应用开孔转盘塔进行液膜分离

本文通过无传质条件下油—水、乳化液膜—水体系开孔转盘塔连续操作试验,考察了塔型改变对x～n、u_0～n及n_γ的影响。通过乳化液膜一含酚水体系的传质试验,考察了传质对滞存率χ的影响和连续相pH值及两相密度差(△ρ)的变化对塔传质性能的影响。试验结果表明:开孔转盘塔的液液分散性能远远优于无孔转盘塔,盘上的小孔对经过小孔而上升的液滴有着良好的切割分散作用;除酚试验时,连续相的pH值及两相密度差(△ρ)对传质有影响,传质对滞存率x的影响也十分显著。     

应用多孔转盘的转盘塔进行液膜分离的初步研究

采用带多孔转盘的转盘塔作为液膜分离的连续操作装置,进行了流体力学和传质特性的初步研究.实验表明:开有小孔的转盘塔板具有良好的液液分散性能和传质性能,适用于液膜分离的连续操作.     

一种新型高粘性物料萃取设备

本文讨论了多种形式塔盘结构对粘度高达187～2426cP物料萃取效果的影响。对塔内径为142mm及500mm的萃取塔,分别对转盘、栅板塔盘、齿形塔盘、多孔转盘以及网格塔盘进行静态传质实验。结果说明,网格塔盘传质效果最好。此外,还对塔内径为152mm、高为2m的转盘塔和网格塔进行两相逆流传质实验并进行比较,证明新型网格塔传质效率可提高一倍以上。并获得网格塔传质单元高度与转速、流率、粘度及滞存率等各因素的关联式。     

开式涡轮转盘塔内传质及流体力学的研究

在开式涡轮转盘塔内进行了液—液—固三相体系的流体力学和传质实验,结果表明,固相的加入对传质性能有很大影响,同时得出不同传质方向时的特征速度关联式。     

液膜法处理焦化厂含酚废水的中试工艺与设备

本文扼要介绍乳状液膜处理太原焦化厂含酚废水所用的中试工艺与设备(处理废水能力为1.7t/d)。当废水中酚浓度为500—1000ppm时,经二级处理可下降到排放标准0.5ppm以下。作者提出采用锥孔转盘塔,它是在RDC基础上发展起来的另一种改型RDC,特别适用于低界面张力体系。实验结果表明:锥孔转盘塔能提高传质效率,可使传质单元高度降低25％。     

应用多孔转盘的转盘塔进行液膜分离的初步研究

采用带多孔转盘的转盘塔作为液膜分离的连续操作装置,进行了流体力学和传质特性的初步研究。实验表明:开有小孔的转盘塔板具有良好的液液分散性能和传质性能,适用于液膜分离的连续操作。     

开式涡轮转盘塔的液-液-固实验研究

<正> 一、前言 转盘塔(RDC)是工业上广泛应用的萃取塔设备之一。自从大约40年前RDC被用于石油工业以来,人们对它的性能进行了深入的实验研究,设计方法已日趋成熟、完善。据报道该塔可用于处理某些含固悬浮体系,因而有可能将其应用于浸取、浆式萃取、液—液—固复分解反应及LEACHEX过程(一种     

多锥孔转盘塔在液膜萃取中的应用

液膜分离技术是一项崭新的工艺。本文在探索分离设备转盘塔设计的基础上,通过改进塔内构件—采用了多锥孔转盘,提高了传质速率,避免了返混和液泛现象,使转盘塔分离效果得到了显著提高。通过二级处理,使含酚废水含酚量达到排放标准。     

新型转盘萃取塔在己内酰胺生产中的应用

探讨了转盘萃取塔在己内酰胺精制中萃取效率的影响因素,影响转盘萃取塔传质性能的主要因素是级间的轴向返混和沟流。介绍了新型转盘萃取塔的设计及其在70 kt/a己内酰胺精制装置中的工业应用效果。与原装置转盘萃取塔的运行情况比较,新型转盘萃取塔内的固定环平面增加了筛孔挡板,能有效抑制转盘萃取塔内的轴向返混,提高转盘萃取塔的传质效率。     

搅拌槽中液-液-固三相传质的实验研究

选择欧洲化学工程师协会(EFCE)推荐的典型液-液萃取体系正丁醇-丁二酸-水,加入不同粒径的玻璃珠构成液-液-固三相传质,以去离子水为连续相,正丁醇为分散相,溶质丁二酸从分散相向连续相传质. 利用电导率法测定液-液相传质系数,并考察了搅拌转速、固体质量百分含量、不同桨型(标准Rushton桨、上推式和下推式45°六折叶涡轮桨)、桨中心平面距槽底距离以及固体颗粒粒径对相间传质的影响. 结果表明,在高转速时,惰性固体粒子的存在强化液-液体系的传质. 随着惰性固体含量增大,液-液-固三相传质有一极大值. 粒径大于100 μm 的固体粒子对液-液体系传质系数影响很小. 三种桨中Rushton桨的对流传质效果最好.     

Hydrodynamics and mass transfer performance of rotating sieved disc contactors used for reversed micellar extraction of protein

The extraction of protein by continuous liquid-liquid extraction was investigated in a rotating disc contactor (RDC) and a rotating sieved disc contactor (RSDC) with and without stators. Hydrodynamics and mass transfer performance for reversed micellar extraction of lysozyme in RDC/RSDC I and RSDC II have been investigated. The dispersed phase holdup has increased with the increase of rotor speed. Pratt's equation was used for calculating the characteristic velocity. An inverse relation was observed between the characteristic velocity and rotor speed. The estimated overall mass transfer coefficient was increased by increasing the rotor speed. For an extraction column, the overall hydrodynamics and mass transfer performance can be judged by a volumetric utilization factor. At high rotor speeds, volumetric utilization factor for RSDCs is higher than that of RDC. The RSDC II has been successfully applied in reversed micellar extraction of protein.     

Continuous aqueous two-phase extraction of α-lactalbumin from whey in conventional rotating disc contactor

The differential partitioning of α-La to the PEG-rich phase and β-Lg to the salt-rich phase was studied in the continuous extractor, rotating disc contactor (RDC), using polyethylene glycol (PEG) 1000–trisodium citrate system. The performance of the extractor was evaluated in terms of holdup, mass transfer coefficient, extraction efficiency, and recovery by studying the operating variables such as phase velocities and rotor speed. The process conditions for the maximum dispersed phase mass transfer coefficient and recovery of α-La was also obtained and reported.     

新型转盘萃取塔研究开发与工业应用

采用激光多普勒测速仪(LDV)和计算流体力学(CFD)软件,对转盘萃取塔(RDC)内的单相流流场进行了测量和模拟。发现塔内存在沟流和级间的旋涡流动,级间返混严重,为此发明了一种装有级间转动挡板的新型转盘萃取塔(NRDC)。NRDC与传统的RDC的区别在于安装了设计独特的转动挡板。这些转动挡板安装在2个转盘之间,固定在转动轴上,并与固定环处于同一水平面。LDV测量和CFD模拟结果发现,NRDC可有效抑制沟流和级间旋涡流动。传质实验和流体力学表明,NRDC的传质效率比RDC高20%—40%,而液泛速度大致相当。成功地将NRDC用于引进RDC的扩能改造和新塔的设计中。     

HYDRODYNAMICS AND AXIAL MIXING OF LIQUIDSOLID SYSTEM IN OPEN TURBINE ROTATING DISC CONTACTOR

The open turbine rotating disc contactor (OTRDC) has been installed simply by adding three narrow strips to the lower surface of each rotating disc in the rotating disc contactor (RDC), so it can be used for the system with high solid particle content. Hydrodynamics and axial mixing have been investigated in a 0.152m diameter OTRDC of different compartment height for the system of tap water and quartz particles. A model has been developed to describe the flow of liquid and solid phases. The solid phase holdup can be calculated satisfactorily according to the model equations. Axial mixing data have been treated by the backflow model and the correlations for predicting backflow ratios of liquid and solid phases in OTRDC have been presented.     

HYDRODYNAMICS OF LIQUID-LIQUID-SOLID SYSTEM IN OPEN TURBINE ROTATING DISC CONTACTOR

A number of experiments regarding hydrodynamics have been carried out in the open turbinerotating disc contactor using quartz particles as solid phase,tap water and kerosene as liquid phase.Flooding phenomenon has been observed.The variables studied include the rotor speed,compartment heigh,stator ring opening,column diameter and the superficial velocity of eachphase Correlations for predicting the solid phase holdup and characteristic velocity have been devel-oped.In comparison with liquid-liquid system,the presence of solid particles will result in higherdispersed phase holdup but lower characteristic velocity and total throughput.     

Dispersed-phase holdup and mass transfer in a rotating disc contactor with perforated skirts

Dispersed-phase holdup and extraction efficiency were measured in a pilot-plant scale rotating disc contactor (RDC) with perforated skirts (RDCS) with kerosene-o-cresol-water system. The data for the RDCS were examined using the data in this work and the available correlations proposed for the plain RDC. A comparison between the data measured in the RDCS and those in the RDC indicated that the RDCS has rather better extraction efficiency compared with the RDC.     

A NEWLY DEVELOPED LIQUID-LIQUID EXTRACTION COLUMN——The Open Turbine Rotating Disc Contactor(OTRDC)

The experimental study on hydrodynamics,axial mixing and mass transfer has been carried out in anewly developed liquid-liquid contactor,the open turbine rotating disc contactor(OTRDC).It has been foundthat the OTRDC is possible to be operated with higher hold-up of dispersed phase,larger interface and hencehigher efficiency of mass transfer comparing with the ordinary RDC.In correlating axial mixing data,a combinedmodel has been used in which both forward mixing due to the drop size distribution and backmixingof droplets are taken into account.The RTD curves of dispersed phase predicted by the model were fit wellwith the experimental data.The comparison of the experimental mass transfer data with thosc predicted by theaxial mixing model and theoretical single drop models shown they are in good agreement.     

Hydrodynamics,axial mixing and mass transfer in open turbine rotating disc contactor (OTRDC)

An experimental study of hydrodynamics, axial mixing and mass transfer has been carried out in a newly developed liquid-liquid extraction contactor, namely the open turbine rotating disc contactor (OTRDC). It has been established that the OTRDC can be operated with larger holdups of the dispersed phase, larger interfaces and, hence, more efficient mass transfer than the conventional RDC. In correlating axial mixing data, a combined model has been applied in which both the forward mixing due to drop size distribution and the backmixing of droplets are taken into account. The RTD curves of dispersed phase predicted by the model agree well with the experimental data. Comparison of experimental mass transfer data with those predicted by the proposed axial mixing model and the theoretical single drop model shows that they are in good agreement.     

Liquid—liquid extraction column (rotating disc contactor)—model parameters from drop size distribution and solute concentration measurements

The practical application of an extraction column model which takes into account the influence of drop-size distribution (i.e. the ‘forward mixing’ model) is brought forward by the generation, from experimental data, of values of the mass transfer and axial dispersion coefficients required by the model. Values of these coefficients were generated from drop-size distribution and solute concentration profile measurements in a 22 cm diam. rotating disc contactor. The use of the Handlos-Baron drop mass transfer model is justified. The resulting continuous phase transfer coefficients were found to be dependent only on disc speed. Continuous phase axial dispersion coefficients were much higher than tracer-correlation predicted values at higher flows, and larger drop sizes. An explanation for this is presented.