Seeking help regarding the relationship between the carbon bed and post-combustion burning

1. The main reason for secondary combustion is that CO does not burn completely in the dense phase and rises to burn in the dilute phase. ⑴The low dense-phase temperature in the regenerator leads to incomplete combustion, resulting in an increase in CO concentration ； ⑵Insufficient addition of CO combustion aid ； ⑶The regenerative dense phase reserve is too low ； ⑷Insufficient main air volume or uneven distribution of main air into the regenerator ； ⑸Fluidization is abnormal ； ⑹The fresh dose was replenished too quickly. 2. The root cause of carbon accumulation lies in the loss of balance between coking and de-coking; the amount of carbon formed through de-coking exceeds that formed through coking, resulting in an increasing carbon content in the regenerant, like a snowball effect. ⑴The heavy oil blending ratio and the amount of slurry recycled are too high, resulting in significantly heavier feed materials; or the feed volume is excessive, and the atomization effect of the nozzles is poor, leading to an excessive amount of raw coke formation ； ⑵The main air flow is insufficient, failing to provide enough oxygen for burning ； ⑶Too low a reaction temperature or poor stripping efficiency in the settler results in the catalyst slurry containing oil ； ⑷The regeneration temperature is too low, resulting in poor charring effect ；