High-Temperature Processes for the Production of Metals and Glass

Abstract

The production of metals has long been associated with high temperatures. Man moved beyond the use of naturally occurring materials, such as wood and stone, in approximately 6000 B.C. It is probable that the discovery that subjecting certain rocks to high temperatures resulted in metals was made accidentally in a cooking fire or, more likely, a potter’s kiln. Since that time the major part of our metal production has been carried out in processes that employ temperatures in the range of 300 to 1600°C. This technology, known as pyrometallurgy, is treated first in this chapter. Alternative or complementary technologies — hydrometallurgy (employing aqueous solutions and comparatively low temperatures, say, less than 200°C) and electrometallurgy (exploiting direct current to bring about electrochemical reactions) — are treated in Chapter 9. At the end of the present chapter we include a brief treatment of the production of glass. Glass production bears a resemblance to pyrometallurgical operations in that high-temperature liquids are handled and ultimately cast into solid form.