Plantwide Control System Design and Performance Evaluation for Ammonia Synthesis Process

The emphasis on process economics in modem chemical plants has led to the increased use of material recycle and energy integration that significantly alter process dynamics and add complexity As a result, many plantwide control (PWC) methodologies have emerged However, there are very few comparative studies to evaluate the effectiveness of alternate methodologies In this study, a PWC structure for the ammonia synthesis process is developed using the integrated framework of simulation and heuristics [Konda et al Ind Eng Chem Res 2005, 44, 8300-8313], which is then compared with that developed by Araujo and Skogestad [Araujo and Skogestad, Comput Chem Eng 2008, 32, 2920-2932] using the self-optimizing control procedure The different control structures are evaluated in a comprehensive manner including assessment of the dynamic performance and steady-state profit