There are several types of petroleum coke, which differ according to the method of processing and refining. Among the most important of these types:
Sponge Coke
It is a petroleum coke produced from heavy residue feedstocks by Pyrolysis in a fluidised bed. The reason why it is called a sponge is due to its high porosity and low bulk density.
Sponge coke is mainly used to produce electrodes for the aluminium industry. Sponge coke is ideal for anodes due to its high purity, low sulfur content, and good electrical conductivity. It is also highly resistant to thermal shock and has a low coefficient of thermal expansion.
Sponge coke is also used as fuel in industrial boilers and cement kilns. Its low sulfur content causes it to produce less sulfur dioxide emissions when burned.
Shot Coke
This type is produced during the delayed coking process. The coke particles are rapidly quenching, causing irregularities in their structures. Accordingly, it becomes difficult to handle and unacceptable for special Coke applications. For example, anode production requires high purity low porosity coke.
It can also be used as a fuel in various industrial processes, including cement kilns and power plants. Its high porosity makes it provide good combustion properties and reduces emissions.
Needle Coke
It is produced exclusively from fluid catalytic cracking (FCC) decant oil or coal tar pitch.
Its unique structure and high purity make it ideal for producing high-quality graphite electrodes, essential for manufacturing batteries for electric vehicles (EVs) and other energy storage systems.
