What is petroleum coke, and how is it produced?

Petroleum coke is a solid carbon material that is yielded from the coking process in oil refining. It is specifically produced during the thermal cracking of heavy crude oil when lighter fractions are separated and vaporized, leaving behind the denser carbon-rich residues. This process typically occurs in delayed coking units or fluid coking units, where heavy feedstocks undergo high temperatures and pressure to break down, allowing for the production of lighter hydrocarbons such as gasoline and diesel, while the carbon is left in the form of petroleum coke.

The production of petroleum coke is integral to the refining process, particularly for heavier crude oils that cannot be processed through standard distillation methods alone. This byproduct can be used in various applications, including as a fuel source in power generation and a key ingredient in the production of aluminum, steel, and other industrial materials. The emphasis on it being a byproduct highlights the fact that while petroleum coke is not the primary purpose of refining crude oil, it is an inevitable outcome of the processes used to maximize the yield of more valuable hydrocarbon products.