ACS219 Process Control

Module Description (subject to change)

Process control is the study of regulating the conditions of a process in order to obtain a stable process and to generate high quality products efficiently, economically and safely. This module covers modelling and analysing various control system behaviours, including first order and higher order systems, with closed and open loops. The application of control systems to various chemical processes and units will be included.

Credits: 15 (Autumn Semester)

Pre-requisites:

Module Leader

PS
Dr Payam Soulatiantork
Email: p.soulatiantork@sheffield.ac.uk
Amy Johnson Building

If you have any questions about the module please talk to us during the lectures or the labs in the first instance. It is likely that other students will learn from any questions you ask as well, so don’t be afraid to ask questions.

Outside of lectures please contact me via email, or drop in to see me.

Learning Outcomes

Learning Outcomes

By the end of the module students will be able to:

  • Have proficiency with Laplace transforms as a tool for analysing dynamic behaviour and feedback loops for linear systems;
  • Determine from heat and/or mass balance considerations the strategic variables of a process unit and hence determine appropriate dynamic models;
  • Describe simple process dynamics in terms of gain, time constant, dead-time and damping;
  • Describe the step responses of first order system and evaluate links between behaviour and model parameters;
  • Describe the step responses of second order system in terms of damping factor and natural frequency;
  • Develop a transfer function model of several different simple chemical processes from first principles. Linearise the models and determine their responses to simple inputs such as steps;
  • Design a single loop feedback control law such as a PI controller;
  • Describe and analyse a conventional feedback control loop in block diagram form;
  • Ability to analyse open and closed loop stability and performance for simple processes;
  • Be aware of classical methods of controller tuning methods and more modern tuning and loop health monitoring tools;
  • Demonstrate an awareness of how an understanding of process dynamics and control has an impact on the design and selection of plant components;
  • Use their knowledge of the process to be designed to select the appropriate control strategy;
  • Identify, select and position different instruments appropriately within a control loop;
  • Design and analyse control schemes for common process units - knockout drums, ball mills, cooling towers, simple distillation tower. Including what doesn’t need to be controlled;
  • Identify key process variables and design appropriate control systems for these;
  • Identify basic control systems as layers of protection.
Syllabus

Syllabus

This module includes these topics:
Linear systems modelling of simple chemical processes
Laplace and inverse Laplace
1st and 2nd order responses
Transfer functions and block diagrams
System behaviours and analysis of system performance
Introduction to feedback
PI compensation
Use of MATLAB
Advanced control strategies
Process control applications
Instrument selection

Teaching Methods

Learning and Teaching Methods

NOTE: This summary of teaching methods is representative of a normal Semester. Owing to the ongoing disruption from Covid-19, the exact method of delivery will be different in 2020/21.

Lectures: 36 hours
Tutorials: 18 hours
Labs: 8 hours
Project work: 8 hours
Independent Study: 80 hours

Teaching Materials

Learning and Teaching Materials

All teaching materials will be available via MOLE and a university shared server (accessible via MUSE and on the main network).

Assessment

Assessment

Formal exam (40%) 2 hrs in Autumn exam period.

Coursework (30%)

Blackboard (MOLE) quizzes (20%)

Practicals (10%)

Feedback

Feedback

This module has regular tutorials in a laboratory where students can ask for feedback on their progress and raise any other concerns as well as seek more detailed feedback and assistance. This includes the opportunity to learn and develop MATLAB skills.

The lecturers are also responsive to requests for some generic feedback during lecture time, as time permits.

All the assignments are designed to give students fast quantitative feedback on their progress in that they allow students to assess explicitly to what extent they have mastered different topics.

Feedback is also available via the discussions board on MOLE.

A brief summary of how the class performed in the examination, both on the paper overall and on individual questions (on MOLE).

Student Evaluation

Student Evaluation

Students are encouraged to provide feedback during the module direct to the lecturer. Students will also have the opportunity to provide formal feedback via the Faculty of Engineering Student Evaluation Survey at the end of the module.

You can view the latest Department response to the survey feedback here.

Recommended Reading

Recommended Reading

Recommended background reading (especially introduction chapters):

  • Seborg, D.E; Edgar, T.F; and Mellichamp, D.A. (2003), Process Dynamics and Control, Wiley [available in Information Commons, 660.284(S)]
  • Roffel, B. and Betlem, B. (2006), Process Dynamics and Control: modelling for control and prediction, Wiley, [available in Information Commons, 660.2815(R)]
  • Nise, N.S. (2011), Control systems engineering, 6th Edition, Wiley [available in Information Commons & St. George’s Library, 629.8(N)]
  • Ogunnaike, B.A. and Ray, W.H. (1994), Process dynamics, modeling and control, Oxford University Press [available in Information Commons & St. George’s Library, 660.2815(O)]
  • Coughanowr, D.R. (1991), Process systems analysis and control, 2nd Edition, McGraw-Hill [available in St. George’s Library, 660.284(C)]
  • Luyben, W.L. (1990), Process modeling, simulation and control for chemical engineers, 2nd Edition, McGraw-Hill [available in St. George’s Library, 660.284(L)]
  • Stephanopoulos, G. (2006), Chemical process control: an introduction to theory and practice, Prentice Hall [available in Information Commons, 660.281(S)]