RU2592693C2 - Method of converting hydrocarbon material containing shale oil, by removal of contaminants, hydroconversion in fluidised bed and fractionation using atmospheric distillation - Google Patents

Abstract

FIELD: technological processes.

SUBSTANCE: invention relates to a method of conversion of shale oil or a mixture of shale oil with nitrogen content at least 0.1 wt%, comprising following stages: a) raw material is subjected to removal of contaminants to produce residue and oil, cleaned from impurities, b) oil, cleaned from impurities, is introduced into hydroconversion part in presence of hydrogen, wherein said part comprises at least one reactor with fluidised bed, which operates in mode of gaseous and liquid flow and containing at least one hydroconversion catalyst on a substrate, c) output stream obtained at step b) is fed at least partially into fractionation zone, from which, by means of atmospheric distillation, come out gaseous fraction, naphtha fraction, gas oil fraction and fraction heavier than gas oil, d) said naphtha fraction is processed at least partially in other part for hydrotreatment in presence of hydrogen, wherein said part comprises at least one reactor with fixed layer, containing at least one hydraulic treatment catalyst, and e) said gas oil fraction is processed at least partially in part for hydrotreatment in presence of hydrogen, wherein said part comprises at least one reactor with fixed layer, containing at least one hydraulic treatment catalyst. Invention also relates to shale oil processing using said method.

EFFECT: invention provides maximisation of output fuel base.

25 cl, 2 dwg, 2 tbl, 1 ex

Description

The present invention relates to a method for converting shale oil-containing hydrocarbons into lighter products that can be used as fuel and / or petrochemical feedstocks. More specifically, the present invention relates to a method for the conversion of hydrocarbon feeds containing shale oil, which comprises a step for removing contaminants, a step for hydroconversion of the cleaned oil from the contaminants in a fluidized bed, followed by a fractionation step using atmospheric distillation to obtain a light fraction, a naphtha fraction and a gas oil fraction and obtaining a heavier fraction than the gas oil fraction, and specialized hydrotreatment for each of the naphtha and gas oil fractions. This method makes it possible to convert shale oils into a very high quality fuel base and, more specifically, has an excellent yield.

Due to the high volatility of prices per barrel and a decrease in the discovery of conventional areas of oil products, oil companies are turning to non-standard sources. Following oil and gas sands and deep-sea areas, oil shales, although relatively poorly known, are becoming increasingly desirable.

Oil shales are sedimentary rocks that contain an insoluble organic matter called kerogen. At a high temperature in situ or ex situ (″ distillation in retort ″) in the absence of air, at temperatures from 400 to 500 ° C, these shales give off oil, shale oil, a general form similar to crude oil.

Despite its composition other than crude oil, shale oils can be a substitute for the latter, as well as a source of chemical intermediates.

Shale oils cannot be directly used in place of crude oil. In fact, although these oils are similar to oil in some respects (for example, a similar H / C ratio), they differ in chemical nature and a much higher level of metallic and / or non-metallic impurities, thus making the conversion of this non-standard source much more complex than oil. Shale oils have, in particular, oxygen and nitrogen levels that are much higher than in oil. They may also contain higher concentrations of olefins, sulfur, or metal compounds (especially compounds containing arsenic).

Shale oils obtained by pyrolysis of kerogen contain a large number of olefin compounds obtained as a result of cracking, and this leads to the need for additional hydrogen at the stage of purification. For example, the bromine index, which makes it possible to calculate the concentration by weight of olefinic hydrocarbons (by adding bromine to the ethylene double bond), is usually greater than 30 g / 100 g of hydrocarbon feed for shale oils, while it is from 1 to 5 g / 100 g of hydrocarbon feed for oil residues. The olefin compounds resulting from cracking essentially consist of monoolefins and diolefins. The unsaturations present in olefins are a potential source of instability during polymerization and / or oxidation.

The oxygen content, as a rule, is higher than in heavy oil, and can be almost 8 wt.% From raw materials. Oxygen compounds are often phenols and carboxylic acids. Therefore, shale oils can have a noticeable acidity.

The sulfur content varies from 0.1 wt.% To 6.5 wt.%, Making strong desulfurization treatments necessary to meet the specifications for the fuel base. Sulfur compounds are in the form of thiophenes, sulfides or disulfides. Moreover, the sulfur distribution profile in shale oil may differ from that obtained in conventional oil.

The most distinctive feature of shale oils, however, is the higher nitrogen content, which makes them unsuitable as conventional raw materials for a refinery. Oil typically contains about 0.2 wt.% Nitrogen, while crude shale oils contain, as a rule, about 1 wt.% To about 3 wt.% Or more nitrogen. Moreover, nitrogen compounds present in oil are generally concentrated in relatively higher boiling ranges, while nitrogen compounds present in crude shale oils are generally distributed over all boiling ranges of the material. Nitrogen compounds in oil are mainly minor compounds, while, in general, about half of the nitrogen compounds present in crude shale oils are basic. These basic nitrogen compounds are particularly undesirable in petroleum refining feeds, as these substances often act as catalyst poisoning agents. In addition, product stability is a problem that is common to many products derived from shale oil. Such instability, including photosensitivity, as it turned out, is essentially the result of the presence of nitrogen compounds. Consequently, crude shale oils should typically undergo a strong refining treatment (high total pressure) in order to obtain synthetic crude oil or fuel base products that meet the current conditions.

It is also known that shale oils can contain many traces of metal compounds, generally present in the form of organometallic complexes. Metal compounds include common pollutants such as nickel, vanadium, calcium, sodium, lead or iron, as well as arsenic metal compounds. In fact, shale oils may contain more than 20 ppm of arsenic, while the amount of arsenic in crude oil typically lies in the ppm range (ppm). All of these metal compounds are catalyst poisoners. More specifically, they irreversibly poison hydroprocessing catalysts and hydrogenation catalysts by uniform deposition on the active surface. Conventional metal compounds and part of arsenic are found mainly in heavy fractions and are removed by precipitation on the catalyst. On the other hand, when products containing arsenic are capable of creating volatile compounds, these compounds can be partially found in lighter fractions and, as a result, can poison the catalysts in subsequent conversion processes, during refining, or in petrochemicals.

In addition, shale oils typically contain sandy sediments originating from areas of tar shale, from which shale oils are extracted. These sand deposits can cause clogging problems, especially in fixed bed reactors.

Finally, shale oils may contain waxes that make their pour point higher than the ambient temperature, thus preventing them from moving in the pipeline.

In view of the significant resources and in view of their evaluation as a promising source of oil, there is a true need for turning shale oils into light products that can be used as fuel and / or raw materials for petrochemicals. Methods for the conversion of shale oils are known. Conversion is usually carried out in practice, alternatively by coking, hydrocracking (thermal cracking in the presence of hydrogen) or by hydroconversion (catalytic hydrogenation). Liquid / liquid extraction processes are also known.

For example, patent document CA 2605056 describes a process for the conversion of heavy feedstocks having an initial boiling point of more than 340 ° C, where the feedstock undergoes a deasphalting step, and then the resulting refined petroleum product is subjected to hydroconversion in the presence of a dispersed catalyst. The refined oil product that has not undergone hydroconversion is recycled to the deasphalting stage. The raw materials mentioned in this document refer exclusively to the type of fuel oil and tar obtained from ordinary oil. One deasphalting stage is provided for atmospheric gas oil cutting. The next stage of vacuum distillation with recycling of the residue in vacuum is shown.

Patent Document CA 2464796 describes a process for the conversion of heavy feeds, which is similar to the method according to the above CA 2605056. There is no reference to shale oil treatment in CA 2464796; the raw materials in question are only fuel oil and tar. Moreover, a vacuum distillation step is optional. Finally, in this method there is no residue recycling.

US 2007138058 describes a slurry hydroconversion process in which a feed is subjected to an initial hydrotreatment or deasphalting step. Transformed products undergo a non-specific hydrotreating operation. The described method is applied to various heavy raw materials obtained from conventional oil. Shale oils are not mentioned here.

Patent application US 2004163996 relates to a method for processing fuel oil or tar, wherein said residue is subjected to a deasphalting step and then fractionated into deasphalted oil (refined oil product) and asphalt (extract), which are individually subjected to hydroconversion using a fluidized bed process.

The patent application US 2009166253 provides for the connection of a number of stages of deasphalting, followed by a stage of hydrocracking of one or more deasphalted oils, after which they are fractionated. The method is used for various raw materials, including shale oil.

Object of the invention

The specific feature of shale oils, consisting of a certain number of metallic and / or non-metallic impurities, makes the conversion of this non-standard source much more difficult than oil. The industrial development of methods for converting shale oils therefore needs to develop methods that are suitable for raw materials that maximize the output of a high quality fuel base. Conventional cleansing treatments known to oil should be adapted to the specific composition of shale oils.

The present invention contributes to the improvement of known methods for the conversion of hydrocarbon materials containing shale oil by increasing, in particular, the yield of the fuel base for a combination of steps having a specific bond and processing corresponding to each fraction obtained from shale oils. Similarly, it is an object of the present invention to provide high quality products having, more specifically, a low content of sulfur, nitrogen and arsenic, preferably as described. Another objective is to provide a method that is simple, that is, it has as few stages as necessary, while remaining efficient, allowing you to limit the cost of investment.

In its broadest form and according to a first aspect, the present invention relates to a method for converting hydrocarbon feedstocks containing at least one shale oil having a nitrogen content of at least 0.1%, often at least 1% and very often at least 2 wt.% , characterized in that it contains the following stages:

a) the raw material is subjected to the removal of contaminants to obtain a residue and an oil purified from contamination,

b) an oil purified from contaminants is introduced into the gyroconversion part in the presence of hydrogen, said part comprising at least one fluidized bed reactor operating in a gaseous and liquid ascending mode and containing at least one hydroconversion catalyst on a substrate,

c) the effluent obtained in step b) is introduced at least partially, and often completely, into the fractionation zone, from which, through atmospheric distillation, a gaseous fraction, a ligroin fraction, a gas oil fraction and a heavier fraction than gas oil leave

d) said ligroin fraction is processed at least partially, and often completely, in another part for hydrotreatment in the presence of hydrogen, said part containing at least one fixed-bed reactor containing at least one hydrotreatment catalyst, and

e) said gas oil fraction is processed at least partially, and often completely, in a hydrotreatment portion in the presence of hydrogen, said portion comprising at least one fixed bed reactor comprising at least one hydrotreatment catalyst.

The hydroconversion part in step b) typically contains from one to three, preferably two, reactors in series, and the first and second hydrotreatment parts in steps d) and e), as a rule, each independently contains from one to three reactors in series.

The method preferably comprises an additional step f), in which a fraction heavier than gas oil is recycled to step a) to remove impurities.

The research work carried out by the authors on the conversion of shale oils led to the discovery that the improvement of existing methods, in terms of the output of the fuel base and in terms of product purity, is possible by combining various stages connected in a special way. Each fraction obtained by the method according to the present invention is sequentially introduced into the processing part.

In the first phase, the hydrocarbon feed containing shale oil is subjected to the removal of contaminants, which are preferably in the form of deasphalting, using a solvent in the form of a C ₃ -C ₅ hydrocarbon, alone or as a mixture. The solvent is selected to separate asphalt, which contains heavy aromatic compounds that will be insoluble in the solvent. The extraction step also helps to reduce the proportion of aromatic nitrogen compounds that are resistant to hydrodenitrification (denitrogenation by catalytic hydrogenation), the removal of particles and minerals derived from tar shale, and the capture of a large part of heavy organometallic compounds containing metals such as vanadium or nickel. These heavy organometallic compounds may contain porphyrin constituents within them, which are responsible for the separation of metals. Deasphalting is carried out on all raw materials in order to maximize the extraction of aromatic nitrogen compounds present in fractions in the range from LPG to a fraction heavier than gas oil. The use of deasphalting on all raw materials before hydroconversion helps to remove most of the metal poisoning agents present in the raw materials, more specifically arsenic, as well as heavy nitrogen compounds, which are usually aromatic. Accordingly, the rate of renewal of the hydroconversion catalyst is reduced, and hydrogen requirements are limited due to the reduced presence of compounds that are converted to deasphalted oil. Examples of aromatic nitrogen compounds that can be found in raw materials capable of being processed by the method of the present invention include pyridines, pyrimidines, pyrazines, quinolines, isoquinolines, pyrroles, imidazoles and other monocyclic or polycyclic aromatic nitrogen heterocycles. These aromatic nitrogen compounds may have substituents in the form of various hydrocarbon chains, possibly containing heteroatoms, such as nitrogen, oxygen and sulfur.

The second stage contains fluidized bed hydroconversion. The fluidized bed technique, relative to the fixed bed method, facilitates the processing of raw materials that are heavily contaminated with metals, heteroatoms and precipitates, such as shale oils, while exhibiting a conversion rate that is typically greater than 50%. In fact, in the second stage, shale oil turns into molecules that are capable of creating a fuel base in the future. Most metal compounds, residues and heterocyclic compounds are removed. The stream leaving the fluidized bed thus contains most of the stable nitrogen and sulfur compounds and possibly the volatile arsenic compounds that are present in the lighter components.

The effluent obtained in the hydroconversion stage is then fractionated by atmospheric distillation, creating various fractions for which a treatment specific to each fraction is successively carried out. Atmospheric distillation facilitates the production, at the first stage, of various desired fractions (naphtha, gas oil), thus facilitating the downstream hydrotreatment adapted for each fraction and, therefore, the direct production of gas oil or naphtha fuel base products that satisfy different technical conditions. Therefore, fractionation after hydroprocessing is not necessary.

Due to the high level of reduction of pollution in the fluidized bed, light fractions (naphtha and gas oil) contain less pollutants and can therefore be processed in parts with a fixed layer, which, as a rule, has improved hydrogenation kinetics compared to the fluidized bed. Similarly, operating conditions can be mild due to the limited pollutant content. Processing for each fraction allows better performance with respect to the desired products. Depending on the selected operating conditions (more or less strict), it is possible to obtain either a fraction that can be introduced into the fuel pool, or a final product that satisfies the current technical specifications (sulfur content, maximum smoke height, cetane, aromatic components, etc.). d.).

Upstream of the hydroprocessing catalyst bed, the fixed-bed hydroprocessing portions preferably contain specific protective layers for any arsenic compounds or silicon compounds contained within the diesel engine and / or naphtha. Arsenic compounds released from the fluidized bed (because they are usually relatively volatile) are captured by the protective layers, thus preventing the poisoning of downstream catalysts and contributing to the production of a very arsenic depleted fuel base.

Atmospheric distillation also contributes to the concentration of most stable nitrogen compounds in the fraction, which is heavier than gas oil, and which is introduced in stage f) to stage a) for deasphalting. Accordingly, this stage of recycling contributes to the suppression of the fraction heavier than gas oil, and therefore makes it possible to minimize the problems of utilization and economic yields of this fraction. A fraction that is heavier than gas oil may be introduced into step a), at least partially, preferably completely.

Asphalts are used in the production of heavy fuel oils and bitumen.

DETAILED DESCRIPTION OF THE INVENTION

Hydrocarbon feed

The hydrocarbon feed contains at least one shale oil or a mixture of shale oils. The term "shale oil" is used in this application in its broadest sense and is intended to include any shale oil or a fraction of shale oil that contains nitrogen impurities. It includes crude shale oil, obtained either by pyrolysis, by solvent extraction, or other means, or shale oil that has been filtered to remove solids or which has been treated with one or more solvents, chemicals or other treatments, and which contains nitrogen impurities . The term "shale oil" also contains shale oil fractions obtained by distillation or other fractionation technique.

The shale oils used according to the present invention typically have a Conradson carbon residue of at least 0.1 wt.% And, as a rule, at least 5 wt.%, An asphaltene content (IP143 standard / s C7) of at least 1 %, often at least 2 wt.%. The sulfur content in them, as a rule, is at least 0.1%, often at least 1% and very often at least 2%, and even up to 4% or even 7 wt.%. The amount of metals that they contain is typically at least 5 parts per million, often at least 50 parts per million, and typically at least 100 parts per million, or at least 200 parts by weight per million. The nitrogen content in them, as a rule, is at least 0.5%, often at least 1% and very often at least 2 wt.%. The arsenic content in them, as a rule, is more than 1 mass parts per million and up to 50 mass parts per million.

The method according to the present invention is intended for the conversion of shale oils. However, the feed may optionally contain, in addition to shale oil, other synthetic liquid hydrocarbons, more particularly those containing a substantial amount of cyclic organic nitrogen compounds. This includes oils derived from coal, oils based on heavy resins, tar sands, pyrolytic oils from wood residues such as wood residues, crude oil derived from biomass (би bio-raw materials ’), vegetable oils and animal fats.

Other hydrocarbon feedstocks may also provide shale oil. The feedstock is selected from the group consisting of vacuum distillates and direct distillation residues, vacuum distillates and unconverted residues obtained during conversion processes, such as, for example, obtained during distillation to a coke point (coking), products obtained from hydroconversion of heavy fractions with fixed layer, products obtained from the hydroconversion process of heavy fractions with a fluidized bed, and oils deasphalted using solvents (for example, oils deasphalted with propane, butane and foam tan, occurring during the process of deasphalting of vacuum residues of direct distillation or vacuum residues obtained from hydroconversion processes). The feed may further comprise light cyclic oil (LCO) of various origins, heavy cyclic oil (LCO) of various origins, and gas oil fractions that originate from catalytic cracking and typically have a distillation range of from about 150 ° C to about 650 ° C . The feed may also contain aromatic extracts obtained from the production of lubricating oils. Raw materials can also be obtained and used in mixtures, in any proportions.

Hydrocarbons added to shale oil or to a mixture of shale oils can comprise from 20% to 60% by weight of all raw materials (shale oil or a mixture of shale oils + added hydrocarbons), or from 10% to 90% by weight.

Contamination removal

Hydrocarbon feeds containing shale oil are sent to the contaminant removal step [step a)]. The objective of this stage is the extraction of pollutant-rich compounds. These pollutants contain heavy compounds rich in heteroatoms such as nitrogen, oxygen and sulfur, as well as most of the metals present in the feed.

One preferred method for removing contaminants is deasphalting.

Such contaminant removal can be carried out by extraction with a solvent or by ultrafiltration on a membrane, for example Zr on carbon, for example, in the presence of supercritical CO ₂ (C. Rodriguez et al. Desalination 144 (2002), 173-178).

Solvent deasphalting is carried out under conditions that are well known to those skilled in the art. Methods that can be used include, for example, the Solvahl method from Axens or the Rose method from KBR.

Deasphalting is traditionally carried out using an aliphatic solvent, usually C ₃ -C ₇ , preferably C ₃ -C ₅ , alkane or cycloalkane, or mixtures thereof in any proportions.

The removal of contaminants in step a) is carried out using a solvent selected from the group consisting of propane, n-butane, isobutane, n-pentane, cyclopentane, 2-methylbutane, 2,2-dimethylpropane, and mixtures thereof in any proportions.

Deasphalting can be carried out by any means known to a person skilled in the art. Extraction is usually carried out in a mixer-settler or in an extraction column. The extraction is preferably carried out in an extraction column.

The operating conditions are typically a solvent / feed ratio of 3/1 to 8/1 vol.% / Vol.%, Preferably 4/1 to 6/1 vol.% / Vol.%, And a temperature profile of 60 to 250 ° C, preferably from 60 ° C to 200 ° C. The operating pressure should be maintained at a value higher than the critical pressure of the solvent used. Preferably from 4 to 5 MPa.

In one preferred embodiment of the present invention, a mixture containing a hydrocarbon feed and a first solvent charge fraction is introduced into the extraction column, wherein the volume ratio between the solvent charge fraction and the hydrocarbon feed is called the level of solvent injected into the feed. The objective of this step is to induce efficient mixing of the feed with the solvent entering the extraction column. In the deposition zone at the bottom of the extractor, a fraction of the second solvent charge may be introduced, the volume ratio between the second charge fraction and the hydrocarbon feed being called the level of solvent injected at the bottom of the extractor. The volume of hydrocarbon feed in the deposition zone is typically the level introduced into the extraction column. The sum of the two volume relationships between each of the solvent charge fractions and the hydrocarbon feed is generally referred to as the solvent level. Asphalt sedimentation includes countercurrent washing of the asphalt emulsion in a solvent + oil mixture with a pure solvent. This is facilitated by an increase in solvent level (the procedure actually involves replacing the solvent + oil medium with a pure solvent medium) and lowering the temperature.

The solvent can be removed either by evaporation of the solvent (many stages of flash evaporation with decreasing pressure and increasing temperature), usually followed by distillation of the low boiling fractions with water vapor or by applying the procedure of separating the solvent at a pressure higher than the critical pressure of the solvent or higher than the pressure of the deasphalted oil / solvent mixture, thereby reducing the energy cost of evaporation.

Extraction provides raw materials with a reduced nitrogen content, and this content is approximately half in relation to the nitrogen content of the raw material. At least a portion, and preferably all, of the asphalt oil is introduced into the fluidized bed reactor for hydroconversion in the presence of hydrogen. The fluidized bed contains a hydroconversion catalyst on a support.

According to a preferred embodiment of the present invention, asphalt is introduced into a part of the vapor-oxygen gasification, in which it is converted into a gas containing hydrogen and carbon monoxide. This gas mixture can be used for the synthesis of methanol or for the synthesis of hydrocarbons through the Fischer-Tropsch reaction. This mixture, in the context of the present invention, is preferably introduced into the “shift” conversion (steam conversion) section, in which, in the presence of steam, it is converted to hydrogen and carbon dioxide. The hydrogen produced can be used in steps b), d) and e) of the process of the present invention. The asphalt obtained in step a) can also be used as solid fuel or, after fluxing, as liquid fuel, or can form part of the composition of bitumen (after an optional purge step) and / or heavy fuel oils.

Deasphalting of raw materials therefore makes it possible to extract stable aromatic compounds containing nitrogen and pollutants (metals), as well as particles and sediments, which sometimes make up to 0.2 wt.% Of the raw materials. The implementation of the primary stage of deasphalting of raw materials ensures the preservation of the hydroconversion catalyst used in the next stage and minimizes the continuous replenishment of the catalyst.

Hydroconversion

After removal of contaminants by deasphalting, the obtained refined oil product (deasphalted oil or DAO, or raw material purified from contaminants) undergoes a fluidized bed hydroconversion stage [stage b)]. Hydroconversion is understood as hydrogenation, hydrotreatment, hydrodesulfurization, hydrodenitrogenation, hydrodemetallization and hydrocracking reactions.

The operation of a fluidized bed catalytic reactor, including the recycling of liquids from the reactor to the top through a stirred catalytic bed, is well known. Fluidized bed techniques employ catalysts on a substrate, typically in the form of extrudates, having a diameter of typically about 1 mm or less than 1 mm, for example greater than or equal to 0.7 mm. Catalysts remain inside reactors and are not removed with products. The catalytic activity may remain constant due to the continuous substitution (addition and withdrawal) of the catalyst. Therefore, there is a need to shut down the assembly in order to replace the used catalyst, or to increase the reaction temperature during the cycle to compensate for deactivation. Moreover, working with constant working conditions makes it possible to coordinate product quality and yields obtained per catalyst cycle. Since the catalyst is kept in a state of mixing through substantial liquid recycling, the pressure loss across the reactor remains low and constant, and the heat of reaction is quickly averaged over the catalyst bed, which is therefore almost isothermal and does not require cooling by injection of quenchers. The fluidized bed hydroconversion avoids the problems of catalyst contamination associated with the deposition of impurities naturally present in shale oils.

The conditions in step b) of processing the feed in the presence of hydrogen are standard fluidized bed hydroconversion conditions for a liquid hydrocarbon fraction. They usually operate at a total pressure of from 2 to 35 MPa, preferably from 10 to 20 MPa, at a temperature of from 300 ° C to 550 ° C and often from 400 ° C to 450 ° C. The hourly average feed rate (HSV) and the partial pressure of hydrogen are important factors that are selected according to the characteristics of the product to be processed and the desired conversion. HSV, as a rule, lies in the range from 0.2 h ^-1 to 1.5 h ^-1 and preferably from 0.4 h ^-1 to 1 h ^-1 . The amount of hydrogen mixed with the feed is typically from 50 to 5000 normal cubic meters (Nm ³ ) per cubic meter (m ³ ) of liquid feed, and typically from 100 to 1000 Nm ³ / m ³ , preferably from 300 to 500 Nm ³ / m ³ .

This hydroconversion step b) can typically be carried out under the conditions of the T-STAR® process, as described, for example, in Heavy Oil Hydroprocessing published by AlChE, March 19-23, 1995, Houston, Texas, paper number 42d. It can also be carried out under the conditions of the H-OIL® process, as described, for example, in an article published by NPRA, Annual Meeting, March 16-18, 1997, J.J. Colyar and L.I. Wisdom called The H-Oil® Process, A Worldwide Leader In Vacuum Residue Hydroprocessing.

The hydrogen required for hydroconversion (and subsequent hydrotreatment operations) can come from steam reforming of hydrocarbons (methane) or from gas obtained from oil shale during the production of shale oils.

The catalyst in step b) is preferably a conventional granular hydroconversion catalyst containing, on an amorphous support, at least one metal or metal compound having (having) a hydrodehydrogenation function. Generally speaking, the catalyst is used whose pore distribution is suitable for processing raw materials containing metals.

The hydrodehydrogenation function may be provided by at least one group VIII metal selected from the group consisting of nickel and / or cobalt, optionally in combination with at least one group VIB metal selected from the group consisting of molybdenum and / or tungsten . It is possible, for example, to use a catalyst containing from 0.5% to 10 wt.% Nickel and preferably from 1% to 5 wt.% Nickel (in the form of nickel oxide, NiO) and from 1% to 30 wt.% Molybdenum, preferably from 5 % to 20 wt.% molybdenum (in the form of molybdenum oxide, MoO ₃ ), on an amorphous inorganic substrate. The total amount of metal oxides of groups VIB and VIII is often from 5% to 40 wt.% And in general from 7% to 30 wt.%. The mass ratio, expressed as a Group VI metal oxide (or metals) to a Group VIII metal oxide (or metals), is typically from about 20 to about 1 and, as a rule, from about 10 to about 2.

The catalyst support will be selected, for example, from the group consisting of alumina, silica, aluminosilicates, magnesium oxide, clays and mixtures of at least two of these minerals. This substrate may also include other compounds, for example, oxides selected from the group consisting of boron oxide, zirconium oxide, titanium oxide and phosphoric anhydride. As a rule, an aluminum dioxide substrate and very often an aluminum dioxide substrate doped with phosphorus and, if necessary, boron are used. In this case, the concentration of phosphoric anhydride, P ₂ O ₅ , is usually less than about 20 wt.% And usually less than about 10 wt.%, And at least 0.001 wt.%. The concentration of boron trioxide, B ₂ O ₃ , as a rule, is from about 0% to about 10 wt.%. The alumina used is typically γ (gamma) or η (this) alumina. This catalyst is typically used in the form of an extrudate. The catalyst in step b) is preferably based on nickel and phosphorus doped molybdenum and on an alumina support. An HTS 458 catalyst sold by Axens may be used, for example.

Prior to introducing the deasphalted oil, the catalysts used in the method according to the present invention may be subjected to a sulfurization treatment to convert, at least partially, the metal groups to sulfides before they come into contact with the feed to be treated. This activating treatment by sulfurization is well known to specialists in this field of technology and can be carried out by a method already described in the literature, either in situ, i.e. inside the reactor, or ex situ.

The spent catalyst is often replaced with a fresh catalyst by withdrawing from the bottom of the reactor and introducing fresh or new catalyst at the top of the reactor, at regular intervals, for example by conventional or quasi-continuous addition. It is possible, for example, to introduce a fresh catalyst every day. The replacement level of the spent catalyst with a fresh catalyst can be, for example, from about 0.05 kg to about 10 kg per m ^{3 of} feedstock. This conclusion and this substitution are carried out using devices that provide continuous operation of this stage of hydroconversion. The assembly typically comprises a recirculation pump to maintain the fluidized bed catalyst by continuously recirculating at least a portion of the liquid removed from the top of the reactor and re-entering it at the bottom of the reactor. It is also possible to transport spent catalyst discharged from the reactor to a regeneration zone in which the carbon and sulfur that it contains are removed, and then introduce this regenerated catalyst back into the hydroconversion reactor in step b).

Operating conditions associated with catalytic activity provide possible degrees of conversion of the feed from 50% to 95%, preferably from 70% to 95%. The above conversion is defined as the mass fraction of the feed at the beginning of the reaction minus the mass fraction, the heavy fraction having a boiling point of more than 343 ° C, at the end of the reaction, this value being divided by the mass fraction of the feed at the beginning of the reaction.

The fluidized bed technique allows the processing of raw materials that are heavily contaminated with metals, sediments and heteroatoms without the problems of pressure loss or clogging problems that are known when using a fixed layer. Metals, such as nickel, vanadium, iron and arsenic, are largely removed from the feed by precipitation on the catalysts during the reaction. Removable (volatile) arsenic will be removed at the hydrotreatment stages using specific protective layers. Sediments present in shale oils are also removed by replacing the catalyst in a fluidized bed without disrupting hydroconversion reactions. These stages also provide removal, hydrodenitrogenation, of the main part of nitrogen, leaving only the majority of stable nitrogen compounds.

The hydroconversion in step b) makes it possible for the resulting output stream to contain no more than 3000 mass parts per million nitrogen, preferably not more than 2000 mass parts per million nitrogen.

Atmospheric distillation fractionation

The effluent obtained from the hydroconversion step b) is introduced at least partially, and preferably completely, into the fractionation zone from which the gaseous fraction, naphtha, gas oil fraction and a fraction heavier than the gas oil fraction are separated by atmospheric distillation.

The effluent obtained in stage b) is preferably fractionated by atmospheric distillation into a gaseous fraction having a boiling point of less than about 50 ° C, a naphtha boiling from about 50 ° C to about 150 ° C, a gas oil fraction boiling from about 150 ° C to about 370 ° C, and a fraction that is heavier than the gas oil fraction, and which typically boils at a temperature above 340 ° C, preferably at a temperature above 370 ° C.

Ligroin and diesel fractions are then separately introduced into the parts for hydroprocessing. A fraction heavier than the gas oil fraction is introduced into the unit to remove impurities in step a), where it is mixed into the feed.

The gaseous fraction contains gases (H ₂ , H ₂ S, NH ₃ , H ₂ O, CO ₂ , CO, C ₁ -C ₄ hydrocarbons, etc.). It can preferably be purified to recover hydrogen and to recycle it into the hydroconversion part in step b) or the hydrotreatment part in steps d) and e). After purification, C ₃ and C ₄ hydrocarbons can be used to form LPG (liquefied petroleum gas) products. Non-condensed gases (C ₁ -C ₂ ) are typically used as internal fuel for heating furnaces in hydroconversion and / or hydrotreatment reactors. C ₁ -C ₄ hydrocarbons isolated from the gaseous fraction can, if necessary, be used to carry out the step of removing contaminants a). The operating conditions for the removal of contaminants (pressure, temperature, solvent / feed ratio) will vary depending on the nature of the feed containing shale oil and will be established taking into account compatibility with the desired cleaning parameters.

Hydrotreating ligroin and gas oil fractions

The ligroin and gas oil fractions are then separately hydrotreated with a fixed layer [stages d) and e)]. Hydrotreating refers to hydrodesulfurization, hydrodenitrogenation and hydrodemetallization reactions. The task, depending on the working conditions, which are chosen more or less strict, is to obtain various fractions according to the technical conditions (sulfur content, maximum height of the non-soaking flame, cetane, aromatic content, etc.) or to obtain synthetic crude oil. Processing naphtha in one part for hydrotreatment and a fraction of gas oil in another part for hydrotreatment provides improved performance in terms of operating conditions, so as to ensure that each fraction meets the technical specifications with a maximum output and in one stage per fraction. Thus, fractionation after hydroprocessing is not necessary. The difference between the two parts for hydroprocessing is more based on differences in operating conditions than on the choice of catalyst.

The fixed-bed hydroprocessing portions preferably comprise upstream specific catalyst layers for the arsenic compounds (arsenic containing compounds) and silicon compounds that are optionally present in naphtha and / or diesel fractions. Compounds containing arsenic released from the fluidized bed (being, as a rule, relatively volatile) are captured by the protective layers, thus preventing the poisoning of catalysts located downstream and making it possible to obtain a fuel base that is very depleted in arsenic.

Protective layers that remove arsenic and silicon from fractions of naphtha or gas oil are well known to those skilled in the art. They contain, for example, an absorbent material containing nickel deposited on an appropriate substrate (silica, magnesium oxide or alumina), as described in FR 2617497, or else an absorbent material containing copper on a substrate, as described in FR 2762004. mention protective layers supplied by Axens: ACT 979, ACT 989, ACT 961, ACT 981.

The operating conditions in each hydroprocessing unit are adapted for the raw material to be processed. The operating conditions for hydrotreatment of naphtha are generally milder than the operating conditions for hydrotreating a gas oil fraction.

At the hydrotreatment stage, ligroin [stage d)] is usually operated at an absolute pressure of 4 to 15 MPa, often 10 to 13 MPa. The temperature during this step d) is usually from 280 ° C to 380 ° C, often from 300 ° C to 350 ° C. This temperature is usually set in accordance with the desired level of hydrodesulfurization. The hourly average feed rate (HSV) is typically in the range of 0.1 h ^-1 to 5 h ^-1 , preferably 0.5 h ^-1 to 1 h ^-1 . The amount of hydrogen mixed with the feed is typically from 100 to 5000 normal cubic meters (Nm ³ ) per cubic meter (m ³ ) of liquid feed, and typically from 200 to 1000 Nm ³ / m ³ , and preferably from 300 to 500 Nm ³ / m ³ . It is useful to work in the presence of hydrogen sulfide (for sulfurization of the catalyst), and the partial pressure of hydrogen sulfide is usually from 0.002 times to 0.1 times, and preferably from 0.005 times to 0.05 times the total pressure.

At the hydroprocessing stage, the gas oil fractions [stage e)] usually operate at an absolute pressure of from 7 to 20 MPa, often from 10 to 15 MPa. The temperature during this step e) is usually from 320 ° C to 450 ° C, often from 340 ° C to 400 ° C. This temperature is usually set in accordance with the desired level of hydrodesulfurization. Mass hourly consumption is from 0.1 to 1 h ^-1 . The hourly average feed rate (HSV) is typically in the range from 0.2 h ^-1 to 1 h ^-1 and preferably from 0.3 h ^-1 to 0.8 h ^-1 . The amount of hydrogen mixed with the feed is typically from 100 to 5000 normal cubic meters (Nm ³ ) per cubic meter (m ³ ) of liquid feed, and typically from 200 to 1000 Nm ³ / m ³ , and preferably from 300 to 500 Nm ³ / m ³ . It is useful to work in the presence of hydrogen sulfide (for sulfurization of the catalyst), and the partial pressure of hydrogen sulfide is usually from 0.002 times to 0.1 times, and preferably from 0.005 times to 0.05 times the total pressure.

In parts for hydroprocessing, an ideal catalyst should have a high hydrogenating ability so as to produce thoroughly refined products and achieve a significant reduction in sulfur and nitrogen. In a preferred embodiment of the present invention, the hydroprocessing parts operate at a relatively low temperature, which facilitates careful hydrogenation and limits coking of the catalyst. The use of one catalyst or two or more different catalysts, simultaneously or sequentially, in parts for hydroprocessing will not be beyond the scope of the present invention. Hydrotreating in stages d) and e) is usually carried out industrially in one or more liquid downstream reactors.

In two parts, the same type of catalyst is used for the hydroprocessing [stages d) and e)]; the catalysts in each part may be the same or different. At least one fixed bed of a conventional hydrotreating catalyst is used, comprising, on an amorphous substrate, at least one metal or metal compound having a hydrodehydrogenation function.

The hydrodehydrogenation function may be provided by at least one group VIII metal selected from the group consisting of nickel and / or cobalt, optionally in combination with at least one group VIB metal selected from the group consisting of molybdenum and / or tungsten . It is possible, for example, to use a catalyst containing from 0.5% to 10 wt.% Nickel and preferably from 1% to 5 wt.% Nickel (in the form of nickel oxide, NiO) and from 1% to 30 wt.% Molybdenum, preferably from 5 % to 20 wt.% molybdenum (in the form of molybdenum oxide, MoO ₃ ), on an amorphous inorganic substrate. The total amount of metal oxides of groups VI B and VIII is often from 5% to 40 wt.% And in general from 7% to 30 wt.%. The mass ratio, expressed as a Group VI metal oxide (or metals) to a Group VIII metal oxide (or metals), is typically from about 20 to about 1 and, as a rule, from about 10 to about 2.

The catalyst support will be selected, for example, from the group consisting of alumina, silica, aluminosilicates, magnesium oxide, clays and mixtures of at least two of these minerals. This substrate may also include other compounds, for example, oxides selected from the group consisting of boron oxide, zirconium oxide, titanium oxide and phosphoric anhydride. As a rule, an aluminum dioxide substrate and very often an aluminum dioxide substrate doped with phosphorus and, if necessary, boron are used. In this case, the concentration of phosphoric anhydride, P ₂ O ₅ , is usually less than about 20 wt.% And usually less than about 10 wt.%, And at least 0.001 wt.%. The concentration of boron trioxide, B ₂ O ₃ , as a rule, is from about 0% to about 10 wt.%. The alumina used is typically γ (gamma) or η (this) alumina. This catalyst is typically used in the form of extrudates.

Prior to introducing the feed, the catalysts used in the process of the present invention may be subjected to a sulfurization treatment to convert, at least in part, the metal groups to sulfides before they come into contact with the feed to be treated. This activating treatment by sulfurization is well known to specialists in this field of technology and can be carried out by a method already described in the literature, either in situ, i.e. inside the reactor, or ex situ.

Hydrotreating in step d) of the ligroin fraction results in a fraction containing not more than 1 parts by weight per million nitrogen, preferably not more than 0.5 parts by weight per million nitrogen, and not more than 5 parts by weight per million sulfur, preferably not more than 0.5 parts by weight parts per million sulfur.

The hydrotreatment in step e) of the gas oil fraction results in a fraction containing not more than 100 parts by mass per million nitrogen, and not more than 20 parts by mass of nitrogen, and not more than 50 parts by mass of sulfur, preferably not more than 10 parts by mass parts per million sulfur.

Catalytic cracking

Finally, in one embodiment, the method of the present invention may comprise a catalytic cracking step [step g)] in which at least a portion, preferably an entire volume, of a fraction heavier than the gas oil obtained in step c) is introduced into the portion for conventional catalytic cracking, in which the specified fraction, heavier than gas oil, is processed in the usual way, under conditions well known to the person skilled in the art, to obtain a second gaseous fraction, a second gasoline fraction, a second a gas oil fraction; and a second fraction heavier than a gas oil referred to as a “suspension”. The second gas oil fraction will, for example, be at least partially introduced into the fuel tanks (pools) and / or recycled, at least partially, or even completely, to the gas oil hydrotreatment step e). The second fraction, heavier than gas oil, will, for example, be at least partially or even completely introduced into the heavy fuel oil tank (pool) and / or recycled, at least partially, or even completely, to the catalytic cracking step g ) At least a portion of the second fraction heavier than the gas oil obtained at the end of step g) is recycled to the contaminant removal step a). In the context of the present invention, the term “conventional catalytic cracking” encompasses cracking methods that comprise at least one stage of catalyst regeneration by partial combustion, and methods that comprise at least one stage of catalyst regeneration by complete combustion, and / or methods comprising at least one stage of partial combustion, and at least one stage of complete combustion.

For example, a general description of catalytic cracking (the first industrial use of which occurred in 1936 (the Houdry process) or in 1942 when using a catalyst in a fluidized bed) can be found in Ullmans Encyclopedia of Industrial Chemistry Volume A 18, 1991, pages 61-64. It is common to use standard catalysts containing a matrix, optionally an additive and at least one zeolite. The amount of zeolite varies, but usually ranges from about 3% to about 60 wt.%, Often from about 6% to about 50 wt.%, And from about 10% to 45 wt.% Are usually used. Zeolite is usually dispersed in a matrix. The amount of additive is usually from about 0% to about 30 wt.%. The amount of matrix is the residue necessary to achieve 100 wt.%. The additive is typically selected from the group consisting of metal oxides from group IIA of the periodic table of elements, such as magnesium oxide or calcium oxide, rare earth oxides and metal titanates from group IIA. The matrix is typically silica, alumina, aluminosilicate, magnesium silicate, clay, or a mixture of two or more of these products. The most commonly used zeolite is zeolite Y. Cracking is carried out in a substantially vertical reactor, in either upflow or downflow mode. The choice of catalyst and operating conditions depends on the target products, depending on the raw materials being processed, as described, for example, in M. Marcilly article, pages 990-991, published in Institut Francais du Petrole, Nov. - Dec. 1975, pages 969-1006. Usually operate at temperatures from 450 ° C to 600 ° C with a residence time of less than 1 minute, often from about 0.1 to about 50 seconds.

The catalytic cracking step g) may also be a catalytic cracking stage with a fluidized bed, for example, according to the method designated R2R. This step can be carried out in the usual manner, as is known to those skilled in the art, under suitable cracking conditions to produce low molecular weight hydrocarbon products. A description of the mode and catalysts that can be used in the context of fluidized bed cracking at this stage g) are described, for example, in patent documents US-A-5286690, US-A-5324696 and EP-A-699224.

The catalytic cracking reactor with a fluidized bed can operate in upstream mode or in a downward flow mode. Although this is not a preferred embodiment of the present invention, in a similar manner, it is possible to consider the implementation of catalytic cracking in a moving bed reactor. Particularly preferred catalytic cracking catalysts are catalysts containing at least one zeolite, usually in admixture with a suitable matrix, such as, for example, alumina, silica or aluminosilicate.

According to the penultimate object, the present invention relates to the production of synthetic petroleum feedstock by the method according to one of the preceding objects.

According to a last aspect, the present invention relates to a plant for treating shale oil using a method according to one of the preceding objects.

Such an installation contains:

- a part for removing contaminants of the shale oil to be treated,

- part for hydroconversion in the presence of hydrogen, containing a fluidized bed reactor operating in a gaseous and liquid ascending mode and containing at least one hydroconversion catalyst on a substrate,

- zone for fractionation using atmospheric distillation,

- part for hydroprocessing in the presence of hydrogen, containing a fixed-bed reactor containing at least one hydroprocessing catalyst,

- another part for hydroprocessing in the presence of hydrogen, containing at least one fixed-bed reactor containing at least one hydroprocessing catalyst,

these elements are located to implement the method according to the present invention.

Accordingly, for example:

- the part for removing contaminants is connected to the part for hydroconversion to feed this part for hydroconversion with processed shale oil leaving the part for removing contaminants,

- the hydroconversion part is connected to the fractionation zone in order to feed this fractionation zone by the effluent from the hydroconversion part,

- one pipe (line) connects the fractionation zone to one of two parts for hydroprocessing, the other pipe (line) connects the fractionation zone to one of the two parts for hydroprocessing.

A catalytic cracking part may be provided, with another pipe (line) connecting the fractionation zone to this catalytic cracking part.

The installation may further comprise one or more recirculation pipes for introducing various fractions into the part for removing impurities or into the part for catalytic cracking.

Figure 1 shows in diagrammatic form the method according to the present invention. Figure 2 in the form of a diagram shows a variant of the method, which includes the stage of catalytic cracking.

According to Figure 1, raw materials containing shale oil (1) to be processed, is introduced into the part to remove impurities (3) using line (2). This step (3) is a deasphalting carried out using a solvent (not shown), during which deasphalted oil (4) and a residue (5) are produced. The remainder (5), through line (6), can be used as fuel or can feed the gasification unit for the production of hydrogen and energy.

Deasphalted oil (4) is introduced via line (7) into the fluidized bed hydroconversion section (8) in the presence of hydrogen (9), moreover, hydrogen (9) is introduced via line (10). The stream leaving the fluidized bed hydroconversion section (8) is introduced via line (11) into the atmospheric distillation column (12), at the end of which a gaseous fraction (13), naphtha (14), gas oil fraction (15) and fraction (16), heavier than the gas oil fraction. The gaseous fraction (13) containing hydrogen can be purified (not shown) to recycle hydrogen and reintroduce it into the fluidized bed hydroconversion section (8) along line (10) and / or the hydroprocessing section (17) and / or (18) along lines (19) and (20). Ligroin (14) is introduced into the hydrotreatment unit with a fixed layer (17), at the end of which ligroin (21), depleted in impurities, is isolated. The gas oil fraction (15) is introduced into the hydrotreatment section with a fixed layer (18), at the end of which the gas oil fraction (22) is depleted of impurities. Two parts for hydroprocessing (17) and (18) are fed with hydrogen along lines (23) and (24). Fraction (16), heavier than the gas oil fraction, is recycled to the deasphalting unit (3) along line (25).

In Fig.2, the stages of liquid / liquid extraction, hydroconversion, separation and hydrotreatment (and symbols) are identical to those in Fig.1. Fraction (16), heavier than the gas oil fraction that occurs at the stage of atmospheric distillation, can be sent to the catalytic cracking unit (26) along line (27). The stream leaving this part (26) is directed via line (28) to the fractionation part (29), preferably by atmospheric distillation, from which fuel or middle distillate fractions containing at least one second gasoline fraction (30) come out a second fraction of gas oil (31) and a second fraction (32), heavier than gas oil, also called "suspension". The second gas oil fraction (31) is introduced at least partially into the fuel tanks (pools) and / or recycled at least partially, or even completely, to the gas oil hydrotreatment step e) (18) via line (33). The second fraction (32), heavier than gas oil (″ suspension ″), for example, at least partially, or even completely, is introduced into the tank for heavier fuel oil (pool) and / or recycled, at least partially or even completely, to the catalytic cracking stage (26) along line (34). The second fraction (32), heavier than gas oil, is, if necessary, introduced, partially or completely, into the deasphalting unit (3) via line (35).

Example

Process shale oil, which has the characteristics shown in Table 1.

Table 1 Characteristics of oil based on shale oil Density 15/4 - 0.948 Hydrogen wt.% 10.9 Sulfur wt.% 1.9 Nitrogen wt.% 0.9 Oxygen wt.% 2.4 Asphaltenes wt.% 2.0 Conradson carbon residue wt.% 3.1 Metals Ppm 195

Shale oil, from which C ₅ hydrocarbons were separated, is subjected to primary atmospheric distillation, from which volatile products, gas oil components, kerosene and naphtha are extracted and processed in the cleaning chain according to their properties. Atmospheric distillation of shale oil also leads to fuel oil, which contains most of the compounds having a boiling point of more than 350 ° C. Fuel oil, in the context of the present invention, is 40% by weight of the feed. This feed is subjected to propane deasphalting at a solvent / feed ratio of 5/1, at a temperature of 100 ° C and at 4 MPa. So get deasphalted oil and residue.

Deasphalted oil is treated in a fluidized bed reactor containing Axens industrial catalyst HTS458. The operating conditions are as follows:

- Temperature in the reactor: 425 ° C

- Pressure: 195 bar (19.5 MPa)

- The ratio of hydrogen / raw materials: 400 Nm ³ / m ³

- Total HSV: 0.6 h ^-1

Liquid products obtained from the reactor are fractionated by atmospheric distillation to obtain ligroin (C5 + - 150 ° C), a gas oil fraction (150-370 ° C) and a residual fraction of 370 ° C +, which is a heavier fraction than gas oil.

Ligroin is subjected to fixed-bed hydroprocessing using a NiMo alumina catalyst. The operating conditions are as follows:

- Temperature in the reactor: 320 ° C

- Pressure: 50 bar (5 MPa)

- The ratio of hydrogen / raw materials: 400 Nm ³ / m ³

- Total HSV: 1 h ^-1

The gas oil fraction is subjected to fixed-bed hydroprocessing using a NiMo catalyst on alumina. The operating conditions are as follows:

- Temperature in the reactor: 350 ° C

- Pressure: 120 bar (12 MPa)

- The ratio of hydrogen / raw materials: 400 Nm ³ / m ³

- Total HSV: 0.6 h ^-1

The heavier fraction than gas oil is then subjected to catalytic cracking using a catalyst containing 20 wt.% Zeolite Y and 80 wt.% Aluminosilicate matrix. This feedstock, preheated to 135 ° C, is introduced at the bottom of a vertical reactor with a catalyst from a regenerator, the catalyst being regenerated under hot conditions. The inlet temperature of the catalyst in the reactor is 720 ° C. The ratio of the catalyst flow rate to the feed flow rate is 6.0. The thermal contribution of the catalyst at 720 ° C promotes the evaporation of the feed and the cracking reaction, and both are endothermic. The average residence time of the catalyst in the reaction zone is about 3 seconds. The working pressure is 1.8 absolute bar. The temperature of the catalyst, measured at the end of a step-up controlled (vertical) fluidized bed reactor, is 525 ° C. Cracked hydrocarbons and the catalyst are separated by cyclones located in the distillation zone (evaporation column), in which the catalyst is distilled off. The catalyst, which is charged with coke during the reaction and then distilled off in the distillation zone, is then introduced into the regenerator. The coke solids content (delta coke) at the start of the generator is 0.85%. This coke is burned by air introduced into the regenerator. Combustion, which is highly exothermic, raises the temperature of a solid from 525 ° C to 720 ° C. The hot regenerated catalyst exits the reactor and is introduced again at the bottom of the reactor.

Hydrocarbons separated from the catalyst exit the stripping zone. They are sent to the main fractional distillation column, at the top of which gases and gasoline fractions exit, and then, at the bottom of the column, to increase the boiling point, the LCO and HCO fractions and suspension (370 ° C +) exit.

Table 2 summarizes the properties of the various feedstocks at each stage, as well as the yields obtained at various sites, and the total yield. Therefore, it is observed that based on 100% by weight of shale oil, 86.2% by weight of products (LPG, naphtha, middle distillates) are obtained that meet Euro V specifications.

table 2 Cleaning unit Atmospheric distillation Solvent deasphalting Solvent de-asphalting H-Oil _DC Fcc Raw materials Shale Oil C5 + 360 ° C + shale oil 360 ° C + shale oil Deasphalted oil H-Oil _DC bottom sediment Product 360 ° C + shale oil Deasphalted oil The remainder H-Oil _DC bottom sediment Ex-fcc products Yield based on raw materials from shale oil wt.% 40.0 28.0 12.0 5.9 Product properties Density (d15 / 4) - 1.035 0.980 1.191 0.905 Sulfur wt.% 1.5 1.3 2.0 0.06 Total nitrogen wt.% 1.1 0.7 1.8 0.15 Output for each node LPG wt.% 2.0 10.0 Lagroin wt.% 19.0 55.0 Middle distillate wt.% 56.0 14.0 Bottom sediment wt.% 21.0 5.0 wt.% Shale oil yield wt.% LPG wt.% 0.6 0.6 Lagroin wt.% 5.3 3.2 Middle distillate wt.% 15.7 0.8 Bottom sediment wt.% 5.9 0.3 total (LPG + lagroin + middle distillate) / raw shale oil 60.0 21.6 4.6 total (LPG + lagroin + middle distillate) / raw shale oil 86.2

Claims (25)

1. The method of conversion of shale oil or a mixture of shale oils having a nitrogen content of at least 0.1 wt. %, characterized in that it contains the following stages:
a) the raw material is subjected to the removal of contaminants to obtain a residue and an oil purified from contaminants,
b) an oil purified from contaminants is introduced into the gyroconversion part in the presence of hydrogen, said part comprising at least one fluidized bed reactor operating in a gaseous and liquid ascending mode and containing at least one hydroconversion catalyst on a substrate,
c) the effluent obtained in step b) is introduced at least partially into the fractionation zone, from which, through atmospheric distillation, a gaseous fraction, a ligroin fraction, a gas oil fraction and a heavier fraction than gas oil are released,
d) said ligroin fraction is processed at least partially in another hydrotreatment portion in the presence of hydrogen, said portion comprising at least one fixed bed reactor comprising at least one hydroprocessing catalyst, and
e) said gas oil fraction is processed at least partially in the hydrotreatment portion in the presence of hydrogen, said portion comprising at least one fixed bed reactor comprising at least one hydrotreatment catalyst. 2. The method according to claim 1, where the shale oil or a mixture of shale oils have a nitrogen content of at least 1 wt. % 3. The method according to p. 1, where the shale oil or a mixture of shale oils have a nitrogen content of at least 2 wt. % 4. The method of claim 1, wherein in step c), the effluent obtained in step b) is introduced completely into the fractionation zone. 5. The method according to p. 1, where in stage d) the specified fraction of ligroin is processed completely in another part for hydroprocessing in the presence of hydrogen. 6. The method according to p. 1, where in stage e) the specified fraction of gas oil is processed completely in part for hydroprocessing in the presence of hydrogen. 7. The method according to p. 1, characterized in that it further comprises a step f), in which at least a fraction of a fraction heavier than gas oil is introduced into step a) for purification from contamination. 8. The method of claim 1, wherein the effluent obtained in step b) is fractionated by atmospheric distillation into a gaseous fraction having a boiling point of less than 50 ° C., a naphtha fraction boiling at a temperature of from 50 ° C. to 150 ° C. a gas oil fraction boiling at a temperature of from 150 ° C to 370 ° C; and a fraction that is heavier than a gas oil fraction and which boils, as a rule, at a temperature above 340 ° C. 9. The method according to p. 1, in which the removal of contaminants in stage a) is carried out using a solvent selected from the group consisting of propane, n-butane, isobutane, n-pentane, cyclopentane, 2-methylbutane, 2,2-dimethylpropane and mixtures thereof in any proportions. 10. The method according to p. 1, in which the stage of removing contaminants a) is carried out at a ratio of solvent / raw material from 3/1 to 8/1, at a temperature of 60 ° C to 250 ° C and at a pressure of 4 MPa to 5 MPa. 11. The method according to p. 1, in which the stage of removing contaminants a) is carried out at a solvent / raw material ratio of 4/1 to 6/1, at a temperature of 60 ° C to 200 ° C and at a pressure of 4 MPa to 5 MPa. 12. The method according to claim 1, in which the part for hydroprocessing with a fixed layer in stage d) and / or e) contains, upstream of the catalytic layers of the hydroprocessing, at least one specific protective layer for arsenic compounds and silicon compounds. 13. The method according to claim 1, wherein at least a portion of the fraction heavier than gas oil is introduced into the catalytic cracking portion indicated by step g), in which it is processed under conditions that produce a second gaseous fraction, a second gasoline fraction , the second fraction of gas oil and the second fraction, heavier than gas oil. 14. The method of claim 13, wherein at least a portion of the second fraction heavier than the gas oil obtained at the end of step g) is recycled to the beginning of said step g). 15. The method of claim 13, wherein at least a portion of the second fraction heavier than the gas oil obtained at the end of step g) is recycled to the gas oil hydrotreatment step e). 16. The method of claim 13, wherein at least a portion of the second fraction heavier than the gas oil obtained at the end of step g) is recycled to the decontamination step a). 17. The method according to p. 1, in which the hydroconversion stage b) is carried out at a temperature of from 300 ° C to 550 ° C, at a total pressure of 2 to 35 MPa, with a mass hourly flow rate ((feed time / hour) / catalyst time) equal to from 0.2 to 1.5 h ^-1 , and with a hydrogen / feed ratio of from 50 to 5000 Nm ³ / m ³ . 18. The method according to p. 1, in which the hydroconversion stage b) is carried out at a temperature of from 400 ° C to 450 ° C, at a total pressure of 10 to 20 MPa, at a mass hourly flow rate ((feed time / hour) / catalyst time) equal to from 0.2 to 1.5 h ^-1 , and with a hydrogen / feed ratio of from 100 to 1000 Nm ³ / m ³ . 19. The method according to p. 1, in which the stage of hydroprocessing of the ligroin fraction d) is carried out at a temperature of from 280 ° C to 380 ° C, at a total pressure of 4 to 15 MPa, with a mass hourly flow rate ((feed time / hour) / time catalyst), equal to from 0.1 to 5 h ^-1 , and with a hydrogen / feed ratio of from 100 to 5000 Nm ³ / m ³ . 20. The method according to p. 1, in which the stage of hydroprocessing of the ligroin fraction d) is carried out at a temperature of from 300 ° C to 350 ° C, at a total pressure of 10 to 13 MPa, with a mass hourly flow rate ((feed time / hour) / time catalyst), equal to from 0.5 to 1 h ^-1 , and with a hydrogen / feed ratio of from 100 to 1000 Nm ³ / m ³ . 21. The method according to p. 1, in which the stage of hydroprocessing of the gas oil fraction e) is carried out at a temperature of from 320 ° C to 450 ° C, at a total pressure of 7 to 20 MPa, with a mass hourly flow rate ((feed time / hour) / time catalyst), equal to from 0.1 to 1 h ^-1 , and with a hydrogen / feed ratio of from 100 to 5000 Nm ³ / m ³ . 22. The method according to p. 1, in which the stage of hydroprocessing of the gas oil fraction e) is carried out at a temperature of from 340 ° C to 400 ° C, at a total pressure of 10 to 15 MPa, with a mass hourly flow rate ((feed time / hour) / time catalyst), equal to from 0.3 to 0.8 h ^-1 , and with a hydrogen / feed ratio of 200 to 1000 Nm ³ / m ³ . 23. The method according to claim 1, wherein the catalysts in the hydroconversion stage b) and the hydroprocessing stages d) and e) are independently selected from the group of catalysts containing a metal of group VIII selected from the group consisting of Ni and / or Co, optionally a metal group VIB selected from the group consisting of Mo and / or W on an amorphous substrate selected from the group consisting of alumina, silica, aluminosilicates, magnesium oxide, clays, and mixtures thereof. 24. The method according to any one of the preceding paragraphs, in which shale oil or a mixture of shale oils is provided from hydrocarbon raw materials selected from the group consisting of oils derived from coal, oils derived from heavy resins and tar sand, vacuum distillates and direct distillation residues , vacuum distillates and unconverted residues obtained from the processing of fuel oil, oils deasphalted with solvents, light cyclic oils, heavy cyclic oils, gas oil fractions originating from of atalytic cracking and having, as a rule, a boiling range of a fraction from 150 ° C to 650 ° C, aromatic extracts obtained in the production of lubricating oils, pyrolytic oils of wood residues, such as wood waste, crude oil derived from biomass ("bio-raw materials" ), vegetable oils and animal fats, or mixtures of such raw materials. 25. Installation for processing shale oil by the method according to any one of paragraphs. 1-24, containing:
- a part for removing contaminants of the shale oil to be treated,
- part for hydroconversion in the presence of hydrogen, containing a fluidized bed reactor operating in a gaseous and liquid ascending mode and containing at least one hydroconversion catalyst on a substrate,
- zone for fractionation using atmospheric distillation,
- part for hydroprocessing in the presence of hydrogen, containing a fixed-bed reactor containing at least one hydroprocessing catalyst,
- another part for hydroprocessing in the presence of hydrogen, containing at least one fixed-bed reactor containing at least one hydroprocessing catalyst.

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