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6 Recycling Solid Wastes

We are not to throw away those things which can benefit our neighbor. Goods are called good because
they can be used for good: they are instruments for good, in the hands of those who use them properly.

Clement of Alexandria (ca. 150–220)

6.1 INTRODUCTION
In an era when energy conservation, material cost and availability, and solid waste management are
major concerns to municipal administrations, scientists and the general public, it is imperative that
all parties appreciate the importance of recycling and of the value of products manufactured from
scrap. As we shall see, the benefits from waste recycling are not solely environmental, but economic
and aesthetic as well.
As discussed in Chapter 1, integrated waste management embraces a hierarchy of waste man-
agement options to achieve maximum economic and environmental returns. Recycling was listed
near the top of the hierarchy and will be addressed in this chapter.
As indicated in Chapter 2, recycling is not a new phenomenon. Animal manures, plant debris
and “night soil” have been applied to agricultural lands for millennia, and rag pickers were impor-
tant recyclers in America as recently as the early 20th century. Modern recycling can trace its roots
back to the 1960s, following the growing awareness of citizens to a myriad of environmental and
public health concerns. At that time, however, recycling programs often only involved the simple
segregation of materials from the waste stream. Unfortunately, markets were not established for the
purchase and reuse of separated materials. Manufacturers were reluctant to invest and participate in
new processing technologies and many were not yet equipped to handle these so-called “secondary
materials.” As a result, many separated materials found their way to the landfill. Many recycling
programs failed not only due to the lack of processing, then, but more importantly, due to the lack
of established markets for separated materials.
A new environmental awareness arose by the late 1980s, catalyzed by news of washups of med-
ical wastes, decline of landfill space, a possible global greenhouse effect, and atmospheric ozone
depletion. At this time it became apparent that sanitary landfills were rapidly closing and new ones
faced substantial regulatory and grassroot hurdles to permitting and siting. The cost of disposing
wastes correspondingly increased. As a result, interest in recycling by the public and, significantly,
also by industries and government increased markedly.
In recent years, numerous community recycling efforts have originated from efforts to reduce the
waste load to the local landfill, thus saving tax dollars. There are many examples of municipalities
establishing recycling drop-off centers or materials recovery facilities (MRFs) as a result of public
pressure. On a larger scale, however, a wide range of legislation at both national and state levels has
been promulgated that encourages the recycling of MSW. Many are aimed at waste generators,
whether the individual homeowner or business; some take the form of guidelines or requirements for
extending the lifetime of the local landfill. On the heels of federal mandates since 1990, most states
have set specific guidelines for reducing the tons of waste entering landfills. These quotas were to be
met via a combination of source reduction, recycling, and composting. Other legislation, in contrast,
addressed the purchase of recycled materials. Some government offices, for example, are now

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