Coke Ovens (Waldo)
The volatile constituents of the coal—including water, coal-gas, and coal-tar—are driven off by baking in an airless oven at temperatures as high as 2,000 degrees Celsius. This fuses together the fixed carbon and residual ash. Most coke in modern facilities is produced in "by-product" coke ovens, and the resultant coke is used as the main fuel in iron-making blast furnaces. Today, the hydrocarbons are considered to be by-products of modern coke-making facilities (though they are usually captured and used to produce valuable products). Non by-product coke ovens, burn hydrocarbon off-gases on site to provide the heat needed to drive the carbonization process.
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