In the industrial sector, there are corresponding control systems for various physical quantities encountered in production processes such as sewage, air purification, and mechanical and electrical equipment manufacturing, including temperature, flow rate, pressure, speed, position, frequency, emission values, etc. On this basis, a digital control system with better control performance and higher degree of automation has been established through the use of digital computers, as well as a process control system with dual functions of control and management. The application in sewage treatment includes the ability to monitor various stages of sewage treatment in real-time. Management personnel can use data analysis to accurately regulate the sewage treatment process, automatic control systems, and automatic operation systems for air purification in surface treatment factories.