Operating an ideal heat integrated distillation column with different control algorithms

Abstract

The operation of an ideal heat integrated distillation column is addressed. Five control strategies, namely, single loop composition control system, multi-loop composition control system, multivariable internal model control (IMC) system, modified multivariable IMC control (MIMC) system and nonlinear process model based control (NPMC) system, are design and applied to the process. Simulation results demonstrate that all the control systems are capable of keeping both end products on their specifications. The NPMC is the best one in the operation of the ideal HIDiC. It can very smoothly realize setpoint transition and efficiently counteract external disturbances. The MIMC ranks the second for the regulatory responses to feed composition disturbances have relative longer setting time. The next comes to the multi-loop composition control system. Although it works well for the operation of the ideal HIDiC, it produces relative larger oscillations and longer setting time in the system responses. The IMC can not compete with the multi-loop composition control system because it is extremely sensitive to operating condition changes. The single-loop composition control system is the worst one for the responses of the uncontrolled product is extremely sluggish.