UPGRADING OF A WASTEWATER TREATMENT PLANT SERVING A ROAD TUNNEL CONSTRUCTION SITE

Abstract

The construction of the Lioni-Grottaminarda road, in the province of Avellino, required the building of viaducts and tunnels, with the consequent production of drilling fluids and run-off water that require an appropriate treatment before discharge. A treatment plant was already in operation, but it was not able to achieve the law limits especially with high flow rate. The article describes the upgrading of the treatment plant serving the road construction site. The plant was started up in the initial configuration already able to deal with COD and TSS. However, the plant had a reduced treatment capacity with a maximum flow rate of 15 m³/h which required the constant presence of personnel. Instead, after the upgrading, the plant was able to continuously treat up to 50 m³/h and the complete automation of management and control was obtained. Furthermore, with the use of CO2 it was possible to obtain a further increase of the treatment efficiency. Finally, with the installation of a sand filter and an activated carob filter it was possible to further improve the removal of suspended solids and surfactants.