Since the catalyst cools during the cracking process, it must be removed cyclically and brought back up to the required temperature of about 700 °C. In addition, coke forms during the cracking reactions and settles on the catalyst surface quickly deactivating it. The catalyst thus needs to be regenerated. For this it is brought into contact with blown-in air in the regenerator at temperatures of 600 - 700 °C where the adherent coke is burned off.
Using oxygen-enriched air for this process can increase the efficiency of the coke burn off and thus increase the capacity of the regenerator. The use of oxygen in the regenerator has the following advantages compared to pure air operation:
- Possibility to increase capacity
- Processing of cheaper crude oil qualities
- Greater flexibility in operation