Reprocessing of domestically produced diesel in hydrocracking units
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I would like to ask my colleagues whether there are any methods of using a hydrocracking unit to reprocess the jet fuel and diesel produced by this facility itself, in order to increase the yield of heavy naphtha
Reprocessing? The jet fuel and diesel produced by the cracking unit are fed back into the unit again; is the target product naphtha? Processing it this way is not economical. If you want to increase the naphtha yield, why not increase the cracking depth during a single processing cycle? More cracking of naphtha will increase the yield.
To increase the naphtha yield here, it is generally sufficient to increase the degree of cracking. If the client wants to carry out reprocessing, should we consider low hydrogen consumption, or long-term operation of the refining catalyst?
What is your naphtha yield?
Reprocessing is not as effective as optimizing the catalyst grading; of course, the load on the distillation tower also needs to be taken into account.
The feedstocks include paraffin oil and reprocessed diesel; there are very few components in jet fuel that can be cracked, so basically no significant changes occur. For feedstocks that are diesel, reprocessed diesel follows the normal full reprocessing process.
Firstly, reprocessing consumes a portion of the raw material, which may increase the overall naphtha yield, but the amount of product remains largely unchanged. Secondly, this can be adjusted by increasing the reaction temperature and catalyst grading, so there is no need to take such actions. Finally, even in the case of reprocessing, should the feed location be considered, with hot feed being supplied to the high-temperature area in the middle section?
If it is not a two-pass hydrogenation process (where the tail oil passes through the reactor again), it is not recommended to do this, as the cost of hydrogen consumption needs to be taken into account.
Reprocessing domestically produced diesel is pointless; it’s a waste of resources