Petroleum coke, ‘pet-coke’, is a by-product of the coker process in the oil industry. In its raw form it is also called “green coke” or green petroleum coke (GPC). Calcined petroleum coke (CPC) is an important industrial commodity that links the oil and the metallurgical industries as it provides a source of carbon for various metallurgical applications [Boateng, 2016]. In the aluminum industry CPC is required for the manufacture of anodes for the aluminum potlines and in the steel industry it is used to manufacture carbon and graphite electrodes. Rotary kiln calcination is carried at high temperatures to remove volatile combustion matter of green coke (6 – 20 wt%) and densify the product for use as anodes. The process uses its own energy to fuel itself and can be energy self-sufficient.
Afterburners also known as pyroscrubbers are needed to scrub the off gases. This may be an added cost when retrofitting LWA kilns for pet-coke calcination but these afterburners are used to generate electric power. See kiln sizes in Table A.5.