Masu, SmarandaSmarandaMasuUruioc, StelaStelaUruiocAlbulescu, MarianaMarianaAlbulescuJurj, Nicoleta LuminitaNicoleta LuminitaJurjSavescu, ElenaElenaSavescuBorbely, BrigitteBrigitteBorbely2017-05-032017-05-032012978-963-306-165-7http://hdl.handle.net/123456789/988The 18th Symposium on Analytical and Environmental Problems with special emphasis on heavy metal ions as contaminants, 24 September 2012, Szeged, Hungary, Conference Proceedings, pp. 52-55The predominant organisms of the sludge determined the efficiency of the biological treatment with a high organic load in the plant. The alteration of activated sludge health determined the destruction of granular flocks and the forming of filamentous structures because of the filamentous bacteria or some fungi multiplication. The filamentous structure determines the swelling of the sludge and reduction of its capacity to decompose organic matter. Swelling of the sludge is determined by the dominance of bacteria belongings Zooglea genus which secrets abundant extracellular material with high degree of hydration. The most practical solution to revive the activated sludge in an excess aeration, which leads to a higher oxygen content. To stimulate the microbial activity the biodegradable organic carbon compounds were supplemented. Molasses addition provides a high input of biodegradable organic carbon, which is necessary when BOD5 is low and the ammonium quantity is high.SludgeBiological treatmentPlantFilamentous structureBacteria belongings ZoogleaConference paper