The new series of high volume tanks emerged from the longstanding experience of Costarelli in the design and construction of washing plants. The special challenge of post consumer plastic waste required new technologies, with special consideration of the high content of the sinking content of the material and its subsequent processing to ensure a high degree of recuperation of plastic material. The design of the tank separates the floating material and the sinking material in one single tank, which simplifies the concept of the whole plant.
The tank pre-washes the shredded material (about 5 x 5 cm) and separates via float/sink method the floating fraction (Polyolefin's) from the plastic material with specific weight > 1 (PS, PET, PVC etc.) and of a large part of the paper and carton. For a thorough washing effect (complete elimination of paper EPS) the Centrifuges, i.e.. a Turbo-Wash upstream and a Dynamic-Centrifuge downstream is recommended.
The water circulates in closed loop and ist treated in a water treatment plant.
New line of modular tanks with 1 m standard segments, "goose neck" discharge for sinking faction and forced feeding with submerged augers for material
Effectiveness of Float-Sink Method
The following table shows the high effectiveness of the method. The results were obtained by an independent institution in a plant for mixed plastics, which is an extremely difficult material.