气升式陶瓷膜-生物反应器渗透通量的实验研究

为了降低陶瓷膜-生物反应器的能耗、同时提高膜的渗透通量，本文将气升式外循环引入膜-生物反应器的设计。实验条件下，搭建了气升式陶瓷膜-生物反应器装置，研究了导气管直径、气升位置、气速、气体性质等循环条件对渗透通量的影响；并在相同条件下与液体不循环的过滤相比较，证明采用气升循环可以较大提高膜的渗透通量。     

气升式环流反应器研究与应用进展

综述了气升式反应器性能的主要影响因素研究及其最新的应用，提出今后研究工作的主攻方向，并介绍了最近超声气升式反应器及光气升式反应器的研究结果。     

盐藻在气升式光生物反应器中的光自养培养

在气升式光生物反应器中进行了盐藻培养特性的研究，确定了盐藻在2.5 L气升式光生物反应器中培养的适宜条件为：温度30℃，光强1.6 mW/cm2，盐浓度16%，通气量20 ml/min. 扩大到20 L反应器培养盐藻生长良好. 采用气升式光反应器培养盐藻生长快，周期短，4~7 d后即可进入稳定期；最终细胞密度大，最大为1.6?106 cells/ml；藻液中胡萝卜素含量高，最高含量32 mg/L.实验表明气升式光生物反应器适合于盐藻的培养.     

内循环气升式生物流化床水力学与传质特性研究

通过测定内循环气升式生物流化床的停留时间分布与溶解氧浓度，分析流化床内有效工作体积与氧传质系数的变化，以此研究其水力学与传质特性。结果表明，随着载体含量和气流量的增大，流化床内有效工作体积明显减小；氧传质系数则随着载体含量的增加先增后减，随着气流量和液流量的增大而增大。在本实验范围内，得出最适宜操作参数为载体含量为6％左右、气流量为180～240L／h之间、液流量为90L／h。     

美味牛肝菌在气升式反应器中的特性试验

以 １．５Ｌ外循环气升式反应器（ＯＡＬＲ）进行美味牛肝菌（Ｂ． ｅｄｕｌｉｓ）的深层培养试验,其最适通风量为 ０～２４ｈ, ０ ３ｖｖｍ;２４～７２ｈ, ０． ４ｖｖｍ;７２～１２０ｈ, ０． ５ｖｖｍ。培养时间较摇瓶培养大约可提前 １２ｈ,菌丝干重可达 ２６． ３ｇ／Ｌ。     

HYDRODYNAMIC STUDIES ON LOOP REACTORS(Ⅱ) AIRLIFT LOOP REACTORS

Hydrodynamics of airlift loop reactors was studied in detail experimentally andtheoretically.An internal airlift loop reactor was designed and set up for this study.An instru-mentation system based on the electrochemical method was adapted to measure local gas holdup andliquid velocity.A two-dimensional two-fluid model based on the first principles was established andimplemented to model the flow in airlift loop reactors.A corrected turbulent model was incorporatedin the simulation.The shear rate,shear stress and energy dissipation are evaluated from the flowfield.The numerically predicted results and experimental data obtained from this work as well as thesereported in literature are analyzed and compared.     

Gas dispersion in air‐lift reactors: Contribution of the turbulent part of the added mass force

Gas dispersion in an airlift reactor focusing on the closure law on turbulent contribution of added mass is presented. A data bank for bubbly flow in an airlift reactor is presented. The liquid velocity is measured by hot film anemometry and gas fraction and velocity are measured with an optical probe. The sensitivity of numerical simulations of gas dispersion to the modeling of turbulent contribution of added mass is shown. Without the turbulent contribution, the bubbles move toward the region where the turbulence is high and the pressure is low. When the turbulent contribution is introduced, the bubble migration towards the low pressure region is counter‐balanced and the void fraction profile is significantly modified. The modeling of the turbulent contribution of added mass is expressed in terms of the turbulent correlations in the gas phase, u_Gi^′u_Gj^′ , that can be related to the Reynolds stress in the liquid phase, u_i^′u_j^′ . © 2011 American Institute of Chemical Engineers AIChE J, 2011     

导流管结构对三相环流反应器相含率的影响

本文阐述了分别在三套内环流反应器内,采用空气—水—石英砂三相物系,导流管外径依次取为75mm和60mm,导流管底隙高度为17mm和30mm.研究了在一定的固相质量分数及初始静液高度下,导流管内局部相含率与表观气速的随动关系以及在固定操作气速下相含率在导流管内的轴向分布情况.经装置间平行比对得出:采用75mm外径的导流管...     

三相气升式反应器的CFD模拟及分析

为了研究硅酮母粒对气升式生物反应器流态性能的影响,以气含率和液相流速为评估指标,采用欧拉三相流模型对反应器进行计算流体力学模拟和参数优化。模拟结果表明,反应器气含率和液相流速与进气流速呈正相关,进气量为3 L/min时反应器上升区和下降区气含率分别为17.1%和9.1%,液相流速分别为17.5 cm/s和24.6 cm/s,与实测值误差小于5%,证明了模型的合理性和适用性;硅酮母粒含量(VS)由5%(φ)增至15%(φ)的过程中,反应器中气体分散程度和液相流速整体上有所降低,VS=10%(φ)时反应器内既能实现完全流化又能维持较高的气含率和液相流速;硅酮母粒的粒径与颗粒孔隙率影响三相间的能量传递,最适粒径为1.0 mm,最佳孔隙率为70%。     

气力泵疏浚特性研究

采用与实际清淤相似的槽底供沙方式,以普通河沙作为实验颗粒,搭建气力泵疏浚池,研究了山塘水库气力泵疏浚特性。结果表明,随气体表观流速增加,气力提升系统性能呈先增加后减小的趋势; 增加浸入率,系统性能峰值点对应的气体表观流速变小; 同一浸入率下,增大气举头埋入沙层的深度,气力泵提升性能显著增加。研究成果可为山塘水库气力泵疏浚提供理论及实践指导。