催化裂化装置立管-阀门系统设计及运行分析

立管-阀门系统是催化裂化（FCC）装置催化剂颗粒循环回路的下行流动部分。立管输送催化剂操作的复杂性在于立管内催化剂流态的多样性。介绍了工业FCC装置立管-阀门系统的设计方法、立管操作工况以及压降方程。在某1.0 Mt/a FCC装置上，以再生立管为对象，通过测量不同工况时再生立管的轴向压力分布和采集工艺参数的变化，分析立管内气固两相的流动方向、催化剂密度与速度分布。根据气固两相的流动特征将立管分为3个区，分别为负压差脱气段、负压差持气段和正压差窜气段。总结了半管流形成的原因以及阀门窜气对立管压力分布的影响，提出了再生立管结构优化方案。分析结果可为FCC装置立管-阀门系统的设计和操作调整提供理论支持。

DESIGN AND OPERATION ANALYSIS OF STANDPIPE-SLIDE VALVE SYSTEM IN FCC UNIT

The standpipe-slide valve system is the key component of the downstream flow of the catalyst particles cycle in FCC unit.The complexity of conveying catalyst operation in standpipe lies in the diversity of catalyst flow patterns in standpipe.The calculation method of standpipe-slide valve system in commercial FCC unit and pressure drop equation was introduced.On a 1.0 Mt/a FCC unit,the flow direction,catalyst density and velocity distribution of gas and catalyst particles in the standpipe were analyzed by measuring the axial pressure distribution of the standpipe and recording the processing parameters in different operating conditions.According to the flow characteristics of the gas and catalyst particles,the standpipe was divided into three sections,namely,the negative differential pressure degassing section,the negative differential pressure holding gas section and the positive differential pressure gas leakage section.The reasons causing the formation of half pipe flow and effect of gas leakage from slide valve on standpipe pressure distribution were summarized.The results provided theoretical support for the design and operating adjustment of the standpipe-valve system in FCC unit.