Best Practices in Glass Recycling
Product Manufacturing / Container/Fiberglass
Page 1 of 2
Cullet Specifications for Container Manufacturing
Material: Recycled Glass
Issue: Container manufacturing is the primary market for recycled glass cullet in the United States.
Although all container manufacturers use some recycled cullet in glass batches, there is a lack of uniform
specifications for both recycled glass and furnace-ready cullet. This can represent a significant market
barrier to processors of recycled glass seeking to access the primary market. Often processors design
systems to meet the needs of specific manufacturers. This can leave processors vulnerable to changes in
the consumption patterns of a single manufacturer. Industry-wide quality requirements are needed to
ensure that suppliers have equal access to container manufacturing markets. Further, specifications
written at the corporate level are subject to interpretation at the plant level. Plant engineers may have
expectations of cullet that are more or less stringent than the written specifications. As a result, the
quality assurance procedures undertaken by those managers may tend to be more subjective than
Best Practice: The next page contains a specification derived from existing specifications and
interviews with processors and users. It may serve to educate those unfamiliar with cullet specifications and
as a starting point for development of uniform specifications.
Incipient trading in recycled glass on the Chicago Board of Trade (CBOT) may
help to open an industry-wide discussion for the establishment of uniform specifications. Whether or not
CBOT trading succeeds, that discussion should continue within the glass manufacturing industry.
Benefits: The existence of well-defined industry specifications can potentially be a benefit to both
processors and users of furnace-ready cullet. Processors can design their systems knowing that they are not
subject to the whims of a si