time of 120 min.     

论数学模型在电弧炉炼钢中的应用

通过对电弧炉炼钢理论及工艺数学模型的研究状况进行的总结和分析，提出模型的层次划分概念及层次之间的相互关系，这对指导数学模型研究和应用非常重要。     

AOD炉加料及温度制度的研究与实践

通过研究AOD炉脱碳保铬反应的热力学规律,制定了AOD炉加料制度及温度制度原则,提出了AOD炉冷料配入量、开始加料时刻、加料速度以及加料顺序的计算方法和确定方法,并将此方法应用于120t AOD炉冶炼实践,取得了较好的效果。     

宝钢连铸中间包装状态测试与分析

连铸中间包内钢水温度是炼钢生产过程的重要工艺参数之一，影响该参数的因素很多，通过对宝钢炼钢60t中间包的包衬热状态进行测试，分析了包衬蓄热状况对中间包钢水温度的影响。     

The Effect of Undercooling on Solidification of YSZ Splats

We consider the rapid solidification of a molten YSZ particle, by solving the so-called hyperbolic equations for heat and mass transfer. The hyperbolic model predicts the interface undercooling (due to thermal and solutal effects) and velocity as a function of time, as well as the yttria redistribution within the solid phase. Results are then compared to corresponding ones that we obtained from a parabolic model, to assess the extent to which YSZ solidification is influenced by nonequilibrium effects. Results indicate that these effects are limited to the early part of the solidification process when undercooling is most significant. At this stage, the interface velocity is unsteady, and solute redistribution is most evident. As solidification decelerates, the nonequilibrium effects wane and solidification can then be properly modeled as an equilibrium process.     

宝钢炼钢异常板坯的分析与控制

针对宝钢炼钢过程中的板坯异常问题,进行了现场跟踪与分析,得出炼钢过程中板坯异常主要与过热度和液面波动异常有关。研究发现,炼钢各工序间时间间隔不适宜,易造成工序间温度符合率低下;头尾坯、异钢种交接坯生产中拉速不稳定以及正常板坯浇铸过程中氩气流量过大,均易造成液面波动异常,从而导致板坯异常。通过制定相应火车时刻表、改进炼钢生产计划编排、优化连铸氩气流量等措施,有效控制了浇铸过程中过热度异常与浇铸液面波动问题,使宝钢异常板坯量得到有效的改善。     

The effect of internal stresses on diffusion in nanostructured alloys

General expressions for diffusion fluxes in binary alloys with allowance for elastic-stress fields and the nonequilibrium state of vacancies are obtained within the framework of the hole-gas model. The microscopic parameters that are included in these expressions are specified in terms of regular solid solutions. The influence of a nonequilibrium grain boundary, which for nanostructured materials is described by the model of chaotically distributed dislocations, on the activation energy of diffusion in a near-boundary zone is considered. It is shown that even at an average zero field of elastic stresses, there is observed a change in the effective activation energy. The structure of a diffusion near-boundary zone and its parameters, i.e., characteristic spatial scales and their temperature dependences, have been determined.