Abstract: In the evaporation crystallization unit of wet flue gas desulfurization process, the medium inside the pipeline is mainly a liquid-solid two-phase fluid. Improper equipment layout and pipeline design can easily cause solid particle precipitation and deposition, resulting in certain erosion and wear on pipelines, elbows, etc. Starting from engineering practice, this article systematically reviews the layout and pipeline design of the main equipment of the evaporation crystallization system in a certain device. A fluid flow model (CFD) is used to simulate and analyze the erosion of elbows with different curvature radii that affect the long-term operation of the device. The distribution of fluid velocity field, pressure distribution, particle motion trajectory, and erosion rate inside the pipeline are studied. It is proved that using elbows with a curvature radius of 3D, 6D, and others can effectively reduce the erosion and wear of solid particles in the fluid on the pipeline, ensuring the long-term operation of the device.

Key words: font-family:-apple-system, blinkmacsystemfont, ", font-size:14px, background-color:#FFFFFF, ">three-effect evaporation crystallization, pipeline design, elbow erosion prevention, liquid-solid two-phase flow, velocity field, pressure field, particle motion path, erosion rate

摘要： 在湿法烟气脱硫工艺蒸发结晶单元，管道内介质流动以液固两相流体为主，设备布置及管道设计不合理易造成固体颗粒析出沉积，对管道、弯头等存在一定的冲蚀磨损。从工程实际出发，系统梳理了某装置蒸发结晶系统主设备的平立面布置、管道设计，并采用流体流动模型（CFD），对影响装置长周期运行的不同曲率半径的弯头冲蚀情况进行模拟分析验证，研究管道内的流体速度场分布、压强分布、粒子运动轨迹和冲蚀速率分布图，证明使用3D、6D等曲率半径弯头，能有效减少流体中固体粒子对管道的冲蚀磨损，保证装置的长周期运行。

关键词: font-family:-apple-system, blinkmacsystemfont, ", font-size:14px, background-color:#FFFFFF, ">三效蒸发结晶, 管道设计, 弯头防冲蚀, 液固两相流, 速度场, 压力场, 粒子运动轨迹, 冲蚀速率