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841.
概述了过热蒸汽对烧碱蒸发的危害,和采取特殊方式的增湿减温措施取得的良好效果:汽耗由5.1t/t降到3.8t/t,节汽约1万t/a,节约资金50万元/a,产量得到很大提高,使烧碱的运行状态得到改善。但仍存在一定问题尚需改进。 相似文献
842.
Rakshith Sachitanand Mohammad SattariJan-Erik Svensson Jan Froitzheim 《International Journal of Hydrogen Energy》2013
In recent years, a number of ferritic interconnect materials for use in solid oxide fuel cells (SOFC) have been developed and are now commercially available. Although similar, there are substantial variations in minor alloying elements. This study compares the oxidation performance of five such interconnect materials: Crofer 22 H, Crofer 22 APU (ThyssenKrupp VDM), Sanergy HT (Sandvik Materials Technology), ZMG232 G10 (Hitachi Metals) and E-Brite (ATI Allegheny Ludlum). 相似文献
843.
Recently a low cost cooking device for developing and emerging countries was developed at KIT in cooperation with the company Bosch und Siemens Hausger te GmbH.After constructing an innovative basic design further development was required.Numerical investigations were conducted in order to investigate the flow inside the combustion chamber of the stove under variation of different geometrical parameters.Beyond the performance improvement a further reason of the investigations was to rate the effects of manufacturing tolerance problems.In this paper the numerical investigation of a plant oil stove by means of RANS simulation will be presented.In order to reduce the computational costs different model reduction steps were necessary.The simulation results of the basic configuration compare very well with experimental measurements and problematic behaviors of the actual stove design could be explained by the investigation. 相似文献
844.
在环境参数可控风洞中对影响蒸发的风速、水气温差、水温、相对湿度等物理量进行系统试验。试验结果表明蒸发系数取决于风速的强迫对流和水气温差的自由对流。分析试验数据得到了水面蒸发系数的建议公式和相应的水面散热系数公式以及附加蒸发系数公式。用参数变幅很大的天然水体和受纳废热水体的实测资料和研究成果检验了建议公式的通用性。建议公式已为DL/T5084—98《电力工程水文技术规程》及GB/T50102—2003《工业循环水冷却设计规范》推荐应用于计算水面蒸发、水面散热及附加蒸发。 相似文献
845.
Experimental work was undertaken to study the thermal performance of three different pond cells under actual climatic conditions of Qatar. The first cell was an open pond. In the second unit, a finned radiator, painted black, was placed over the pond. In the third cell, the water was contained in a polyethylene bag. Experimental results indicated that the exposed pond cell came out best, when considered in terms of how quickly the temperature of the stored water could be reduced, and how low that temperature could be. The water in the exposed pond was cooled directly (by evaporation and radiation to sky) whereas in the case of the finned radiator cell, heat had to be transferred from the stored water to the radiator, and then from the radiator to the surrounding. In the case of water-in-bag cell, evaporation was eliminated and radiative exchange with the sky was reduced due to the partial transparency of the polyethylene bag (in the infrared region). 相似文献
846.
Yuji Tatemoto Yoshiyuki Bando Koji Oyama Keiji Yasuda Masaaki Nakamura Yasuhiro Sugimura Masahito Shibata 《Drying Technology》2001,19(7):1287-1303
The effects of operational conditions on the drying performance in closed superheated steam drying were examined theoretically and experimentally. The vapor generated from the sample was circulated in the drying chamber. In the theoretical analysis, the replacement of air with vapor in drying chamber and the convective vapor transfer in sample were considered. At the start of drying, the drying chamber was filled with air. As the drying proceeded, the air was replaced with the vapor generated from sample. The calculated results explained the characteristics of experimental data. The pore diameter of sample had little effect on the drying characteristics. During the internal evaporation period, the evaporation occurred in the narrow zone, which moved from the surface to the bottom of sample. The convective vapor transfer in sample had a significant influence on the drying performance. The excess increments in temperature and velocity of drying gas hardly contributed to shortening the drying time. 相似文献
847.
848.
挥发性有机物(Volatile Organic Compouds,VOCs)是仅次于颗粒污染物的第二大气污染物,对环境和人类健康造成了极大的危害。本文介绍了真空薄膜蒸发和分子蒸发的原理,特点和应用,并介绍了真空薄膜蒸发-冷凝工艺在分离HDI缩二脲中游离单体中的应用,最后并提出了挥发性有机物污染控制的途径。 相似文献
849.
创新型处理高污染废水的低温常压蒸发技术 总被引:1,自引:0,他引:1
农药废水对环境造成严重污染。农药废水处理旨在降低农药生产废水中污染物浓度,提高回收利用率,从而尽量达到无害化。创源环保(CWT)公司开发的低温常压蒸发工艺能在处理废水时实现大幅地低能耗运行和低维护成本,同时也提高了回收废水中有价值的物质的可能性。 相似文献
850.
Simulation results for continuous vacuum evaporation crystallization obtained by Aspen Plus and experimental results for semi‐batch vacuum evaporation crystallization are presented. In the crystallization experiments, the fixed heat duty was used to compare the water evaporation rates and crystal properties obtained at different pressures. The solution selected was aqueous glycine. It has the ability to form a number of different crystalline polymorphs, which allows it to exhibit a variety of different physical properties while maintaining its chemical properties. X‐ray diffraction results demonstrated that mainly the γ‐crystal form is produced under the conditions applied in vacuum evaporation crystallization. 相似文献