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Sustainability of Municipal Solid Waste Management

FIGURE 5.5 Conveyor belts 155

using the new hierarchy of “cradle-to-cradle” discussed in Chapter 1. This
system will utilize the non-renewable resources, eliminate the problems
caused by MSW, decrease the cost of MSW management, and approach the
cradle-to-cradle concept without any use of incineration or landfill.

5.2 Transfer Stations

Transfer stations are used for very crowded communities, such as those with
narrow streets, as well as remote communities, for example rural commu-
nities with low quantity of waste. The transfer station is always recommended
to transport waste directly from the collection points to the recycling cen-
ter, which is usually situated some distance away from the generation point.
Transfer stations, which can be strategically located to accept waste from
collection trucks, can represent a suitable and more economic solution
(El-Haggar, 2004c).
The transfer station can be divided into several workstations. The first
workstation would include a conveyor belt as shown in Figure 5.5 where
trucks are allowed to enter leaving all the waste to be sorted manually on
the conveyor. A second workstation would include a glass crusher as shown
in Figure 5.6, where glass is crushed into small pieces – “cullets” – ready for
recycling. The third workstation would include a hydraulic press as shown
in Figure 5.7 to compact the sorted solid waste such as plastics, metals,
paper, textiles, etc. The hydraulic press is used to decrease their volume for
easy storage, handling, and transport to other companies for recycling.