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 rather than chemicals. This process has been incorporated into certain resource
recovery systems to recover paper fibers from municipal solid waste.
4.3.16.12
Source separation is usually preferred over separation of
materials at the final disposal site because it is easier, less expensive,
requires limited equipment, and generally results in a higher grade of recovered
material. Disposal site separation does, however, yield concentrated recycle
streams and shows reduced transportation costs over source separation/collection
options.
4.3.16.13
Source Separation. DoD Directive 4165.60 (Dec 1986 Draft
version) "Solid, Hazardous and Petroleum Waste Management" requires the recovery
and recycling of solid and other waste materials to the maximum extent
practicable. Source separation is one of the simplest methods of compliance with
this requirement. Separation of other materials for which there is a market may
be accomplished and is encouraged. A source separation program may be instituted
at an installation only after the DRMO determines that markets exist for the
separated materials. If markets do not exist, source separation is not required.
The minimum requirements for source separation considerations are:
1.
High-grade office paper -- any installation employing over 100 office
workers.
2.
Newspapers -- installations with more than 500 family housing units.
3.
Corrugated containers (cardboard) -- installations where commercial
establishments collectively generate more than 10 tons per month.
4.3.17
Recovery of Energy
4.3.17.1 General. Energy recovery is now becoming a very popular
method for disposal of solid waste. The cost of disposal can vary substantially.
An economic study must be done at each installation to determine if waste to
energy is feasible. Sale of steam or electricity and tipping fees can provide
income for large installations. This income must offset operating costs
including maintenance. Maintenance costs are typically very high in large RDF
units. For small incinerators (more typical at military installations), waste
volume reduction is usually the primary goal. Here the cost of the incinerator
(operating and depreciation) must be offset by savings in other waste disposal
practices (e.g., landfill). (Some installations use incinerators to provide
supplementary building heat especially in winter months.) At military
installations, small incinerators are good candidates to supplement steam or hot
water heating requirements. Generation of electricity usually requires large
capacity furnaces such as those shown in Figures 4-3-17A and B to be economical.
Few military installations are large enough to support an incinerator that
produces primarily electricity. Table 4-3-17A lists processes for recovering
energy from solid wastes either as thermal energy or stored chemical energy.
4.3.17.2 Energy recovery by incineration typically takes one of
four different methods. The large-sized waterwall mass burning systems
(Figure 4-3-17A) are generally preferred in smaller cities. The prepared
fuels of RDF systems are favored where materials recovery is an important
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