【作者】 赵权；

【导师】 张洪流；

【作者基本信息】 安徽理工大学 ， 化学工程， 2012， 硕士

【摘要】 生物质油作为新型能源,其分离研究备受国内外关注。本文就当前国内外生物质油分离方法进行比较分析,介绍列管式分离设备的研究进展,提出了列管式水蒸汽精馏塔是分离生物质油的有效设备。然而,目前列管式精馏塔研究甚少,尤其是流体力学性质。本文对列管式精馏塔的流体力学性质进行研究,得出以下关联式及结论：(1)自制的25B、20B、15B型布膜器布液效果较佳,经过实测得到了液量的操作下限和上限值。(2)当流型处于层流或拟层流时,液膜平均厚度可用Nusselt变形式计算确定；当流型处于湍流时,液膜平均厚度可用计算确定；试验分别得到了不同规格管径,不同流型下的相关系数。(3)随着ReL的增大,液体的波动性逐渐增强,液膜厚度沿管长逐渐成波形增厚。在某一位置上,液膜厚度与液体雷诺数的关联式为δ=a-bcReL,在不同位置上系数不同。(4)气液两相流状态下,管内液泛状态点可借助沃利斯公式确定,状态点随管径、流量及流体物性而变,通过实验关联获得了不同状态下式中的系数值及拟合式。全部携带点和流向反转点均与流体物性联系较小,而与管径有较大关系；随着管径的增加,所需进管气量均逐渐增大。(5)环状降液区的压降几乎为零；在翻卷形成区压降幅度变化较大,至与液流翻卷区的交接点时达到最大峰值；液流翻卷区与液流滞流区的压降下降缓慢,至与全部携带点后压强降不降反增。气量由空气单相流逐渐减小时,压差曲线与气量增加时相仿,只是在由空气单相流区转化为液流翻卷区的临界点处因初始反转液流量较大造成压强会有突变。本论文的试验研究揭示了生物质油用列管式精馏塔的相关流体力学性质,可为今后的工业性开发提供参考。更多还原

【Abstract】 Biomass pyrolysis oil is an important new energy, its separation research is under the spotlight by domestic and foreign. This article comparision and analysis the separation method of Biomass pyrolysis oil at present, introduced the research progress of multitube separation equipment, put forward the multitube steam distillation column is an effective method for the separation of Biomass pyrolysis oil. However, a few people have studied this device, especially the property of hydromechanics. This paper study the hydromechanics of the multitube distillation column and obtain the following correlationa formulas and conclusions:(1) The25B、20B、15B type liquid distributors by homemade is very good for liquid distributor, and measure the upper and lower limit operation of liquid flow.(2) The calculation formula of liquid film average thickness is the variable form of Nusselt when flow is layer and laminar; The calculation formula of liquid film average thickness is when flow is turbulent:and measured the coefficient of different flow pattern in various diameter.(3) With the increase of Re,, the liquid volatility gradually increase, the average liquid film thickness gradually thicken as waveform along the tube length. The relationship between liquid film thickness and liquid reynold number is δ=a-bcRel’on a certain site, the coefficient is different in various tube site.(4) The flooding point of tube can use Wallis formula in Gas-Liquid two-phase flow, the state point is depend on diameter、flow rate and fluid property, we obtain the coefficient and fitting formula of different state by experiment correlation. The complete carry up point and flow reversal point have less contact with fluid property, but have much contact with diameter. The amount of inlet air increase when the diameter is increase.(5) The liquid pressure drop almost down to zero in ring film zone; In roll forming region, pressure drop amplitude variation is big, and achieve maximum peak until the intersection point of liquid roll zone; The pressure drop decline slowly in liquid roll zone and stagnation zone, and the pressure drop is increase instead of decrease in all carry up point. The gas flow reduce in air single-phase zone, and the pressure differential curve is similar with the state of increase gas, they have a mutation because of large pressure drop made by initial reverse flow at the critical point of air single-phase flow zone into liquid roll zone.The experimental study in this paper reveal the hypermechanics of multitube distillation column of biomass pyrolysis oil, and provide a reference for future industrial development.更多还原