THE EXCESS SLUDGE PRODUCTION DURING THE WASTEWATER TREATMENT. SLUDGE REDUCTION BY BIOLOGICAL PROCESSES

This PhD project focused mainly the OSA technology, developed at Trieste University but also consider the AnMBR technology that was developed at the Barcelona University,working with a laboratory scale AnMBR, fed with winery synthetic wastewater at low temperatures as novelty (from the start-up at 35°C, later at 25°C and finally at 15°C),and evaluating its removal efficiency and methanogenic activity. The COD removal was of 80% and 71% at 25°and 15°C, respectively and without suspended solids in the effluent.The main study on OSA technology was performed at the Trieste University, in teamwork with a wastewater treatment company (CAFC Spa, Udine). The novelty of this research is the use of a real wastewater feed in an OSA pilot plant.The research concerned a first period (1st and 2nd year) with the project and construction of an automated OSA pilot plant, located close to the CAFC wastewater treatment plant (12,000 PE) of Terenzano, a village about 70 km from Trieste, and fed with the same wastewater of the real plant. In the last part of the study (3rd year), the OSA pilot plant was studied (and modelled), by applying respirometric techniques, evaluating the quality of the effluent, the sludge reduction feasibility and the effect on biomass activity.