Novel Gas-Liquid-Solid Reactors

Multiphase reactors involving gas, liquid, and solid phases have several important applications in the chemical industry, particularly in catalytic processes. Some of the well-known examples are: hydrogenation and oxidation of organic compounds, hydro-processing coal-derived and petroleum oils, Fischer-Tropsch synthesis, and methanation reactions. Due to the presence of three phases, the problem of reactor design is often important to achieve effective mass and heat transfer as well as a mixing pattern favorable to the particular process. The reactors are mainly of two types: (a) solid catalyst is suspended either by mechanical agitation or gas-induced agitation and (b) solid catalyst is in a fixed bed with concurrent or countercurrent feed of gas and liquid re-actants. The reactor types conventionally used in industry are: (a) mechanically agitated or bubble column slurry reactors and (b) trickle-bed or packed-bed bubble reactor. The various design and modeling aspects of these reactors have been reviewed by Satterfield [1], Chaudhari and Ramachandran [2], Shah [3,4], Ramachandran and Chaudhari [5], Shah et al. [6], and Herskowitz and Smith [7]. In several industrial processes these reactor designs are modified to achieve a certain specific objective, such as better heat or mass transfer, higher catalyst efficiency, better reactor performance and selectivity, etc. Similarly, specially designed reactors are often used for laboratory kinetic studies or to understand a certain phenomenon. Thus, novel multiphase reactors are becoming important from both academic and industrial viewpoints. Some of the recently introduced novel gas-liquid-solid reactor types are: (a) loop recycle slurry reactors, (b) basket-type reactors, (c) ebullated-bed reactors, (d) internal or external recycle reactors, (e) multistage slurry or packed-bed reactors, (f) column reactors with sieve trays or multiple agitators, (g) gas-induced agitated reactors, and (h) horizontal-packed-bed reactors. are being used in several new commercial processes, and various design aspects, such as hydrodynamics and mass and heat transfer, have been the subject of investigations in the last few years. However, no attempt to review the scattered information on these novel gas-liquid-solid reactors has been made. Therefore, the main objective of this paper is to review important developments in novel gas-liquid-solid reactors. For each type of reactor, advantages, disadvantages, and applications are discussed. Further, the status of information on hydrodynamics and mass transfer parameters and scale-up considerations is reviewed. These novel reactor designs are being used in several new commercial processes, and various design aspects, such as hydrodynamics and mass and heat transfer, have been the subject of investigations in the last few years. However, no attempt to review the scattered information on these novel gas-liquid-solid reactors has been made. Therefore, the main objective of this paper is to review important developments in novel gas-liquid-solid reactors. For each type of reactor, advantages, disadvantages, and applications are discussed. Further, the status of information on hydrodynamics and mass transfer parameters and scale-up considerations is reviewed.     

精细化工中的气-液-固加氢反应器

气-液-固加氢反应器在精细化工中有广泛的应用,本文介绍了气-液-固加氢反应器的混合和操作,并为气-液-固加氢反应器的设计和选择提出-些参考.     

气液固三相流化床反应器测试技术

在简述已有三相流化床测试技术的基础上,着重对近年来开发的测试新技术的基本原理及优缺点进行了分析,包括光纤探头技术、超声探头技术、放射颗粒跟踪技术、X射线颗粒跟踪测试技术、颗粒图像测速技术、电容层析成像技术、激光多普勒测速技术和相多普勒测速技术等,同时,展望了三相流化床测试技术的新方向.     

气液固三相床中合成甲醇与二甲醚

叙述了气液固三相催化反应技术的主要特点和应用领域，并着重介绍了三相床合成甲醇和二甲醚的试验研究内容和成果。     

气-液-固三相流化床

本文较系统地讨论了气-液-固三相流化床的研究现状,包括流动城、相含率、相闻质量传递、各相混合、热量传递特性和气泡行为等,同时指出了这一领域今后可能的发展趋势。     

下行床弧面锥体气固分离装置的分离效率实验

以FCC颗粒为物料，实验研究了在气固并流下行循环流化床(f=37 mm, H=5 m)中，气固两相分离装置的结构、颗粒循环量、表观操作气速对分离器气固分离效率的影响. 结果表明，在气固并流下行系统中，采用弧面锥体气固分离装置，内加导流板，在气速为1~5 m/s，颗粒循环速率20~90 kg/(m2.s)条件下，可使气固分离效率达到99%以上，压力损失小于500 Pa.     

气体提升搅拌反应器的研究

本文对气体提升搅拌反应器（Pachuca tank）的性能,进行多方面的实验研究:建立了反应器内循环量的计算方法;根据对固体颗粒作用力的分析,研究了反应器内固体颗粒的临界沉淀速度;由能量平衡的概念出发,通过实验,建立了反应器堵塞的临界速度关系式。此外,还对反应器结构作了讨论,可供设计和操作时参考。     

Modeling and Simulation of Gas-Liquid-Solid Three-Phase Fluidization

A closed Eulerian/Eulerian/Lagrangian mathematical model (E/E/L model) for simulating the local flow characteristics of gas-liquid-solid three-phase fluidization systems was established by combining the Two Fluid Model (TFM) and the Distinct Element Method (DEM). This model was based on the fundamental equations of fluid mechanics. The motion of particles was described in the Lagrangian coordinates, while the gas phase and the liquid phase were dealt with in the Eulerian coordinates. Based on IPSA and PSIC solution techniques, the program of simulating gas-liquid-solid local flow was achieved. The predicted results of local gas holdup and local solid holdup as well as local axial liquid velocity agree with the corresponding experimental data of a gas-liquid-solid three-phase fluidized bed, and the applicability and reliability of this proposed model were validated.     

微反应器内硝基苯气-液-固三相催化加氢反应

考察了催化剂壁载方式、涂层载体和Pd负载量对微通道内的硝基苯气-液-固三相催化加氢反应的影响以及其并行放大效应.结果表明,与溶胶-凝胶法相比,浸渍法制备的催化剂涂层性能较好,其转化率、选择性分别达到89.2％和93.8％;采用强酸性、大比表面积的载体有利于反应性能的提高;活性组分Pd负载量为2.00 mg,催化剂活性较...     

筛板塔气液固三相塔板效率的实验

在冷模筛板塔上进行了气液固三相流体塔板效率的实验，得到在不同固含率下塔板气液相流量与塔板效率的变化关系. 结果表明，随着液相流量的增加，塔板效率降低；随着固含率的增加，塔板效率先增加然后减少. 并验证了气液塔板效率的计算方法可用于气液固三相塔板效率.     

气—液—固三相磁性流化床混沌特性研究

运用确定性混沌分析技术,研究了气－液＝固三相磁性流化床系统压力波动时间序列的混沌特性。在给定表观气、液速下,非一特征参数如最大李雅谱诺夫指数和Ｋ熵都大于零,并且随磁场强度的增加而减小,表明该系统具有混沌行为：磁场作用使气－液－因三相流动更趋有序。研究还表明,气－液－固三相磁性流化床的三个流区（散流区、链流区及磁聚区）变化可由混沌特征参数值的变化来体现。     

Novel and Ideal Zirconium-Based Dense Membrane Reactors for Partial Oxidation of Methane to Syngas

A novel and ideal dense catalytic membrane reactor for the reaction of partial oxidation of methane to syngas (POM) was constructed from the stable mixed conducting perovskite material of BaCo_0.4Fe_0.4Zr_0.2O_3– and the catalyst of LiLaNiO/-Al₂O₃. The POM reaction was performed successfully. Not only was a short induction period of 2 h obtained, but also a high catalytic performance of 96–98% CH₄ conversion, 98–99% CO selectivity and an oxygen permeation flux of 5.4–5.8 mlcm^–2min^–1 (1.9–2.0 molm^–2S^–1Pa^–1) at 850°C were achieved. Moreover, the reaction has been steadily carried out for more than 2200 h, and no interaction between the membrane material and the catalyst took place.     

发泡剂ADC生成过程动力学分析

在玻璃搅拌反应器中进行了固体联二脲与氯气液相氧化反应生成发泡剂 ADC过程的传质与动力学实验, 提出了基于双膜理论的数学模型,以描述这一反应系统所涉及的气液和固液传质、固体溶解以及溶解物在液相中发生瞬间反应,特别是随反应进行固体反应物粒径变小导致固液传质速率减小的复杂过程. 模型能很好地描述实验结果. 依据模型估测的气液与固液传质系数值比较表明,气相反应物氯气的溶解传质过程是影响整个过程速率的主要控制步骤.     

气液固三相流动沸腾传热与抗垢性能的研究

在流动沸腾的液体中引入少量惰性气体与固体颗粒,使之成为气液固三相流态化沸腾过程,对其传热性能与抗垢性能进行实验研究。结果表明,引入惰气与流态化固体颗粒,可使传热显著强化,表现出明显的防垢抗垢效果,且具有一定的线清洗作用。     

气-液-固三相逆流化床动力学研究

在内径0.152 m,高2.5 m的气-液-固三相逆流化床中系统研究了动力学特性。获得了气体和液体速度及聚乙烯和聚丙烯颗粒密度对各相含率和最小液体流化速度的影响规律。研究发现随着气体速度的增加,液体最小流化速度降低;随着气体或液体速度增加,气体、液体和固体含率均增加。     

筛板塔气流固三相塔板效率的实验

在冷模筛板塔上进行了气流固三相流体塔板效率的实验，得到在不同固含率下塔板气流相流量与塔板效率的变化关系。结果表明，随着液相流量的增加，塔板效率降低，随着固含率的增加，塔板效率先增加然后减少，并验证了气液塔板效率的计算方法可用于气流固三相塔板效率。     

A Novel Approach for the Determination of Mechanical Stresses in Gas‐Liquid Reactors

A new method for the determination of mechanical stresses in two‐phase reactors is described. The time‐dependent disintegration kinetics of a clay‐floc system are measured with a laser scanning microscope. By describing the flocs employing fractal geometry and by transforming the disintegration kinetics according to a multifractal‐approach for turbulent flow fields, effective stresses can be calculated for bubble columns in two‐phase operation mode by comparison to the mechanical stress in a turbulent single‐phase couette flow. Results are given for stresses measured in a bubble column at different operating conditions.     

气液固三相并流系统流型的混沌识别

运用确定性混沌分析技术，研究了气液固三相并流系统散式鼓泡流、聚式鼓泡流、柱塞流、泡沫流及环状流压力波动信号的混沌动力学行为。结果表明，吸引子可以用来表征气液固三相并流系统的动力学行为，混沌特征参数相关维D2和K熵可以用来定量识别以上五种流型。以混沌定量识别为基础，给出了三相并流系统的流型图。