EP2426189B1 - Method for producing kerosene and diesel fuels using light unsaturated cuts and BTX-rich aromatic cuts - Google Patents

Description

INTRODUCTION

The evolution of automotive engines is currently driving an increase in the demand for diesel fuel at the expense of that of gasoline.

Forecasts for the evolution of the automotive fuel market point to an almost universal decline in the world of gasoline demand.

Thus, while in 2000 the ratio of gas consumption to diesel was 2, it is expected that it will be close to 1.5 in 2015.

For the European Union, this reduction is extremely strong, since this ratio, which was 1 in 2000, should increase to 0.5 in 2012, and even drop further.

In addition, the demand for kerosene is also expected to increase significantly in the coming years in connection with the evolution of the air transport market.

This unavoidable evolution towards an increased demand for middle distillates, and the decrease in the demand for petrol, poses a serious problem for the refining industry in adapting supply to demand, and this in a very short time that is not very compatible with the construction of new installations that are costly and time consuming to implement, such as the hydrocrackings of vacuum gas oil.

The present invention provides an attractive solution allowing from light cracked naphtha (possibly including any proportion of C3 and C4 olefinic cuts called "LPG"), and an aromatic cut rich in BTX, to meet an increased demand for fuel diesel and kerosene, without involving new and expensive hydrocracking units.

The solution described in the present invention is particularly well suited to remodeling of existing refining units.

PRIOR ART

In a market dominated by the consumption of gasoline, as is the case for example in the United States, the production of diesel fuel is ensured essentially from the so-called "straight run" middle distillates, that is to say from direct distillation of crude oil.

These middle distillates must be hydrotreated to meet the now very strict specifications of sulfur content (10 ppm max) and aromatics contents. Currently, this production is notoriously insufficient and requires refiners in certain areas especially Europe, to import diesel fuel to meet domestic demand.

Conversely, and particularly in Europe, refiners face surpluses of gas whose exports in geographically deficient areas are uncertain in the short term because of the increase in refining capacity and / or the decrease in consumption in the regions. concerned areas.

For all these reasons, a number of refiners have built hydrocracking plants that convert heavy cuts such as vacuum gas oil into high quality diesel fuel. However, this process is very costly in investment and utilities because it operates at very high pressure (above 100 bars), and leads to a very high hydrogen consumption (of the order of 10 to 30 kg of hydrogen per tonne of hydrogen). load), requiring the implementation of a specific hydrogen production facility. Other less expensive solutions for producing diesel fuel are possible, namely the oligomerization of light olefins having from 3 to 6 carbon atoms, for example from catalytic cracking. However, these olefinic cuts very often contain sulphurous and nitrogen impurities which rapidly deactivate the oligomerization catalyst and can make the process less economical. It is therefore necessary to purify the charge of the oligomerization. This is done by adding purification equipment, usually in several stages, including various adsorbent masses, regenerative or non-regenerative.

The patent application US2010 / 108568 discloses a process for producing kerosene from C5 + naphtha and C2-C5 hydrocarbon gases derived from Fischer-Tropsch synthesis by oligomerization of the feed to form light hydrocarbons, kerosene and a distillate, hydrotreating kerosene, flavoring a C3 + cut from Fischer-Tropsch, alkylation of the aromatic rich naphtha fraction with the olefinic cut of the light hydrocarbons of the oligomerization step and the hydrotreatment of the kerosene product of the alkylation step.

The present solution can be defined as an alternative to the "hydrocracking" solution, using an oligomerization of light olefins of 3 to 10 carbon atoms, preferably of 4 to 6 carbon atoms, coupled to an alkylation of olefins. from 8 to 10 carbon atoms, not reacted to oligomerization on a high-BTX cut, generally available from a semi-regenerative or regenerative reforming.

This alkylation results in a cut in the range of middle distillates (gas oil or kerosene) which must then be hydrotreated and / or hydrogenated to produce commercial products.

The solution that is the subject of the present invention remains economically much less expensive than the hydrocracking solution in terms of investment, utilities and hydrogen consumption, and leads to a reduction in gasoline and an increase in distillate in the same order of magnitude.

SUMMARY DESCRIPTION OF THE INVENTION

• une étape optionnelle 1 d'hydrogénation sélective (SHU) de la coupe essence de départ,
• une étape 2 de traitement sur catalyseur acide (TR) de l'effluent issu de l'étape 1,
• une étape 3 de distillation de l'effluent de l'étape 2 réalisée dans une première colonne à distiller (CD1) permettant de séparer en tête une coupe oléfinique (4) ayant un point final d'ébullition d'environ 60°, intermédiairement une coupe (5) d'intervalle de distillation compris entre 60°C et 150°C, et en fond une coupe (6) de point d'ébullition supérieur à 150°C, qui est envoyée vers une unité d'hydrotraitement (HDT), l'effluent (12) de l'unité d'hydrotraitement étant envoyé vers une unité d'hydrogénation totale (HT) qui produit le gazole recherché (13),
• une étape 4 d'oligomérisation (OLG) de la coupe oléfinique (4) éventuellement en mélange avec une coupe LPG (10) contenant des oléfines, de laquelle on extrait après distillation un flux (7) d'oléfines oligomérisées à nombre d'atomes de carbone allant de 8 à 20, qui est envoyée pour une première partie par le flux 7a, vers l'unité d'hydrotraitement (HDT) constituant l'étape (6), et pour une seconde partie par le flux 7b, vers l'unité d'hydrogénation totale (HT),
• une étape 5 d'alkylation du flux (8) d'oléfines en C3 et en C8 sur la coupe BTX (9), l'effluent (11) de l'unité d'alkylation (ALK) étant envoyé dans une seconde colonne à distiller (CD2) de laquelle on extrait 3 coupes:
• une coupe essence (11a) de point d'ébullition inférieur à 100°C qui est envoyée vers le pool essence,
• une coupe intermédiaire (11b) d'intervalle de distillation compris entre 100°C et 150°C, essentiellement constituée des BTX n'ayant pas réagi, qui est en majorité recyclée à l'entrée de l'unité d'alkylation (ALK), à l'exception d'une fraction constituant la purge de ladite unité (ALK) qui est elle même envoyée au pool essence après stabilisation,
• une coupe lourde (11c) de point d'ébullition supérieur à 150°C qui est envoyée à l'unité d'hydrogénation totale (HT) de laquelle est extrait le gazole recherché (13).

The present invention describes a process for producing gas oil (13) from a gasoline cut (1) from a catalytic cracking unit, and a BTX cut (9) from a catalytic reforming unit of species, using the following sequence of steps:

• an optional step 1 of selective hydrogenation (SHU) of the starting gasoline cut,
• a step 2 of treatment on acid catalyst (TR) of the effluent from step 1,
• a step 3 of the distillation of the effluent of step 2 carried out in a first distillation column (CD1) allowing to separate at the head an olefinic cut (4) having a boiling point of about 60 °, intermediately a section (5) of distillation range between 60 ° C and 150 ° C, and bottom a section (6) of boiling point above 150 ° C, which is sent to a hydrotreating unit (HDT) the effluent (12) of the hydrotreating unit being sent to a total hydrogenation unit (HT) which produces the desired diesel (13),
• a step 4 of oligomerization (OLG) of the olefinic section (4) possibly mixed with an LPG (10) containing olefins, from which a stream (7) of oligomerized olefins with a number of atoms is extracted after distillation of carbon ranging from 8 to 20, which is sent for a first part by the flow 7a, to the hydrotreating unit (HDT) constituting the step (6), and for a second part by the flow 7b, to the total hydrogenation unit (HT),
• a step 5 of alkylation of the flow (8) of C3 and C8 olefins on the BTX cut (9), the effluent (11) of the alkylation unit (ALK) being sent in a second column to distiller (CD2) from which 3 cuts are extracted:
• a gasoline cut (11a) with a boiling point below 100 ° C which is sent to the gasoline pool,
• an intermediate cut (11b) of distillation range of between 100 ° C and 150 ° C, essentially consisting of unreacted BTX, which is mostly recycled at the inlet of the alkylation unit (ALK) , except for a fraction constituting the purge of said unit (ALK) which is itself sent to the gasoline pool after stabilization,
• a heavy cut (11c) of boiling point greater than 150 ° C which is sent to the total hydrogenation unit (HT) from which is extracted the desired diesel (13).

The petrol fraction constituting the charge (1) is a catalytic cracking gasoline which contains from 5 to 10 carbon atoms, and preferably from 5 to 7 carbon atoms.

According to a preferred variant of the process according to the present invention, step 2 of treatment with an acidic catalyst (TR) uses an acidic catalyst of ion exchange resin or phosphoric supported type, or any acid catalyst previously used in the steps downstream oligomerization (OLG) or alkylation (ALK), in a temperature range of 20 ° C to 350 ° C, preferably from 40 ° C to 250 ° C, and in a pressure range of 1 bar at 100 bar, preferably from 10 to 30 bar, and in a range of VVH from 0.1 hr -1 to 5 hr -1, preferably from 0.3 hr -1 to 2.0 hr -1.

It is recalled that 1 bar = 10 ⁵ Pascal and that the VVH designates the ratio between the volume flow rate of charge and the volume of catalyst.

In the process according to the present invention, the oligomerization step 4 is fed with the cracking gasoline (4) and optionally an LPG cut containing olefins, and operates on an acid catalyst preferably of zeolitic type, or silica alumina in a temperature range of 100 ° C to 350 ° C, and in a pressure range of 20 to 70 bar, and in a range of VHV of 0.2 hr-1 to 1.0 hr-1.

In the process according to the present invention, the alkylation step (ALK) is fed by the effluent (8) of the oligomerization unit (OLG), and by a rich aromatic cut (9) containing From 6 to 12 carbon atoms, and more preferably from 6 to 9 carbon atoms, and works on an acidic catalyst, preferably of zeolitic or silicoaluminate type, in a temperature range of 100 ° C. to 350 ° C., and a pressure range of 20 bar to 70 bar, and in a range of VVH from 0.1 hr-1 to 2.0 hr-1.

According to another preferred variant of the process according to the present invention, step 6 of hydrotreatment (HDT) uses a catalyst containing at least one metal chosen from Ni, Co, and Mo, and operates in a temperature range of 50 ° C to 400 ° C, preferably 100 ° C to 350 ° C, and in a pressure range of 1 bar to 100 bar, more preferably 20 to 100 ° C. bars at 70 bar, and in a range of VHV from 0.1 hr-1 to hr-1, and preferably from 0.5 hr-1 to 5.0 hr-1.

According to another variant of the process according to the present invention, step 6 of hydrotreatment (HDT) uses a catalyst containing at least one metal chosen from Pd and Pt, and operates in a temperature range of 50 ° C. to 300 ° C. ° C, and preferably from 100 ° C to 250 ° C, in a pressure range of 1 bar to 100 bar, and preferably from 20 bar to 70 bar, and in a range of VVH of 0.10h. 1 to 10 h -1, and preferably from 0.5 h -1 to 5.0 h -1.

Finally, according to a last variant of the process according to the present invention, step 2 of treatment on acid catalyst (TR) is preceded by a step 1 of selective hydrogenation (SHU) of the starting gasoline cut.

DETAILED DESCRIPTION OF THE INVENTION

The present invention describes a process for obtaining diesel fuel or kerosene from olefinic cuts, typically from a catalytic cracking unit of gasolines (abbreviated as FCC) and a BTX-rich fraction (abbreviation of benzene, toluene). , xylene) typically results from a semi-regenerative or regenerative reforming unit, generally present at the same site as the FCC unit.

By "typically" is meant the most frequent case that does not exclude other sources as described below.

The olefinic cut can also come from steam-cracking units (abbreviated as SC), Fischer Tropsch synthesis unit (abbreviated as FT), coking (denoted CK abbreviated) or a viscosity unit. reduction (noted VB abbreviated). The BTX-rich fraction can also come from a steam cracking unit (SC), a steam reforming unit (abbreviated as VR), an olefin cracking unit (abbreviated CO) or a transforming unit. methanol to olefins (abbreviated as MTO).

The feed to be treated (1) is a gasoline distillation range of between 30 ° C and 250 ° C. This charge is optionally sent to a SHU unit which makes it possible to selectively hydrogenate gum-forming unsaturated hydrocarbons, such as diolefins. The treated effluent (2) is sent directly or after distillation to a treatment unit (TR) based on the use of an acid catalyst, preferably a resin type catalyst ion exchange, as described in the patent FR 2.840.620 or of supported phosphoric acid type.

This step is intended to capture poisonous compounds acid catalysts, including nitrogen compounds, and optionally, to turn them into heavier compounds.

It has been observed, surprisingly, that the catalysts mentioned above, after a period of almost total capture of the nitrogenous compounds, continue to convert the nitrogen compounds of the feed into heavier compounds so that if a distillation is installed downstream of the treatment, the light cut obtained at the top of the distillation column is depleted in nitrogen. This light head cut can be treated without additional purification on downstream acid catalysts.

It has also been observed on this treatment step (TR), a heavier sulfur compounds so that the light cut resulting from the downstream distillation is also depleted of sulfur compounds.

1. a) une coupe de tête correspondant au flux (4) qui est envoyé dans l'enchainement d'unités oligomérisation (OLG) - alkylation sur BTX (ALK) en vue de produire une coupe (11) d'intervalle de distillation de type gazole qui est hydrogénée dans l'unité d'hydrogénation totale (HT) pour produire le distillat recherché (13),
2. b) une coupe intermédiaire (5) qui peut être envoyée dans une unité d'hydrodésulfuration permettant de réduire la teneur en soufre à moins de 10 ppm (non représentée sur la figure 1).

The effluent (3) of the resin treatment unit (TR) is sent to a distillation column (CD1) from which three cuts are extracted:

1. a) a head section corresponding to the flow (4) which is fed into the oligomerization unit (OLG) - alkylation on BTX (ALK) sequence to produce a diesel-type distillation range section (11) which is hydrogenated in the total hydrogenation unit (HT) to produce the desired distillate (13),
2. b) an intermediate cut (5) which can be sent to a hydrodesulfurization unit for reducing the sulfur content to less than 10 ppm (not shown in FIG. figure 1 ).

1. c) une coupe de fond (6) qui est envoyée dans une unité d'hydrotraitement sévère (HDT) permettant de réduire la teneur en soufre à moins de 10 ppm, d'hydrogéner la quasi totalité des oléfines, et de réduire significativement la teneur en aromatiques. L'effluent de l'unité d'hydrotraitement (HDT), noté flux (12), est envoyé vers l'unité d'hydrotraitement total (HT).

This type of unit is for example the unit known commercially under the name Prime G +, marketed by AXENS, a description of which can be found in the patent FR 2,797,639 .

1. c) a bottom cut (6) which is sent to a severe hydrotreatment unit (HDT) to reduce the sulfur content to less than 10 ppm, to hydrogenate almost all the olefins, and to significantly reduce the content in aromatics. The effluent of the hydrotreatment unit (HDT), noted flow (12), is sent to the total hydrotreatment unit (HT).

The head cut (4), optionally mixed with an LPG cut (10), is sent to an oligomerization unit (OLG) which will form oligomers with a number of carbon atoms of between 8 and 20 constituting the flow. (7).

• soit envoyé (flux 7a) vers l'unité d'hydrotraitement (HDT), lorsque sa teneur en soufre est supérieure à 10 ppm,
• soit envoyé (flux 7b) vers l'unité d'hydrogénation totale (HT) lorsque sa teneur en soufre est inférieure à 10 ppm.

According to its sulfur content, this stream (7) is:

• is sent (stream 7a) to the hydrotreating unit (HDT), when its sulfur content is greater than 10 ppm,
• is sent (stream 7b) to the total hydrogenation unit (HT) when its sulfur content is less than 10 ppm.

The oligomerization unit (OLG) operates on an acid catalyst of zeolitic or silica-alumina type, in a temperature range of 100 ° C to 350 ° C, and in a pressure range of 20 bars to 70 bars, and in a VVH range from 0.2h-1 to 1.0h-1.

The fraction of light olefins having a boiling point of less than 150 ° C. which has not reacted in the oligomerization unit (OLG) constitutes the stream (8) which feeds the alkylation unit (ALK). which uses a BTX cut (9) generally derived from a regenerative species reforming unit.

The alkylation unit of the olefins (8) from the oligomerization unit (OLG) on the BTX cut (9) operates on a zeolitic acid or silicoaluminate acid catalyst, in a temperature range of 100 ° C. at 350 ° C, and in a pressure range of 20 bar to 70 bar, and in a range of VHV from 0.1 hr-1 to 2.0 hr-1.

• une coupe essence (11a) de point d'ébullition inférieur à 100°C qui est envoyée vers le pool essence,
• une coupe intermédiaire (11b) d'intervalle de distillation compris entre 100°C et 150°C, essentiellement constituée des BTX n'ayant pas réagi et qui est en majorité recyclée à l'entrée de l'unité d'alkylation, à l'exception d'une fraction constituant la purge de l'unité et qui est elle même envoyée au pool essence après stabilisation,
• une coupe lourde (11c) de point d'ébullition supérieur à 150°C qui est envoyée à l'unité d'hydrogénation totale (HT) de laquelle est extrait le gazole recherché (13).

The effluent (11) of the alkylation unit (ALK) is sent to a distillation column (CD2) from which three cuts are extracted:

• a gasoline cut (11a) with a boiling point below 100 ° C which is sent to the gasoline pool,
• an intermediate cross-section (11b) of distillation range between 100 ° C and 150 ° C, essentially consisting of unreacted BTX and which is mostly recycled at the inlet of the alkylation unit, exception of a fraction constituting the purge of the unit and which is itself sent to the gasoline pool after stabilization,
• a heavy cut (11c) of boiling point greater than 150 ° C which is sent to the total hydrogenation unit (HT) from which is extracted the desired diesel (13).

EXAMPLE

The following example illustrates the process according to the invention.

Starting from a catalytic cracking gasoline feedstock and a BTX cut from a catalytic reforming unit. An LPG cut from the catalytic cracking unit is also added to this feed.

• essence (1): 100 t/h
• coupe BTX (9): 18 t/h
• coupe LPG(10): 25 t/h

The mass flow rates of the constituents of the load are as follows:

• petrol (1): 100 t / h
• BTX cut (9): 18 t / h
• LPG cut (10): 25 t / h

• pression 15 bars effectifs
• température 120°C
• catalyseur HR 945 commercialisé par la société Axens, avec une VVH de 2 h-1 l'essence hydrogénée (2) est introduite dans une unité de traitement sur catalyseur acide (TR) qui fonctionne aux conditions suivantes:
• pression 15 bars effectifs
• température 100 °C
• catalyseur TA 801 commercialisé par la société Axens, avec une VVH de 0,5 h-1

Gasoline (1) is introduced into a Selective Hydrogenation Unit (SHU) which operates under the following conditions:

• pressure 15 bars effective
• temperature 120 ° C
• HR 945 catalyst sold by the company Axens, with a VHV of 2 h -1 the hydrogenated gasoline (2) is introduced into an acid catalyst (TR) treatment unit which operates under the following conditions:
• pressure 15 bars effective
• temperature 100 ° C
• TA 801 catalyst marketed by the company Axens, with a VVH of 0.5 h -1

• en tête une coupe oléfinique (4) ayant un point final d'ébullition de 60°C,
• intermédiairement une coupe (5) d'intervalle de distillation compris entre 60°C et 150°C,
• en fond une coupe (6) de point d'ébullition supérieur à 150°C.

The effluent (3) of the unit TR is introduced into a distillation column (CD1) from which is separated:

• at the top an olefinic cut (4) having a boiling point of 60 ° C,
• intermediably a section (5) of distillation range between 60 ° C and 150 ° C,
• in bottom a section (6) with a boiling point greater than 150 ° C.

• pression: 60 bars effectifs
• température: 160 °C
• catalyseur IP 811 commercialisé par la société Axens, avec une VVH de 0,5 à 2 h-1.

The top cup (4) is mixed with a certain amount of LPG cup (10) and the resulting mixture is introduced into the oligomerization unit (OLG) which operates under the following conditions:

• pressure: 60 bars effective
• temperature: 160 ° C
• Catalyst IP 811 sold by the company Axens, with a VVH of 0.5 to 2 h -1.

• pression 20 bars effectifs
• température 300°C
• catalyseur HR 506 commercialisé par la société Axens, utilisé avec une VVH de 1 h-1. L'effluent (12) de l'unité d'hydrogénation (HDT) est envoyé vers l'unité d'hydrogénation totale (HT), éventuellement en mélange avec la partie (7b) de l'effluent oléfinique (7). L'effluent (13) de l'unité d'hydrogénation totale (HT) constitue la production de gazole recherché aux spécifications suivantes:
  • indice de cétane moteur : 45
  • densité 0,775 kg/m3

The oligomerization unit (OLG) produces on the one hand an effluent (7) consisting of oligomerized olefins which is partially (7a) mixed with the bottom section (6) of the distillation column (CD1). in a hydrotreating unit (HDT) operating under the following conditions:

• pressure 20 bars effective
• temperature 300 ° C
• HR 506 catalyst marketed by the company Axens, used with a VHV of 1 h-1. The effluent (12) of the hydrogenation unit (HDT) is sent to the total hydrogenation unit (HT), optionally mixed with the portion (7b) of the olefinic effluent (7). The effluent (13) of the total hydrogenation unit (HT) constitutes the desired diesel production with the following specifications:
  • cetane number motor: 45
  • density 0.775 kg / m3

The intermediate effluent (5) of the distillation column CD1 is sent to the gasoline pool.

• pression 2500 kPa (k est l'abréviation de kilo soit 10³ pascal)
• température 150°C
• catalyseur zéolithe Y,
• VSL : 2,5 h-1

The oligomerization unit (OLG) also produces an effluent (8) of C3 and C4 olefins which is fed with the BTX cut (9) into an alkylation unit (ALK) operating under the following conditions:

• pressure 2500 kPa (k is the abbreviation of kilo or 10 ³ pascal)
• temperature 150 ° C
• zeolite catalyst Y,
• VSL: 2.5 hrs-1

The effluent (11) of the alkylation unit (ALK) is sent to a second distillation column (CD2) which produces in the bottom an effluent (11c) which is sent to the total hydrogenation unit (HT). and thus contributes to the production of the desired diesel (13).

The lateral effluent (11b) of the distillation column (CD2) is returned to the alkylation unit (ALK). The overhead effluent (11a) of column CD2 is sent to the gasoline pool.

Tables A and B below give details of flows according to the scheme of the figure 1 .

Overall, the process according to the invention therefore produced 66 tonnes / hour of diesel (13), from 100 tonnes / hour of FCC gasoline (1), of 18 tonnes / hour of BTX cut (9) and 25 tonnes of gasoline. t / h FCC LPG cut (10), a yield (13) / (1) + (9) + (10) of 46% conversion of a gasoline cut into a distillate cut, usable as a kerosene base or of diesel.

• Cn désigne une coupe paraffinique à n atomes de carbone
• Cn⁼ désigne une coupe oléfinique à n atomes de carbone
• A désigne les aromatiques
• B désigne le benzène,
• T désigne le toluène, X désigne les xylènes
• les indices n,i,c signifient respectivement normale (ou linéaire), iso (ou ramifié) et cycliques.

TABLEAU "A" Feed Effluent SHU Effluent TR CD1 lights CD1 heart cut CD1 heavy cut Feed C4 Oligo Feed Oligo Prod Oligo heavies Oligo lights (1) (2) (3) (4) (5) (6) (10) (10)+(4) (8)+(7) (7) (8) C4(i,n) 0.05 0.08 0.08 0.08 - - 12.00 12.08 12.08 - 12.08 C4= 0.27 0.24 0.22 0.22 - - 13.00 13.22 0.66 - 0.66 C5(i,n,c) 10.49 11.14 11.14 11.14 - - - 11.14 11.14 - 11.14 C5= 13.10 12.74 11.47 11.47 - - - 11.47 1.72 - 1.72 C6(i,n,c) 8.57 8.77 8.77 0.88 7.90 - - 0.88 0.88 - 0.88 C6= 8.34 8.13 8.13 0.81 7.32 - - 0.81 0.20 - 0.20 B 0.94 0.94 0.94 - 0.94 - - - - - - C7(i,n,c) 6.28 6.28 6.28 - 6.28 - - - - - - C7= 3.61 3.61 3.61 - 3.61 - - - - - - T 4.87 4.87 4.87 - 4.87 - - - - - - C8(i,n,c) 4.09 4.09 4.09 - 4.09 - - - - - - C8= 1.64 1.64 1.64 - 1.64 - - - - - - X 9.70 9.70 9.70 - 9.70 - - - - - - C9(i,n,c) 1.85 1.85 1.85 - 0.56 1.30 - - - - - C9= 1.26 1.26 1.26 - 0.38 0.89 - - - - - A9 9.93 9.93 9.93 - 1.49 8.44 - - - - - C10(i,n,c) 1.90 1.90 1.90 - - 1.90 - - - - - C10= 0.84 0.84 0.84 - - 0.84 - - - - - A10 7.88 7.88 7.88 - - 7.88 - - - - - C11(i,n,c) 0.57 0.57 0.57 - - 0.57 - - - - - C11= 0.70 0.70 0.70 - - 0.70 - - - - - A11 1.28 1.28 1.28 - - 1.28 - - - - - C12(i,n,c) 0.46 0.46 0.46 - - 0.46 - - - - - C12= 0.14 0.14 0.14 - - 0.14 - - - - - A12 0.89 0.89 0.89 - - 0.89 - - - - - C12(i,n,c) 0.02 0.02 0.02 - - 0.02 - - - - - C12= - - - - - - - - - - A12 0.01 0.01 0.01 - - 0.01 - - - - - Oligomères C8-C12 - - 1.30 - 1.30 - - - 17.19 - 17.19 Oligomères C12-C16 - - - - - - - - 5.73 5.73 - Alkylate - - Dienes 0.33 0.03 0.03 - - 0.03 - - - - - HT oligomers C12-C15 - - HT Alkylate - - S(ppm pds) 1000 800 800 8 320 472 10 9 9 78 0 N(ppm pds) 30 27 14 0 3 11 1 1 1 5 0 Total 100.00 100.00 100.00 24.60 50.06 25.35 25.00 49.60 49.60 5.73 43.87 TABLEAU"B" Feed BTX BTX recycle Alky effluent Light purge Heart cut purge Heavy Product Heart cut to gasoline Oligo Heavies to HDT Oligo Heavies to HT HDT Effluent (après strippeur) (H2 feed non exemplifié) HT feed HDT Effluent (après strippeur) (H2 feed non exemplifié) (9) 11b)recycle (11) (11a) (11b) (11c) (11b)out (7a) (7b) (12a) (7b+12+11c) (13) C4(i,n) - - 12.08 12.08 - - - - - - - - C4= - - 0.01 0.01 - - - - - - - - C5(i,n,c) - - 11.14 11.14 - - - 11.14 - - - - C5= - - 0.02 0.02 - - - - - - - - C6(i,n,c) - - 0.88 0.88 - - - 0.88 - - - - C6= - - 0.00 0.00 - - - B - - - - - - - - - - - - C7(i,n,c) - - - - - - - - - - - - C7= - - - - - - - - - - - - T 14.00 68.55 70.67 - 70.67 - 2.12 - - - C8(i,n,c) - - - - - - - - - - - - C8= - - - - - - - - - - - - X 4.00 1.29 1.33 - 1.33 - 0.04 - - - - - C9(i,n,c) - - - - - - - - - 1.39 1.39 6.40 C9= - - - - - - - - - 0.80 0.80 - A9 - - - - - - - - - 8.44 8.44 4.22 C10(i,n,c) - - - - - - - - - 1.98 1.98 6.68 C10= - - - 0.76 0.76 - A10 - - - - - - - - - 7.88 7.88 3.94 C11(i,n,c) - - - - - - - - - 0.64 0.64 1.91 C11= - - - - - - - - - 0.63 0.63 - A11 - - - - - - - - - 1.28 1.28 0.64 C12(i,n,c) - - - - - - - - - 0.47 0.47 1.05 C12= - - - - - - - - - 0.13 0.13 - A12 - - - - - - - - - 0.89 0.89 0.45 C12(i,n,c) - - - - - - - - - 0.02 0.02 0.02 C12= - - - - - - - - - - - - A12 - - - - - - - - - 0.01 0.01 0.00 Oligomères C8-C12 - 3.64 3.75 - 3.75 - 0.11 - - - - - Oligomères C12-C16 - - 0.42 - - 0.42 - - 5.73 - 6.15 - Alkylate - - 35.06 - 0.00 35.06 0.00 - - - 35.06 - Dienes - - - - - - - - - 0.03 0.03 - HT oligomers C12-C15 - - - - - - - - - - - 6.15 HT Alkylate - - - - - - - - - - - 35.06 s(ppm pds) 0 0 0 0 0 0 0 0 78 12 11 1 N(ppm pds) 0 0 0 0 0 0 0 0 5 5 2 1 Total 18.00 73.48 135.35 24.12 75.76 35.47 2.27 - 5.73 25.35 66.55 66.61 For a good understanding of Tables A and B, we specify the meaning of the abbreviations used:

• Cn denotes a paraffinic cut with n carbon atoms
• Cn ⁼ denotes an olefinic cut with n carbon atoms
• A denotes the aromatics
• B is benzene,
• T is toluene, X is xylenes
• the indices n, i, c mean respectively normal (or linear), iso (or branched) and cyclic.

TABLE "A" Feed Effluent SHU TR Effluent CD1 lights CD1 heart cut CD1 heavy cut Feed C4 Oligo Feed Oligo Prod Oligo heavies Oligo lights (1) (2) (3) (4) (5) (6) (10) (10) + (4) (8) + (7) (7) (8) C4 (i, n) 0.05 0.08 0.08 0.08 - - 12.00 12.08 12.08 - 12.08 C4 = 0.27 0.24 0.22 0.22 - - 13.00 13.22 0.66 - 0.66 C5 (i, n, c) 10.49 11.14 11.14 11.14 - - - 11.14 11.14 - 11.14 C5 = 13.10 12.74 11.47 11.47 - - - 11.47 1.72 - 1.72 C6 (i, n, c) 8.57 8.77 8.77 0.88 7.90 - - 0.88 0.88 - 0.88 C6 = 8.34 8.13 8.13 0.81 7.32 - - 0.81 0.20 - 0.20 B 0.94 0.94 0.94 - 0.94 - - - - - - C7 (i, n, c) 6.28 6.28 6.28 - 6.28 - - - - - - C7 = 3.61 3.61 3.61 - 3.61 - - - - - - T 4.87 4.87 4.87 - 4.87 - - - - - - C8 (i, n, c) 4.09 4.09 4.09 - 4.09 - - - - - - C8 = 1.64 1.64 1.64 - 1.64 - - - - - - X 9.70 9.70 9.70 - 9.70 - - - - - - C9 (i, n, c) 1.85 1.85 1.85 - 0.56 1.30 - - - - - C9 = 1.26 1.26 1.26 - 0.38 0.89 - - - - - A9 9.93 9.93 9.93 - 1.49 8.44 - - - - - C10 (i, n, c) 1.90 1.90 1.90 - - 1.90 - - - - - C10 = 0.84 0.84 0.84 - - 0.84 - - - - - A10 7.88 7.88 7.88 - - 7.88 - - - - - C11 (i, n, c) 0.57 0.57 0.57 - - 0.57 - - - - - C11 = 0.70 0.70 0.70 - - 0.70 - - - - - A11 1.28 1.28 1.28 - - 1.28 - - - - - C12 (i, n, c) 0.46 0.46 0.46 - - 0.46 - - - - - C12 = 0.14 0.14 0.14 - - 0.14 - - - - - AT 12 0.89 0.89 0.89 - - 0.89 - - - - - C12 (i, n, c) 0.02 0.02 0.02 - - 0.02 - - - - - C12 = - - - - - - - - - - AT 12 0.01 0.01 0.01 - - 0.01 - - - - - Oligomers C8-C12 - - 1.30 - 1.30 - - - 17.19 - 17.19 Oligomers C12-C16 - - - - - - - - 5.73 5.73 - alkylate - - Dienes 0.33 0.03 0.03 - - 0.03 - - - - - HT oligomers C12-C15 - - HT Alkylate - - S (ppm wt) 1000 800 800 8 320 472 10 9 9 78 0 N (ppm wt) 30 27 14 0 3 11 1 1 1 5 0 Total 100.00 100.00 100.00 24.60 50.06 25.35 25.00 49.60 49.60 5.73 43.87 BTX Feed BTX recycles Alky effluent Light purge Heart cut purge Heavy Product Heart cut to gasoline Oligo Heavies to HDT Oligo Heavies to HT HDT Effluent (after stripper) (H2 feed not exemplified) HT feed HDT Effluent (after stripper) (H2 feed not exemplified) (9) 11b) recycles (11) (11a) (11b) (11c) (11b) out (7a) (7b) (12a) (7b 12 + + 11c) (13) C4 (i, n) - - 12.08 12.08 - - - - - - - - C4 = - - 0.01 0.01 - - - - - - - - C5 (i, n, c) - - 11.14 11.14 - - - 11.14 - - - - C5 = - - 0.02 0.02 - - - - - - - - C6 (i, n, c) - - 0.88 0.88 - - - 0.88 - - - - C6 = - - 0.00 0.00 - - - B - - - - - - - - - - - - C7 (i, n, c) - - - - - - - - - - - - C7 = - - - - - - - - - - - - T 14.00 68.55 70.67 - 70.67 - 2.12 - - - C8 (i, n, c) - - - - - - - - - - - - C8 = - - - - - - - - - - - - X 4.00 1.29 1.33 - 1.33 - 0.04 - - - - - C9 (i, n, c) - - - - - - - - - 1.39 1.39 6.40 C9 = - - - - - - - - - 0.80 0.80 - A9 - - - - - - - - - 8.44 8.44 4.22 C10 (i, n, c) - - - - - - - - - 1.98 1.98 6.68 C10 = - - - 0.76 0.76 - A10 - - - - - - - - - 7.88 7.88 3.94 C11 (i, n, c) - - - - - - - - - 0.64 0.64 1.91 C11 = - - - - - - - - - 0.63 0.63 - A11 - - - - - - - - - 1.28 1.28 0.64 C12 (i, n, c) - - - - - - - - - 0.47 0.47 1.05 C12 = - - - - - - - - - 0.13 0.13 - AT 12 - - - - - - - - - 0.89 0.89 0.45 C12 (i, n, c) - - - - - - - - - 0.02 0.02 0.02 C12 = - - - - - - - - - - - - AT 12 - - - - - - - - - 0.01 0.01 0.00 Oligomers C8-C12 - 3.64 3.75 - 3.75 - 0.11 - - - - - Oligomers C12-C16 - - 0.42 - - 0.42 - - 5.73 - 6.15 - alkylate - - 35.06 - 0.00 35.06 0.00 - - - 35.06 - Dienes - - - - - - - - - 0.03 0.03 - HT oligomers C12-C15 - - - - - - - - - - - 6.15 HT Alkylate - - - - - - - - - - - 35.06 s (ppm wt) 0 0 0 0 0 0 0 0 78 12 11 1 N (ppm wt) 0 0 0 0 0 0 0 0 5 5 2 1 Total 18.00 73.48 135.35 24.12 75.76 35.47 2.27 - 5.73 25.35 66.55 66.61

Claims (4)

1. Process for the production of diesel fuel from a gasoline fraction that contains 5 to 10 carbon atoms and in a preferred manner 5 to 7 carbon atoms originating from a catalytic cracking unit (1), and a BTX fraction (9) that typically originates from a unit for catalytic reforming of gasolines, relying on the concatenation of the following stages:

   - a stage 1 for selective hydrogenation (SHU) of the initial gasoline fraction,

   - a stage 2 for treatment on the acid catalyst (TR) of the effluent that is obtained from stage 1,

   - a stage 3 for distillation of the effluent of stage 2 that is produced in a first distillation column (CD1) that makes it possible to separate at the top an olefinic fraction (4) that has a final boiling point of approximately 60°, intermediately a distillation interval fraction (5) of between 60°C and 150°C, and at the bottom a fraction (6) with a boiling point that is greater than 150) C, which is sent to a hydrotreatment (HDT) unit,

   - a stage 4 for oligomerization (OLG) of the olefinic fraction (4), optionally mixed with an LPG fraction (10) that contains olefins, from which, after distillation, a stream (7) of oligomerized olefins with a number of carbon atoms that ranges from 8 to 20 is sent for a first part (7a) to the hydrotreatment (HDT) unit and for a second part (7b) to a total hydrogenation (HT) unit is extracted,

   - a stage 5 for alkylation of the stream (8) of olefins into C3 and C4 obtained from stage 4 for oligomerization on the BTX fraction (9) that is rich with aromatic compounds containing 6 to 12 carbon atoms, and in a preferred manner 6 to 9 carbon atoms, whereby the effluent (11) of the alkylation (ALK) unit is sent into a second distillation column (CD2) from which 3 fractions are extracted:

   - a gasoline fraction (11a) with a boiling point that is less than 100°C, which is sent to the gasoline pool,

   - an intermediate fraction (11b) with a distillation interval of between 100°C and 150°C, essentially consisting of BTX that has not reacted, which is for the most part recycled at the input of the alkylation unit, with the exception of a fraction (11d) that constitutes the purging of the (ALK) unit, and which is itself sent to the gasoline pool after stabilization,

   - a heavy fraction (11c) with a boiling point that is greater than 150°C that is sent to the total hydrogenation (HT) unit from which the desired diesel fuel (13) is extracted,

   with the oligomerization stage 4 working on a preferably zeolitic- or silica-alumina-type acid catalyst, in a temperature range of 100°C to 350°C, and in a pressure range of 20 to 70 bar, and in a WH range of 0.2 to 1.0 h-1,
   and with alkylation stage 5 working on a preferably zeolitic- or silicoaluminate-type acid catalyst in a temperature range of 100 to 350°C, and in a pressure range of 20 to 70 bar, and in a WH range of 0.1 h-1 to 2.0 h-1.
2. Process for the production of diesel fuel according to claim 1, in which the stage 2 for treatment on an acid catalyst relies on an ion-exchange resin-type acid catalyst, or supported phosphoric acid catalyst, or any acid catalyst previously used in the downstream stages of oligomerization (OLG) or alkylation (ALK), in a temperature range of 20°C to 350°C, in a preferred manner of 40 to 250°C, and in a pressure range of 1 to 100 bar, in a preferred manner 10 to 30 bar, and in a WH range of 0.1 to 5 h-1, in a preferred manner 0.3 to 2.0 h-1.
3. Process for the production of distillates according to claim 1, in which the hydrotreatment (HDT) stage uses a catalyst that contains at least one metal that is selected from among Ni, Co and Mo and operates in a temperature range of 50 to 400°C, in a preferred manner 100 to 350°C, and in a pressure range of 1 to 100 bar, in a preferred manner 20 to 70 bar, and in a VVH range of 0.1 h-1 to 10 h-1, in a preferred manner 0.5 h-1 to 5.0 h-1.
4. Process for the production of distillates according to claim 1, in which the hydrotreatment (HDT) stage uses a catalyst that contains at least one metal that is selected from among Pd and Pt and operates within a temperature range of 50 to 300°C, in a preferred manner 100°C to 250°C, and in a pressure range of 1 to 100 bar, in a preferred manner 20 to 70 bar, and in a VVH range of 0.1 h-1 to 10 h-1, in a preferred manner 0.5 h-1 to 5.0 h-1.

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