What is the material crossover temperature of the cracking furnace?

The material crossing temperature of the cracking furnace is the temperature at which the raw material enters the radiant section after being preheated in the convection section of the cracking furnace. The standard is based on 5-10% of the raw material starting to undergo cracking reaction. Different raw materials have different crossover temperatures, ethane is 679.5°C, NAP is 593°C, and AGO is 538°C. The length of the furnace tube in the radiant section is fixed. If the cross-section temperature is too high and the cracking reaction occurs too much in the cross-section, the primary products of the cracking reaction, ethylene and propylene, will undergo secondary reactions in the radiant section furnace tube, resulting in the loss of the target product. ； If the cross temperature is too low and the cracking reaction does not start in the cross section, the raw materials will leave the radiant section and enter the quenching boiler before fully reacting in the radiant section furnace tube, resulting in a reduction in product yield.

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