FCC装置旋风分离器改进翼阀的防磨性能流场分析

Analysis of gas flow field for erosion resistance of improved cyclone wing valves in FCC unit

针对FCC装置旋风分离器翼阀由于漏风导致阀板冲蚀磨损的问题,设计了三种结构的翼阀,分别是:阀口加导流片(A型)、阀板外凸(B型)和阀板内凹(C型)。采用计算流体力学方法对三种结构翼阀周围的气相流场进行了数值模拟,并基于流场分布分析了催化剂颗粒对翼阀阀板的冲蚀磨损特点。计算结果表明:对于A型翼阀,导流片的导流作用可以防止气流夹带催化剂颗粒对阀板形成30°～40°冲击角;B型翼阀由于外凸阀板结构,在阀板表面形成一个气垫,会减弱催化剂颗粒对阀板的直接冲击;C型翼阀由于内凹阀板结构,阀板内表面易受气流的直接冲击,加剧了催化剂颗粒对阀板的冲蚀磨损。研究结果综合表明,A型和B型翼阀结构具有抑制颗粒冲蚀磨损的功能。

Three types of cyclone wing valves were designed for impingement erosion protection of cyclone separator of FCCU.Type A valve is provided with guide plate on the outlet of the valve,type has the convex valve plate and C type has the concave valve plate.The gas flow fields around the three wing valves of cyclone separator were simulated by computational fluid dynamics method to analyze erosion on the edge of the wing valve.The computational results indicate that type A valve can prevent particles from impingement on the valve plate with an angle of 30°～40°,which reduces erosion.Type B valve can form a stagnant area on the valve plate surface and reduce the direct impingement of particles on the valve plate.The internal surface of type C wing valve is subject to intensified direct impingement of gas flow because of its concave construction.The results of study show that both A type valve and type B valve have erosion-protection ability against impingement of particles.