MICROCONTROLLER-BASED CONTROL SYSTEM OF BIOLOGICAL WASTEWATER TREATMENT

Abstract

Organic pollution disposal problems in wastewater treatment plants (wwtps) are solved by means of continuous activated sludge processing, in which sludge recycling and forced aeration secure a high efficiency treatment. Treatment of municipal or industrial .waste is an energy intensive process. The activated sludge aeration process is the biggest consumer of electricity. Optimum control of the process requires an accurate and reliable dissolved oxygen (DO) measurement on a ontinuous basis. In the activated sludge, microorganisms (MO) are mixed thoroughly with the organic matter so that they can grow and stabilize the organic matter. As the microorganisms grow and are mixed by the agitation of the air, the individual organisms clump together (flocculate) to form an active ass of microbial floc called activated sludge. The mixed liquor flows fro the aeration basin to a secondary clarifier where the activated sludge is settled. A portion of the settled sludge 1is returned to the aeration basin to maintain the proper food-to-MO ratio to permit rapid breakdown of the organic matter, some of it is wasted fro the aeration basin or from the returned sludge line