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 post consumer wastes. The simplest form is a conveyor belt manned by laborers
who do the actual separation.
4.3.16.3 Separation of materials at final disposal sites generally
requires a large investment in equipment and a large, steady supply of raw
material to justify the equipment. Likewise, markets for the recovered
materials must exist. For these reasons, few military installations practice
disposal site separation. Techniques are mentioned here because some bases will
utilize them in some form and future trends may show more extensive use because
of increased costs for landfilling and incineration.
4.3.16.4 Recovery of Materials at Final Disposal Sites. This type of
recovery is distinguished from source separation in that recoverable materials
enter the waste stream and are mixed with nonrecoverable solid wastes. This
method will generally require the use of specialized equipment or machines not
normally found in the military supply system.
4.3.16.5 The overall success of a mechanized material recovery
facility depends on the technologies utilized. Ferrous metal recovery has been
proven effective at several locations, whereas aluminum recovery has achieved a
less successful track record. For economic and health reasons, mechanically
recovered paper is currently used almost exclusively for the production of
refuse-derived fuel (RDF) rather than fiber recovery. As a result, technologies
designed to recover fiber have received relatively less attention. Glass
recovery technologies have achieved limited success; more than aluminum, less
than ferrous metal.
4.3.16.6 The technology for separation of materials from military post
consumer solid waste is generally used in conjunction with energy recovery
systems. Several techniques are listed in Table 4-3-16A. The more common ones
are discussed below.
4.3.16.7 Hand picking of recyclables from conveyors prior to discharge
into transfer trailers or processing machinery is frequently practiced.
4.3.16.8 Magnetic separators usually consist of a belt, drum, or
pulley with a magnet used to attract and remove magnetic materials from refuse
or other materials (Figure 4-3-16A). At military industrial installations,
cranes with electromagnetic hooks (Figure 4-3-16B) can be used to separate
magnetic materials into large sorting bins.
4.3.16.9 Eddy current separators are used to separate aluminum and
other nonmagnetic metals using the properties of a magnetic field as a method of
sorting. An alternating current is passed through a piece of metal causing it
to become temporarily magnetic and thus deflected and separated.
4.3.16.l0 Heavy media separators use a suspension of finely ground,
dense minerals in water. When the mixture of glass, aluminum, and other
nonferrous metals is immersed in the liquid, the fluid density can be controlled
so that the aluminum and glass float while the other metals sink.
4.3.16.11
Equipment used in the paper industry can pulp waste paper
and separate foreign matter. Hot water and agitation are used for pulping
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