Dynamic Modeling, Efficiency Analysis, and Hierarchical Control of Industrial Airborne Pulp Dryers

A first-principles dynamic modeling and control framework for industrial airborne pulp dryers is presented. The proposed nonlinear model integrates airflow, pressure, moisture, psychrometric, heat-transfer, and fan electromechanical dynamics within a unified state-space formulation. An efficiency analysis framework incorporating overall efficiency, thermal efficiency, fan efficiency, and specific moisture evaporation ratio (SMER) is also developed. To enhance process performance, a hierarchical DSM-based control architecture combining cascade and non-cascade control loops with supervisory optimization is proposed. The model was implemented in MATLAB/Simulink and evaluated under thermal, compositional, hydraulic, and mechanical disturbances. Simulation results demonstrated accurate moisture regulation, effective disturbance rejection, and favorable energetic performance, achieving an overall efficiency of 85.8%, a thermal efficiency of 86.9%, and an average SMER of 1.39 kg/kWh. To the best of the authors' knowledge, this work represents one of the first comprehensive dynamic modeling and control studies of industrial airborne pulp dryers and provides a proof-of-concept platform for future digital-twin, advanced control, and energy-optimization applications.