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11.
一维炉是一种研究煤的热解燃烧和结渣等方面的实验系统,可用于模拟电厂煤粉的燃烧特性。以元宝山褐煤为燃料,介绍了一维炉的结构和功能,并对系统的可靠性进行了验证,利用烟气分析仪及热重分析仪对燃烧后的尾部烟气及灰渣进行了分析测定。结果表明:尾部烟气含氧量与灰渣可燃部分剩余量均在理论计算值的误差允许范围内,说明一维炉密封良好,系统内各部分正常运行,对维炉的调试和研究具有一定的参考意义。 相似文献
12.
Three kinds of hot rolled steel slabs, viz. high strength steel, bake hardened steel and low carbon steel, were oxidized isothermally
between 1100 and 1250 °C for up to 2 hr in 1 atm of air and an 85%N2–10%CO2–5%O2 gas mixture. The steels were oxidized in a similar fashion in both the atmospheres. The oxidation process followed an initial
linear rate law, which then gradually transformed to a nearly parabolic rate law. Thick, porous and nonadherent scales formed
rapidly, due to the high oxidation temperature. The scales formed consisted of Fe2O3,(Fe2O3+Fe3O4), (Fe3O4+Fe2O3 +FeO) and (FeO+Fe3O4) from the outer surface. The presence of supersaturated oxygen beneath the scale resulted in grain boundary oxidation and
the formation of internal oxide precipitates. 相似文献
13.
A. Fernere L. Lestrade A. Rouanet A. Denoirjean A. Grimaud P. Fauchais 《Journal of Thermal Spray Technology》1994,3(4):362-370
An original process of superficial thermal treatment is described. This process has been successfully applied to partially
stabilized yttria-zirconia coatings (ZrO2-Y2O3) to increase the lifetime of the thermal barriers. A thin superficial layer was melted, and morphological transformations
were observed. A microstructural comparison between as-sprayed layers and thermally treated layers is presented. 相似文献
14.
国产60吨铝熔炉感应式电磁搅拌器的应用 总被引:1,自引:0,他引:1
介绍了60t炉底感应式电磁搅拌器的应用方案、工作原理、设备组成和安装形式,阐述了电磁搅拌器对熔融金属化学成分均匀性、温度均匀性以及金相组织的影响,分析了电磁搅拌的整体运行效果,并总结了电磁搅拌器的应用特点。 相似文献
15.
16.
Petr SCHILL TANG Wei 《玻璃与搪瓷》2007,35(F08):94-96,100
The goal of the latest strategy in glass companies is to decrease the cost of production while maintaining or increasing the glass quality. One of the perspective ways is to install the electric boosting into the existing furnace or to build the new furnace including the electric boosting. This strategy may be surprising as electric energy is generally more expensive than gas or oil (considering the cost per unit energy) but because of efficiency of use ( direct glass - melt heating by Joulean heat) it is inevitably cost effective.
The use of the CFD modeling capability for electro - boost designing is presented in this contribution. The Glass Service Glass Furnace Model ( GS - GFM ) is used for investigating the optimal electrode arrangement and phasing, and moreover, for increasing the glass quality during the electro - boost applying. 相似文献
17.
Slag samples, hot‐metal samples and hot‐metal temperatures were obtained during tapping of two blast furnaces. Sampling was carried out at different time points during tapping of three separate heats. The size distribution and composition of metal droplets found in the slag were determined using scanning electron microscopy. Only metal droplets above 0.75 μm could be counted and analysed. All droplets were below 8 μm in diameter and the great majority of these droplets were found to be between 0.75 and 2 μm. The size distribution did not differ significantly for different slag samples. Iron was the main droplet component. Electron probe microanalysis showed that the droplets contained small amounts of carbon. The percentage of the area in a studied cross‐section that was covered with metal droplets varied between 0.01 and 0.07%. Calculations based on Stoke's law showed that the distance droplets travel in the slag is in the micron range. Slag samples taken in the beginning of slag tapping contained more droplets than those taken in the middle of slag tapping, an indication that most droplets can be found in the area near the furnace wall. Some droplets were determined to have magnesium enrichment at the external surface. 相似文献
18.
提高高炉清循环冷却水系统浓缩倍数的对策研究 总被引:1,自引:0,他引:1
通过对宝钢1号高炉清循环冷却水系统的质能平衡测试和理论分析计算,找出了清循环水系统浓缩倍数偏低的真正原因,并提出了相应的技术措施,所做工作对同类系统有重要的指导意义。 相似文献
19.
石墨炉原子吸收测定化探样品中痕量金的研究 总被引:6,自引:1,他引:6
采用以王水分解样品,泡沫塑料富集,硫脲解脱,石墨炉原子吸收分光光度计测定微量金。研究了测定时干燥温度和时间的选择,原子化温度和时间的选择,灰化温度和时间的选择,以及王水体积分数对吸附效果等条件对测定结果的影响。该方法检出限为0.2×10-9,经国家一级分析标准样品验证,结果与标准值相符。 相似文献
20.