A method of decoking a cracking furnace

A method of decoking a cracking furnace, the cracking furnace comprising at least one tube for transferring a feed, the at least one tube entering the cracking furnace at an inlet point and exiting the cracking furnace at an outlet point, the method comprising:

• heating the cracking furnace to a specified average temperature;
• injecting a gas mixture comprising air and steam through the at least one tube at a first air to steam ratio, thereby increasing an outlet point temperature to a first temperature and combusting at least a first portion of a coke on an internal surface of the at least one tube;
• injecting the gas mixture through the at least one tube at a second air to steam ratio upon observing a decrease in the outlet point temperature from the first temperature, thereby increasing the outlet point temperature to a second temperature and combusting at least a second portion of the coke on the internal surface of the at least one tube, and wherein
• the outlet point temperature does not exceed the specified average temperature;
• and
• the second air to steam ratio is greater than the first air to steam ratio.