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21.
双气路循环流化床压力平衡的实验研究   总被引:1,自引:0,他引:1  
在Φ800mm×12000mm流化床装置上,用多点压力测量仪对双气路循环流化床各部分的压力分布进行了实验。实验结果表明,颗粒单循环回路的压力平衡图与装置的运行状态、颗粒的循环量密切相关。整个颗粒的循环回路压力曲线呈双8字缠绕式,随质量流率的减少形状发生畸变;补气循环回路与不补气循环回路的压力分布相似,但料腿沉降段的压力降低;提升管内没有明显的稀密相交界面,而料腿内存在着稀密相的交界面,料腿下部的高密度移动床是保证流化床正常运转的必要条件。  相似文献   
22.
船用柴油机排气消声器性能试验台的研制   总被引:4,自引:0,他引:4  
设计并建造了一种用于船用柴油机排气消声器声学和气动性能试验研究的台架.台架以两个高压离心风机串联增压的方式作为风源,采用航空燃气轮机燃烧室作为燃烧器.烟气的温度和流量由控制系统调节实现,控制系统分自动控制和手动控制,方便操作.初步的试验结果表明:研制的台架气体流量范围0~8 m^3/s,温度调节范围20℃~600℃,可以满足2000 kW以下发动机排气消声器的试验要求.  相似文献   
23.
张春贺 《中国矿业》2005,14(7):13-15,33
加拿大是一个石油天然气净出口国.是美国最重要的能源进口国之一。随着西部省区油田的成熟化,加拿大自1999年实施开发油砂和海域石油资源项目后,石油产量开始增长。业内人士分析预测,加拿大油砂石油的产量在不久将会有更显著的提高,并可以补偿上其常规原油递减的产量。加拿大油砂石油生产和煤层气开发所取得的成功.很可能是今后世界石油工业的过渡发展方向。  相似文献   
24.
Hydrodynamic behavior of a magnetofluidized bed is investigated over a wide range of magnetic-field intensity values as a function of superficial air velocity. The bed comprises of different proportions of copper and iron particles and is contained in a Plexiglas column of 0.102?m internal diameter. The uniform constant magnetic field is created by a Helmholtz electromagnet. In particular, the bed pressure drop is measured as a function of superficial air velocity and characteristic bed voidage and fluidizing velocities are determined at minimum fluidization and bubbling bed conditions. These characteristic properties of the magnetically stabilized fiuidized beds are reported as a function of magnetic-field intensity, and are correlated by suitable expressions. These will be useful for prediction purposes related to design and operation.  相似文献   
25.
Heat transfer coefficients were measured for 227 and 87 micron size particles of silica sand in a 102 mm dia. and 5.5 m tall circulating fluidized bed made of plexiglass. Effects of solid circulation rate, fluidization velocity, bed density and particle sizes were studied. The heat transfer coefficients were calculated from the temperatures measured along the axis of a 25 mm dia 100 mm long cylindrical heat flux meter.  相似文献   
26.
三相生物流化床的相含率及气液传质性能研究   总被引:4,自引:1,他引:4  
采用内循环三相生物流化床,用清水进行了在不同活性炭载体加入量下,当进气量改变时流化床内的气液传质性能的实验,认为当Ug≥0.75m^3/h时,随着气体流量增加,可改善流化床的氧传质效率,缩短循环时间和混合时间,提高气含率,但过高的气体流量(Ug≥1.1m^3/h)并不利于流化床的操作。载体加入量增加,会导致氧传递性能下降,循环时间和混合时间缩短,气含率减小。  相似文献   
27.
Characteristics of CO2 hydrogenation were investigated in a fluidized bed reactor (0.052 m IDxl.5 m in height). Coprecipitated Fe-Cu-K-Al catalyst (dρ=75–90 Μm) was used as a fluidized solid phase. It was found that the CO2 conversion decreases but the CO selectivity increases, whereas the space-time-yield attains maximum values with increasing gas velocity. The CO2 conversion has increased, but CO selectivity has decreased with increasing hydrogenation temperature, pressure or H2/CO2 ratio in the fluidized bed reactor. Also, the CO, conversion and olefin selectivity appeared to be higher in the fluidized bed reactor than those of the fixed bed reactor. Presented at the Int’l Symp. on Chem. Eng. (Cheju, Feb. 8–10, 2001), dedicated to Prof. H. S. Chun on the occasion of his retirement from Korea University  相似文献   
28.
循环流化床物料气动控制的试验研究   总被引:2,自引:0,他引:2  
高鸣  吕清刚  贺军 《锅炉技术》2006,37(1):30-33
研究了一种用于外置换热器进料控制的新型气动控制阀的冷态控制特性,包括控制风与物料流率的关系,结果表明该气动控制阀能够很好地调节进入外置换热器的物料流率,并得出各股控制风对进入外置换热器物料流率的控制特性.  相似文献   
29.
An incineration test of a toxic chemical organic waste liquid was conducted on a circulating fluidized bed (CFB) incinerator. The flue gas was measured online with the advanced SAE-19 flue gas analyzer. The effects of several factors, in terms of flow rate of waste liquid, ratio of waste liquid injected into dense bed of the CFB, excess air coefficient, the secondary air fraction and bed temperature on NO x emissions, were verified. The experimental results show that NO emissions in flue gas increase with increase in the flow rate of the waste liquid injected into the bed or the excess air coefficient or the bed temperature and those decrease with increase in the ratio of waste liquid injected into the dense bed of the CFB or the secondary air fraction. During the test runs, NO x concentration in flue gas met the national regulation on NO x emissions due to suppressive effect of low temperature and staged combustion in CFB on NO x formation. This paper was presented at the 6 th Korea-China Workshop on Clean Energy Technology held at Busan, Korea, July 4–7, 2006.  相似文献   
30.
The combustion characteristics of a mixture of anthracite and bituminous coal were studied in a 0.155 m i.d. fluidized bed combustor (FBC). The properties of the pressure fluctuation for the bed such as the standard deviation, cross-correlation function, dominant frequency and the power spectral density function were obtained through statistical analysis. To interpret the combustion characteristics in the FBC with uniform or multi-sized particles of anthracitebituminous coal mixture, the properties of pressure fluctuation were determined as a function of the particle size distribution and anthracite mixing fraction. In the present work, it is known that the combustion region could be obtained from the analysis of pressure fluctuation properties, and the mixed-firing of anthracite-bituminous coal is related to the reaction models of both coals and particle size distribution. Moreover, the relation between coal size distribution and static mean pressure, and the ignition region could be obtained from the mean pressure profile.  相似文献   
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