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991.
移动床除尘过程数学模型建立及机理讨论 总被引:4,自引:1,他引:4
在C.Tien固定床深层过滤数学模型基础上,通过引入移动床除尘比沉积率σ概念并考虑惯性碰撞、拦截、重力沉降、扩散机理的作用,建立了完整的颗粒移动床深层过滤过程数学模型,以此为基础结合工程应用中实测的粉尘数据范围计算了除尘效率,详细讨论了各种除尘机理及操作条件对除尘效率的影响。 相似文献
992.
A new experimental set-up and a new simulated moving bed (SMB) operation are presented in this work. A desktop SMB unit developed as a modification of the commercial AKTA explorer working platform has been utilized for the separation of different mixtures of nucleosides. Both two fraction and three fraction SMB separations have been carried out, the latter made possible by the adoption of a new SMB configuration and operating mode (three fraction SMB, 3F-SMB, operation). Experiments demonstrate the feasibility of the 3F-SMB operation, and confirm the trends predicted based on considerations about retention of the components to be separated along the unit. 相似文献
993.
循环流化床锅炉氮氧化物的生成与分解模型 总被引:1,自引:0,他引:1
在国内外研究基础上,依据循环流化床锅炉炉内氮氧化物(NO和N2O)的生成与分解特性,建立了一个以化学反应动力学为基础的炉内NO和N2O的生成和分解模型,模型有机地结合在已有的循环流化床锅炉总体数学模型之中。模型对一台75t/h循环流化床锅炉炉内氮氧化物的生成和分解特性的模拟预测结果与工业试验结果吻合良好。模型的预测和工业试验表明循环流化床锅炉的氮氧化物(NO和N2O)的排放受锅炉运行参数如温度、一二次风比例等的影响,可以通过调整锅炉运行参数来控制锅炉氮氧化物的排放。 相似文献
994.
Summary A selective GC column for the determination of vinyl chloride monomer in air has been developed. The 1.5m×1/8 column is filled with a mixture of Porapack S and T (8020). The selectivity was tested with 21 possible pollutants. All of the tested compounds were separated from vinyl chloride. 相似文献
995.
Liuye Mo Xiaoming Zheng Yuhui Chen Jinhua Fei 《Reaction Kinetics and Catalysis Letters》2003,78(2):233-242
The effects of the Ni loading, total feed flow rate, prereduction temperature, reaction temperature and feed gas ratio for
combination of CO2 reforming and partial oxidation of CH4 over Ni/Al2O3 were investigated using a fluidized bed reactor. Methane conversion to syngas was drastically enhanced using a fluidized
bed reactor over Ni/Al2O3 catalyst calcined at high temperature. The fluidized bed and the fixed bed reactor were compared and a promoting mechanism
of the fluidized bed reactor was proposed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
996.
997.
在实验室小型流化床反应器中研究了福建龙岩无烟粉煤纸浆黑液富氧催化气化的特性,考察了纸浆黑液催化剂添加量不同时氧体积分数变化对碳转化率、产气率、煤气组成与热值的影响。结果表明,纸浆黑液催化和富氧气体燃烧的双重作用明显地提高了煤的碳转化率和煤气有效组成;纸浆黑液中钠碱对煤焦气化的催化与对煤灰分中SiO2和Al2O3等氧化物的熔制反应同时发生并存在着竞争;纸浆黑液中钠碱对高温碳与气化剂之间多种反应表现出不同程度的促进。龙岩无烟粉煤在纸浆黑液富氧催化气化时适宜操作条件是氧的体积分数40%和蒸汽/富氧比为1.4kg/m3~2.0kg/m3。碳转化率94%、煤产气率为3.62m3/kg、煤气热值为7.33mJ/m3。 相似文献
998.
999.
使用“柠檬酸法”制备了一系列较高比表面的W-Fe-MgO催化剂,在较易放大的流化床反应器中,1 100 ℃ H2气流中分解CH4,制得SWCNTs管束,单管直径在1~3 nm,最高碳产率36 mg/100 mg催化剂.经TEM、微区Raman、程序升温氧化(TPO)测量表明,产物中无定形碳、MWCNTs均较少,为纯度较高、缺陷较少的SWCNTs.从EDAX结果并参考W-Fe相图推测SWCNTs生长的催化剂活性相可能为W、Fe的金属间化合物或富Fe的固溶体. 相似文献
1000.
Changes in bed expansion are frequently encountered during an expanded bed adsorption, such as during the initial bed expansion, feed loading and washing processes. We have here studied the changes of local particle size distribution and bed voidage of an expanded bed in the initial bed expansion process as well as those during the changes in mobile phase viscosity, which imitated feed loading and column washing processes. Using a glass column modified with three side sampling ports and Streamline AC as the solid phase, experimental measurements on a series of operation moments during the transient processes were carried out by sampling the particles from within the column at different axial positions. In the initial bed expansion process, the gradual formation of an axial classification from a settled bed to a stable expanded bed was first displayed. By changing the mobile phase from water to 10% (w/w) glycerol solution or vice versa, the variations in both the particle size distribution and bed voidage corresponding to the increase or decrease of the bed height caused by the changes of the mobile phase viscosity were examined as well. The transient changes of the local particle size distribution and bed voidage first occurred in the bed bottom and then progressed from bottom to top along the axial direction. However, the changes of bed voidage at different axial positions were not unidirectional. That is, by changing the mobile phase to the high-viscosity glycerol solution, a constant increase of the bed voidage was observed in the bed bottom, while a distinct decrease of the bed voidage before its increase was involved at the middle and top positions. This is ascribed to the compression effect caused by the upward movement of the lower part particles. 相似文献