碳化工段

多降液管筛板塔[以下简称M.D.塔],是最近用于小化肥厂低压水洗的一种新塔型。此塔是在塔板上设置多条降液管,相邻两塔板的降液管又互相垂直,降液管悬挂于气相空间,降液管底部开有液流孔,液流从这些液流孔降至下一块塔板。与填料塔、单溢流筛板塔比较,M.D.塔喷淋密度较大,见表Ⅳ—1。     

国内化学工程文献摘要

77015多降液管筛板塔试验报告——浙江化工学院化工原理教研组,浙江化工,[1],1～13 (1976)。 本文对多降液管筛板塔塔板的流体力学、效率和降液管的流体力学等进行了试验,认为一般指标与其它塔型相差不多,处理的液量可比其它塔型大,对于L/V不大的情况,只要操作处于自封范围内应该是没有问题的。     

分散降液筛板塔传质性能

在筛板塔的基础上,研发了一种新型板式塔--分散降液筛板塔,将传统筛板塔的弓形降液管改为均布于塔板筛孔间的多降液管结构,使整个塔板面成为均匀降液和受液的传质区,并新增淋降和喷溅传质区,在全塔空间内实现立体、连续的微分接触式气液传质过程,另外,塔板之间可以加装填料来强化传质,或装填催化剂以促进伴随化学反应的传质过程。以“氧气-空气-水”为体系,初步研究了分散降液筛板的传质性能及其影响因素,并与传统筛板进行比较,结果表明:分散降液筛板气液分布均匀,接触充分,在同等条件下传质效率比传统筛板提高了8.4%~9.7%。     

多降液管筛板塔试验报告

在“教育必须为无产阶级政治服务,必须同生产劳动相结合”的光辉思想指引下,我们接受了化肥生产技术改造的任务,对水洗塔进行技术革新。我们本着“洋为中用”的精神,把具有显著优点的多降液管筛板塔(简称 MD 筛板塔),应用于我国的生产实践。MD 筛板塔的结构已在资料作了介绍。其最大特点是塔板上设置多条降液管,相邻两板的降液管又互相垂直,而且降液管悬挂于气相空间,降液管的底部开有液流孔,这种形式     

水洗筛板塔设计中的讨论

结合工作实践,阐述对大流量的水洗筛板塔液采用双溢流,无溢流堰的结构可以避免液泛,稳定操作,此类塔采用筛板塔比填料更经济,对大液量筛板塔设计有一定的参考价值。     

降液管长度对分散降液筛板性能的影响

探讨了分散降液筛板塔的降液管,通过计算分析设置了降液管的管径和长度,以"氧气-空气-水"为体系,研究了降液管长度对分散降液筛板的流体力学性能和传质性能的影响,结果表明降液管长度对分散降液筛板的性能具有重要的影响,且降液管长度为20mm的分散降液筛板综合性能较好。     

DJ型碳丙脱碳和热钾碱脱碳的扩能设计与应用

合成氨生产中常采用碳丙或热钾碱脱除合成气中的二氧化碳，它们的共性是塔内液体流率都比较大，气液流动参数都高达2以上，都属于加压下的高液气比操作。对于板式塔，在扩能改造中往往是塔板的降液管成为瓶颈，易发生降液管液泛现象。DJ塔板具有多根矩形降液管，溢流周边比常规塔板长2－5倍，可通过更大的液量，已在脱塔扩能设计中获得成功的应用。     

多降液管筛板塔鉴定会报道

浙江省石化局于一九七八年三月二十三日至二十五日在浙江省良渚化肥厂召开了“多降液管筛板塔鉴定会”。 会上由浙江化工学院作了关于多降液管筛板塔的研究及其在生产上应用的总结报告,以及良渚化肥厂、山东栖霞化肥厂、青江化肥厂、平湖化肥厂、新乡市化肥厂、淮南化肥厂等     

基于气-液传质强化的湿法烟气脱硫CFD模拟研究

针对燃煤电厂烟气脱硫过程中,高硫煤燃烧产生的高含硫烟气高效脱硫难题,通过计算流体力学(CFD)开展了钙法烟气SO₂高效脱除研究,提出了基于塔内筛板构件及喷淋系统优化的多手段耦合增效方法。建立了宏观脱硫塔尺度下涵盖喷淋吸收-筛板鼓泡吸收的SO₂多形式吸收脱除耦合模型,获得了浆液下落过程中的pH及SO₂吸收速率变化规律,并研究了湍流构件对脱硫塔内的气液混合流动、相内相间传质、浆液内部化学反应等过程的影响机制。探究了筛板对于脱硫塔脱除效率的强化机制,并进一步开展了筛板布置位置优化设计研究。同时,针对脱硫塔喷淋系统开展了优化设计研究,通过对比研究获得了喷淋系统优化后布置方案。基于所提出的脱硫塔多手段耦合增效方法,研究了包括液气比、浆液粒径及入口烟气SO₂浓度等不同参数影响下的脱硫塔SO₂脱除性能,发现通过塔内筛板构件及喷淋系统优化多手段协同增效后,可实现不同工况下脱硫塔SO₂脱除效率提升3%～8%。     

新型多降液管塔板的流体力学性能及其流场CFD模拟

开发了一种流场均匀且液相处理能力大的新型多降液管塔板。本文以水和空气为介质，在内径1219mm的有机玻璃塔内，研究了新型多降液管塔板的流体力学性能。结果表明，在相同气液负荷下，相较于弓形降液管塔板，新型多降液管塔板具有湿板压降低、雾沫夹带量小和漏液少等优点。同时新型多降液管塔板继承了多降液管（MD）塔板液相负荷高的特点，在空塔动能因子2.4(m/s)·(kg/m³)^0.5的条件下，全塔喷淋密度仍可高达80m³/(m²·h)。对塔板上液相流场的流体流动特性进行了计算流体力学（CFD）分析，并将模拟结果与MD塔板进行对比。结果表明，新型多降液管塔板降液管的结构和排布方式使得塔板上液体流动更加均匀，预期可以获得更高的塔板效率。     

Structured Packings in Liquid-Liquid Extraction

Abstract

Extractors equipped with structured packing are becoming more important in the chemical process industries. These devices provide high mass transfer efficiency and capacity relative to random packings and sieve trays. At the present time, many sieve tray extractors are being retrofitted with structured packings to enhance mass transfer efficiency and capacity. This paper will present a comparison of the performance of structured packing with sieve trays, some background on the commercial development of structured packings, and fundamental models required to design a liquid/liquid extractor equipped with structured packing.     

Performance of Spray,Sieve Tray,and Packed Contactors for High Pressure Extraction

Abstract

The performance of various contactors in high pressure extraction service was studied. The mass transfer efficiency of a spray column and columns filled with sieve trays, 1.27 cm ceramic Raschig rings, and no. 15 metal Intalox saddles were obtained from a “windowed” high pressure extraction column with an internal diameter of 9.88 cm and a column height of 168 cm. The extraction column has an internal diameter of 9.88 cm and a contacting height of 168 cm. Glass windows in the extractor allowed visual observation and photography. Supercritical and liquid carbon dioxide were used to extract isopropanol from water at pressures of 81 to 150 atmospheres and 297 to 318 [ddot]K. The sieve tray extractor yielded the highest mass transfer efficiency followed closely by Raschig rings and metal Intalox saddles. The spray column was by far the least efficient. The mass transfer efficiency was observed to be independent of the operating conditions studied in this work. Sauter mean drop diameters and dispersed phase (free) hold-up were also obtained in this work. These data will provide a reliable high pressure mass transfer and hydraulic database for future correlation and design efforts.     

导向格栅规整填料萃取塔的操作性能

对一种新开发的导向格栅规整填料萃取塔的水力学特性和传质性能进行了系统的实验研究。结果表明,新型导向格栅填料萃取塔的通量比传统萃取塔有了大幅度的提高,当流速比L_R(分散相:连续相)为1:5时,液泛通量达到150 m³·m^-2·h^-1。该填料萃取塔同时具有较好的传质性能,在石油炼制溶剂脱沥青、煤化工废水萃取脱酚等工业过程有良好的应用前景。     

撞击流-旋转填料床萃取器传质性能研究

以磷酸三丁酯(煤油)-苯酚-水为试验体系，研究了IS—RPB萃取器的传质性能。在研究主要操作参数对萃取级效率影响的基础上，确定了最适宜的操作条件，得到了97％以上萃取级效率。试验结果表明，撞击流-旋转填料床萃取器是一种新型快速高效的萃取设备。     

Trays for gas-liquid contacting

A type of tray for gas-liquid contacting is described, in which the free area for gas flow through the tray is variable with and controlled by the gas flowrate. The property through which control of the free area is effected is the surface tension of the liquid phase. The advantages are the same as those of ballast and valve trays; namely, reduced pressure drop at high gas rates resulting in increased column capacity, and reduced free space at lower gas rates resulting in high mass transfer efficiency at low and medium vapor loadings as well. Tooling and production costs for the trays of the present investigation, however, are considerably lower than for ballast or valve trays or any other types which require machining operations in their fabrication, and are as low or lower than for sieve trays. Initial experimental comparisons with conventional trays demonstrated that the trays of the present investigation, although designed primarily for operation at high vapor loadings, were indeed capable of yielding high mass transfer efficiencies in the low-to-medium range of vapor loading     

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.     

Monte carlo simulation of mass transfer in liquid-liquid dispersions

A simulation technique is developed to predict the performance of a two phase liquid-liquid continuous flow stirred tank reactor as an extractor. The dynamics of the dispersed phase droplet interactions and the microscopic interphase mass transfer in the turbulent flow field are digitally simulated using the interval of quiescence method. The use of realistic breakage and coalescence functions together with the natural evolution of the interactive drop population has made it possible to predict the dispersed phase drop size distribution and mass transfer efficiency in a rational manner from the known physicochemical properties of the dispersion and the operating conditions of the extractor.     

Number of Trays in Gas–Liquid Columns in Case of Intensive Entrainment: Broadening of the Kremser Equation

The paper deals with the tray efficiency estimation in the presence of entrainment, using one-parametric diffusion model for the column as a whole. The case of mass transfer in the trayed column accompanied by intensive entrainment of liquid is analysed, when both equilibrium and ‘dry working regime’ operating lines are straight. Using proposed algorithm it is possible to determine the number of actual trays in the column based on the inlet and outlet concentrations in one phase, inlet concentration in the other phase and the characteristics of mass transfer at trays. The obtained equations present the broadening of well-known Kremser equations.     

影响精馏塔板效率因素探讨

塔板效率是实现产品分离的关键因素，本文详细介绍了泄漏、雾沫夹带、塔板的液向泛混等因素对塔板效率的影响，并对导出的计算板效率的经验关联式进行了分析，提出了提高塔板效率的几点建议。