Glass Melting Technology: A Technical and Economic ... - OSTI

continues to operate using technology based on conventional furnace designs that were
developed over almost a century and a half ago.
Mature industry
Glassmaking is America’s oldest manufacturing industry, begun in the colonial forests near
Jamestown, Virginia, in 1608. Therefore, in economic terms, the glass industry is considered a
mature industry, yet it lacks the expected degree of standardization and common interests that
characterize a mature industry. Price and cost pressures are characteristic of high-volume,
commodity sales within the glass industry; however, it does not have standardized technology
and manufacturing operations. Mature industries are unwilling to make significant changes to
their principle manufacturing processes, due to the high investments involved. The existing
glassmaking technologies have generally evolved over an extended period of time among a small
community of practitioners with little tolerance for risk.
Industry segmentation
Given the segmentation of the glass industry, US glassmakers are challenged by very different
markets and products and do not share common concerns for operations and production. As a
whole, the industry is weakened by this fragmentation, which hampers collaboration that would
empower the industry as a whole with economies of scale. Each segment, and even individual
companies within a segment, usually operates with several different furnace designs and with a
variety of melting technologies, weakening its collective position.
Even though the common public perception of glass is that of a single material with a common
chemical composition, this is not true. The unique product requirements of each segment require
technology specific to the glass chemistries that define the physical properties of their products
and applications. Different melting technologies are sometimes used within each segment. Raw
materials differ from segment to segment, as do requirements for product quality and metrics for
quality measurement. To be compatible with the most productive fabrication processes of their
particular glass products, manufacturers require other properties, usually temperature versus
viscosity and coefficient of thermal expansion but can include a number of very different
parameters. Furnaces differ in size and employ different melting technologies, therefore,
requiring different capital and varying operating costs.
Although the segments vary in the technology used and in the products they manufacture, the
basic melting process is generally the same. All glass manufacturers employ melting technology
that involves high-temperature fluxing of silica sand with a variety of industrial minerals to
produce a particular glass composition. The industry segments share common concerns:
purchase of batch materials, purchase of energy, and melting of batch and cullet. In addition,
they share an ongoing need for capital to rebuild furnaces and maintain operations. Table II.1
defines glass industry segment by end-use markets.
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