Industrial process control

What is Industrial process control?

Industrial process control or process control is a strategy used for monitoring and adjusting control variables of an industrial process to achieve desired outputs. This approach is used for improving performance and maintaining quality. 

One example of simple process control would be keeping the temperature of a room constant using an air conditioner and thermostat. 

A more advanced example of the process would be mixing two continuously flowing liquids in a set ratio. If one of the quids starts flowing at a greater speed, to maintain the ratio, the system will increase the flow of the second fluid as well. It is achieved by attaching a controller and valve with the pipes that are controlled by a PID-type controller. 

What are the types of industrial control systems?

Depending on the functionality and complexity, industrial control systems can be of several types. Here are some of the most common ones used across different industries. 

1. Distributed Control System (DCS): DCS is an industrial control system that works in a distributed manner where processes are controlled individually. 

2. Industrial Automation and Controls (IACS): It is an infrastructure that allows transferring of data and information safely and establishing communication between devices. 

3. Supervisory Control and Data Acquisition (SCADA): It is a computerized system that is capable of gathering and processing data and applying operational controls remotely. 

4. Human Machine Interface (HMI): These are hardware and softwares that help in the communication and exchange of information between human operators and machines. 

5. Remote Terminal Unit (RTU): It is a microprocessor based electronic device that is used in industrial control systems to connect different hardware to DCSs or SCADA. 

6. Programmable Automation Controllers (PACs): These are a type of automation controller that follows high-level instructions. They are used in a variety of sectors, especially those that have critical ICS infrastructure. 

7. Programmable Logic Controller (PLC): It is a control system that comprises a user-programmable memory for storing instructions which it implements to gather information and give outputs accordingly. 

8. Intelligent Electronic Devices (IEDs): They are electronic components (similar to a regular circuit control) with a microprocessor and the ability to communicate using Feildbus, real-time Ethernet, etc. 

What are the industrial applications of process control systems?

Process control systems are mainly used for making the processes more energy efficient and consistent. Here are some industrial applications of process control systems. 

• Chemical processing: Process control systems are used in chemical processing to maintain the desired chemical composition and properties of a product. For example, they can be used to control the temperature, pressure, and flow rate of a chemical reaction.
• Manufacturing: Manufacturers use process control systems to maintain the desired quality and consistency of a product. For example, they can be used to control the speed of a machine, the temperature of a furnace, or the amount of material used in a process.
• Power Generation: In power plants, it is used for maintaining efficiency and safety. For example, they are utilized to control the temperature of a boiler, the pressure of a turbine, or the flow rate of steam.
• Water Treatment: In water treatment facilities, process control systems are used to ensure that the water meets the desired quality standards. For example, they are used to control the pH of the water, the amount of chlorine in the water, or the turbidity of the water.
• Food Processing: in food processing, it is used for maintaining the safety and quality of the food products. They are used to control the temperature of a cooking process, the pH of a food product, or the amount of time a food product is stored.