A New control structure for tert-amyl methyl ether production using reactive distillation

Area of Science:

• Chemical Engineering
• Process Control
• Reactive Distillation

Background:

• Reactive distillation is a key technology for producing tert-amyl methyl ether (TAME).
• Conventional PI controllers exhibit oscillatory behavior in TAME production, necessitating improved control strategies.
• Benchmark studies by Luyben (2005) provide a basis for evaluating new control structures.

Purpose of the Study:

• To develop and evaluate new control structures for TAME production using reactive distillation.
• To address and eliminate oscillatory behavior observed with conventional PI controllers.
• To compare the performance of PI and novel NMSS-PIP controllers.

Main Methods:

• Steady-state and dynamic simulations using Aspen® simulator.
• Modification of the process flow sheet to improve dynamic performance.
• Application of Non-minimal state space with proportional integral plus (NMSS-PIP) controller.
• System identification using the refined instrumental variable (RIV) method to obtain state matrices.

Main Results:

• Conventional PI controllers resulted in oscillatory behavior.
• Modified process flow sheet improved dynamic performance but did not completely eliminate oscillations.
• The NMSS-PIP controller completely eliminated process oscillations.
• NMSS-PIP demonstrated smoother responses and better settling times compared to PI control.
• ITAE criterion decreased by approximately 20% for PI and 88% for PIP control in the modified process.

Conclusions:

• The developed NMSS-PIP controller offers superior performance for TAME production via reactive distillation.
• The modified control structure with NMSS-PIP significantly enhances process stability and efficiency.
• This research provides a robust control solution for reactive distillation processes, reducing oscillations and improving response characteristics.