氧氯化反应器O_2/HCl进料分布器的腐蚀原因及措施

介绍氧氯化反应器O_2/HCl进料分布器的结构和腐蚀情况,找出分布器腐蚀的主要原因,采取有效措施,减轻分布器的腐蚀,延长氧氯化反应器的运行周期,改善反应效果,降低催化剂消耗,减轻环境污染。     

Gas Sparger Orifice Sizes and Solid Particle Characteristics in a Bubble Column – Relative Effect on Hydrodynamics and Mass Transfer

The relative effects of the size of gas sparger orifices and properties of solid particles on gas‐liquid mass transfer are not yet fully understood. Here, the impact of sparger orifice sizes, solid particle shapes, and their loading amounts in a bubble column reactor on the absorption of oxygen in tap water was investigated. Their influence on the mass transfer coefficient and bubble hydrodynamic parameters was evaluated. The results show that the addition of solid particles can have both positive and negative effects on hydrodynamics and mass transfer, depending on the orifice size of the gas sparger. The introduction of ring‐shaped solid particles can improve the mass transfer rate by up to 28 % without requiring any significant additional power.     

三相浅层鼓泡塔颗粒悬浮特性

研究了F383 mm的浅层鼓泡塔内高径比(H/DT)、气体分布器、固体浓度(Cs)对气含率和临界悬浮气速(Ugc)的影响. 结果表明,当H/DT<1.5时,随H/DT增大,气含率增大,而Ugc明显下降;当H/DT>1.5时,气含率减小,Ugc变化不大,优化的H/DT约为1.5. 采用四管管式气体分布器,当环径比(d/DT)为0.4时,Ugc最小. 气含率随Cs增大而减小,Cs超过15%(j)时,Ugc随Cs变化不大. 最后,推导得到Ugc的经验关联式,可为工业反应器提供一定指导.     

气泡发生器的流体动力学性能研究

气泡发生器作为浮选柱的核心部件,一直是浮选柱的研究重点。针对空气直接喷射式气泡发生器结构特点,分析了气泡发生器气体喷射出流的流体动力学模型,通过试验室和工业型浮选柱的清水气泡发生试验,修正了气泡喷射出流理论计算公式,对工业型浮选柱的大型化研制提供一定的理论依据。     

Coalescence during bubble formation at two neighbouring pores: An experimental study in microscopic scale

This work studies the effect of the liquid properties and the operating conditions on the interactions between under-formation bubbles in a cell equipped with two adjacent micro-tubes (i.d. ) for the gas injection, placed 210, 700 and apart. This set-up simulates, though in a simplified manner, the operation of the porous sparger in a bubble column, and it is used to study the bubble interactions observed on the sparger surface. Various liquids covering a wide range of surface tension and viscosity values are employed, while the gas phase is atmospheric air. A fast video recording technique is used both for the visual observations of the phenomena occurring onto the tubes and for the bubble size measurements. The experiments reveal that the interactions between under-formation bubbles as well as the coalescence time depend strongly on the liquid properties, the distance between the tubes and the gas flow rate. Two correlations, which can be found helpful for the bubble column design, have also been formulated and are in good agreement with the available experimental data.     

外环流反应器的气含率及循环液速

研究了气体分布器的形式、体系的聚并特性及静液面高度对外环流反应器的气含率和环流液速的影响。实验结果显示,对于空气－１％乙醇体系（非聚并体系）,气体分布器的形式对外环流反应器的气含率及环流液速有显著的影响;在相同的操作条件下,空气－１％乙醇体系（非聚并体系）的气含率及环流液速明显高于空气－水体系（聚并体系）。静液面高度对下降区的气含率有较大影响。     

Effects of sparger height and orifice orientation on solids dispersion in a slurry bubble column

The effects of gas distributor height and the orientation of its orifices are investigated on solids dispersion and gas holdup profiles in a three-phase slurry bubble column. The height of the distributor was varied to cover locations from near column bottom to above the settled solids bed height. The orifice orientations were changed from upward facing to downwards facing directions. The measurements were conducted in a Plexiglas column of 0.15 m ID and 2.5 m height. The gas phase was oil-free compressed air while tap water was used as liquid phase. Glass beads with an average particle diameter of 35 μm and density of 2450 kg/m³ constituted the solid phase. The settled bed height was about 0.4 m which provided an average slurry concentration of about 15% (v/v) when all solids were dispersed. Both axial and column average phase holdups were measured. Effects of sparger location, gas jets formation and liquid circulation patterns on gas holdups and solids dispersion are analyzed. Empirical correlations are developed to relate sparger location to solids dispersion as a function of gas velocity. Optimum sparger height and orifice orientation is proposed based on the measurement of this study.     

BGRIMM浮选柱技术的发展

评述了北京矿冶研究总院近50年来BGRIMM浮选柱技术的发展概况,着重分析了几种技术上比较成熟的BGRIMM浮选柱,特别对最近10年研制成功的浮选柱作了详细介绍,包括KYZ-A型顺流喷射浮选柱、KYZ-J型机械搅拌浮选柱、KYZ-E型浮选柱、KYZ-B型浮选柱和磁浮选柱等的工作原理、结构特点和应用情况,证明BGRIMM浮选柱在技术和应用上始终处于国内领先水平。     

气流-压力复合式雾化器

介绍了气流 压力复合式雾化器的结构、雾化机理，并以蒸汽为雾化动力，测试了气液比、气体压力对雾滴直径的影响。     

The influence of gas inlet design on gas hold-up values for water and various solutions in a loop-type air-lift fermenter

Gas hold-up was measured in an external loop air-lift fermenter for air in water, in sodium chloride and sodium sulphate solutions (concentrations between 0.025 and 1.0 kmol m⁻³), in glucose solutions (0.025 to 0.25 kmol m⁻³), sodium carboxymethyl cellulose (CMC) solutions (0.1, 0.2 and 0.5 mass %) and in suspensions of cellulose powder in water. Gas superficial velocities were up to 0.03ms⁻¹. Two types of gas spargers were used: one had six holes each of 1.6mm diameter, the other was of porous metal, which produced very small bubbles. Porous metal spargers with different diameters were also used, to alter the fraction of the cross-sectional area of the riser which was aerated (the ‘fractional aerated area’). The use of dimensionless gas velocities, obtained by dividing the superficial gas velocities by a characteristic velocity for each of the non-Newtonian liquids and solid suspensions, made possible a general correlation between gas hold-up, dimensionless gas velocity and the fractional aerated area, in bubbly flow conditions. The characteristic velocities for the electrolyte solutions could be related to the concentrations of the electrolytes. No general correlation could be obtained for gas slug-flow conditions, although theoretically-based relationships represent the results for each liquid. Gas slug-flow was observed for the non-Newtonian CMC solutions for most of the gas rates used at the lower concentrations; only at the highest concentration was bubbly flow found over a wide range of gas rates.