SBR Sewage treatment plant automation using PLC and SCADA

Abstract

Today's never-ending industrial expansion and the sharp rise in urban pollution have led to environmental and water contamination. The industrial sewage water gets mixed with streams, ocean and ponds etc. that causes several ailments in living things. Proper treatment of sewage can prevent these problems. Sewage treatment is the process of removing contaminants from industrial/domestic wastewater. Physical process (such as filtration, sedimentation and distillation), chemical processes (such as flocculation and chlorination) and biological process (slow sand filters or biologically active carbon) are used to remove contaminants so that water becomes safe enough to get released into the environment. By using these sewage processes we can not only avoid the diseases but also we can recycle the industry wastewater (sewage process) for further uses (garden, car cleaning, etc.). There are conventional methods for sewage treatment, which occupies more spaces as well as involve higher constructive cost. The activated sludge process is modified by the "fill and draw" Sequencing Batch Reactor (SBR). The complete treatment procedure takes place in one tank as opposed to separate tanks for each process. The benefits include less expensive plant construction due to tank reduction and smaller footprint compared to alternative treatment options. This paper aims to monitor and automate various stages of sewage treatment carried through sequencing batch reactor. In general, industrial automation refers to the use of technology for process control in a variety of operations, including chemical and petrochemical, power, iron, and steel, food and beverage, waste water treatment, and other plants. One of the main needs that reduces the need for labour is plant automation. Currently, SCADA systems and programmable logic controllers are widely employed in industry. In order to improve the efficiency of the sewage treatment process, the application of PLC is investigated in this study.