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121.
122.
介绍了变压吸附(PSA)技术在邯钢冷轧工程中应用于焦炉煤气提氢的工艺及特点。通过与水电解制氢方法进行比较,指出焦炉煤气变压吸附制氩装置具有投资少、产量大、运行费用低等优点。 相似文献
123.
Chiu Liu 《Canadian Metallurgical Quarterly》2005,131(2):161-166
Van der Waals force between neutral molecules is employed to characterize the interaction among molecules in asphalt cement. Several important consequences emerge from the consideration. The brittle strength of the asphalt binder is shown to be linked to the well depth of the Van der Waals potential and the mesoscopic cracks present within the asphalt binder. Moreover, the elastic modulus of asphalt binder is analytically related to the potential well depth. The strength of the asphalt concrete (AC) is estimated by considering aggregate surface characteristics and the adhesion strength between asphaltenes or resins and molecules of aggregates. These predictions can help design asphalt concrete pavement. Formulas for predicting the binder strength and the interfacial breaking strength between aggregates and binders are derived. These results are supported by reported data. Furthermore, an analytic expression for the strength of AC is given at temperature below the AC glass transition point. 相似文献
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125.
介绍了广钢焦化厂焦炉局部吊顶翻修的工艺及应用情况,并对其实践进行了总结,说明焦炉局部吊顶翻修技术在晚期焦炉维护上具有广泛的应用和推广价值。 相似文献
126.
艾萨炉渣和转炉渣混合贫化机理的探讨 总被引:1,自引:2,他引:1
从贫化电炉处理艾萨炉渣和转炉渣的特性出发,分析和探讨了氧势、锍品位、Fe3O4、渣含铜之间的关系,以及Fe3O4还原的热力学和动力学条件。指出了贫化电炉的控制重点是Fe3O4还原以及还原剂的选择。 相似文献
127.
Liangcai Zhong Yingxiong Zhu Maofa Jiang Zhengping Qu Yishan Za Xingyu Bao 《国际钢铁研究》2005,76(9):611-615
The effects of a conventional lance tip with 4 normal nozzles and a lance tip with 4 twisted nozzles on slag splashing were investigated. A cold model for LD converters, Jiuquan Iron & Steel Co., was established and the amount of slag splashed onto the model walls was measured in the cold modelling experiments. The results from the experiments show that at low top gas flow rate the amount of slag splashing for the tip with twisted nozzles is less than that for the conventional tip, whereas at high top gas flow rate the amount of slag splashing for the nozzle twisted lance is greater than that for the conventional lance. For the nozzle twisted lance tip, slag splashing rates increase with increase in slag amount, lance height and top gas flow rate and the maximum amount of slag splashing for the tip with twisted nozzles can be obtained under the process parameters of 47.6 Nm3/h gas flow rate, 12% slag amount and 247 mm lance height. More slag droplets can be directed onto the cone with a nozzle twisted lance tip than with a normal lance tip at high top gas flow rate. 相似文献
128.
The spark‐induced modified optical emission spectroscopy (OES) technique developed by Ovako Steel makes it possible to rapidly determine inclusion characteristics in steel samples. In earlier investigations using the modified spark‐induced OES technique for steel samples taken from billets, predicted oxygen contents agreed well with results from conventional melt extraction analyses. In this investigation, samples taken during ladle treatment in an ASEA‐SKF ladle furnace were analysed using the modified OES technique. When comparing the results with inclusion characteristics determined by conventional analysis, similar trends were found. Plant trials were also carried out where three different top slag compositions were used. The purpose was to evaluate if the modified OES technique can be used to study the effect of changes in the refining operation on inclusion characteristics. Results indicated that the modified OES technique could be used to determine the effect of a changed slag composition on the inclusion characteristics in the steel. Since the modified OES method provides rapid feedback of inclusion characteristics, it has the potential of being used for faster optimisation of ladle refining operations. 相似文献
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130.
以国内外钛渣电炉生产实践为例,提出影响钛渣电炉炉体寿命的因素。从技术和经济的角度上,提出延长其使用寿命、降低造价成本的措施,并在某厂新建6300kVA钛渣电炉上实施,取得良好的生产效果。 相似文献