Sequence of Presentation

1.Why Process Control?

2 What to Control?2.What to Control?

3.Role of Sensors and Instruments

4.Modes Of Control Systems

5.Basics of Feedback Control Systems5.Basics of Feedback Control Systems

6.Examples of Servo Control Systems

7.Conclusions

1. Why Process Control ?

1.Safety of Equipment and Personnel

2 Productions Specification of quality & 2.Productions Specification of quality & quantity

3 Operational Constraints 3.Operational Constraints

4.Observe Environmental and Country LLaws

5.Economics

Control Objectives

1. Safety of Equipment &

Give example

q ppersonnel

2. Production Specification of

VaporProduct

T1 T5

T6 PC

quality & quantity

3. Operational

T1

F1

T2

T4

T5

T3 L1

Feed

Constraints

4. Environmental Regulations

LiquidF3F2

A15. Economics

LiquidproductSteamProcess

fluid L. Key

A1

Safety of Equipment & Personnel

1. Safety of Equipment & personnel

High pressurein drum is dangerous

VaporT6 PCpersonnel

2. Production Specification of quality &

VaporProduct

T1 T2 T5

T6 PC

Feedquality & quantity

3. Operational Constraints

F1

T2

T4 T3 L1Constraints

4. Environmental Regulations

5 E iLiquid

P

F3F2A15. Economics productSteamProcess

fluid L. Key

Control Objectives

1. Safety of Equipment &

Give example

q ppersonnel

2. Production Specification of

VaporProduct

T1 T5

T6 PC

quality & quantity

3. Operational

T1

F1

T2

T4

T5

T3 L1

Feed

Constraints

4. Environmental Regulations

LiquidF3F2

A15. Economics

LiquidproductSteamProcess

fluid L. Key

A1

Safety of Equipment

1. Safety of Equipment &

lVaporT6 PC

No flow could damage the pump

personnel

2. Production Specification of

lit &

Product

T1 T2 T5F dquality &

quantity

3. Operational Constraints

F1 T4 T3 L1

Feed

Constraints

4. Environmental Regulations Liquid

d tSteamProcess

F3F2A1

5. Economics productSteamProcessfluid L. Key

Smooth Production Rate

1. Safety of Equipment &

Always keep the production rate smoothq p

personnel

2. Production Specification of

VaporProduct

T5

T6 PCrate smooth

quality & quantity

3. Operational

T1

F1

T2

T4

T5

T3 L1

Feed

Constraints

4. Environmental Regulations F3F2

L1

5. Economics LiquidproductSteamProcess

fluid L. Key

A1

Quality Assurance

1. Safety of Equipment &

VaporT6 PC

Give Example

personnel

2. Production Specification of

VaporProduct

T1 T2 T5

T6 PC

quality & quantity

3. Operational

T1

F1

T2

T4

T5

T3 L1

Feed

Constraints

4. Environmental Regulations

LiquidF3F2

A15. Economics

LiquidproductSteamProcess

fluid L. Key

A1

Quality Assurance

1. Safety of Equipment &

Achieve L.Key by adjusting the heatingEquipment &

personnel

2. Production Specification of

VaporProduct

T6 PCthe heating

Specification of quality & quantity

3 Operational

T1

F1

T2

T4

T5

T3 L1

Feed

3. Operational Constraints

4. Environmental Regulations

F3F2

L1

Regulations

5. EconomicsLiquidproductSteamProcess

fluid L. Key

A1

Observe Environmental and Other Regulations

1. Safety of E i t &

Never release hydrocarbons

Equipment & personnel

2. Production S ifi ti f

VaporProduct

T5

T6 PCy

to atmosphere

Specification of quality & quantity

3 Operational

T1

F1

T2

T4

T5

T3 L1

Feed

3. Operational Constraints

4. Environmental Regulations Li id

F3F2Regulations

5. EconomicsLiquidproductSteamProcess

fluid L. Key

A1

Economics

1. Safety of E i t &

Give Example

Equipment & personnel

2. Production S ifi ti f

VaporProduct

T6 PC

Specification of quality & quantity

3 Operational

T1

F1

T2

T4

T5

T3 L1

Feed

3. Operational Constraints

4. Environmental Regulations

F3F2

T3 L1

Regulations

5. EconomicsLiquidproductSteamProcess

fluid L. Key

A1

Economics

1. Safety of Equipment & personnel

2. Production Specification of

Give Example

quality & quantity

3. Operational C iConstraints

4. Environmental Regulations

5. Economics

2. What to Control ?

1.The Influence of External Disturbances (Suppress Them)Disturbances (Suppress Them)

2.Ensure Stable Operation

(Avoid Unsteady State)

3 O ti i d O ti 3.Optimized Operation

(Control Operating Costs)(Control Operating Costs)

Suppress the Influence of External Disturbances

Disturbances?

Ensure Stable Operation

Ensure Stable Operation (cont’d)

Optimized Operation (online)

Potential Stochastic Gains through effective Process Control

When we control a process, we reduce the variability.

Potential Stochastic Gains through effective Process Control (Cont’d)

Variability is moved from controlled to manipulated variable!

Potential Stochastic Gains through effective Process Control (Cont’d)

What statistics l l tcan we calculate

from this data?

How do we relate variability to process performance?performance?

Potential Stochastic Gains through effective Process Control (Cont’d)

Process performancepefficiency, yield, production rate, etc. It measures performancemeasures performance for a control objective.

Calculate the processperformance using the distribution not thedistribution, not the average value of the key variable!

Examples of feedback system

A typical instrument has three components:

3. Role of Sensors and Instruments

A typical instrument has three components:

A SensorA SensorA ModifierA Display (Or transmitting arrangement)

Sensors feel the condition and originate the i l f ll d b difi ti d signal followed by modification and

amplification for effective display or transmission.

Instruments are the eyes of engineer/

Comment on Sensors and Instruments

Instruments are the eyes of engineer/ operator that can see & feel the intense process variable inside the vessels

Accordingly the measurements should be reliable and as close to actual condition as reliable and as close to actual condition as possible with reasonable costs.

Process control go hand in hand “If you cannot measure you cannot control!”

Example of Temperature Control (Heat exchanger)

4. Modes of Control Systems

Feedback Control Systems (Regulatory)Feedforward Control Systems(Servo, Tracking)Sequential Control SystemDistributedIntegratedIntegrated

Modes of Implementation

PneumaticElectronicDigital

Basics of feedback control system

Example of Composition Control

Examples of feedback system

Examples of feedback system

Where is Control Done?

Examples of feedback system

Examples of feedback system

Control System Implementation

Analog and local ControlAnalog and local Control

Microprocessor based Distributed ControlMicroprocessor based Distributed Control

Field Bus based Distributed Control System(State of art with ever growing capabilities

and features!)

Control Systems Implementations In Industry

Control Systems Implementations In Industry

Control Systems Implementations In Industry