催化裂化主分馏塔与稳定塔的关联性分析及稳定塔的控制

INTERACTION ANALYSIS BETWEEN MAIN FRACTIONATOR AND STABILIZER OF FCCU AND STABILIZER CONTROL

研究分析了催化裂化装置的主分馏塔与稳定塔之间操作控制的关联性。基于状态反馈预测控制概念,根据装置的操作控制特点及现有测点情况,建立用于稳定汽油饱和蒸气压实时控制的简化状态空间数学模型。使用实测状态变量反馈和计算换热量设计预测控制前馈的方法,减弱主分馏塔对稳定塔操作控制的影响,提高控制系统的控制性能及抑制干扰能力;对预测控制系统进行在线计算和修正,改善和提高了控制系统的综合性能。稳定塔状态反馈预测控制系统在多套催化裂化装置DCS层上成功实施,表明了数学模型设计的有效性。

The operation and control interaction analysis between main fractionator and stabilizer of FCCU was studied. Based on the predictive control concept of the state feedback model, and according to the plant operation features and the existing sensors, a simplified state space model was established for the real time control of Reid vapor pressure of the stabilized naphtha. By using the state variable feedback control and computing the heat exchange quality to design the predictive feed forward control of the model, the interaction effect from the main fractionator to the stabilizer can be reduced; and the control performance, robustness and disturbance rejection ability were raised. Through on-line calculation and revision of the predictive control system, comprehensive performance of the control system was improved. The Reid vapor pressure control system of the stabilizer was implemented in several different kind of DCS layers, and the model efficiency was proved.