EAT 449 ENVIRONMENTAL PROCESS CONTROL AND INSTRUMENTATION DR

EAT 449 ENVIRONMENTAL PROCESS CONTROL AND INSTRUMENTATION DR UMI FAZARA MD. ALI DR SALSUWANDA SELAMAT SCHOOL OF ENVIRONMENTAL ENGINEERING UNIVERSITI MALAYSIA PERLIS 2017/18

Outline for Introductory Notes REGISTERED STUDENT 31 for EAT 449 (as of Sept 5, 2017) HEA 01 : SYNOPSIS, LAB / EXPERIMENT COURSE OUTCOME, TEACHING PLAN REFERENCES CLASS SCHEDULE LAB/PBL GROUPING EVERYDAY EXAMPLES OF PROCESS CONTROL PHILOSOPHY OF PROCESS CONTROL SYSTEM MATLAB/SIMULINK LAPLACE TRANSFORM

What you have learned so FAR… 1. ? 2. ? 3. ? 4. ? 5. ? 6. ? 7. ? 8. ? 9. ? 10. ? 11. Industrial Training 12. FYP 13. Design

References: 1. J. B. Riggs and M. N. Karim “Chemical and Bio. Process Control”, 3 rd edition, Pearson International Edition (2007). 2. Coughanowr & Koppel, “Process System Analysis and Control”, Mc. Graw Hill, 1991 3. Stephanopoulos, G. , Chemical Process Control : An Introduction to Theory and Practice, Prentice Hall Inc. , New York, 1984 4. D. E Seborg, T. F Edgar, D. A Mellichamp, Process Dynamics Control, John Wiley and Son (2003) 5. T. E Marlin, “Process Control: Designing Processes and Control Systems for Dynamics performance, Mc. Graw Hill (2000)

EVERYDAY EXAMPLE OF PROCESS CONTROL Driving a vehicle (Manual Process Control) Objective: To keep the car in its lane on the road. The sensor is the person's eyes The Control Variable (CV) is the position of the car on the road. The Manipulated Variable (MV) is the steering wheel position The actuator (final element) can be thought of as the person's hands and arms that turn the steering wheel. The controller is the person driving (brain). Curves in the road are disturbances control.

Air conditioning in a classroom (Automatic Process Control) Objective: To keep the room temperature in its set point. The sensor is thermocouple The Control Variable (CV) is the room temperature. The Manipulated Variable (MV) is flow of cool air from refrigeration (air conditioning) unit The actuator (final element) can be air conditioner compressor The controller is the automatic controlling unit inside the air conditioner. Heat transfer/flowing into the room is disturbances control.

Temperature, Level and Flow in a stirred tank (Automatic or Manual Process Control) Objective: To keep the tank temperature, level and flow in its set point. The sensor is thermocouple and level sensor The Control Variable (CV) is the tank temperature, level and flow. The Manipulated Variable (MV) is flow of steam and flow of inlet liquid The actuator (final element) is control valve or human being The controller is the automatic controlling unit or human brain. Inlet temperature and inlet flow are disturbances control.

SPECIFIC EXAMPLE IN ENV ENG Batch Bio-reactor Objective: To keep the temperature, biomass, p. H and DO in its set point. The sensor are thermocouple, p. H meter, turbidity meter, DO meter The Control Variable (CV) are temperature, bio-mass, p. H and DO The Manipulated Variable (MV) are flow of air, turbidity, heat supply, acid or base supply The actuator (final element) can be …………………. The controller is the automatic controlling unit …………………. . . …………. is disturbances control.

Activated Sludge Process Objective: To keep the temperature, biomass, p. H and DO in its set point. The sensor are thermocouple, p. H meter, turbidity meter, DO meter The Control Variable (CV) are temperature, bio-mass, p. H and DO The Manipulated Variable (MV) are flow of air, turbiidity, heat supply, acid or base supply The actuator (final element) can be control valve The controller is the automatic controlling unit on the activated sludge unit Waste flow rate is disturbances control.

PHILOSOPHY OF PROCESS CONTROL SYSTEM CONTROLLING SYSTEM Input COMPARATOR Set Point + - e CONTROLLER Comparator calculate Error (Set Point – Output) Controller decide corrective action that should be done by actuator ACTUATOR SENSOR PROCESS Sensor detects process variable FEEDBACK CONTROLLER Output

EXAMPLE OF PROCESS CONTROL SYSTEM FAi CONTROL SYSTEM Liquid level COMPARATOR h CONTROLLER Level sensor sending signal to comparator Error correction by control system FAo ACTUATOR Control Valve opening

MODELING IN PROCESS CONTROL SYSTEM FAi Liquid level h FAo = k. h Surface Area A Output Input Differential Equation

TRANSFER FUNCTION = L. T Output / L. T Input Laplace Transform Kp Time Constant =0 Output

TRANSFER FUNCTION IN PROCESS CONTROLLER ACTUATOR Input + PROCESS Output - SENSOR

Comparison of Driving a Car and Control of a Heat Exchanger Actuator: Driver’s arm and steering wheel vs. Control valve n Controller: the driver vs. an electronic controller n Sensor: the driver’s eyes vs. thermocouple n Controlled variable: car’s position on the road vs. temperature of outlet stream n

Laplace Transform