Research Of The CASS Process Automatic Control System Of Sewage Treatment

Guangxi is the largest sugar producing area in China. The production of sugar accounts for about60percent of total output. With the rapid economic development, a great demand for sugar is increasing and the sugar industry will have a bright prospect in China. However, it has been a "famous pollution industry" for a long time, with the further development of the sugar industry, the sewage emission will be continuously increasing, which is seriously harmful to the environment and human’s physical and mental health. Therefore, it is significant to research and develop an automatic sewage disposal system which is suited to the characteristics of sugar industry and solves the problem of sewage disposal.In this thesis, a development of a CASS process automatic control system of sewage treatment is made, which takes the Second Sugar Mill of Guangxi Tiandong Nanhua Sugar Industry Limited Liability Company as a background. The thesis focuses on the description of the selection of hardware, the selection of development software, the development of the monitoring program and the system installation and the debugging process of the system. The control system mainly consists of a industrial personal computer, a PLC, a communication module and various detection instruments and equipments, and mainly implements the detection of various parameters such as system liquid level, pressure value and temperature in the process of sewage disposal and the control of some implemental equipments such as pumps, fans and valves. In the system, the FX2N-serial PLC made by Mitsubishi Corporation is chosen as the core control unit, the GX Developer Version8.34is selected as the development software for PLC, and the Kingview is utilized as the software of developing host computer monitoring program.In the thesis, the detailed description of the installation and debugging of the system is also made, of which the installation and connection of various electric equipments, compilation and modification of PLC programs, industrial setting of configuration monitoring and some problems in the process of debugging or operation are included.The CASS process of sewage treatment control system is characterized by friendly human-computer interface, easy utilization and operation. Since it was adopted in the Second Sugar Mill of Yangpu Nanhua Tiandong, the system has been running stably and reliably, the various equipments has been in good condition, and all the specifications satisfy the requirements of the design and the operation.