影响FCC再生立管输送催化剂影响因素的分析

再生立管是FCC装置再生器和提升管反应器之间再生催化剂循环的输送管，其操作复杂性在于立管内催化剂的流态受多种因素影响。本文中在1.0Mt/a FCC装置上，通过测量立管改造前后不同操作条件时的轴向压力分布，考察再生立管输送催化剂的影响因素。生产运行结果表明，影响立管操作的主要因素包括催化剂密度和平均粒径、立管几何结构、滑阀安装位置、松动风性质和流量等；选用低密度催化剂和高黏度流化介质可以减小气泡尺寸，维持反应温度稳定；松动风流量应根据立管推动力、滑阀压降和反应温度及时调整，避免填充流。另外，立管结构和滑阀的安装位置对立管推动力影响较大，分析结果可供立管设计和装置改造参考。

Analysis of the factors affecting the conveyance of catalyst in the regenerated standpipe of FCCU

The regenerated standpipe is used for conveying the regenerated catalyst between the regenerator and the riser in FCC unit. The flow patterns of catalyst in standpipe are influenced by many factors which complicates the operation. The influence factors of conveying catalyst in standpipe were investigated by measuring the axial pressure distribution inside the standpipe at different operating conditions on a 1.0Mt/a FCC unit. The operation result showed that the main factors affecting the standpipe operation included the density and average particle size of the catalyst, structure of standpipe, the position of slide valve, the properties and flow rate of the aeration gas, et al. Low density catalyst and high viscosity aeration gas can reduce bubble size and maintain stable reaction temperature. Aeration gas rate should be adjusted in time according to the standpipe driving force and slide valve pressure drop to avoid packed bed flow. In addition, standpipe structure and the position of the slide valve had great influence on the standpipe driving force. The analysis made in this work can be used as reference for the standpipe design and the revampment of FCC unit.