Delayed coking unit； What are the low and high blowing volumes? How to mix it? How to calculate it?
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Delayed coking unit； What are the low and high blowing rates for the coke tower? How to mix it? How to calculate it?
The purpose of supplying small amounts of steam in coking is to purge feed bypasses, to increase the light oil yield by stripping out coke oils, to stabilize the effects of tower replacement on distillation, and to maintain high temperatures in the coke tower during transition periods； The small steam supply volume must meet the requirements for purging and short-circuiting ； The purpose of supplying large amounts of steam is to cool the temperature of the coke tower during the coke transition process. It is generally required that the duration of this steam supply be sufficient to bring the temperature of the coke tower below 380 degrees, thereby preventing rapid cooling due to water injection from damaging the metal structure of the coke tower and protecting it from stress cracks as well as significant deformation caused by uneven heating
Customized according to the volatile matter and ash content of petroleum coke
In the fractional distillation tower accessed via the small blowdown route, the gas flow rate should be adjusted according to the gas velocity in the coke tower; it should not be too high, as this could cause the foam layer and coke particles to be forced into the fractional distillation tower, accelerating coking in the filter at the bottom of the tower； It should not be too small to prevent the feed from sticking to the oil and failing to be completely blown away, as this would result in less heat and oil gas being recovered.