Is the catalytic reprocessing of diesel feasible?

I’ve never heard of reprocessed diesel. Reprocessed gasoline is used to increase the yield of LPG and propylene as well as to reduce the amount of olefins in gasoline, while reprocessed diesel is intended to increase the yield of gasoline? LPG yield?

Reprocessing of black diesel http://bbs.hcbbs.com/viewthread.php?tid=341513&highlight=%B2%F1%D3%CD%BB%D8%C1%B6 Reprocessing of substandard diesel http://bbs.hcbbs.com/viewthread.php?tid=328014&highlight=%B2%F1%D3%CD%BB%D8%C1%B6

Our catalyzed diesel is ready to be fed into the catalytic riser as a terminator to increase gasoline yield. It remains to be seen what the effect will be.

According to the sequential reaction steps of catalytic cracking, diesel is an intermediate product in this process; it is possible to recycle it. However, as a result of recycling, part of the diesel is converted into gasoline, dry gas, and coke, while diesel is also produced again. This new diesel has a higher density and a lower cetane number. Although the amount of diesel decreases, its quality improves less, and this factor needs to be taken into consideration overall. Qiwangda Company in Shandong uses the diesel reprocessing process, with aromatic compounds as the target product. I hope a friend of Qi Wangda can give a detailed introduction.

I also believe that reprocessing qualified diesel is not cost-effective from a profitability perspective, but increasing gasoline production is a political task that must be carried out.

It is technically possible to reprocess catalytic diesel or straight-run diesel; the considerations include, first, the limitations of the equipment such as the capacity of the steam compressor, and second, the economic viability. Given the current situation of a severe surplus of diesel and a shortage of gasoline, the economic efficiency of reprocessing diesel improves, so it is necessary to do a thorough cost analysis. Using diesel as a terminator in the Shuichanglong factory is a good idea: it helps to reduce diesel production, prevents secondary reactions, and avoids excessive cracking of diesel, which could lead to a sharp increase in steam generation. Its operating condition should be monitored.

Everyone can add an additional process for accelerating combustion in front of the terminator nozzle. Use unqualified, discolored catalytic cracking oil as a substitute for straight-run gasoline or crude gasoline to serve as a terminator. . . There is no technical problem with this. . . :lol

Before catalytic processing of the oil, hydrodearomatization must be carried out to increase the hydrogen content; otherwise, the quality of the diesel will continue to decline. Currently, there is a price difference of 1,000 yuan between diesel and gasoline. It offers no disadvantages in terms of technology or economic benefits. Going straight into catalysis is a bad idea.

It is recommended not to recycle it, as the loss is high and it is not cost-effective

When diesel prices are too low and gasoline prices are high, it is advisable to consider going to FCC or HC; either option is feasible

In my opinion, the issues related to catalytic diesel include the following: first, it needs to be sold as soon as possible, since many small factories do not have hydrogenation facilities. Second, if reprocessing is necessary, it can be done at atmospheric pressure. Mixing occurs at the raw material feed point, resulting in approximately 5% loss; if catalytic reprocessing is used, it is not recommended to use a terminator, as there is a large amount of raw coke produced. A medium distillation range can be utilized, as the main purpose of reprocessing is to change the color of the diesel.

What the original poster means is to convert diesel into gasoline as much as possible; therefore, feeding it into a fractional distillation tower will not achieve this goal. As for diesel going into catalytic reprocessing, straight-run diesel is certainly a viable option, but it is not cost-effective, as it means that diesel components of better quality are converted into catalytic diesel of lower quality; meanwhile, coke is produced alongside gasoline ； Secondly, catalytic diesel reprocessing is technically feasible, but its economic viability needs to be carefully evaluated; researchers at the China Institute of Petroleum Science have conducted studies on this topic, and the conversion rate is below 50%. If possible, catalytic hydrocracking of diesel can be considered; this allows for an increase in conversion rates while also maintaining the quality of the diesel, provided that care is taken to ensure that levels of basic nitrogen do not exceed acceptable limits.