1. From coal: This is pressed solid carbon and flyash residue, resulting from the destructive distillation of bituminous coal, baked in the absence of oxygen in an oven to burn off volatile constituents and fuse the carbon and flyash together. About 90 percent carbon, its heating worth is nearly 25 million BTUs per ton. Burned primarily in iron ore smelting in blast furnaces. Typically, the ratio of about 550 kilograms, or roughly 1200 pounds, of coke is used per one ton of pig iron. This is about a 60% ratio. 2. From oil: The cracking of petroleum is the source of this pressed, solid residue . Five barrels of oil to roughly one ton, or about 900 kg. of coke, is the typical ratio. About 95 percent carbon, it has a heating worth of about 26.5 million BTUs per ton, and is consumed primarily as a refractory lining for arc furnaces and in the manufacture of synthesis gas and carbon electrodes.
