宣钢高炉合理炉料结构熔滴试验

 对宣钢12种含钛高炉炉料的化学成分及熔滴性能测试结果进行综合分析,给出宣钢2号高炉（2 500 m3）、3号高炉（2 000 m3）、4号高炉（1 800 m3）不同原料条件下最佳的炉料结构,并对3组炉料结构进行比较。分析认为,2号高炉熔滴性能最好的炉料结构为4号方案,[S]值最小为322 kPa·℃,3号高炉熔滴性能最好的炉料结构为5号方案,[S]值最小为786 kPa·℃,4号高炉熔滴性能最好的炉料结构为11号方案,[S]值最小为790 kPa·℃;3号、4号高炉使用的炉料碱度与2号高炉相比较高,这是造成3号、4号高炉炉料最大压差[（Δpmax）]值高的主要原因;2号高炉使用炉料的含铁品位较高,大于57%,且渣中的MgO质量分数较低,因此炉料在软熔滴落带渣量相对较少,渣的流动性较好,熔滴性能优于3号、4号高炉。     

高炉综合炉料熔滴性能及其预测模型

含铁炉料冶金性能和高炉炉料结构优化是实现低碳低成本炼铁的重要举措。熔滴试验对于全面把握含铁炉料的冶金性能具有重要意义。由于钢铁企业内各高炉炉料结构不同且不断调整,加上熔滴试验成本较高且检测时间较长,多数企业仅检测单种含铁炉料的熔滴性能,操作者难以根据炉料结构的变化预知综合炉料的冶金性能、进而调整冶炼制度。在对永钢高炉常用单种含铁炉料进行熔滴试验的基础上,根据永钢典型炉料结构,研究不同炉料结构条件下综合炉料的熔滴性能。同时,利用回归法建立了单种炉料配比及熔滴性能与综合炉料熔滴性能间的关系模型,模型具有一定适用性,可为高炉炉料结构优化及提前制定合理的操作制度提供参考。     

宣钢高炉含铁炉料熔滴性能

对宣钢高炉炉料结构进行了熔滴性能试验研究。单矿的熔滴试验结果表明:宣钢常用的2种烧结矿软化性能较好,但滴落性能较差,1 520℃仍未滴落;3种球团矿中自产球总体熔滴指标最好但软化区间最长(313℃);2种块矿中PB矿开始软化温度最低软熔区间最长,试验中未能滴落。蒙古矿软熔性能较好,但滴落温度高达1 518℃。通过对15种配矿方案进行的熔滴试验,结果表明:降低烧结矿配比,提高PB矿比例可改善炉料的熔滴性能。在试验条件下,配矿方案为"烧结矿68%+球团矿16%+PB矿16%"的炉料结构熔滴性能最佳。     

高炉含铁炉料的软熔行为试验研究与表征

目前铁矿石熔滴性能的评价指标繁多,在实际应用中存在诸多不便,同时各指标之间的内在关联缺乏深入探索.本文基于冶金传输原理相关基础理论提出新的表征方法,该方法通过对熔滴性能的影响因素进行量纲分析,得到熔滴性能指数(SDI);随后借助熔滴设备采集实验过程中的基础参数,得到不同炉料的SDI值.试验结果表明:炉料的SDI值越小,...     

钒钛铁矿石的还原,熔滴性能及高炉炉料结构的探讨

研究了各种类型钒钛铁矿石(不同碱度烧结矿以及球团矿和块矿)的低温、高温还原性及熔滴性能。在此基础上探讨了全钒钛铁矿石高炉冶炼的合理炉料结构。认为:高钛型钒钛铁矿石高炉冶炼的最佳炉料结构是:高碱度烧结矿加酸性氧化球团矿;在攀钢现有工艺和设备条件下,应实行提高烧结矿碱度的方针。     

湘钢二烧二期工程上马后合理炉料结构研究

通过对湘钢高炉可能使用的几种炉料结构的熔滴性能和还原性能的试验研究表明,湘钢二烧二期工程合理的炉料结是采用78％烧结矿＋15％澳矿＋7％球团矿。     

莱钢高炉用含铁炉料熔滴性能试验及分析

对莱钢常用的含铁炉料单矿及混合搭配进行了熔滴性能试验,通过试验分析:高碱度烧结矿具有良好的抗变形能力,优良的熔滴性能;酸性料中D块矿熔滴性能优于J球团;三元搭配结构中,随着D块矿配加比例增加,熔滴性能改善,更有利于高炉顺行。莱钢目前较适宜的炉料结构为"70%A烧结矿+(0～10%)J球团+(20%～30%)D块矿",应在30%范围内增加D块矿使用比例。     

高炉内添加半焦对料柱熔滴特性及焦炭溶损的影响

随着“碳达峰”“碳中和”政策的推进,钢铁企业面临着超低碳排放的压力,降低焦炭消耗是实现高炉低碳冶炼的重要举措之一,半焦具有与焦炭相近的理化性质,且能满足高炉炼铁的基本需要,可作为焦炭的替代品。模拟高炉实际工况对添加半焦后的炉料进行了熔滴特性及焦炭溶损程度的相关研究,进而探讨半焦替代焦炭用于高炉炼铁的可行性。结果表明,矿焦混装比未混装时的熔滴性能更优,当添加半焦比例从30%降低到10%时,熔滴特征值S由774 kPa·℃下降至597 kPa·℃,最大压差ΔP_MAX由13.66 kPa降低到11.79 kPa,软化区间变宽且位置下降,熔融区间收窄变小,软熔区间大小和位置逐渐接近于混装焦炭时的情况,料柱的透气性良好;添加半焦后的熔滴物相中渣相成分更为稳定,且Fe的还原度更高;添加半焦能够在一定程度上减小焦炭的孔隙率,降低焦炭的溶损程度,对焦炭起到良好的保护作用,改善料柱的透气性。本研究证明半焦替代冶金焦炭有效可行,为高炉使用半焦提供理论基础和技术指导。     

Randomized single-subject experiments and statistical tests.

The importance of intensive study of the individual subject in counseling research and the importance of the development of appropriate designs and analytical procedures for single-subject research has been recognized. Single-subject experiments are not always possible or ethical, but when they can be performed, treatment times should be randomly assigned to treatments, as this randomization is essential to provide the basis for a statistical test. The assumption of random sampling is not met in single-subject experiments. However, the data from a randomized single-subject experiment can be analyzed by use of a randomization test because such tests do not require random sampling. Randomized single-subject experiments can be helpful in determining what is best for a particular client, and systematic replications of such experiments can help in generalizing to other subjects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

气泡和液滴的碰撞和聚合现象

采用水模型实验和高速摄像技术模拟了钢液中气泡与液滴碰撞聚合的现象和机理。根据韦伯数We和碰撞参数B的关系,气泡和液滴的碰撞结果分为聚合、反弹和拉伸分离3种。聚合分为靠近碰撞、形成液膜、形成稳定接触面、滑移、稳定上浮等过程;反弹分为靠近碰撞、形成液膜、滑移分离等过程;拉伸分离分为靠近碰撞、形成液膜、形成接触面和共同体、形成颈部、断裂等过程。当We很小时,气泡和液滴会发生聚合。随着We的增大,B适中时,两者聚合;B过小,两者反弹;B过大,两者拉伸分离。在实验的We范围内,3种结果中聚合情况最多。由此,根据相似性可以解释在钢液中少见液滴夹杂物的原因。     

Univariate versus multivariate tests in repeated-measures experiments.

The usual univariate test for the repeated-measures effect in a 1-way design rests upon an assumption of uniform variances and covariances. The standard test of this assumption is shown to have acceptable power only when the multivariate test of the hypothesis is essentially as powerful as the univariate test. A modified form of the univariate test, not requiring the assumption of uniformity, is compared to the multivariate test with respect to power. Depending on the variance-covariance structure of the data and the alternative hypothesis, the univariate test ranges from somewhat better to much worse than the multivariate test. There are possibly interesting experimental effects which the univariate test is virtually powerless to detect. (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Correlation between aerobic and anaerobic resistance to metronidazole in trichomonads: application of a new computer program for permutation tests

An indispensable step of any comparative study is testing the concordance between the distribution of phenetic traits and the evolutionary history of the taxa under study. Here we present a computer program TREEPT which can perform these tasks on the basis of a permutation test. The use of the program was demonstrated on trichomonad drug sensitivity data. The program can also perform permutation tests analogous to the t-test, analysis of variance (ANOVA) and correlation analysis and is available at http://www.natur.cuni.cz/flegr/PROGRAMS/+ ++TREEPT.ZIP and http://www.karlin. mff.cuni.cz/-zaboj/treept.