A ROBUST BIOLOGICAL SYSTEM FOR SEWAGE TREATMENT IN TOURIST AREAS

This study was aimed at evaluating the effectiveness of an innovative compact biological system for treating at pilot scale municipal sewage produced in tourist areas characterised by intense seasonal water demand and wastewater discharge. The results obtained after a long term operation have shown that the proposed system was able to assure average removal efficiencies higher than 90% for COD (chemical oxygen demand), total suspended solids and TKN (total Kjeldahl nitrogen) independently of the influent concentration values and organic loading which ranged from 0.2 to 5.1 kgCOD/m3?d. Furthermore, the system was characterized by an excess sludge production 80% lower than that of conventional biological systems operating without a primary clarifier; an acceptable level of stabilization of excess sludge was also obtained indicating that a further stabilization process might no longer be required.