Chemical Engineering

Introduction: process control system, terms and objective of automatic process control, regulatory and servo control, transmission signal, control strategies. Mathematical tools: the Laplace transform, solution of differential equations using the Laplace transform, characterization of process response, response of first-order systems, response of second-order systems, linearization. First order dynamical systems: importance of process characteristics, mathematical modelling of processes, dead time, transfer function and block diagrams, chemical reactors, effects of process nonlinearities. Higher-order dynamical systems: non-interacting systems, interacting systems, response of high-order systems. Basic components of control systems, sensor and transmitters, control valves, feedback controllers. Design of single-loop control systems: the feedback control loop, stability of the control loop. Tuning of feedback controllers: quarter decay ratio response by ultimate gain, open-loop process characterization, tuning controllers for integrating processes, synthesis of feedback controllers. Root locus and frequency response techniques: analysis of feedback control systems by root locus, rules for plotting root locus diagrams, frequency response and stability. Cascade control: process examples, stability considerations, implementation and tuning of controllers. Ratio, override and selective control: computing algorithms, ratio control, override or constraint control, selective control. Feedforward control: the feedforward concept, block diagram design of linear feedforward controllers, lead/lag element, design of nonlinear feedforward controllers from basic principles, outline of feedforward controllers. Multivariable process control: loop interaction, pairing controlled and manipulated variables, decoupling of interacting loops, multivariable control vs. optimization, dynamic analysis of multivariable systems, design of plantwide process control.

For a successful learning, in-depth knowledge in mathematical analysis, thermodynamics for chemical engineering, machinery and design of unit operations of the process industry is mandatory.

N. Verdone. Sistemi di Controllo degli Impianti Chimici, Lectures notes (in italian), 2010. C.A. Smith, A.B. Corripio. Principles and Practice of Automatic Process Control, 3rd ed., Wiley (2005). D.E. Seborg, D.A. Mellichamp, T.F. Edgar, F.J. Doyle. Process Dynamics and Control, 4th ed., Wiley (2017).

Course attendance is not mandatory. The organization of the teaching activities foresees, for each topic, the presentation of the theoretical aspects and the development of numerical exercises for the application of the learned concepts. Classroom activities to learn how to use the Scicos (Scilab) and Simulink (Matlab) simulators are planned.

Course attendance is not mandatory.

The examination consists in the solution of a practical control problem and in the verification of the knowledge of the principles of the theory of control. To pass the exam, the student must demonstrate that he/she has acquired sufficient knowledge of the problems related to the analysis and design of the control systems applied in the chemical industry. The assessment of the examination is based on the ability to apply the acquired concepts in the solution of practical problems and is also subject to the ability to explain concepts in a clear and accurate manner.

Course attendance is not mandatory. The organization of the teaching activities foresees, for each topic, the presentation of the theoretical aspects and the development of numerical exercises for the application of the learned concepts. Classroom activities to learn how to use the Scicos (Scilab) and Simulink (Matlab) simulators are planned.