Carbon Black is produced by combusting oil or gas with a great deal of oxygen inside large furnaces. The furnace walls lined with bricks become very hot because the oxygen and oil combust. By varying the amount of oil and air, the internal temperature of the furnace can be altered, which permits manipulation of the particle size and particle connections of the carbon black being produced.
  The time required to produce carbon black from oil is so short that it cannot be confirmed by the human eye.

Classification of carbon black manufacturing processes