Universidade Nova de Lisboa

Courses Catalogue

We welcome you to explore NOVA’s academic offerings.
Our catalogue provides a description of the courses offered at NOVA as well as useful information about our Schools.

more info Courses Catalogue

Faculdade de Ciências e Tecnologia

Instrumentation and Process Control

Code

7342

Academic unit

Faculdade de Ciências e Tecnologia

Department

Departamento de Química

Credits

6.0

Teacher in charge

Mário Fernando José Eusébio

Weekly hours

4

Total hours

72

Teaching language

Português

Objectives

Students are provided a modern view of process control engineering in the context of this current technology, with emphasis on its application to the chemical process industry. The major steps of the implementation of process monitoring, and analogical and digital control of chemical processes are presented and discussed. Students have access to an Armfield PCT40 system for hands-on experience with measurements instruments, real-time computers, and experimental process dynamics and control problems.

Prerequisites

Basic knowledge of mathematical analysis including elementary notions of Laplace transforms.

Basic knowlwdge of mass, energy and momentum tranfer and also mass and energy balances.

Subject matter

 

  • Process control
  1. Economical and technical justification for process control in the chemical industry
  2. Elements comprising a control system: process, measuring devices, transmitters and transducers, controller, actuator
  3. Mathematical modelling of chemical processes
    1. Classical modelling and model linearization
    2. Empirical modelling and parameter estimation
    3. Degrees of freedom of a process
  4. Laplace transforms
    1. Transfer function
    2. Block diagram
  5. Dynamics of linear systems
    1. First-order systems
    2. Second-order systems
    3. Higher-order systems
  6. Feedback control systems
    1. ON/OFF control
    2. Proportional (P) control
    3. Proportional-Integral (PI) control
    4. Proportional-Integral-Derivative (PID) control
  7. Dynamics of feedback control systems
    1. Block diagram
    2. Response of closed-loop control
    3. Servo-mechanism problem
    4. Regulation problem
    5. Impact of proportional, integral and derivative control actions
    6. Response of the controlled system to a step change in the set-point
    7. Response of the controlled system to a step change in the load variable
    8. Effect of combined PI and PID actions
  8. Cascade control
  9. Feedforward control
  10. Combined feedback feedforward control
  11. Time-delay systems
  12. Inverse-response systems
  13. Practical rules for controller selection
    1. Efect of control parameters (gain and time constants) on system response
    2. Controller tunning: empirical rules, Ziegler-Nichols method, Cohen & Coon method
  14. Digital control
    1. Digital signal transmission
    2. A/D and D/A conversion
    3. Analog and digital filters
    4. Digital PID control
  • Instrumentation
  1. Control valves
    1. Elementos constituintes
    2. Types of plugs
    3. Dynamics
    4. Flow capacity characteristics
  2. Temperature measurement
    1. Thermocouples
    2. Resistance thermometers
  3. Pressure measurement
    1. Manometers
    2. Diaphragm elements
    3. Transducers
  4. Flow-rate measurement
    1. Medidores da taxa de caudal
    2. Differential-pressure devices: orifice plates, venturi flow nozzle, Pitot tube
    3. Rotameters
  5. Liquid-level measurement

Bibliography

 

  • B. A. Ogunnaike, W. H. Ray. Process Dynamics, Modelling, and Control. Oxford University Press, 1994
  • D. M. Considine. Process Instruments and Control Handbook. McGraw Hill, 1974
  • J. W. Dally, et al. Instrumentation for Engineering Measurements, John Wiley & Sons, 1984
  • D. E. Seborg, T. F. Edgar, D. A. Mellichamp. Process Dynamics and Control. John Wiley & Sons, 1989
  • G. Stephanopoulos. Chemical Process Control - An Introduction to Theory and Practice. Prentice/Hall, 1984

Teaching method

In theoretical and practice classes concepts are illustrated through the use of transparencies and slides. Students have access to a textbook which covers the theoretical contents of the course. Many of the theoretical concepts are elaborated through the presentation and discussion of case studies. Students have access to an Armfield PCT40 system for hands-on experience with measurements instruments, real-time computers, and experimental process dynamics and control problems.

Evaluation method

The evaluation includes lab sessions and the corresponding reports and discussion. If the student succeeds there is also a written exam.

The final grade is 20%of the grade obtained in the labs + 10% continuous evaluation during classes +70% of the grade obtained in the exam  (which has to be >=9.5). The grade scale is 0-20. For grades greater than 16 points the student may be asked to carry out an oral examination.

 Any student involved in fraud fails. In case of doubt the student may be asked to carry out an oral examination.

Courses