TRATTAMENTO DEPURATIVO DEGLI SCARICHI DI CONCERIA CON SISTEMA SBBR INTEGRATO CON L'OSSIDAZIONE CHIMICA

The paper reports the results of an investigation aimed at evaluating the laboratory scale performance of an innovative process for treating tannery wastewater coming from one of the larger Italian tannery district. In such a process biological degradation, carried out in a sequencing batch biofilm reactor (SBBR), was combined with chemical oxidation by ozone. The results were very satisfactory and high efficiencies were recorded for COD (96%) and nitrogen (98%) removal allowing treated effluent to meet the limits fixed by the Italian regulation in force without any additional polishing step. In addition, the process was characterized by low sludge production (lower than 0.1 kgSST kgCOD-1rimosso) and by high sludge density (about 98 gVSSl-1sludge) that permitted to obtain high biomass concentration in the filter (on average 20 gVSS l-1filtro).