Nowadays, sludge dewatering is one of the greatest operational cost to wastewater treatment cycle.Specifically, 1t of fresh sludge to be disposed is composed, on average, by 0.25 - 0.30t of suspendedsolids, with an average cost for treatment and disposal around 280 - 470 €/t of suspended solids.Despite several technologies have been developed with the focus to reduce also the specific sludgeproduction, still mechanical dewatering represents a crucial step to limit the amount of sludge to bedisposed. Many physical–chemical parameters influence the sludge dewaterability: floc structure,particle size, bound water content, surface charge and hydrophobicity, Extracellular PolymericSubstances content and sludge retention time. Many authors agree in identifying the sludge originas one of the main aspect involved in sludge dewaterability. In order to elucidate the key factorsinfluencing the dewaterability process, the present work is aimed to investigate the influence of thetreatment plant lay-out on sludge dewaterability. The sludge samples were analyzed according toEN International Standards. The analyzed sludge samples were derived from 4 conventionalactivated sludge and 2 membrane bioreactor wastewater treatment plants (WWTPs). The resultsconfirm the complexity of the inter-relationships between many factors affecting the sludgedewaterability (i.e., WWTP lay-out, physical-chemicals and biological factors).
|Number of pages||11|
|Publication status||Published - 2015|