Who knows the role of the depentane tower in the reforming catalyst unit?

It’s just a distillation tower that serves to separate substances. Last edited in this post by brainandrain on 2009-4-19 09:44

Currently, the stabilizer towers of newly built continuous reforming units usually consist of two towers, de-C5 and de-C4.

During the reforming process, reactions such as aromatization, cracking, and isomerization take place under the action of a catalyst, resulting in the formation of lighter components (C9 fractions). At this point, it is necessary to separate out those components with molecular weights lower than C5 and those higher than C9, so that the C6–C8 fractions can be sent to the extraction unit for the production of triphenyl products.

The main objective is to remove the components with a carbon number of 5 or lower, so as to ensure that the octane rating and aromatic content of the reformed gasoline meet the required standards and satisfy the process requirements. Among the components below Carbon 5, Carbon 3 and Carbon 4 are liquefied gas components that cannot be used in gasoline engines. Component 5 of carbon is light oil, which can be used to produce blended gasoline, solvent oil, and industrial light oil.

Reformate oil generally needs to first pass through a stabilizer column to remove components below C4, and then through a pentane removal column to remove C5. Primary function: For companies that do not use aromatic hydrocarbons in their processes, pentane-free oil is generally used to produce high-octane gasoline; the removal of C5 compounds serves to increase the octane rating of gasoline and reduce its vapor pressure ； For companies with aromatic compounds processing facilities, C5 removal is aimed at reducing the non-aromatic components that enter the extraction units, improving the purity of aromatic compounds, and lowering the energy consumption of these facilities.

It mainly removes C5 to increase the octane rating of gasoline, and provides raw material for the aromatic extraction unit.

As the name implies, dewaxing is the removal of C5

The depentanizer and stabilizer of our reforming unit are the same tower. The tower used to produce raw materials for aromatic compounds is called a depentanizer, while the tower used to produce stable gasoline is called a stabilizer! ! !

I also have a question: could someone tell me about the composition of the top and bottom products from the depentanizer they operate?

Decarboxylation 5 is intended to reduce the non-aromatic components that enter the extraction unit, thereby increasing the purity of aromatics and preparing them for subsequent extraction processes

1. The depentane tower is used to remove components with molecular weights lower than C6; the gas in the top reflux tank consists mainly of C3/C4 and some CH4, while the liquid from the reflux tank is sent for use as C5, that is, pentane oil, for other purposes. 2. The heavy components at the bottom of the tower are used for blending before gasoline upgrading, but after the gasoline is upgraded, benzene needs to be removed; even if light components are not removed in the pentane removal tower, benzene must be extracted and removed. 3. It is best to remove it from the pentane stripping tower; otherwise, it will affect benzene extraction. 4. The above light components have a severe impact on the octane number of gasoline in the pentane removal tower; in particular, the octane number of gasoline in some cases is measured at the sample point at the bottom of this tower. Also, OP, I strongly suspect you’re from the same unit as me. Otherwise, why would you ask this question?

In my understanding, aromatic compounds above C6 and non-aromatic compounds cannot be separated using distillation towers because they form azeotropes; that is why complex extraction techniques are employed. The pentane component can be separated from the other components using simple distillation, eliminating the need for an extraction tower; this reduces costs and optimizes the process

Upstairs, did you understand what I said? May I ask, can a depentane tower separate benzene? The key point now is the improvement in gasoline quality, which imposes requirements on benzene. If not through benzene extraction, where then? In the stomach?

I learned it, but I don’t really understand it well

It mainly involves cutting out the components below carbon 5

Which company uses such an efficient extraction method to separate carbon-8? What brand is the solvent used? Please give some details