水力旋流器结构与分离性能研究（三）：锥段结构

研究了水力旋流器锥段结构开关肥及锥段体积对其分离性能的影响，结果表明：采用螺旋型锥段结构时水力旋流器处理能力最高；采用抛物线型锥段结构时水力旋流器的分离修正总效率最高，分离精度最高，分流比最小；采用普通型光滑直锥时旋流器分离粒度最小，随着光滑内壁型锥段体积的增大，旋流器分离修正总效率呈线性提高，而旋流器分流比则呈线性下降。     

水力旋流器结构与分离性能研究（六）：柱段结构（长度）

研究了水力旋流器主段长度对其分离性能的影响，结果表明，随着柱段长度的增大，水力旋流器处理能力呈单调上升趋势，其分离修正总效率呈上升趋势，其溢流浓度则呈单调减小趋势，在水力旋流器用于固液分离场合时，其柱段长度宜较长为佳。     

水力旋流器分离空间匹配优化研究

首次系统地研究了水力旋流器分离空间匹配系数对其分离性能和能量耗损等方面的影响，结果表明，随着柱锥空间比值的增大，分离修正总效率上升，能耗系数降低，分离粒度和分离精度则呈二次曲线形变化。最后给出了适应不同场合要求的水力旋流器的最佳分离空间匹配系数和圆筒段长度推荐值。     

中心棒对石膏旋流器工作性能的影响

针对火电厂石膏旋流器运行中存在空气柱及底流夹细等问题,设计倒锥形中心棒取消空气柱,改善石膏旋流器的工作性能。采用实验方法分析不同入口压强下石膏旋流器性能的变化情况,得到无中心棒、圆柱形中心棒、倒锥形中心棒对生产能力、底流浓度、底流含固量以及底流浆液中石膏颗粒分布的影响。结果表明：与无中心棒相比,采用倒锥形中心棒能够使生产能力提高18%,底流含固量增大22%,分级性能对入口压强具有良好的适应性,并能够有效缓解底流夹细现象。     

锥齿型水力旋流器的分离特性研究

对锥齿型水力旋流器的性能进行了试验研究，结果表明这种新型水力旋流器的分离精度、分流比、分离粒度和总分离效率均高于普通水力旋流器的相应指标。还研究了中心锥的几何参数和位置对分离特性的影响。     

水力喷射空气旋流器分离空间结构对气液传质性能的影响

水力喷射空气旋流器(WSA)是一种利用液体射流在气体旋流场中雾化强化气液传质的新型传质设备, 可广泛用于废水、废气处理等环境工程过程中。为了优化水力喷射空气旋流器的分离空间结构, 本文通过废水氨氮吹脱实验对柱锥结合形WSA和柱形WSA分别进行了气液传质性能研究。研究结果表明, 分离空间结构对水力喷射空气旋流器的气液传质性能存在影响。在相同工作条件下, 与柱形WSA相比, 柱锥结合形WSA具有更好的气液传质性能和略高的气相压降, 后者吹脱氨的体积传质系数提高了约8%, 主要原因在于柱锥结合形WSA内部具有更好的射旋流耦合雾化作用和离心超重力强化传质的综合效果, 使得两相比传质面积增大, 传质效率增高。研究结果可为设计传质性能良好的WSA提供设计依据。     

分离空间结构对旋流器流场和传质面积的影响

为了揭示分离空间结构对水力喷射空气旋流器(WSA)的气液传质性能影响作用机理,采用雷诺应力模型(RSM)和流体体积多相流(VOF)模型对圆柱型和柱锥结合型水力喷射空气旋流器内部耦合场进行了数值模拟,并以CO_2-NaOH化学吸收体系测定了这2种分离空间结构WSA的有效比相界面积。结果表明:分离空间结构对WSA内的射-旋流耦合场中轴向、切向和径向速度分布都有较大影响。柱锥结合型WSA的耦合场具有较高的切向速度、较低的轴向速度和较稳定的径向速度;而圆柱型WSA的耦合场具有较大的轴向速度、较小的切向速度和稳定性较小的径向速度场。与圆柱型WSA相比,柱锥结合型WSA的流体湍动能和有效比相界面积高于前者,这是后者传质效率高的主要原因。     

含聚合物工况下旋流器分离特性的CFD-PBM数值模拟

以螺旋导流内锥式旋流器为研究对象,基于幂律流体模型对含聚合物工况下旋流器内油滴的聚结现象及其对分离性能的影响进行了CFD-PBM数值模拟。结果表明:增加聚合物的浓度,使油滴在锥段内的轴向运动距离延长,边壁附近油滴粒径逐渐增大,增加了油滴从溢流口流出的难度,使分离效率大幅降低;在含聚合物的工况下,增大入口流量使油滴在旋流器轴心区域聚结现象非常明显,分离效率从37.63%提高至80.86%;增加入口含油浓度可以大幅提高旋流器内油滴碰撞聚结的几率,油滴粒径大幅增大,但分离效率会先增后降,入口含油浓度4%时分离效率最高(73.53%)。     

水力旋流器结构与分离性能研究（二）：溢流管结构

研究了水力旋流器溢流管结构形状对其分离性能的影响，结果表明：溢流管采用３０°渐扩管加锥结构时，水力旋流器处理能力最高；溢流管加虹吸装置时，水力旋流器分离修正总效率最高、分流比最小；采用普通型薄壁直圆管结构时，水力旋流器修正分离粒度ｄ５０Ｃ最小、分离精度α值最高。     

高海拔地区水力旋流器旋液分离过程CFD模拟与结构优化

针对氯化钾冷结晶器溢流液分离问题，提出使用水力旋流器进行固液分离。采用CFD数值模拟方法对水力旋流器的分离过程进行计算，研究在高海拔地区下水力旋流器筒径、溢流口直径、入口流速、锥角等因素对其流动特性和分离性能的影响。结果表明：筒径Dc=200 mm时分离效果最好；溢流口直径d0的增大会使分离效率与压降减小；增大入口流速会使分离效率先上升再下降，且压降随入口流速增大而增大；锥角α减小，水力旋流器分离效率增加并且压降减小，海拔高度的改变基本不改变水力旋流器的分离效率与压降。经分析可知：当Dc=200 mm、d0=56 mm、α=10°、入口流速为9 m/s时，粒径在20μm以上的颗粒分离效率可以达到80%以上，此时压降为0.26 MPa，整体性能最好。     

Experimental study on the separation performance of air-injected de-oil hydrocyclones

The developing status and separating principle of de-oil hydrocyclones are first simply introduced. The ways to enhance the hydrocyclone's separation efficiency are described based on theoretical analysis. One of the ways is to inject air into the hydrocyclones so as to combine them with oil to form oil–gas compound bodies, and then increase the de-oil efficiency. By means of injecting air into the hydrocyclone, a new type of hydrocyclone, i.e. air-injected de-oil hydrocyclone (AIDOH), was developed. The basic separation principle of the AIDOH, prototype structure, the experimental technical process and facilities are introduced. Laboratory experiments were carried out. The effects of different geometric parameters, including the vortex finder diameter, and the length, the micro-pore diameter, and different operating conditions, such as flowrate, split ratio, gas–liquid ratio, and especially the air-injecting position, were studied. It was also found that the best injecting part is at the fine cone segment. Further experimental studies were continued to confirm the detailed part in the fine cone segment, which included one-third segment and two-thirds segment. Results show that the best air-injecting part is the first one-third of the fine cone segment. Research indicates that the AIDOH has satisfied the separation effect.     

三次曲线的液-液水力旋流器管形设计

以标准的Thew式旋流器结构为设计依据,把大锥段和小锥段部分用两段三次曲线和一段圆弧作为母线的腔体所取代,形成了内流道光滑的液液旋流器分离管。该管型较好地解决了流场紊乱的问题,更利于旋流分离效率的提高。     

除油水力旋流器溢流口结构试验研究

通过对旋流器溢流口结构的深入研究。设计出3种新型溢流口结构──涡流屏蔽罩式、涡流屏蔽罩和涡流探测管组合式以及实心涡流屏蔽管式溢流口。利用MARVERN激光粒度仪,在室内模拟试验装置上进行了分离性能测试,并从粒级效率和压力降两方面综合评价了3种溢流口结构的分离性能。测试和分析结果表明,溢流口直径越小,分离效率越高,压降也略有增大;涡流屏蔽罩式、涡流屏蔽罩和涡流探测管组合式溢流口可以降低压降7％以上,而分离效率基本不变;实心涡流屏蔽管式溢流口和带下倾角的入口流道组合可以大大降低旋流器的压降。     

Improvement of performance efficiency of a hydrocyclone with design modification by suppressing air core

Hydrocyclones have been used for beneficiation of coal and mineral in coal washeries and mineral process industries. To enhance the efficiency of hydrocyclone, it is very essential to quantify the presence or absence of air core within the hydrocyclone. In the present study, for the first time, a new hydrocyclone design has been conceptualized and tested for its efficiency in separation of particles based on gravity. Experimental investigations have been carried out using design of experiments and the results have been analyzed statistically. The results have shown that suppressing the air core improves the separation efficiency of the hydrocyclone. Efforts have been made to explain the concept through fundamentals of fluid flow in hydrocyclone. The air core has a significant effect on particle separation as the relative density of the particles approach to the fluid density. The results will be used in the development of a new design of dense medium hydrocyclone at industrial scale that will improve the separation efficiency of the hydrocyclones by separating the near gravity particles more efficiently.     

Studies on the performance of a hydrocyclone and modeling for flow characterization in presence and absence of air core

Hydrocyclones are getting more and more interest from various industries. They are widely used to separate particulates from liquid at high throughput because of their advantages like simple structure, low cost, large capacity and small volume, require little way of maintenance and support structure. Modeling of complex and multiphase flow behavior inside the hydrocyclone is done usually with the help of computational fluid dynamic study. Current study involves experimental investigation of separation performance characteristics of the hydrocyclone using new design parameters. For experimental purpose, a new hydrocyclone was designed with insertion of solid rod, at central portion of conical section of hydrocyclone, inside the hydrocyclone . By which air core could be eliminated effectively and hydrocyclone performance is improved. This effect may be observed due to reduction of radial and axial components of velocity and turbulence in the area near the entrance of the vortex finder. Therefore, the flow field characteristics inside the hydrocyclone with no air core become more suitable for separation. Also the effect of flow rate, vortex finder depths, air core and particle interaction were studied experimentally. A new arrangement was suggested to eliminate the air core formed inside the hydrocyclone. In this case, effect of diameter and height of solid rod inserted inside the hydrocyclone with changing total inlet flow rate was studied experimentally. Three-dimensional geometry and meshing of hydrocyclone is created in Gambit, preprocessor of commercial software—Fluent, for hydrodynamic study.     

Enhancement of hydrocyclone performance by controlling the inside turbulence structure

A new hydrocyclone was designed with a winged core fixed below the vortex finder in this study. With the winged core, the turbulence structure characteristics inside the hydrocyclone, including time-averaged pressure, pressure fluctuation, relative pressure fluctuation characteristics, and distribution characteristics of the probability density of the turbulence pressure, were all positively controlled. By controlling the turbulence structure, the performance of the new hydrocyclone was improved effectively. Compared with the common hydrocyclone, the new hydrocyclone was featured with lower energy loss coefficient, higher reduced separation efficiency, higher separation sharpness and larger capacity.     

旋流器内空气核的形成机理和形状的实测研究

首次采用先进的高速摄象机对旋流器内空气核的出现、发展直至形成的整个过程以及形成后的形状进行了全面系统的实测研究。研究发现空气核的形成经历了孕育、发展及形成三个不同的阶段;在旋流器内不同的高度,空气核的形状有所不同,在底流口上端发生最大程度的偏摆,而在溢流管内出现类似“葫芦”形状;旋流器的进口流量和锥角对空气核的形成过程及形状尺寸有着重要的影响。空气核的形成运动过程为一随机过程,这是造成分离过程具有随机特性的主要因素之一。     

Effect of a Cylindrical Permeable Wall on the Performance of Hydrocyclones

Hydrocyclones are designed for solid‐liquid separation widely used in industry due to their advantages including high separation efficiency. Depending on the purpose desired by the user, it is possible to enhance the performance of the hydrocyclone through the combined use of other unit operations with the hydrocycloning such as filtration. The incorporation effect of a porous cylinder on a hydrocyclone with optimized geometry was studied experimentally. According to the main results, the filtering cylindrical hydrocyclone showed significant average reductions in energy consumption compared to conventional hydrocyclones of the same geometry. Minor differences in terms of total efficiency of the filtering equipment were observed compared to the conventional one.     

The velocity distribution within a hydrocyclone operating without an air core

The three dimensional flow patterns in a 3-in. diameter hydrocyclone operating without an air cone were studied using tracer particles and cine photography. Analysis of films at 55 locations inside the hydrocyclone yielded data for 18 velocity profiles at six vertical positions. These data were checked for consistency and compared with the results of earlier work in hydrocyclones operating with air cores. The tangential velocity profiles were found to be similar to those produced with an air core although, n. in V_AIⁿ = const, is about 0.2 to 0.4 instead of 0.7 to 0.8 for air core operation. In this work the radial velocity component was relatively independent of radius.     

Improvement of hydrocyclone separation performance by incorporating a conical filtering wall

In this work, the performances of conventional hydrocyclones have been compared with a new configuration, known as filtering hydrocyclone. This non-conventional solid–liquid separator consists of a hydrocyclone whose conical section is replaced by a conical filtering wall. Thus, during the operation of these devices, besides the underflow and overflow streams, there is another stream of liquid, resulting from the filtrate produced in the porous cone. The experimental and CFD results, obtained in 25 different configurations of both conventional and filtering hydrocyclones, show that the performance of hydrocyclones is significantly influenced by the replacement of the conical section of the conventional device by a conical filtering wall. The separation performance and the capacity can be enhanced with the filtering hydrocyclones, as compared with similar conventional.