(486s) Dynamic Modeling and Control of An Industrial Multistage Flash Desalination System | AIChE

(486s) Dynamic Modeling and Control of An Industrial Multistage Flash Desalination System

Authors 

Lee, J. - Presenter, Chang Gung University
Wang, G. - Presenter, Chang Gung University


The water desalination industry was started early in the 20th century and true expansion and spread of this industry occurred during the 1960s. It is known that multistage flash (MSF) and reverse osmosis (RO) technologies remain the main standards in today's seawater desalination industry. To maintain the safe and smooth operation of desalination systems at their optimal conditions, an efficient and accurate process control system used in the plant is necessary.

This work tries to study the dynamic modeling and process control problems for an industrial multistage flash plant. By using the powerful commercial process design simulators, the steady-state and dynamic simulations of this MSF desalination process are first studied. The experiences gathered are then utilized to develop the overall process flow sheet for this industrial large-scale MSF plant. Moreover, the important design parameters and optimal operating conditions for the proposed MSF process flow sheet are further defined from relative studies. For this overall MSF system, suitable control structures and proper PID controller parameters are then determined by RGA analysis and model identification techniques. In addition, cascade and feedforward control strategies are then introduced into the overall control loops to improve control performance. Finally, the steady-state and dynamic simulation results demonstrate the overall operation and control performance of the proposed large-scale MSF plant.