How is coke made? (Delayed coking)
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Delayed coking is a secondary petroleum processing technique that involves using hydrogen-poor heavy oils as raw materials to carry out deep thermal cracking and condensation reactions at high temperatures (around 500°C), in order to produce gas, gasoline, diesel, wax oil, and coke. The so-called delay refers to the process in which coking oil (feed oil and recycled oil) is heated rapidly to the coking reaction temperature using a heating furnace; no coking occurs inside the reaction tubes, and instead the oil goes to the coking tower where the coking reaction takes place. This delay effect is what gives rise to the term delayed coking technology. There is a fanciful hypothesis: after the feedstock is heated to the reaction temperature (about 500°C), it is cooled down within a short period of time to below the coking reaction temperature (420°C or lower). What will be the physical properties of the feedstock residue at this point? What I mean is: it’s not in a normal production state; instead, the raw materials are cooled down and then transferred into tanks (at, for example, 150 degrees). Just a hypothesis: lol. Last edited by Hongru on 2009-3-18 11:14.]
The crude oil is heated to 500°. The pipeline cokes up. . . .
If the crude oil is heated to 500°, the furnace tubes won’t coking, right? And if the temperature is reduced to below the temperature required for coking reaction in a short period of time, the pipes probably won’t coke either, right? :loveliness: Last edited by Hongru on 2009-3-17 20:58 in this post ]
For variable-temperature operation, the poster can take a look at the needle coke production process.
If the reaction temperature is too low, soft cokes and pitch cokes will form, making coke removal difficult.
Try to keep the temperature of the furnace tubes from being too high to avoid coking