(best examples and good practices) on household organic waste ...

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Automated sorting has lower labour costs when compared to manual sorting.
Automation also assures the health of the employees that work to such kind of
facilities. Furthermore, the processing machines can be adjusted by adding new
sensors so that they can process different kind of materials, <strong>and</strong> can
consequently take more from the waste stream as new markets develop.
(Dubanowitz., 2000)
However nowadays it is not yet feasible to have automated waste separation
facilities because the presence of man still remains the most important factor
for the effective separation of the waste materials. Many mistakes can occur
during the automated separation process while these machines often need
external help for the separation of different kind of materials. (Dubanowitz.,
2000)
4.6 Material recovery process
Mechanical separation is a process which is comprised by many parts such as
size reduction, screening, air classification, magnetic separation, <strong>and</strong> nonferrous
(e.g., aluminium) separation. The most important parts of a MBT
facility are shown at the table below (Table 5.).(Tchobanoglous <strong>and</strong> Kreith,
2002)
‣ Size Reduction
‣ Air Classification
‣ Screening
‣ Magnetic Separation
‣ Glass Separation
‣ Non-Ferrous separation
‣ Densification
‣ Conveyors
(Table 5.): Mechanical unit processes used in waste processing facilities
(Tchobanoglous <strong>and</strong> Kreith, 2002)
As soon as the waste stream arrives in the facilities, it is dropped on to the
tipping floor. The unloading of the materials from the collection vehicles onto
the tipping floor must be efficient to protect the materials to be seperated.The
tipping floor must be constructed from proper materials. The Tipping floors use
frontend loaders to move the mixed waste onto conveyors that rise up to the
separation systems. This approach characterizes the tipping floor as one of the
most inefficient components of the material recovery facility since dropping
<strong>and</strong> moving the materials on the floor requires additional equipment <strong>and</strong>
causes large amounts of glass breakage <strong>and</strong> facility contamination. Because of