Catalytic cracking scorch temperature
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In the catalytic cracking of the second stage of coking, what should be the minimum control of the coking temperature? Below what level does carbon heap occur?
Generally, the two-stage regeneration process involves repeated oxygen-depleted regeneration, and the temperature is controlled at 640---670°C. If it is too high, it will be detrimental to the catalyst, and if it is too low, it will not achieve the appropriate charring ratio and increase the secondary charring load. The minimum temperature also depends on factors such as the nature of the raw material, the processing volume, the heat taken by the heat exchanger, the carbon content of the semi-regenerated catalyst, etc., and it needs to be determined according to the specific situation.
Since it mainly burns hydrogen, the speed is fast and the time is short, so the temperature can be controlled at 650 degrees. The second cycle mainly burns, so under normal circumstances, the carbon content of the catalyst is not affected by the first cycle.
The distribution of the two main winds depends on the specific conditions of each device. As long as the regeneration quality is ensured
Generally, the charring temperature is controlled at around 650. Too high or too low is not good. Just make sure the catalyst passes regular testing.
The repeated temperature of the two-stage regeneration device is generally as follows:: Dilute phase temperature 660-670℃, dense phase temperature 670-680℃ ； The secondary temperature is generally as follows: Dilute phase temperature 690-700℃, dense phase temperature 680-690℃ ； As long as the temperature difference between the first and second phases of the dense phase is controlled as above, the carbon pile phenomenon will generally not occur. This post was last edited by xdx on 2009-2-24 13:00 ]
The temperature should not be too high. It is not good to exceed 700 degrees. As long as the carbon setting of the catalyst is qualified, it will be fine.
It's so easy for carbon to pile up there. Different oils and different processing volumes. The primary burning temperature of our device (smokeless machine) is between 640-680, the secondary dense phase is generally 630-700, the burning tank temperature is generally 630-660, and the dilute phase does not exceed 730. Sampling is taken and visually inspected in each shift, and carbon determination is made every two or three days. Carbon piles have only occurred twice in the 10 years since our installation, both caused by incorrect handling. (One time was a night shift, the external heater leaked, the bed temperature was low, and the processing capacity and oil refining were continuously increased. The other time was caused by water leakage from the old main fan)