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

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glass breakage on the tipping floor, many facilities can only recover mixed
glass. (Dubanowitz., 2000)
The solution to such problems is to deposit materials directly onto a sunken
belt conveyor. The continuous movement of the discharged material by the
conveyors eliminates the need for the vehicles to pull forward when unloading,
lowering the facility’s area requirements. In addition, frontend loaders will not
be needed to constantly manipulate <strong>and</strong> route the materials on the floor, which
will reduce both congestion <strong>and</strong> the contamination from broken glass.
(Dubanowitz., 2000)
4.6.1.Materials Size Reduction
Size <strong>and</strong> volume reduction, is of great importance for various methods of
treatment <strong>and</strong> disposal of MSW as well as for cost-effective transportation of
recovered materials. Specifically the food waste need to be reduced in volume
in order to avoid further contamination of the environment <strong>and</strong> high
transportation cost. There is a wide range of size reduction methods available
<strong>and</strong> many types of size reduction equipment. Such equipment is employed to
reduce the particle size or increase the density of material in order to meet
market specifications or to reduce the cost of storage <strong>and</strong> transportation. Either
incoming MSW or separated <strong>and</strong> outgoing components can undergo size
reduction. Among the most common equipment used for size <strong>and</strong> volume
reduction of MSW are the Densifiers, Compactors, Baler, Shredders,
Hammermills (Vertical or Horizontal Shaft), Rotary Shear, Hammer Wear
,Dewatering Methods, etc.
4.6.2.Dewatering methods
Belt filter press
Belt filter press systems usually include a gravity drainage feeding section, <strong>and</strong>
a mechanically applied pressure belt arrangement. In gravity drainage, through
simple screens, a large portion of free water is removed. Pressure is then
applied at an increasing rate on the waste contained between supporting
porous belts (Demetrakakes., 1996). The dewatered waste cake is removed from
the belt with scrapers. In certain arrangements, a small vacuum must be
applied (4–6 kPa) to facilitate the removal of water accumulating at the surface
of the belts (Snyman et al., 2000). A prefl occulation step is often considered to
suit particular waste applications that are too liquid <strong>and</strong> to maximize
dewatering efficiency right from the start of the process during gravity
drainage. In roller press dewatering, the waste material is pressed between
rotating roller drums, where the single belt material only serves for conveying.
The bottom rollers are perforated to allow for drainage of the pressed liquid.