Abstract: This paper proposes a design scheme for a wastewater treatment control system based on the PROFIBUS-DP bus. The technical characteristics of the PROFIBUS-DP bus are briefly introduced, and the design concept and implementation process of the control system's hardware and software are elaborated in detail. Some technical issues that need attention during system debugging are also presented.
Keywords: Profibus-DP; wastewater treatment system; PLC; configuration software
1 Introduction
Wastewater treatment is receiving increasing attention in today's society, and it is essential in the paper industry. Ningxia Meili Paper Industry Co., Ltd. generates a large amount of wastewater daily, which, if allowed to flow into rivers and lakes, would inevitably cause severe environmental damage. The company has constructed a 150,000-ton wastewater treatment plant, which consists of two parts: an anaerobic wastewater treatment system and an aerobic wastewater treatment system. The wastewater treated by the system is rich in various nutrients and can be used to irrigate tens of thousands of acres of fast-growing forests planted by Meili Paper Industry Co., Ltd. The irrigation water can then be pumped out and reused by the paper mill after infiltration through the sand. Meili Paper Industry Co., Ltd. is located on the edge of the Tengger Desert. The fast-growing forests irrigated by the nutrient-rich wastewater not only bring considerable economic benefits to the company but also play an immeasurable role in preventing desertification. Therefore, the development of a wastewater treatment and control system is imperative.
In view of the characteristics of the field control equipment of the sewage treatment plant being relatively dispersed and far apart, the control system is designed with advanced Profibus emens industrial configuration software fieldbus technology and WinCC (IPC) and programmable controller (PLC) as well as remote I/O. The system is flexible, scalable, stable in operation and low in cost.
The PROFIBUS bus standard is based on the ISO/OSI Open Systems Communication Model, also known as the EN50170 European Fieldbus standard. It is defined by the Automated CIF (Automatic Information Specification). PROFIBUS is used for device-level control systems and distributed communication. It offers good real-time performance, with data transmission rates ranging from 9.6 Kbit/s to 12 Mbps. Data transmission technology uses RS485, and the transmission medium is shielded twisted-pair cable or wire, which significantly reduces wiring work, avoids signal interference, and makes the system more reliable. PROFIBUS excels in openness, interchangeability, and interoperability, and its industrial performance is outstanding.
For details, please click: Wastewater Treatment System Based on PROFIBUS-DP Bus
