Coking gas is a by-product that comes from the coking ovens at a temperature of 900 °C. Crude tar and water are condensed out of this gas when it is cooled to around 20°C. Finally water and solids are all but removed from the crude tar.

Crude tar is further processed in tar distillation. Alongside pitch, which makes up approximately 50% of the coal tar oil, anthracene oil, naphthalene oil and scrubbing oil are also derived from it. Pitches, naphthalene, anthracene and various oils are produced in a final step.