结构形式对聚结器性能影响的数值分析

利用计算流体动力学(Computational Fluid Dynamics,CFD)软件Fluent,采用群体平衡模型(Population Balance Model,PBM),以常规双锥型液-液旋流分离器结构为基础,研究聚结器Ⅰ～Ⅵ(不同结构形式)对聚结性能的影响。分析了不同截面上油相体积分布、油相粒径分布及油相迹线分布等,对不同粒径聚结性能的影响,获取了不同结构形式聚结器出口粒径分布和变化规律。结果表明:油相在聚结器Ⅴ经聚结后出口粒径最大可以达到290μm,且含有粒径270、290μm的油相数量最多。同时在截面3,聚结器Ⅴ粒径最大,且整体看聚结器Ⅴ粒径大多集中在200μm,表明聚结器Ⅴ聚结效果最好。     

聚结器浓度场的数值模拟

为优化聚结器结构,应用计算流体力学（CFD）方法,选用RNG k-ε模型,以SIMPLE算法为基础,对旋流式和蛇形管式聚结器在湍流状态下的流体流动场进行数值模拟,得出该两种结构聚结器的油相浓度分布云图。数值模拟结果表明,蛇形管式聚结器对油滴的兼并和聚结效果优于旋流式聚结器。     

液态氯乙烯两种脱水技术对比

为了降低水在聚氯乙烯生产中对单体及聚合质量的影响,可采用聚结器脱除水分。阐述了聚结器的分离原理和技术特点。用实例对比了聚结器脱水新技术和传统脱水工艺固碱吸附器脱水技术两种技术的实际运行指标及成本分析。     

新型液-液分离设备——斜板沉降器

介绍了斜板沉降器的结构和操作特性，并对液滴在斜板层膜上的聚结过程以及影响液滴聚结的因素进行了分析；提出了液滴在斜板上有效聚结作为斜板沉降器的设计依据，最后对斜板沉降器的进一步研究重点提出了建议。     

高效聚结器在氯乙烯生产中的应用

介绍了氯乙烯深度脱水工艺及聚结器脱水原理,将高效聚结器应用于氯乙烯精馏工序中,实现了氯乙烯的深度脱水,满足了聚合工序的工艺要求,提高了产品的质量。     

玻璃纤维聚结器脱除油中乳化水

随着油水分离技术的进步及新材料的开发,聚结法脱除油中乳化水的技术得以实现。本文采用亲水性玻璃纤维作为聚结元件,脱除白油中的乳化水（d₉₅=10μm）。通过实验考察聚结器中进料的表观流速（5~30m/h）、油品初始含水量（500~4000μL/L）、聚结器床层厚度（100~400mm）和玻璃纤维的孔隙率（0.80~0.95）对聚结分离效率的影响,并应用响应面法对各变量之间的协同效应进行分析,确定最佳操作条件,分析该条件下的粒级分离效率。实验结果显示,当表观流速为14m/h、初始含水量为1278μL/L、床层厚度为275mm和孔隙率为0.85时,分离效率最高,为95.18%。结果与响应面预测值（95.02%）相比,相对误差仅为0.17%,表明回归模型的可靠性高和实验的重现性较好。进出口粒径的分析表明聚结器的分离效果随水滴粒径的增加而提高,有效分离粒径>5μm。本文研究结果对采用玻璃纤维为聚结元件,分离密度差较大的成品油中乳化水的聚结器选型及操作参数设计具有实际应用价值。     

液-液两相高效分离技术及应用

在对非均相液-液两相的分离的重要性进行阐述基础之上,分析了影响液-液两相分离的因素,主要包括液-液两相的物性、聚结材料的选择等方面。此外详细地介绍了目前普遍使用的液-液两相高效的分离措施及设备,重点介绍了目前普遍使用的三种高效的设备：单级聚结器、两级聚结分离器以及三级过滤-聚结-分离器。为实际应用中非均相液-液两相实现最经济、有效的分离提供指导作用。     

液液聚结分离器原理及石油化工中的应用

对非均相液-液两相的聚结分离机理,以纤维类介质为例,将聚结过程分为液滴捕集、液滴聚结和液滴沉降,同时也对影响聚结分离的因素进行了阐述.在此基础之上,介绍了目前在石油化工行业中应用比较广泛的高效的液-液两相分离设备:单级聚结器和二级聚结分离器,重点论述滤芯式聚结分离设备.为在石油化工领域中液-液分离提供指导和借鉴作用,为实现经济、有效的分离操作提供理论和实践支持.最后指出液-液两相聚结分离技术及设备的发展方向.     

驱油剂对油包水乳状液静电聚结特性的影响

利用新型静电聚结器室内快速评价装置结合显微拍照技术,系统研究了电场作用下驱油剂及其含量对静电聚结效果的影响规律,并利用能耗分析的方法对结果进行了分析。实验结果表明:加碱后水溶液聚结效果提高,但随着碱含量的增加,聚结效果下降;交流脉冲、直流脉冲电场作用下效果较好,高频时聚结效果较好。随表面活性剂含量增加,聚结效果先下降后提高,拐点因频率而不同,且低频时直流脉冲和交流脉冲聚结效果较好,高频时方波和交流脉冲聚结效果较好。含有聚合物的乳状液在电场作用下聚结效果先下降后上升,但超过一定含量后基本不变,方波和交流脉冲的聚结效果较好。不同情况下,低频时正弦交流能耗较低,高频时直流脉冲能耗较低,交流脉冲和方波作用下液滴聚结效果较好。     

烷基化中离子液体与烃分离的实验研究

针对离子液体烷基化反应流出物中的离子液体-烃乳化液体系,选用高效聚结纤维填料进行离子液体与烃分离实验,考察了离子液体对纤维材料的润湿性,并重点研究了采用聚结分离方法时,烷基化过程中离子液体与烃分离装置的防堵能力以及分离效果。实验结果表明,离子液体对改性纤维有较好的润湿性,该纤维填料聚结器防堵能力强且分离效果好。     

A visual study of the breakdown of emulsions in porous coalescers

A two-dimensional photoetched glass flow cell was used to observe the process by which an emulsion was broken down by a granular porous coalescer. The effects of wettability, emulsion and collector zeta potentials, and emulsion droplet size on the coalescence phenomenon were studied. The possible use of a graded medium or a coalescer with mixed wettability to enhnce the coalescence process was also examined. Based on these visual studies, a set of guidelines was developed to aid in the selection of a porous coalescer for a given separation duty.     

Study of Cutting-Oil Emulsion Separation by Coalescer Process in Terms of Medium Characteristics and Bed Packing

This work aimed to consider the effects of media shape, size, and packing on the coalescer efficiency. Different shaped polypropylene was applied as media for separating the cutting-oil emulsion. The results exhibited that polypropylene media can separate the emulsion with the highest efficiency of 43% at the optimal condition. The dissimilar shape provided the difference in the equivalent size and the packing by means of porosity, permeability, and pore uniformity. Furthermore, the approach for determining application possibility of materials as coalescer media was proposed. Wetting properties and bed permeability were suggested as key factors for media selection and coalescer process design.     

Consolidation dewatering and centrifugal sedimentation of flocculated activated sludge

This study investigated experimentally the consolidation dewatering and centrifugal-settling processes for activated sludge subjected to cationic polyelectrolyte flocculation. The results were reported for the dynamic response of sediment cake thickness (an index for cake compaction) under various doses of polyelectrolyte conditioning, compression-permeability cell configuration and mode of operation (batch and continuous) in a centrifugal-settling cell. The reduction in sediment thickness of sludge by consolidation and centrifugation was found to correspond mostly well with the optimal dose of polyelectrolyte based on the capillary suction time. The relaxation/rebound of cake thickness was observed in both consolidation dewatering and centrifugal dewatering with comparable compaction/relaxation time scale ratios. The equilibrium sediment consolidation ratio increases with the effective solid pressure characterized by P_m and P_s, for the consolidation dewatering and centrifugal sedimentation, respectively. The experimentally determined time scales of the cake consolidation dewatering/centrifugal sedimentation processes agree reasonably well with the theory by Landman and Russel (Phys. Fluids A 5 (1993) 550).     

Effect of Digested Sludge Properties on Mechanical Dewatering Efficiency: An Experimental Approach

To optimize the anaerobic digestion process of residual sludge, co-substrates addition and pre-treatments are increasingly being employed. Nevertheless, if these processes allow the optimization of biogas production, they can significantly impact the efficiency of mechanical dewatering processes for digested sludge. In this article, the impact of co-substrate addition (oily sludge) and thermal pre-treatment on the efficiency of mechanical dewatering of digested sludge was investigated. To this purpose, mechanical dewatering experiments were conducted at lab-scale by using a filtration-compression cell to determine the limit dryness of various digestates. In addition, control factors of the mechanical dewatering efficiency of digested sludge were investigated. Results highlight that 67% of the variance of the limit dryness of digestates is due to the variable “volatile solid/total solid ratio.”     

Sludge Dewatering and Aggregate Formation Effects through Taylor Vortex Assisted Flocculation

Abstract

For polymer induced flocculation processes, the effects of flow patterns in a gap of a conical stirrer on aggregate formation and subsequent sludge dewatering efficiency were analysed. Different flow regimes were identified by lab scale investigations with model substances and summarized in a Ta and Re number plane. An enhancement of sludge dewaterability for polymer induced flocculation processes was identified through post‐treatment of flocculated sludge aggregates by the specific flow pattern of stable and wavy Taylor vortices. Photo‐optical image analysis of flocculated aggregates shows a clear change of aggregate size distribution with less small particles during aggregate forming by Taylor vortices compared to classical flocculation procedure by stirrer. Results from technical scale dewatering analyses confirmed enhancement of sludge dewatering efficiency for six different dewatering machines using the identified wavy and stable Taylor vortex flow pattern regime.     

天然气聚结过滤分离技术应用

气体中夹带的微小液滴和油雾难以分离是天然气生产、输送过程中的一个突出难题,本文对国内外常用的几种气液分离技术进行了比较,着重介绍高效聚结过滤分离器的结构特点、工作原理,以及在埕岛中心三号平台天然气处理橇块中的应用。现场应用结果说明采用高效聚结过滤分离器可以将气体中的液体和固体污染物脱除到检测不出来的水平。     

聚结器在氯乙烯单体除水中的应用

介绍了河南联创化工有限公司氯乙烯单体含水的除去方法,一期采用固碱干燥,二期采用高效聚结器,运行后,树脂粉的白度有了显著提高,热稳定性等更加稳定。     

PREDICTION OF OIL SATURATION IN FIBROUS BED-COALESCER BY DYNAMIC PULSE TECHNIQUE

Average oil saturation in fibrous bed coalescer has been measured experimentally using pulse response technique. Comparable results were obtained with saturation values obtained under steady-state condition.

The experimental technique involved the injection of small amount of toluene-water dispersion in the upstream side of the coalescer and following the inlet and outlet concentration count for this dispersion. As a result of this work a coalescence rate constant, k, could be measured which gives an indication of the rate of coalescence in the bed.