Mathematical model for describing the process in the regenerator of a catalytic cracking unit 43–102

Conclusions

Utilizing the mathematical model proposed, we have studied the effects which the initial coke content of the catalyst, the circulation rate, and the temperature at the regenerator top have on the regeneration in a 43–102 unit.

A rise of the initial coke content (at unaltered values of the other parameters) considerably accelerates the warming-up process of the catalyst in the regenerator and shifts the “hot spot” into the lower sections of the regenerator. The removal of coke by burning may be incomplete both at high and at too low values of the initial coke content.

Acceleration of the circulation rate (at unaltered values of the other parameter) has only a slight effect on the temperature of the “hot spot” in the regenerator. The “hot spot” is shifted in the direction of circulation of the current, and the regeneration does not attain the specified depth at high circulation rates.

The temperature at the regenerator top has a strong effect on the temperature profile. A lowering of the temperature at the regenerator top results in a drop of the temperature in the “hot spot” of the reactor and in incomplete burning of the coke.