水力旋流器的底流口直径对其分离性能的影响

底流口直径对旋流器的性能有着非常显著的影响。本研究采用体积法测量并计算了颗粒浓度和分离效率,在流化催化裂化(FCC)催化剂-水液固体系内考察了底流口直径对水力旋流器分离性能的影响。发现在入口浓度不同时,底流口直径对旋流器性能的影响规律不同。在低浓度体系(C入≤10%)内,随着底流口直径的增加底流液浓度急剧减小,但溢流液浓度基本不变。在高浓度体系(C入≥15%)内,随底流口直径的增加底流液浓度变化不大,但溢流液浓度显著降低。在本实验范围内,随着底流口直径的增加,分流比显著增加,分离效率明显增加,压降略有降低。     

离散相入射位置对旋流器分离性能的影响研究

采用欧拉-拉格朗日方法(DPM)对液-液分离水力旋流器内部油滴运移轨迹及其分布规律进行了数值模拟分析,对油滴由旋流器入口截面不同位置进入旋流器的运移情况进行研究。得出在离散相油滴入口不同位置进入旋流器时其运移轨迹有所不同,且呈现出一定的规律性,结果表明:(1)油滴由入口处轴向上距上盖板2~2.5 mm区域进入时,易形成影响旋流器分离性能的短路流、盖下流、循环流等;(2)油滴由入口截面右下方区域径向0~0.5 mm轴向上0~7.6 mm区域内进入旋流器内时,其运移轨迹均由底流口逃逸。由此外的其它区域进入旋流器内的油滴粒子,较易被溢流口捕获;(3)可通过控制离散相油滴在旋流器入口处的入射区域,减少底流逃逸率从而提高旋流分离性能。     

数值模拟在旋流器操作性能研究中的应用

针对结构已确定的典型固-液分离型旋流器,从实验和数值模拟两方面入手研究其操作性能,重点考察了压力降与流量以及底流分率与流量之间的关系。结果表明,实际实验结果和数值计算结果相一致。为利用计算机仿真研究旋流器内流场及操作特性提供了一种新的验证方法,解决了数值模拟在流场分析中的普遍应用与验证困难之间的矛盾。     

含气条件对井下油水分离旋流器性能影响的数值模拟

为探究气体对井下油水旋流器性能的影响规律,针对新型螺旋流道倒锥式旋流器,采用Fluent软件对气液比分别为0.01、0.03、0.05、0.08、0.10时旋流器的油相分布进行模拟分析。通过对比分析发现:不含气时旋流器的分离效率为89.31%;在结构参数和分流比不变的条件下,旋流器分离效率随气液比的增加呈降低趋势,气液比为0.10时,分离效率为36.90%;气液比越大,溢流口的油相体积分数越小,底流口的油相体积分数越大;溢流口和底流口的压力损失随气液比的增大而递减。     

新型旋流器在细粒级废水浓缩中的研究应用

含微细颗粒废水浓缩是电厂湿法脱硫工艺中重要一环,目前,该环节中使用的分级浓缩旋流器为Φ40单锥体结构,直径小、锥角小、底流口堵塞严重。针对这一问题,设计了一种Φ75双锥结构旋流器,由锥角不同的两个锥段组成,既解决了小直径旋流器底流口易堵塞的问题,又提高了旋流器分离效率。现场运行结果表明,Φ75双锥旋流器分离粒度d50为16.8μm,底流产率可以达到37.6%,与常规单锥体Φ40旋流器分离性能基本一致;研究同时表明入料压力对底流浓度的提高影响显著,对底流产率的影响较小;底流口直径对底流浓度和底流产率影响较大。采用设计的Φ75双锥结构替代Φ40单锥体旋流器后,现场运行堵塞几率大幅度降低,有效解决了生产中存在的难题。     

充气水力旋流器用于油水分离的试验研究

研究了充气量、进料量、分流比以及底流出口压力等主要操作参数对充气水力旋流器分离效率影响的规律 ,得出了较好的工况点 ;与相同结构参数的未充气旋流器的分离性能进行了对比 ,结果表明 ,充气旋流器能明显改善油水分离条件 ,具有较宽的操作弹性和较高的分离效率 ;同时用库尔特粒径分析仪分别测定了它们进口和底流口油滴的粒径分布 ,发现在旋流器中充入空气 ,强化了气浮 ,能够进一步分离更细粒径的油滴。     

液-液旋流器分流比特性系数研究

通过实验证明 :分流比特性系数的大小决定了溢流口、底流口含油浓度高低 ,影响了旋流器油水分离性能。对预分离旋流器 ,分流比特性系数的合理选择 ,尤其显得重要。     

磁力旋流器分离性能的试验研究

为了解决陶瓷、化工生产领域内浆液脱铁的工程问题,开发了一种可以自动排料的磁力旋流器,并通过试验研究和理论分析的方法,对比研究了入口流量、底流分率对磁力旋流器分离效率的影响。结果表明:磁力旋流器可以通过磁系吸附浆液中的铁化合物颗粒。对比试验结果,可以得出结论:磁力旋流器内铁化合物颗粒的径向沉降速度随进口流量的增大而减小。磁力旋流器的分离效率随进口流量的增大而减小,其分离效率与进口流量的关系与理论推论相符。对于单固相铁粉浆液,磁力旋流器的分离效率随底流分率的增大而减小;对于多固相铁粉浆液,磁力旋流器的分离效率随底流分率的增大先增大后减小,当底流分率为0.55时,分离效率最高。     

溢流循环水力旋流器流场特性的数值分析

针对旋流器在运行过程中所产生的短路流、循环流以及分离效率低等现象,提出了一种溢流循环水力旋流器。依据计算流体力学,应用FLUENT软件对其进行了数值模拟,并与现有的双锥水力旋流器进行对比分析,研究了介质条件及操作参数对该旋流器的流场以及分离性能的影响。研究结果表明:溢流循环结构能够改善水力旋流器内部的短路流以及循环流现象,保持原有流场的稳定,还能有效地提高内侧溢流口轻质相体积分数,降低底流口轻质相体积分数,最终实现油水两相高效分离。     

脱水型与脱油型旋流器两级串联的现场实验研究

研究采用了两级旋流器串联的旋流工艺,通过第一级脱水旋流器和第二级脱油旋流器的联合作用,对含油体积分数为40%左右的采出液进行预处理。基于对两级旋流器分离效率、压力场和油相分布的数值模拟,建立了现场试验工艺流程,对模拟结论进行验证和分析。数值模拟结果在现场实验中可信度高。当采用最佳操作参数时该工艺可获得较高的综合分离效率。溢流汇合后的低含水油完全可以达到电脱水处理工艺的进入指标,而第二级旋流器底流排出液的含油率也达到了进入污水处理站的指标要求。     

Performance of a New Geometry of Deoiling Hydrocyclones: Experiments and Numerical Simulations

A new geometry of liquid‐liquid hydrocyclones is proposed seeking to perform the separation of oil emulsified in water. The hydrocyclone performance was investigated by means of a factorial experimental design (2³) leading to a total of ten experiments. The results enabled the determination of empirical mathematical models that describe capacity, total separation efficiency, and flow ratio as a function of oil concentration in the feed inlet, operating pressure drop, and presence or absence of a vortex finder in the geometry. Numerical simulations were also carried out to further understand the flow field characteristics in the studied hydrocyclone.     

Study of Air‐Liquid Flow Patterns in Hydrocyclone Enhanced by Air Bubbles

In order to improve the oil‐water separation efficiency of a hydrocyclone, a new process utilizing air bubbles has been developed to enhance separation performance. Using the two‐component phase Doppler particle analyzer (PDPA) technique, the velocities of two phases, air and liquid, and air bubble diameter were measured in a hydrocyclone. The air‐liquid mixing pump can produce 15 to 60 μm‐diameter air bubbles in water. There is an optimum air‐liquid ratio for oil‐water separation of a hydrocyclone enhanced by air bubbles. An air core occurs in the hydrocyclone when the air‐liquid ratio is more than 1 %. The velocities of air bubbles have a similar flow pattern to the water phase. The axial and tangential velocity differences of the air bubbles at different air‐liquid ratio are greater near the wall and near the core of the hydrocyclone. The measured results show that the size distribution of the air bubbles produced by the air‐liquid mixing pump is beneficial to the process where air bubbles capture oil droplets in the hydrocyclone. These studies are helpful to understand the separation mechanism of a hydrocyclone enhanced by air bubbles.     

油水分离剂在化学驱采出液和含油污水处理中的应用

针对大庆油田聚北-1联合站处理的化学驱采出液和含油污水因含有表面活性剂(52 8mg/L)、碱(294 5mg/L)和聚合物(347 5mg/L)而油水分离困难,造成该站处理后污水含油量严重超标的问题。从非离子型药剂的思路出发研制了适用于含表面活性剂、碱和聚合物的反相原油乳状液的油水分离剂。在聚北-1联合站原有的两级沉降和一级石英砂过滤含油污水处理工艺不变的条件下,在采出液中投加60mg/L本文研制的油水分离剂(药剂费用为0 51元/m3)后,该站处理后污水的平均含油量由投加油水分离剂前的99 0mg/L降低到9 9mg/L。     

液相磺化法制备三次采油用石油磺酸盐

研究了克拉玛依炼厂减压四线糠抽馏分油与液相三氧化硫在1,2-二氯乙烷溶剂存在下的磺化反应,磺化产物经中和、分水、浓缩等处理,得到石油磺酸盐产品。采用阳离子两相滴定-比较分析法测定反应产物中的活性物含量,讨论了酸油比、反应温度、溶剂与油的比例、加酸速度及老化时间对活性物含量的影响。结果表明,酸油比、反应温度和加酸速度对活性物含量影响较大,溶剂和油的比例次之,而老化时间对活性物含量的影响较小,优化条件下活性物含量高达67.27%。     

文昌13-1/2油田新型油田污水处理方法实践

海上油气田传统的生产水处理方法采用水力漩流器,能耗高,生产水泵维修成本高.近年来出现了采用旋转离心分离和气浮分离为工作原理的新型油田生产水处理设备,大幅度降低了生产水的含油量.装置还具有能耗低、操作简单、成本低、占地面积小等一系列特点.     

Oil-water separation using hydrocyclones enhanced by air bubbles

In order to improve the separation efficiency of dispersed oil from water by hydrocyclones, a new process of utilizing air bubbles has been developed to enhance the separation efficiency. The air bubbles attach themselves to the oil droplets and cause a decrease in the overall density of the phase, the difficulty of agglomerating can thus be circumvented. The air-liquid ratio of 1% was found to provide the best separation. When the inlet Reynolds number ranges from 14,000 to 16,000, the oil removal efficiency increases from 72% (air-liquid ratio 0%) to 85% (air-liquid ratio 1%). The process has been found to be very efficient in the separation of suspended oil from water.     

Sub-micron particle dewatering using hydrocyclones

Hydrocyclones are used for dewatering of solid–liquid suspensions in many industries. Generally, however, large diameter cyclones are used and their application is restricted to large (>25 μm) particles. Small diameter (10 mm) hydrocyclones have the potential to be applied to fine particle (<10 μm) suspensions and, in particular, to collect the sub-micron fraction. This is due to the very small cutsizes that are achieved in these cyclones. In order to apply these small hydrocyclones industrially, knowledge of the range of their classification performance is required. It is found that these cyclones exhibit a fish-hook partition curve, and a high bypass fraction. The very small cutsize (<5 μm) and the relatively large bypass makes the effective collection of sub-micron particles possible. While in most hydrocyclone applications it is found that the bypass fraction equals the water recovery to the underflow, in 10 mm hydrocyclones the bypass fraction is considerably larger than the water recovery. This results in a high particle recovery to the underflow, as well as low water recovery, resulting in a high concentration ratio. Results will be presented to show the separation performance of different hydrocyclone outlet configurations and pressure drops. A general model will be presented that describes the fish-hook and that gives an explanation for its origin. It will be shown that 10 mm hydrocyclones yield a new operating regime for their application to sub-micron solid–liquid separation, as a result of high solids recoveries and low water recoveries.     

LD5-2原油油水分离研究

以LD5-2海上稠油为研究对象,研究了该油田在开采过程中存在的油水分离问题。通过分析LD5-2采出液及原油性质,探讨了稠油油水分离动力,并考察了温度、电压等参数对油水分离工艺的影响。研究结果表明:LD5-2原油具有特稠油的性质,粘度高、常温难以流动,同时又具有较小的油水密度差,造成油水分离困难;通过优化,在温度130℃、破乳剂A1用量400μg·g~(-1)、电压1 200 V、停留时间45 min条件下原油脱后含水可满足5%的外输要求;油水分离温度、电压及破乳剂对LD5-2脱水效果影响较大;40%含水的采出液粘度存在突增现象,应予以重视。     

Study of the Performance of a Novel Hydrocyclone Built in the Configurations of the Classical Families

The performance of classical families of hydrocyclones (Bradley, Rietema, and Demco) has been compared with a novel equipment, the filtering of hydrocyclones. In the filtering of hydrocyclones, the conical section is replaced by a conical filtering wall producing another liquid stream leaving the equipment besides underflow and overflow streams. In the present paper, the influence of the filtering conical wall in the classical geometries was analyzed by experimental and CFD studies. The results showed that the replacement of the conical section of hydrocyclones built with classical geometries by a filtering cone have significantly changed their performance. In general, the separation performance and the capacity can be enhanced with the filtering hydrocyclones.     

Mini-hydrocyclones application in the reduction of the total oil-grease (TOG) in a prepared sample of produced water

The process of de-oiling produced water from offshore oil fields was evaluated using hydrocyclones. An experimental design was employed and the results were used to create an empirical model that describes the reduced separation efficiency as a function of different concentrations of infeed and the pressure drop. A study was made of the procedure for preparing the oil-water emulsions used here in order to reproduce the TOG of the produced water generated in oil field. A procedure to verify the operation of these devices demonstrated that six hydrocyclones operating in tandem can attain the legally acceptable concentration of oil in the treated effluent.