Page 178 - Materials Chemistry, Second Edition

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Organic mixed Sustainability of Municipal Solid Waste Management 157
with rejects Collection

Composting plant Conveyor belt

Paper
Rejects Compost Metal Glass Plastics
Textile

Crushed Thin film Hard
Sand Press
glass plastics plastics

Bricks Compacted
Interlocks wastes
Wheels for recycling
Tables
Manholes
Road ramps

FIGURE 5.8 MSW 100% recycling system

from the waste and other treatment processes handle the remaining waste.
Recycling will reduce waste and the limited resources will be conserved for
future use since the scale of consumption of raw material is very large.
Recyclable materials are plastics, papers, metals, bones, glass, and food
wastes as well as unrecyclable wastes called “rejects”. Figure 5.8 illustrates the
system used to reach 100% recycling of non-hazardous MSW including recy-
cling of unrecyclable wastes as will be explained in detail through this chapter.
Recycling (material recovery) can provide a cost-effective waste man-
agement approach otherwise it will be a burden in our society at large. This
technique can help reduce costs for raw materials and waste disposal and
provide income from a salable waste as well as protect the environment.
The types of wastes that are separated and can be recycled easily with high
benefits include paper and cardboard, aluminum cans and tin cans, plastics,
textiles, bones, and glass. Organic waste or food waste recycling should be
treated with special attention because it contains some rejects such as con-
taminated plastic bags and small pieces of glass, for example, as a result of
unsorting of MSW at the source, which is the case in 60–70% of the world.
There are many ways to recycle organic waste and convert it into soil con-
ditioner (fertilizer) such as aerobic fermentation (composting), anaerobic