MMW and MSW Treatment Plant Poggiardo
Sudgas SrlPoggiardo | Lecce - Italy
- System description: Shredding, sorting and baling
- Waste processed: Mixed municipal solid waste and recyclables
- Plant capacity: 30 t/hour
The plant treats, in different shifts, either mixed municipal waste or dry waste from source separation.
The three following fractions are obtained from mixed municipal waste:
• Small size material;
• Large size material;
• Ferrous metals.
The small size material is suitable to go through a biological stabilization process, i.e. composting. In fact, this fraction of municipal waste contains organic components that may be composted. Furthermore, after treatment in the sorting plant, it is more homogeneous and uniform in size. The production of compost is a
technology that may reduce significantly the environmental impact deriving from organic waste disposal in a sanitary landfill.
The larger size fraction contains combustible mate-rials, such as paper, plastics and wood. It is thus suitable for the production of RDF (refuse derived fuel) to be used for generating heat or electricity.
In any case, this material can be disposed of in a landfill with a lower environmental impact, if compared to the disposal of untreated municipal waste. In fact, this mate-rial contains less organic matter and therefore it generates less biogas and leachate. Besides, shredding the bulky components and compacting material in bales occupies less landfill space. Ferrous metals recovered at the plant can be recycled for the production of steel by electric arc furnace, after refining if this is required by the steel scrap specifications. A slow speed shredder opens the bags containing waste and reduces the size of the bulkiest components. Both this shredder and the baler were supplied by third parties, while their installation in the plant was coordinated by Ecomaster. A conveyor belt lifts the shredded material up to the inlet chute of a rotary screen. This conveyor has a magnet to separate magnetic metals. Small size materials go through the screen and form the undersize fraction, which is collected by a conveyor set up under the screen. This fraction is then unloaded into roll-off containers by means of a swiveling conveyor equipped with ultrasound level meters.
A second magnet is set up before the station of the roll-off containers and separates further metals from the undersize fraction. The material that did not go through the screen is collected at the outlet of the screen drum and sent to the baler. The dry waste coming from source separation contains recyclable materials, such as paper, cardboard, plastic bottles and metals that are sorted to be recycled. A by-pass feeder prevents the shredder from processing this waste stream.
After screening the small size materials and separating magnetic metals, the material is sent to the sorting room. The materials recovered are dropped into bunkers located under the sorting room. The baler can process, in turn, materials from the storage bunkers, handled by wheel loader, or residual material from the sorting conveyor. Moreover, the baler can process directly recyclable materials which do not require sorting.