A coke oven is a device used to produce coke, a product that is derived from coal. The mixing and heating of bituminous coal at temperatures ranging from around 1832° to 3632°F (1000° to 2,000°C) within the airless oven yields the coke byproduct. This device is a crucial part of the coke-making process.
Coke is a solid remainder of combusted carbonaceous material, and it contains a minor quantity of ash and sulfur. It can be used as a fuel or as a reducing agent in blast furnaces used for the smelting of iron ore. Coke is generally considered to be one of the three fundamental materials for producing iron, which is then used to make steel, usually in combination with limestone and iron ore. The gasses from the oven may also be used as a fuel.
Most coke ovens produce this material by heating coal under controlled circumstances. As the absence of oxygen is important to yielding the best quality coke, the ovens are designed to be airless. They may also be arranged in batteries and strategically situated between heating walls. This can increase coke production and the efficiency of the oven.
In the coke-making process, treated coal is placed in the coke oven. Due to the high temperature inside, coal gas, coal water, and tar are separated from the coal. The gas and water then fuse together with carbon and the remainders of ash. The hard residue that remains at the end of this process is commonly referred to as coke.
The coal used for selection in the coke-making process is often an important part of the procedure. It may be selected according to factors such as ash and sulfur content, tar, plasticity, and volatility. The volatility of coal can be important, since it will allow for a greater quantity and higher quality of coke to be produced. This is because the more volatile the coal is, the more byproducts it will yield, but too much volatility can be a negative, as the byproducts become too porous for making quality coke.
Emissions of coke ovens have been shown by some studies to be dangerous to humans; this has led to the emissions being identified as human carcinogens. These studies have shown a correlation between the exposure of workers to the ovens and instances of types of cancer, including those that affect the lungs and intestines. Tests done on the skin of animals, like mice, also have demonstrated that exposure may produce malignant tumors.