固液旋流分离器壁面磨损的研究

发布时间：2018-04-21 15:41

本文选题：旋流分离器 + 液固两相流　；参考：《西南石油大学》2017年硕士论文

【摘要】：固液旋流分离器由于具有结构简单、操作方便、分离效率高等优点,在原油除砂、化工分离和矿浆浓缩等方面得到了广泛应用。但是,在实际工业应用过程中,固液旋流分离器也存在一些问题,主要表现在动力消耗大、运行周期短、壁面磨损严重等方面。其中,壁面磨损问题是制约着固液旋流分离器的发展的首要问题。壁面磨损会加快分离器的失效,使用寿命和分离效率严重降低。从目前国内外研究现状来看,人们对固液旋流分离器的认识还不够深入,多数结论认识都来自现场经验,对于影响壁面磨损的因素更是缺乏系统的分析。本文针对固液旋流分离器壁面磨损问题,基于计算流体力学(CFD)方法,采用数值模拟与理论分析相结合的方式,深入的研究了固液旋流分离器壁面的磨损情况。首先介绍了利用CFD商业软件Fluent求解固液旋流分离器壁面磨损的计算方法。然后基于固液两相流的基本理论,对固液旋流分离器内部流场进行了分析。先求出以常温下清水为介质的单相稳定流场,加入离散相颗粒。最后深入分析了液固两相流中粒子的运动特征,得到颗粒与壁面的碰撞角度、碰撞速度以及碰撞位置等信息,通过带入所选取的磨损量计算公式,即可得到分离器壁面情况。通过模拟试验得到的压力降结果与文献实验结果的对比,验证了本次模拟的准确性。在上述基础上,计算模拟了固液旋流分离器壁面的磨损情况。结果表明:固液旋流分离器壁面磨损为局部磨损,主要磨损部位有入口环形空间部分区域、圆筒体的磨损带区域以及圆锥体下端区域。环形空间壁面在圆周方向位置,壁面磨损随着方位角的增大呈先增大后减小的分布趋势;圆筒体壁面磨损率成波状分布,有较为明显的波峰和波谷;在圆锥体部分沿着轴向向下壁面磨损率越来越大,在锥体末端附近达到最大值,随后又明显降低。研究了不同结构参数(锥角大小、溢流管直径、入口面积)、入口形式、以及工况参数(入口速度、粒子浓度、粒径大小)对固液旋流分离器壁面磨损的影响规律。研究结果表明:这些参数都是影响固液旋流分离器壁面磨损的重要因素,对固液旋流分离器壁面磨损部位分布以及壁面磨损率都有着不同程度的影响。通过本文的分析研究工作,能够为固液旋流分离器的结构改进、尺寸优化以及防磨措施提供指导依据。
[Abstract]:Solid-liquid cyclone separator has been widely used in crude oil sand removal, chemical separation and slurry concentration because of its advantages of simple structure, convenient operation and high separation efficiency. However, in the process of practical industrial application, there are some problems in solid-liquid cyclone separator, such as large power consumption, short running period, serious wall wear and so on. Among them, wall wear is the most important problem that restricts the development of solid-liquid cyclone separator. Wall wear will speed up the separator failure, service life and separation efficiency seriously reduced. From the current research situation at home and abroad, people's understanding of solid-liquid cyclone separator is not deep enough, most of the conclusions are from field experience, and the factors affecting wall wear are lack of systematic analysis. In this paper, based on the method of computational fluid dynamics (CFD) and the combination of numerical simulation and theoretical analysis, the wall wear of solid / liquid cyclone separator is studied in depth, aiming at the problem of wall wear of solid / liquid cyclone separator. First, the calculation method of wall wear of solid-liquid cyclone separator by CFD commercial software Fluent is introduced. Then, based on the basic theory of solid-liquid two-phase flow, the internal flow field of solid-liquid cyclone separator is analyzed. The single phase steady flow field with clear water as the medium at room temperature is obtained, and discrete phase particles are added. Finally, the motion characteristics of particles in liquid-solid two-phase flow are analyzed in depth. The impact angle, collision velocity and collision position of particles and wall are obtained, and the wall condition of separator can be obtained by introducing the selected formula to calculate the wear quantity. The accuracy of the simulation is verified by comparing the pressure drop results obtained from the simulation experiments with the experimental results in literature. On the basis of the above, the wall wear of solid-liquid cyclone separator is simulated. The results show that the wall wear of the liquid-solid cyclone separator is local, and the main wear parts are the entrance ring space, the wear zone of the cylinder and the lower end of the cone. In the circumferential direction of circular space, the wall wear increases first and then decreases with the increase of azimuth angle, and the wall wear rate of the cylinder becomes wave-like, with obvious wave peaks and troughs. The wear rate of the pyramidal part along the axial downward wall is increasing, reaching the maximum near the end of the cone, and then decreasing obviously. The effects of different structural parameters (cone angle diameter of overflow pipe inlet area) inlet form and operating conditions (inlet velocity particle concentration particle size) on wall wear of solid-liquid cyclone separator were studied. The results show that these parameters are important factors affecting wall wear of solid-liquid cyclone separator, and have different effects on the distribution of wall wear and wall wear rate of solid-liquid cyclone separator. Through the analysis and research work in this paper, it can provide the guidance basis for the structure improvement, the dimension optimization and the anti-wear measures of the solid-liquid cyclone separator.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ051.8

【参考文献】