AUTOMATION OF SEWAGE TREATMENT PLANT

Abstract

In the whole world water is becoming an increasingly scarce resource. Utilities are forced to consider any sources of water which might be used economically and effectively to promote further development as water is the backbone for growth and development of any country. Expansion of urban populations and increased coverage of domestic water supply and sewerage give rise to greater quantities of municipal wastewater. Properly planned use of wastewater alleviates surface water pollution problems and not only conserves valuable water resources but also takes advantage of the nutrients contained in sewage to grow crops. The nitrogen and phosphorus content of sewage might reduce or eliminate the requirements for commercial fertilizers. So the sewage treatment plants (STPs) have to be installed and operated in optimized ways having higher efficiency. It is shown in this paper that these STPs not only solves the problem of water pollution but also helps in alleviating water scarcity issues , need of fertilizers in irrigation uses and somewhat energy generation. The degree and importance of automation at wastewater treatment plants (WWTPs) have increased with the development of technology and tightening of treatment requirements. It has been found that automation not only reduce manpower requirement but also increases efficiency of plant, enhances reliability and accuracy of plant, maximize profitability, improves safety and ensure quality. The control system designed, not only governs all elements of performance of the plant, but also oversees its proper functioning. It also has a human-machine interface with a daily working and emergency program, accompanied by an information system supported by records and alarms to facilitate human decisions making if it were necessary. The proposed solution, not only increases the reliability and safety of the process with respect to plants or other type semi-automatic operation, but also reduces costs by improving process efficiency and minimizes costs in maintenance and monitoring