Via Tomba 25, Lugo (RA)
Physicochemical treatment plant for special liquid waste in Lugo (RA)
The plant, located at Via Tomba 25, Lugo (RA), is designed to treat special liquid industrial waste, including hazardous waste, produced by third parties and delivered in vehicles. Most of this waste is leachate from landfills and process waters from area businesses, which the plant is capable of purifying through traditional precipitation and clariflocculation treatment methods (D9).
The plant also receives slurry produced by composting plants of the group companies (D8).
Page updated 26 August 2015
After the acceptability check, the waste is stored in various reinforced concrete tanks and steel reservoirs of various sizes, depending on its specific characteristics. All the structures are equipped with the necessary safety apparatus, such as containment tanks and high-level detection filling pumps. The waste destined for treatment is properly equalised in three pre-storage tanks and then sent for the actual precipitation and clariflocculation treatment.
The process takes place in two mixers located in a shed. The pH is regulated in the first mixer so that it is neutral, with the addition of sulphuric acid and ferrous chloride (a flocculant). In the second mixer, milk of lime and anionic polyelectrolyte are added. In this way the metals are precipitated like hydroxides to guarantee the maximum capture of the metallic cations conveyed in the wastewater being treated. Later, the sewage sludge is transferred to the sedimentation tank. The overflow water from the sedimentation tank is transferred to two storage tanks with a capacity of 80 m≥ each and it is then transferred through a dedicated pipe for biological treatment at the Lugo consortium purification plant located in the same area. The sludge produced during treatment is extracted to undergo dehydration through filter-pressing, before disposal in an authorised landfill. The water resulting from the filter-pressing process is recirculated back to treatment. All storage and process tanks and reservoirs are kept in vacuum conditions by an aspiration system with the capacity of 12,000 m≥/hr, which conveys the gaseous flow to a treatment plant.