Page 199 - Materials Chemistry, Second Edition

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170 Waste Management Practices: Municipal, Hazardous, and Industrial
The primary reason for the increased interest in mechanized facilities for waste processing is that
as MSW disposal costs rise, a greater incentive develops in favor of recycling, and convenient and rapid
methods of separation and processing develop. For example, in areas where landfill tipping fees are
below $30 to 40 per ton, recycling the waste stream may not appear economically attractive to munic-
ipalities and the waste industry. However, with tipping fees in some areas exceeding $100 per ton, cities
and waste management companies clearly see the advantage to serious investment in recycling.
The two major configurations of MRFs are:

• Facilities which handle source-separated materials (“clean MRFs”)
• Facilities which handle mixed (commingled) wastes (“dirty MRFs”)

In many parts of the United States, markets exist for most materials recovered from the waste
stream. In those markets the specifications for separated materials will vary. Some of the forms and
conditions applicable to finished products are shown in Table 7.1.

TABLE 7.1
Some Forms and Conditions Applicable to Products to be Recycled

Paper
• Separated by grade (laser-quality white, mixed colored paper, old newspaper,
corrugated, etc.)
• Baled or loose
• Dry
• Clean (or not weathered)
Ferrous Containers
• Flattened, unflattened, shredded
• Labels removed
• Clean or limited food contamination
• May not include bi-metal
• Loose, baled, or densified into biscuit form
Aluminum Containers
• Flattened, shredded, baled, or densified into biscuit form
• Free of moisture, dirt, foil, plastic, glass, oil, other foreign substances
PETE and HDPE
• Baled, granulated
• Separated by color or mixed
• Without caps
Glass
• Separated by color or mixed
• Size of cullet specified
• Nature and amount of allowable contamination
General
Available markets for secondary materials typically specify the means of packaging and
shipping each product. The specifications depend upon location and end-use. The specifi-
cations often include the following:
• Skids or pallets
• Bundles, bins, boxes, cartons, or drums
• Trailer loads
• Roll-offs
• Rail cars
Source: U.S. EPA, EPA/6025/6-91/031, 1991.