Category Glass and Energy
There are several types of melting furnaces used in the glass industry depending on the final product, raw materials, fuel choice, the size of operation, and economic factors. A melter can be either periodic or continuous. The latter is most widely used in large – scale operations. Continuous melters maintain a constant level by removing the glass melt as fast as raw material is added. Table II shows the three major types of furnaces and their advantages and disadvantages. The energy for melting comes from either the combustion of fossil fuels or electricity. The temperature necessary for melting ranges between 1300 and 1550°C. All furnaces are lined with high- temperature refractory materials to keep the corrosive melt from escaping and to insulate the melter.
Glass manufacturing is essentially a commodity industry, with the majority of product sold to other industries, such as beverage, construction, and automobile manufacturers. In 1999, the U. S. glass manufacturing industry produced more than 18 million metric tons, worth approximately $17.6 billion. In the European Union, 1996 production was approximately 29 million metric tons (Table I).
The overall goal of glass manufacturing is to convert crystalline raw materials into a homogeneous, flowing liquid that is free of visible defects that can be formed into a final product. This needs to be accomplished as quickly and as economically as possible and, at the same time, comply with all environmental regulations...Read More
Glasses can be found in the natural environment, mostly in areas of volcanism where erupted magma is quickly cooled before crystallization can occur. Perhaps the best known example is obsidian, a black glass that consists mainly of oxides of silicon, aluminum, calcium, and sodium and/or potassium.
Commercially produced glasses differ widely in chemical composition and in physical and optical properties. Various materials can form a glassy or vitreous structure, such as the oxides of silicon and boron. Most commercial glasses are based on silica (SiO2), which is the most abundant material on the earth’s crust and is an excellent glass former. There are some nonsilicate glasses, but they make up only a very small fraction of commercially produced glass.
Pure vitreous silica glass can be ma...Read More
CHRISTOPHER W. SINTON
Alfred, New York, United States
2. Types of Glass
3. Introduction to Commercial Glass Manufacturing
container glass The largest glass sector; formed by a two – stage process of initial forming by pressing followed by blowing to obtain the finished hollow shape. cullet Scrap or waste glass that is added to the batch materials.
float glass Flat glass that is made by floating molten glass on a pool of molten tin.
glass A material with a three-dimensional network of atoms that forms a solid lacking the long-range periodicity typical of crystalline materials. optical fibers Very high-purity silica glass fibers used to transmit light for telecommunications...Read More