Abstract
With the development of our national economy and the people’s living
standards improved, people need higher quality and better environmental
requirements. As a result, solving the problem of water pollution and
completing the sewage treatment are the important condition that protects the
ecological environment and creates the comfortable living environment.
After reading a lot of technical reference, researches the actual sewage
disposal process in the filtration process, and sewage filter achieves the
automatic control by PLC according to the technological characteristics of the
process and requirements. Second, completes the system hardware and
software design in accordance with the principles and steps of control system
design. The control system design can is divided into the sewage settling tank,
filters and filter backwash in the choice of the Omron series PLC. Designed
PLC control system is expected to achieve water filtration system, saving
human and material resources.
This dissertation has three major components by the filtration process
technology, selection of hardware and software design. Filtering process
introduces some of the major filtering process flow works, process
characteristics and control requirements. Hardware selection section details
the selection of PLC modules, input and output points to determine, the
distribution of input and output address. Software design discusses some of
the major PLC internal address allocation, program flowchart and LD.
Key words: Filtration process; Subside; Backwash; PLC; LD
