A new one parameter viscosity model for binary mixtures

The Grunberg & Nissian equation with one parameter is widely recommended in the viscosity calculation. However, it is demonstrated that this equation fails to generate satisfactory results for size‐asymmetric mixtures containing large and small molecules. In this work, a new one parameter viscosity model for binary mixtures has been developed on the basis of Eyring's absolute reaction rate theory and the Flory‐Huggins equation. The concept of molecular surface fraction is introduced for modeling liquid mixture viscosities. The viscosity calculations of the new equation are compared with the Grunberg & Nissian equation for a broad range of chemical mixtures including 527 binary systems (containing 63 binary ionic liquid cosolvent systems) and total 17,268 viscosity points. The new equation was found to have an improved performance over the frequently employed Grunberg & Nissian equation, especially for size‐asymmetric mixtures containing large and small molecules. © 2010 American Institute of Chemical Engineers AIChE J, 57: 517–524, 2011     

过氧化物交联聚乙烯的力学性能研究

采用过氧化物交联方法研究了交联聚乙烯的工艺、配方和性能，探讨了过氧化物用量对材料力学性能及凝胶含量的影响，以及炭黑、氧化锌、抗氧剂对材料性能的影响。结果表明，过氧化物交联聚乙烯的力学性能有一定的提高，随着DCP含量的增加，交联PE的凝胶含量提高，而随着凝胶含量的提高，交联PE的拉伸强度提高，断裂伸长率下降；炭黑对材料有一定的补强作用，氧化锌的加入有助于交联反应和拉伸强度的提高。     

垂直同心环形管内上升气液两相环状流含气率与压降预测

对垂直同心环形管内上升气液环状流的截面含气率及压降预测进行了研究.根据Kelessidis有关团状流向环状流转换的思路以及Wallis有关圆管内环状流积分分析的方法,考虑环形管的结构特征及环状流的流型特征,通过两相动力学理论建立了新的预测截面含气率及总压降的模型.将新模型及现有模型与实验数据的分析比较表明新模型对于总压降的预测效果较好.     

应用电导探针测定鼓泡塔内气泡参数

介绍了一种性能稳定的双头电导探针的制作工艺、测量原理。并用此电导探针测量了一定静液层高的带单个泡罩的鼓泡塔内气液两相流参数,包括局部气含率、界面浓度、当量直径等,并首次回归了局部气含率随空间位置、气体流量变化的关联式。     

Comparison of approaches to determine hydrogen consumption during catalytic hydrotreating of oil fractions

Different approaches to calculate the hydrogen consumption during hydrotreating of petroleum fractions are reviewed and discussed. Experimental information about the hydrotreating of various distillates (naphtha, light and heavy gasoils, atmospheric and vacuum residues) obtained in a bench-scale unit at typical operating conditions and commercial catalysts was used to determine the hydrogen consumption from global hydrogen balance and from the hydrogen balance in gas streams. The comparison of experimental hydrogen consumption calculated with the different approaches indicates that there is not a method that can predict hydrogen consumption with good accuracy. For quick calculation some correlations can be used, but the error can be as high as 15%. The common approach used in refineries, which does not take into account the dissolved hydrogen in the hydrotreated liquid, can give deviations up to 6% with respect to the experimental value. To account for this dissolved hydrogen into the balance all the correlations reported in the literature are suitable.     

大型下行式循环流化床反应器颗粒浓度分布研究

采用双光路光纤密度探头研究了内径418mm,高18米大型下行式循环流化床（其中下行床部分长度6．5m)反应器中的颗粒浓度分布，结果表明大直径下行床中颗粒浓度沿径向呈现中心均匀，近壁处存在高浓环形区的分布，这类似于小直径反应器中的结果，随着反应器直径的增加，颗粒浓度分布最大值的径向位置向边壁方向移动，即：当下行床放大时，中心颗粒浓度均匀分布区的面积占整个床层截面积的比例增大，在一种特殊设计的下行床边壁结构中测量了颗粒浓度沿径向的分布，实验结果说明边壁效应对下行床近壁区颗粒浓环的形成起到了重要作用，研究结果将有助于了解下行床反应的放大特性。     

Effect of the Solid Loading on a PFBC Cyclone with Pneumatic Extraction of Solids

This paper presents the effects of solid loading on the performance of a cyclone with pneumatic extraction of solids. The cyclone is a non‐conventional design, especially used for hot‐gas cleaning applications such as pressurized fluidized bed combustors (PFBC). A scaled‐down cold‐flow model was employed for the research. Experiments were conducted at 9–14 m/s inlet gas velocities, inlet solid loadings ranging from 30 to 230 g/kg gas, and bottom gas extraction percentages from 0.3 to 1.5%. Experimental results of pressure drop resistance coefficients and collection efficiency were compared with literature predictions. At PFBC operating conditions, cyclone geometry and solid concentration are the main parameters influencing cyclone pressure drop and collection efficiency. The vortex penetration in dipleg causes lower pressure drop values and higher collection efficiencies than predicted. These parameters can be suitably predicted for PFBC cyclones by introducing a modified penetration length in Muschelknautz's model [1]. For the present cyclone design, a new correlation of pressure drop, including the influence of solid loading, is proposed. A new method for detecting cyclone fouling, not previously addressed, is also presented, based on the evolution of the pressure drop resistance coefficient. An enhanced separation efficiency has been found, related to collection efficiency, which is especially important for particle sizes below 10 μm revealing agglomeration effects.     

铝塑复合管硅烷交联聚乙烯专用料的研究

研究了高密度聚乙烯（HDPE）／线性低密度聚乙烯（LLDPE）硅烷接枝交联体系。分析了过氧化二异丙苯（DCP），乙烯基三乙氧基硅烷（VTES），加工设备及工艺条件（温度，螺杆转速）对体系熔体流动速率（MFR）和凝胶含量的影响。并用Buss混炼设备制备出高流动性的铝塑复合管硅烷接枝交联PE专用料。     

基于1H NMR测定和基团贡献法预测石油馏分的热化学性质

测定了两种原油 2 0个石油馏分的¹H NMR谱和氢、碳元素含量等结构参数 ,以及馏分的燃烧焓、蒸发焓等热化学性质 .假设每个石油馏分仅由CH₃ 、CH₂ 、CH、ACH和C这 5种简单基团构成 ,基于¹H NMR测定和元素分析结果解出石油馏分平均分子结构中的基团数目 ,再用纯有机物的基团贡献法预测石油馏分的燃烧焓、蒸发焓 ,预测值与实验数据吻合良好