前置烧焦罐式高效再生器催化裂化装置稳定性分析

STABILITY ANALYSIS OF FLUID CATALYTIC CRACKING UNIT WITH HIGHLY EFFICIENT REGENERATOR

对前置烧焦罐式高效再生器催化裂化装置反应-再生系统动态机理模型进行空间离散化，然后做线性化处理，得到了线性化状态空间模型．采用控制理论中的线性系统稳定性判据──特征值分析法分析反应-再生系统的稳定性．在控制二密相床和汽提段藏量的条件下，线性状态空间模型的全部特征值的实部在很宽的操作范围内都为负值，证明所研究的反应再生系统（线性化系统）是稳定的．

Stability analysis of fluid catalytic cracking units(FCCU)is an important part of operation analysis,process design and process control.For the FCCU with a highly efficient regenerator,the regenerator is composed of two stages that are characteristic of a fast fluidized bed and a bubble fluidized bed.Regenerated catalyst from the second stage of the regenerator circulates into the bottom of the first stage as well as the bottom of the riser reactor.The influence of the reactor and the regenerator on each other should be considened together in the stability analysis.Because of the complexity of the unit,the conventional technique of stability analysis such as heat generation and removal rates analysis for the CSTR with exothermic reaction is not suitable．After linearization of the dynamic mechanistic model of the FCCU with a highly efficient regenerator,stability theory is applied to the linear state space models obtained．Under the control of the inventories of the stripper and the second stage of the regenerator,the FCCU’s reactor/regenerator section is stable with in a wide range of operation conditions,because all the real component of eigenvalues of linear state space models are negative.