阴双层床在除盐系统的应用试验研究

双层床设备系统在联合应用弱型,强型树脂化学除盐工艺中具有较高的实用价值。本文简要论述了双层床在阳,阴离子交换系统的不同使用特点;着重研究了阴双层床使用中的问题和改进措施,并由实际统计结果证明了在采用新的两步进碱法再生工艺后,阴双层床的运行完全要以达到设计指标。     

离子交换的双室双层床技术

本文介绍了双室双层床的特点、设备结构、计算以及运行操作,并对此新技术作出了评价。     

三相流化阳离子交换—除CO2联合处理装置的试验研究

本文研究了一定操作条件下三相流化阳离子交换－除ＣＯ２联合处理装置内的液体轴向速度分布,讨论了水速,气速和固含率对液体轴向速度的影响,根据所选定的最佳工艺参数对三相流体阳离子交换－除ＣＯ２联合处理装置进行了性能研究,出水水质满足要求。     

强酸型阳离子交换器的再次交换利用

介绍在传统的弱,强阳床生产脱盐水的工艺中,强酸型离子交换树脂失效后实际变为Ｎａ型离子交换树脂,入口水改为生水,使Ｃａ＾２＋,Ｍｇ＾２＋与Ｎａ＾＋,Ｋ＾＋进行交换,从而可副产软化水。     

单元制离子交换器终点控制的方法

通过分析单元制离子交换器运行末期电导率的变化情况,可以判断交换器运行终点,采用电导率判断终点代替同时分析SiO2和电导率判断运行终点的方法,使单元制离子交换器终点控制更加方便、可靠,且可减少投资。     

离子交换树脂在玉米淀粉糖生产中的应用

利用离子交换树脂纯化和分离玉米淀粉糖在５０年代初得到了应用。按照已开发的技术,开发了玉米淀粉在酸（或）酶的作用下转化成糖浆。用碳和离子交换树脂处理,减少其颜色及灰分,生产出一种质量稳定的玉米淀粉糖液,或用做深加工工艺过程中的原料,了子交换过程除去灰分、蛋白南及色泽,可增加糖浆色泽的长期稳定性而不用加入二氧化硫,因成品中如有二氧化硫将对人体产生过敏反应,制糖及食品工业使用离子交换树脂供脱钙、除盐、脱     

前置式双流弱酸床的再实践

在除盐系统增设双流弱酸床的扩容改造中,由于改进了计算方法及运行中更新了常用的定量进酸再生方式,使改造后的运行实绩与设计计算结果较好吻合,系统周期工交容量由原强酸单床平均771mol/m~3增高到1960mol/m~3,弱酸阳床工交容量达3140.1mol/m~3。     

Heat transfer simulation in a raining packed bed exchanger

A model is presented that predicts the thermal performance of a raining packed bed heat exchanger (RPBE) from hydrodynamic data. The main feature of this gas-solids countercurrent heat exchanger is the presence of a packed zone which greatly enhances energy transfer between the two phases by slowing down the falling particles. The model based on the Ergun equation for evaluating an effective solids hold-up in the packed zone correctly predicts the fact that the efficiency passes by a maximum as the hot gas velocity increases. Experimental results obtained with sand particles of 205 μm mean dia. in a column filled with Pa11–15 rings agree reasonably well with the predicted ones.     

基于改进型吸附等温线模型的空气预纯化TSA双层床模拟

为了掌握空气中CO2和水蒸气在空分装置双层床变温吸附(TSA)纯化器中的动态吸附特性,通过LDF传质假设及非绝热假设,建立了一维二元稀组分系统的双层床TSA过程数学模型。一种改进型的多组分等温线模型用于描述水蒸气的Ⅱ型吸附等温线以及水蒸气和CO2混合物的吸附平衡关系。通过对比模拟结果与TSA纯化器的现场监控数据发现,基于改进型等温线模型的模拟结果与现场数据吻合良好。最后对多种工况下的TSA纯化器中的温度、浓度及吸附量床层分布和穿透曲线进行了数值模拟和分析。     

Coiled flow inverter as a heat exchanger

In the present work attempts are made to investigate the hydrodynamics and heat-transfer characteristics of a coiled flow inverter (CFI) as heat exchanger at the pilot plant scale. The experiments are carried out in counter-current mode operation with hot fluid in the tube side and cold fluid in the shell side. Experimental study is made over a range of Reynolds numbers from 1000 to 16,000 using water in the tube side of the heat exchanger. The shell side fluids used are either cooling water or ambient air. The coiled flow inverter is made up of coils and 90^° bends and inserted in a closed shell. The shell side is fitted with three types of baffles to provide high turbulence and avoid channeling in the shell side. The bulk mean temperatures at various downstream positions are reported for different flow rate on tube side, as well as the heat transfer efficiency of the heat exchanger is also reported. Pressure drop and overall heat-transfer coefficient is calculated at various tube and shell side process conditions. The outer and inner heat-transfer coefficients are determined using Wilson plot technique. The results show that at low Reynolds numbers, heat-transfer is 25% higher as compared to coiled tubes. At high Reynolds numbers, the configuration has less influence on heat transfer. New empirical correlations are developed for hydrodynamic and heat-transfer predictions in the coiled flow inverter.     

Gas—particle heat transfer in a crossflow moving packed bed heat exchanger

A programme of work on a moving packed bed heat exchanger, whereby a gas is blown vertically upwards through a horizontally moving packed bed of particles, is described in this paper. Such a device can be used for the process heating or cooling of particulate solids. In the work rigorous and simplified analyses to describe the process of gas—particle heat transfer in the system were developed and the application of these analyses demonstrated by a series of experiments on a small-scale unit.     

Simultaneous removal of cyanide and copper ions in a semi-fluidized ion exchanger bed

Simultaneous removal of cyanide and copper ions from electroplating wastewater was studied in a liquid-solid semi-fluidized ion exchanger bed. The diameter and the height of column are 20 mm and 600 mm, respectively. Strong-base anion exchange resin particles (Dowex 1X8-50) were contacted with synthetic solutions containing copper and cyanide ions. Cyanide and copper ions in the solution were analyzed by a cyanide electrode and ICP (inductively coupled plasma), respectively. The ion exchange equilibrium data of Cu⁺ removed as cyanide-copper complexes on Dowex 1X8-50 at 25 ‡C can be fitted with the Langmuir equation. Early leakage of cyanide from experimental loading profile data results in not only lower selectivity of free cyanide but also different selectivities of CN-Cu complexes due to the size and the structure of complexes. The optimum molar ratio (Q) between cyanide and copper ions is about 3 to obtain a reasonable removal rate of cyanide in this experiment.     

液固循环流化床换热器管束的固含率

在二维中试循环流化床中使用组合式固液分布器进行实验,考察下管箱表观液速,主分布器内径、主分布器下插深度,颗粒加入量和粒径对径向管束固含率的影响.结果表明:固含率随主分布器内径、颗粒加入量和下管箱表观液速的增加而增大,随粒径的增大而减小,随主分布器下插深度几乎没有变化;固含率不均匀度随颗粒粒径的增大而增大,随下管箱表观液速、颗粒加入量,主分布器下插深度增加而减小,但达到一定深度后,不均匀度不再随之减小,随主分布器内径几乎没有变化.在综合考虑各影响因素的基础上,提出计算固含率的经验公式,并用实验数据拟合了公式中的参数.     

水平管循环流化床换热器防垢试验研究

以硫酸钙为工质,在水平管循环流化床换热器装置内进行条件试验,研究水平流化床的防垢效果和传热性能.实验结果表明,水平管循环流化床换热器具有良好的防垢效果和传热性能.     

脱硅预热器流化床在线清垢方法研究

将无机非金属材质的球形惰性固体颗粒引入铝土矿溶出粗液预热脱硅系统中，研究液固循环流化床在线清垢方法，解决脱硅预热器硅渣结垢严重、清洗费用高、劳动强度大的等问题。结果表明：液固循环流化床能达到在线清除硅渣结垢的结果，并且在线清垢速率随操作流速及固体颗 料用量的增加而增大；当流速为2．0m/s，对于500mL，和700mL，固体颗粒用量的完全除垢时间分别为2h和1h。     

气液固循环流化床换热器中预分布器结构的优化

引言 气液固循环流化床换热器是将循环流化床与沸腾传热两项技术结合而开发出的一种新型高效传热和防、除垢设备.国内外众多学者对此设备进行了研究[1,2].然而,关于此换热系统正常运转的核心技术--颗粒分布技术的文献较少.荷兰的Klaren申请了专利[3],叶施仁等[4]设计了单层孔板式固液分布器,姜锋等[5]选取直径小于下管箱直径的多孔板作为固液分布器,但上述固液分布器的大规模工业应用未见相关报道.     

循环流化床换热器中液固二相流的数值模拟

在循环流化床换热器的流体中加入固体粒子,可以对边界层有扰动作用,加快换热器中的传质与传热.对流化床换热器中的液固二相进行数值模拟,分别讨论了固体粒子对液体动量方程、k-ε方程及能量方程的影响,在单液相方程的基础上进行修正,建立了相应的液固二相流控制方程,确定了物理模型及边界条件.利用FLUENT进行数值计算,分别讨论了...