36 / 66
34 Coal
obtaining metals from ore rocks using heat and chemical reduction. In a blast
furnace, coke is mixed with iron
ore
, such as hematite, and limestone, and heated to
temperatures of 3,000°F (1,650°C). The coke burns in air to make carbon monoxide
gas, and this takes away the oxygen from hematite to leave a form of iron called pig
iron, which is the basis of steelmaking and other iron industries. Coke is also a fuel in
smelting plants for copper, silver, and other metals.
The anthracite industry in North America is far smaller than the bituminous coal
industry, and almost all the anthracite comes from Pennsylvania. Its main uses are in
smelting metal ores; as an efficient, almost smokeless fuel for heating; in the electrical
industry; and for water filters.
Close view of a blast furnace used in making iron.