Modeling and optimization method featuring multiple operating modes for improving carbon efficiency of iron ore sintering process

Iron ore sintering is one of the most energy-consuming processes in steelmaking. Since its main source of energy is the combustion of carbon, it is important to improve the carbon efficiency to save energy and to reduce undesired emissions. A modeling and optimization method based on the characteristics of the sintering process has been developed to do that. It features multiple operating modes and employs the comprehensive carbon ratio (CCR) as a measure of carbon efficiency. The method has two parts. The first part is the modeling of multiple operating modes of the sintering process. K-means clustering is used to identify the operating modes; and for each mode, a predictive model is built that contains two submodels, one for predicting the state parameters and one for predicting the CCR. The submodels are built using back-propagation neural networks (BPNNs). An analysis of material and energy flow, and correlation analyses of process data and the CCR, are used to determine the most appropriate inputs for the submodels. The second part of the method is optimization based on a determination of the optimal operating mode. The problem of how to reduce the CCR is formulated as a two-step optimization problem, and particle swarm optimization is used to solve it. Finally, verification of the modeling and optimization method based on actual process data shows that it improves the carbon efficiency of iron ore sintering.     

430m~3高炉中心加焦技术生产实践

对八钢430m3高炉在中心加焦过程中应该注意的问题及得到的效果进行了一些实践对比研究,通过中心加焦技术,能够达到炉况稳顺、增产降耗,确保高炉长寿。     

GPS技术下的露天矿山爆破设计及布孔

针对某露天铁矿布孔方式及弊端，该矿山引进GPS技术并将其应用到矿山爆破设计和布孔中，在现场进行实验研究。结果表明，使用了GPS技术进行布孔，可以极大地提高孔位的布设精度，且操作简便，工作效率较之前也有较大的提高，满足了矿山精细化爆破要求，使得最终的爆破效果得到改善。据现场统计，最终爆破大块率降低40%，减少了处理大块等待时间，满足露天矿山采装的要求，获得了良好的经济效益。     

宝钢不锈带钢酸洗工艺及废水处理

以宝钢为例,对不同材质的热、冷轧不锈钢带钢提出酸洗工艺流程和设计参数,概述不锈钢各种酸洗方法的酸洗机理,介绍不锈钢酸洗后的废水处理方法。     

中厚板角轧宽展技术的研发与应用

分析了宝钢湛江中厚板厂产品结构;为提高产能和宽展工艺的生产效率,针对小展宽比轧制,提出一种新型中厚板柔性宽展轧制工艺—角轧宽展工艺。开发了角轧宽展工艺的计算模型和自动控制系统;为了验证角轧工艺的可行性和理论模型的设定精度,在宝钢湛江4 300 mm中厚板厂开展了角轧工艺工业生产试验研究,并对试验钢板几何尺寸和设备力能参数进行了实测和分析。生产表明,角轧宽展工艺能够提高宽展轧制的生产效率、降低宽展轧制的轧制力和扭矩,有利于延长设备寿命;角轧宽展控制系统具有较高的控制精度,宽展能力满足中厚板小宽展比的生产需求。     

厚规格调质高强度船板心部冲击不合格原因分析

为找出厚规格调质高强度船板心部冲击不合格的原因,通过光谱仪、显微镜、SEM EDS能谱仪等仪器,对心部试样的成分、组织进行分析,结果表明：心部冲击不合格的原因是中心偏析带上存在大尺寸MnS夹杂与Nb、Ti的夹杂物,以及较多Al2O3夹杂和Mg、Ca等外来夹杂物。分析认为,通过提高钢水洁净度,避免钢水二次氧化污染,控制钢包炉(LF)精炼周期与操作,降低钢水过热度,优化电磁搅拌和轻压下工艺,采用堆垛缓冷等措施,可以提高铸坯内部质量,减少中心偏析和夹杂,同时通过适当优化铸坯加热、轧制及热处理工艺,可以有效提高心部冲击韧性。     

60Si2Mn弹簧钢的断裂失效分析

60Si2Mn弹簧钢在正常服役过程中出现断裂,断裂后部分原件损失,根据材料力学原理,并结合断口特征,确定断裂起源位置;采用光学显微镜、扫描电镜、体视显微镜、直读光谱仪等对残留端口的显微组织、宏微观断口形貌和化学成分等进行观察和检测分析,以确定断口起源和断口特征。结果表明:由于生产过程操作不当,弹簧表面存在微裂纹,同时由于喷丸处理的工艺不恰当,造成弹簧表面形成较深的应力线,应力线发展成为沿应力线的开裂和脱落。这些微裂纹、开裂以及脱落,作为弹簧的疲劳断裂源,造成了弹簧的断裂。     

金属退火硬化现象及机理的研究进展

通常金属进行退火时都会发生软化现象,而对于一些特殊的金属或者合金,将出现退火硬化的反常现象。对纯金属、铜合金、镍钨合金、锌铝合金和铝合金等体系中退火硬化现象及机理进行了总结与分析。铝钪、铝镱和铝锆系合金中存在铸态直接退火硬化现象,而其它合金体系需要进行冷变形才会出现退火硬化现象。退火硬化的机理主要包括:晶界溶质偏析、晶界弛豫、第二相颗粒的晶界钉扎、位错源限制硬化、溶质偏析对孪晶边界迁移或位错滑动的钉扎效应、退火孪晶、第二相纳米粒子强化等。     

Achieving the best glass former in a binary Gd–Co alloy system

In this work, the best glass former in a binary Gd–Co alloy system has been designed by thermodynamic parameter γ^⁎, which has been proved to be valid in the prediction of glass forming ability (GFA) of other binary alloys. A metastable phase has been observed in some Gd–Co melt-spun ribbons and its composition has been ascertained. By analyzing the effect of the metastable phase on the GFA of the Gd–Co binary alloys, we predict the Gd₅₀Co₅₀ alloy as the best glass former in the binary alloy system. The prediction has been confirmed by the experimental results, proving the validity of the parameter γ^⁎ in the Gd–Co binary alloys.