Analysis of Wear Holes on Cone Wall of Cyclone Separator in FCC Unit
The cyclone separator in the regenerator of a 1.0 Mt/a fluid catalytic cracking unit had the wear holes on the wall during operation, as a result, the separation efficiency of cyclone separa-tor decreased, and a serious catalyst loss occurred. This paper analyszes the process of wear hole based on the wear model of gas-solid two-phase flow and the characteristics of gas-solid swirling flow field. Under the action of centrifugal force and gravity inside the cyclone separator, the catalyst gath-ers on the surface of the cyclone wall to form a downward spiral ash ring. When the spiral ash ring moves to the cone section, the swirling flow of the ash ring is accelerated and the spiral angle of the ash ring is reduced, forming a suspended rotary ash ring on the surface of the cone wall. At the same time, the particle concentration of the ash ring also increases, and the normal pressure on the cone wall is raised, resulting in enhanced friction and finally causing wear hole on the cone wall.