Coke is a nearly pure carbon product made from coal that is critical in many industrial processes, steel-making in particular. It is made by carefully heating coal in an oxygen-poor environment to drive off volatiles, all while not igniting the carbon. Typically the coal is placed in an enclosed chamber, a so-called coke oven, to smolder for about a day. Then the finished coke is doused with cold water to stop any further combustion, at which point it can then be shipped to the ultimate market. These ovens were built…
