Page 667 - Materials Chemistry, Second Edition

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638 Waste Management Practices: Municipal, Hazardous, and Industrial

TABLE 22.7
Practical Aspects of Electronics Deconstruction and Recycling

Metals Negligible amounts of metals such as copper, nickel and steel can be recovered from CRTs. Newer models
yield less precious metals than older ones. The copper wire yoke and the shadow masks are presumed
to be hazardous waste. At a minimum, recyclers of this material will be classified as generators by the
California DTSC
Plastics High-value engineering plastic resins such as high-impact polystyrene, acrylonitrile-butadiene styrene and
polycarbonates are sold to some domestic markets. Some companies have developed processes to recycle
these plastics. However, most plastics are exported to international markets

Glass CRT glass recyclers separate cullet into the following streams:
● Broken Color Dirty Mix, without metals — Dirty Broken Panels
● Broken Color Dirty Mix, with metals — Dirty Whole Panels
● Dirty Sorted Funnels — Whole CRTs
● Monochrome CRTs
“Mix” refers to panel and funnel glass combined; “dirty” refers to glass with coatings
Broken Color Dirty Mix, with metals is broken CRTs with the banding and masks. Broken Color Dirty Mix,
without metals is color CRTs that have metal banding, gun and mask removed. Rubber stoppers under the
yolk also need to be removed
Dirty sorted funnels and panels must be free of all metals except pins molded into the glass. Panel received
with frit is considered Broken Dirty Color Mix, without metals
Source: Reproduced with kind permission of the Materials for the Future Foundation, San Francisco, CA. 2001

FIGURE 22.8 Unit operations for CRT recycling. A compactor unit is linked with a HEPA baghouse to cap-
ture all dust and vapors.

and processing raw Pb from ore by supplying the metal, in the form of CRT glass, for CRT manu-
facturing. In California, CRTs destined for glass-to-glass recycling may be managed as Universal
Waste rather than hazardous waste (MFF, 2001).