RU2360944C2 - Complex method of converting coal containing raw material into liquid products - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: invention refers to complex method of converting coal containing raw material into liquid products by means of combined implementation of at least following seven process blocks: liquation of coal (CL), instantaneous evaporation or rectification of product produced from liquation (IE), extraction with dissolvent for removal of non-combustible substances (ED), rectification for separation of dissolvent (SD), conversion with hydrogenation with catalyst in suspension phase (CH), rectification or instantaneous evaporation of product produced with conversion with hydrogenation (R), and de-asphalting with solvent; the method is characterised with following: it consists of phases - directing raw material containing coal to one or more, than one, stage (CL) of direct liquation of coal at presence of suitable catalyst of hydrogenation in disperse phase, and also at presence of hydrogen or hydrogen and H₂S, - directing flow containing product obtained from reaction of coal liquation to one or more, than one, stage (IE) of instantaneous evaporation or rectification producing gaseous flow and liquid flow,- directing liquid flow to stage (ED) of extraction with dissolvent, which results in producing non-soluble flow consisting of mineral substance present in raw material and of not-reacted coal and liquid flow consisting of produced liquefied coal and applied dissolvent, - directing liquid flow consisting of liquefied coal and applied dissolvent to one or more stages of rectification to separate in essence dissolvent contained in liquid flow, which is returned to stage (ED) of extraction with dissolvent; - mixing liquid flow in essence consisting of liquefied coal and at least part of flow containing pyrobitumens produced in block of de-asphalting with suitable catalyst in disperse phase and directing obtained mixture to reactor of hydro-processing (CH) supplying hydrogen or mixture of hydrogen and H₂S into it, - not necessary directing flow containing product of reaction of hydro-processing and catalyst in disperse phase to preliminary stage of separation, performed at high pressure with production of light and heavy fractions , - directing flow containing product of reaction of hydro-processing and catalyst in disperse phase or heavy fraction produced by means of stage of separation at high pressure to one or more, than one, stage (R) of rectification or instantaneous evaporation, which results in separation of different fractions obtained from reaction of hydro-processing, - directing at least part of residue after rectification (resin) or liquid leaving block of instantaneous evaporation containing catalyst in disperse phase rich with sulphides of metals produced by means of de-metallisation of raw material and, possibly, coke into zone of (D) de-asphalting at presence of solvents, into which, possibly, there is supplied at least one fraction of liquid flow in essence consisting liquefied coal obtaining two flows: one consisting of de-asphalted oil (DAO), and another - containing pyrobitumen.

EFFECT: high degree of raw material conversion obtaining products with low contents of resin and other impurities.

50 cl, 3 ex, 3 tbl, 1 dwg

Description

The present invention relates to a comprehensive method for the conversion of coal-containing raw materials to liquid products.

It is known that direct liquefaction of coal is based on hydrogenation treatment, which leads to an increase in the hydrogen / carbon ratio from 0.7-0.8 to values above unity and typical for hydrocarbon mixtures of petroleum origin.

This is a partial destruction of the organic structure of coal under hydrogenation conditions. Together with liquid products, gases and solids are also formed in quantities that vary depending on the processed raw materials, working conditions and type of process.

Liquefaction is usually based on a substantially thermal reaction that causes the formation of radicals that are stabilized by hydrogen having the function of preventing a decrease in their quality to produce much less chemically active molecules, and catalytic hydrogenation, which reduces the complexity of the molecules by cleaving the bonds between different carbon atoms and other carbon atoms, oxygen, nitrogen and sulfur.

These two reactions can be carried out in one stage or in two separate stages.

However, the result is the destruction of more complex hydrocarbon structures, accompanied by the reduction, or, as appropriate, the removal of oxygen, nitrogen and sulfur in the form of water, ammonia and hydrogen sulfide.

The reactions are carried out in the presence of a solvent, usually obtained in the method itself. The solvent plays a significant role in the conversion, as it is able to extract hydrogen rich products and dissolve complex molecules that are formed due to the heating effect, and is also able to promote the reaction with hydrogen as a transferor and donor. Therefore, an ideal solvent should have a high dissolving ability (and therefore consist of a highly aromatic structure with respect to similarity to the type of solute) and good characteristics as a hydrogen donor (and therefore should be easily hydrogenated and also give hydrogen easily to coal) .

From liquefaction processes, products can be obtained that vary from refined coal, still solid at room temperature, low in sulfur and ash, to light liquid products such as gasoline. In the first case, there are higher energy characteristics and mass yields; as the hydrogenation rigidity increases, when the hydrocracking reactions become more significant, the quality of the liquid product increases, but the yields decrease.

The approaches so far followed when liquefying coal to medium / light products can be comprehensively and schematically represented by the following process areas:

- liquefaction in very harsh conditions in one stage;

- liquefaction with several stages having different degrees of rigidity.

In the first case, thermal and catalytic reactions proceed in one reactor, under conditions that are compromise between different optimal conditions for two reactions: they usually carry out hard hydrocracking, obtaining products that can be distilled with great advantage in the careful and difficult separation between liquids and unreacted solid substances that can leak by flash evaporation.

However, one of the drawbacks is the production of a large amount of gas, an undesirable product, with a significant, as a result, hydrogen consumption.

Using a multi-stage scheme, it is possible to work under optimal conditions for individual reactors, thermal and catalytic (in particular, the first stage of liquefaction can be carried out with low stiffness, converting coal into a liquid extract, with low gas production due to the low category of hydrocracking reactions); but since most products cannot be distilled, it is necessary to resort to a more complex separation of the solid / liquid, vacuum distillation, such as anti-solvent treatment or filtration.

Finally, after separation of the solid and the liquid, the extract is subjected to a subsequent hydrocracking step under controlled catalytic conditions to facilitate products.

The full advantage is due to the better use of hydrogen with a low total flow rate and higher flexibility of the method, which leads to a greater choice in the spectrum of products.

Regardless of whether coal liquefaction is performed in one or more than one stage, liquids obtained from coal must be intensively recycled using special processing devices (hydrocracking, performed using traditional technologies), since they are substantially aromatic and are rich in nitrogen , sulfur and have a high density to form distillation products having industrial characteristics.

It has now been found that by exposing these liquids obtained by liquefying coal to some additional conversion processes by hydrogenation treatment already used to convert heavy crude oil or distillation residues, the conversion yields for DAM distillation products (deasphalted oil) can be maximized.

Hydrogenation processes for the conversion of heavy crude oil or distillation residues consist in processing the feed in the presence of hydrogen and suitable catalysts.

Currently, in the market hydrogenation conversion technologies, fixed-bed or fluidized-bed reactors and adopted catalysts consisting of one or more transition metals (Mo, W, Ni, Co, etc.) supported on silicon dioxide / are used. alumina (or equivalent material).

Fixed-bed technologies have significant problems in processing especially heavy raw materials having a high percentage of heteroatoms, metals and asphaltenes, since these contaminants cause a rapid loss of catalyst activity.

Fluidized bed technologies were developed and put into production for processing this raw material, and they provide interesting characteristics, but are complex and expensive.

Hydroprocessing technologies that work with dispersed phase catalysts can be an attractive solution to address the disadvantages that arise when using fixed or fluidized bed technologies. In fact, the suspension processes combine the advantages of wide flexibility with respect to raw materials with high characteristics in terms of conversion and quality improvement, confirming that they are, at least in principle, easier from a technological point of view.

Suspension technologies are characterized by the presence of catalyst particles with very small average sizes that effectively disperse in the medium; for this reason, hydrogenation processes are easier and more efficient at all points in the reactor. Coke formation is significantly reduced and the quality improvement of raw materials is high.

The catalyst can be introduced in the form of a powder with sufficiently small particle sizes or in the form of an oil-soluble precursor. In the latter case, the active form of the catalyst (usually metal sulfide) is formed in situ by thermal decomposition of the compound used during the reaction itself or after suitable pretreatment.

The metal included in the dispersed catalyst is usually one or more than one transition metal (preferably Mo, W, Ni, Co or Ru). Molybdenum and tungsten have much more satisfactory characteristics than nickel, cobalt or ruthenium, and even better than those for vanadium and iron (N. Panariti et. Al., App. Catal. A: Gen. 2000, 204, 203) .

Although the use of dispersed catalysts solves most of the problems listed for the technologies described above, it also has drawbacks, mainly related to the life of the catalyst itself and the quality of the products obtained.

In fact, the conditions of use of these catalysts (type of precursors, concentration, etc.) are of great importance both from an economic point of view and in terms of environmental impact.

The catalyst can be used in a low concentration (several hundred parts per million (ppm) in a “one-time” configuration, but in this case, improving the quality of the reaction products is usually not sufficient (A. Delbianco et. Al., Chemtech, November 1995 , 35) .With work with extremely active catalysts (for example, molybdenum) and with higher catalyst concentrations (thousands of ppm of metal), the quality of the product obtained becomes much better, but the catalyst must be reused.

The catalyst leaving the reactor can be removed by separating the product obtained after hydrotreatment (preferably from the bottom of the distillation column located downstream of the reactor) by conventional methods, such as decantation, centrifugation or filtration (US patent No. 3240718; US patent No. 4762812). Part of the catalyst can be returned to the hydrogenation process without any additional processing. The catalyst recovered using known hydrotreating techniques, however, usually has a reduced activity with respect to the fresh catalyst, so that a suitable regeneration step is necessary to restore the catalytic activity and return at least a portion of said catalyst to the hydrotreatment reactor. Moreover, these catalyst recovery operations are expensive and also extremely complex from a technological point of view.

All the hydrogenation conversion methods described above make it possible to achieve more or less high degrees of conversion, depending on the raw materials used and the type of technology, but they form an unconverted residue at the stability limit, which we will call the resin (tar), which, from case to case can make up from 15 to 85% of the feedstock. This product is used to produce fuel oil, bitumen, or it can be used as a raw material in gasification processes.

To increase the overall degree of conversion of the cracking processes of the residues, a scheme has been proposed that provides for the return of more or less significant quantities of resin to the cracking unit. In the case of hydrogenation conversion processes with dispersed catalysts in the suspension phase, the recovery of the resin also allows the recovery of the catalyst to the extent described by the same applicants in patent application IT-95A001095; a method that allows the recoverable catalyst to be returned to the hydrotreatment reactor without the need for an additional regeneration step, while at the same time obtaining a good quality product without producing a residue (zero residue processing).

This method includes the following steps:

- mixing the heavy crude oil or the residue after distillation with a suitable hydrogenation catalyst and directing the resulting mixture to the hydroprocessing reactor, supplying it with hydrogen or a mixture of hydrogen and H ₂ S;

- the direction of the stream containing the reaction products of the hydroprocessing and the catalyst in the dispersed phase, in the distillation zone, in which the most volatile fractions (ligroin and gas oil) are separated;

- the direction of high-boiling fractions obtained at the stage of distillation, to the stage of deasphalting and the subsequent formation of two streams, one consisting of deasphalted oil (DAM), and the other consisting of asphaltenes, a catalyst in the dispersed phase and possibly coke and enriched with metals from the source raw materials;

- the return of at least 60%, preferably at least 80% of the stream consisting of asphaltenes, a catalyst in the dispersed phase and possibly coke and enriched with metals, in the hydrotreatment zone.

Subsequently, it was found, as described in patent application IT-M12001A-001438, that in the case of improving the quality of heavy crude oil or bitumen from oil sands to complex hydrocarbon mixtures intended for use as a raw material for further conversion processes to distillation products, it may be convenient the use of other configurations of the method as described above.

The method for the conversion of heavy raw materials described in patent application IT-M12001A-001438 by sharing three processing units: hydrogenation conversion with a catalyst in the suspension phase (KG); distillation or flash evaporation (MI), deasphalting (DA) is characterized by the fact that the three units operate on mixed flows consisting of fresh raw materials and return streams using the following stages:

- directing at least one fraction of the heavy feed to the deasphalting section (DA) in the presence of solvents, obtaining two streams, one consisting of deasphalted oil (DAM) and the other from asphaltenes;

- mixing the asphaltenes with the remaining fraction of the heavy raw materials not directed to the deasphalting section, and a suitable hydrogenation catalyst and directing the resulting mixture to the hydroprocessing reactor (KG), supplying it with hydrogen or a mixture of hydrogen and H ₂ S;

- the direction of the stream containing the product of the hydroprocessing reaction and the catalyst in the dispersed phase, to one or more than one stage of distillation or flash evaporation (MI), as a result of which most volatile fractions are separated, among which there are gases obtained from the hydroprocessing reaction, naphtha and gas oil ;

- a return of at least 60%, preferably at least 80%, more preferably at least 95%, of the distillation residue (resin) or liquid leaving the flash unit containing the dispersed phase catalyst rich in metal sulfides obtained by demetallization (demetallation) of raw materials, and possibly coke and various types of carbon-containing residues in the deasphalting zone.

It is usually necessary to liquefy the asphaltene stream leaving the deasphalting section (DA) to ensure that too many of all these elements do not accumulate in the hydrotreatment reactor and, in the event of catalyst deactivation, to allow the removal of a portion of the catalyst that is replaced with a fresh catalyst. However, this is usually not the case, since the catalyst remains active for a long time; Assuming that in any case, it is necessary to carry out a dilution for the reasons described above, part of the catalyst should obviously be consumed even if it is far from a complete loss of activity. Moreover, although the volumes of the fluidizing stream (0.5-4% relative to the feed) are quite limited in comparison with other hydroprocessing technologies, significant problems still exist regarding their use or disposal.

The described application, in particular, is suitable when heavy fractions of complex hydrocarbon mixtures obtained from the process (at the bottom of the distillation column) should be used as raw materials for catalytic cracking units, both hydrocracking (HA) and fluid-catalytic cracking ( FKK).

The combined action of the catalytic hydrogenation unit (CG) with the extraction process (DA) actually allows to obtain deasphalted oils with a reduced content of contaminants (metals, sulfur, nitrogen, carbon-containing residue), and therefore, which are easy to process in catalytic cracking processes.

However, another aspect to consider is that naphtha and gas oil, obtained directly from the hydroprocessing unit, still contain many contaminants (sulfur, nitrogen ...) and in any case they must be reprocessed to obtain the final products.

The subject of the present invention is a comprehensive method for the conversion of coal-containing raw materials into liquid products by sharing at least the following seven processing units: coal liquefaction (SU), flash evaporation or distillation of the product obtained by liquefaction (MI), solvent extraction to remove non-combustible substances (ER), distillation to separate the solvent (OR), hydrogenation conversion with catalysts in the suspension phase (KG), distillation or flash evaporation of the product obtained by the conversion of by refining (P), solvent deasphalting (DA), characterized in that it includes the following stages: - directing the raw materials containing coal to one or more stages (CS) of direct liquefaction of coal in the presence of a suitable hydrogenation catalyst in the dispersed phase, and hydrogen or hydrogen and H ₂ S; - the direction of the stream containing the product obtained from the coal liquefaction reaction, to one or more than one stage (MI) of instant evaporation or distillation, obtaining a gaseous stream and a liquid stream; - directing the liquid stream to the solvent extraction step (ER), resulting in an insoluble stream consisting of the mineral present in the feed and unreacted coal, and a liquid stream consisting of the obtained liquefied coal and the solvent used; - directing the liquid stream, consisting of liquefied coal and the solvent used, to one or more distillation stages to essentially separate the solvent contained in the liquid stream, which is returned to the solvent extraction step (ER); - mixing the liquid stream, essentially consisting of liquefied coal, and at least part of the stream containing asphaltenes obtained in the deasphalting unit, with a suitable catalyst in the dispersed phase and directing the resulting mixture to the hydroprocessing reactor (CH), feeding it hydrogen or a mixture hydrogen and H ₂ S; - optionally directing the stream containing the reaction product of the hydroprocessing and the catalyst in the dispersed phase to the preliminary separation stage, performed at high pressure, to obtain a light and heavy fraction; - the direction of the stream containing the product of the hydroprocessing reaction and the catalyst in the dispersed phase or the heavy fraction obtained through the separation stage at high pressure, to one or more stages (P) of distillation or flash evaporation, as a result of which the various fractions coming from the reaction are separated hydrotreatment; - the direction of at least a portion of the residue after distillation (resin) or liquid leaving the flash unit containing the catalyst in the dispersed phase, rich in metal sulfides obtained by demetallization of the feedstock, and possibly coke in the deasphalting zone (YES) in the presence of solvents, into which it is also possible to supply at least one fraction of a liquid stream essentially consisting of liquefied coal, producing two streams: one consisting of deasphalted oil (DAM) and the other containing asphaltenes.

The coal contained in the raw materials intended for processing at the stage of liquefaction, may be as such or, possibly, enriched by known techniques for the enrichment of coal.

The coal-containing feed is preferably a feed essentially consisting of coal.

A suitable hydrogenation catalyst present in the liquefaction (LI) step can be recovered at least partially by returning from blocks downstream from the indicated step (e.g., via a stream containing asphaltenes from the deasphalting step (YES), or part of the residue after distillation (resin) or liquid leaving the flash unit (P) containing a catalyst in the dispersed phase, rich in metal sulfides formed by demetallization of raw materials, and possibly coke).

The feedstock, essentially consisting of coal, is preferably suspended in a hydrocarbon matrix, which can come from blocks located downstream of the liquefaction (SU) stage: preferably part of the asphaltene-containing stream as well as the dispersed catalyst used in the hydroprocessing stage (KG) obtained at the stage of deasphalting (YES), and / or part of the stream consisting of deasphalted oil (DAM) obtained at the stage of deasphalting (YES).

At the stage of distillation (OR) of a liquid stream consisting of liquefied coal and the solvent used, it is possible to separate an additional stream as a distillation product, which can be added either partially or in whole to lighter fractions separated in distillation or flash units (П) .

Direct liquefaction of a stream containing coal can be carried out using one of the various known methods for liquefying coal.

It is recommended to directly liquefy a stream containing coal by mixing said stream with an aromatic solvent in an amount of from 20 to 80% with respect to coal and with a suitable catalyst in the dispersed phase, operating at a temperature in the range from 360 to 440 ° C, at a hydrogen pressure in the range from 3 to 30 MPa and a residence time of less than or equal to 4 hours

The aromatic solvent used preferably comes at least in part from one or more of the following return stream:

- part of the stream, consisting of deasphalted oil (DAM), obtained at the stage of deasphalting (YES);

- at least a portion of the stream containing asphaltenes, as well as a dispersed catalyst used in the hydroprocessing (CH) stage, obtained in the deasphalting (DA) stage;

- part of the medium and heavy fractions (medium and heavy distillation products) obtained in distillation or flash units (P);

- part of the solvent separated in the distillation unit (OR) is lower along the process with respect to the stage of removal of non-combustible substances (ER);

- part of the additional stream separated as a distillation product in the distillation unit (OR), lower in the process with respect to the stage of removal of non-combustible substances (ER).

The solvent extraction step (ER) in order to remove fireproof substances is preferably carried out at a temperature in the range of 150 to 350 ° C. and at a pressure in the range of 2 to 6 MPa (20 to 60 atm), in the presence of a suitable aromatic solvent.

As for the main method, it is also possible to add heavy raw materials selected from heavy crude oil, distillation residues, heavy oils from catalytic processing, thermal resins, tar sands, various types of coal and / or other high boiling hydrocarbon feedstocks, initially known as dark oils, to raw materials consisting of coal, intended to be sent to a liquefaction unit (SU), and / or to a liquid stream consisting of liquefied coal, intended to be directed to a hydroprocessing stage (KG).

In addition to the steps forming the integrated process, the section of the secondary post-treatment hydrogenation fraction may present a C ₂ - 500 ° C, preferably the fractions C ₅ - 350 ° C, formed from the separation zone at a high pressure, disposed upstream of the process with respect to the distillation .

In this case, the stream containing the product of the hydroprocessing reaction and the catalyst in dispersed form, before it is sent to one or more than one stage of distillation or flash evaporation, is subjected to a preliminary stage of separation performed at high pressure to obtain a light fraction and a heavy fraction, moreover only said heavy fraction is sent to said distillation step (s) (P).

The light fraction obtained by the high-pressure separation step can be sent to the hydrotreatment section to obtain a lighter fraction containing C ₁ -C ₄ and H ₂ S gas and heavier fractions containing hydrogenated naphtha and gas oil.

With the introduction of the secondary secondary treatment section by hydrogenation of the fraction

C ₂ - 500 ° C, preferably fractions C ₅ - 350 ° C, use the availability of this fraction together with hydrogen at a relatively high pressure, which is approximately the same as in the hydrotreatment reactor, which allows to obtain the following advantages:

- the production of fuels, starting from petroleum feedstocks, very rich in sulfur, in accordance with the most stringent requirements for sulfur content (<10-50 ppm sulfur) and improved in relation to other characteristics of diesel gas fuel, such as density, polyaromatic hydrocarbon content and cetane number;

- the resulting distillation products do not have stability problems.

The subsequent hydrogenation treatment in a fixed bed consists in preliminary separation of the reaction effluent from the hydroprocessing reactor (KG) using one or more separators operating at high pressure and high temperature. While the heavy part extracted in the lower part is sent to the main distillation unit, the part extracted in the upper part, the C ₂ -500 ° C fraction, preferably the C ₅ -350 ° C fraction, is sent to the secondary treatment section in the presence of hydrogen available at high pressure, in which the reactor is a fixed-bed reactor that contains a typical desulfurization / dearomatization catalyst to obtain a product having a much lower sulfur content and also lower nitrogen levels, lower overall density and, at the same time, when it comes to the gas oil fraction, an increased cetane number.

A hydrotreatment section typically consists of one or more than one series-connected reactor; the product of this system can be further fractionated by distillation to obtain fully desulfurized naphtha and diesel fuel, according to the specification as fuel.

In the fixed-bed hydrodesulfurization step, typical fixed-bed catalysts are usually used for hydrodesulfurization of gas oil; said catalyst, or possibly also a mixture of catalysts or a series of reactors with several catalysts having different properties, causes a deep purification of the light fraction, significantly lowering the content of sulfur and nitrogen, increasing the degree of hydrogenation of the feedstock, sequentially lowering the density, increasing the cetane number of the gas oil fraction, while while reducing coke formation.

The catalyst usually consists of an amorphous part based on alumina, silica, silico-alumina and mixtures of various mineral oxides onto which the hydrodesulphurizing component is deposited (in various ways) in combination with a hydrogenating agent. Catalysts based on molybdenum or tungsten with the addition of nickel and / or cobalt supported on an amorphous mineral support are typical catalysts for this type of process.

The hydrogenation reaction during subsequent processing is carried out at an absolute pressure slightly lower than the pressure at the initial stage of hydroprocessing, usually in the range from 7 to 14 MPa, preferably from 9 to 12 MPa; the desulfurization temperature is in the range from 250 to 500 ° C, preferably from 280 to 420 ° C; the temperature is usually selected depending on the desired degree of desulfurization. Space velocity is another important parameter in controlling the quality of the resulting product: it can vary in the range from 0.1 to 5 hours ^-1 , preferably from 0.2 to 2 hours ^-1 .

Hydrogen mixed with the feed is supplied at a flow rate in the range of 100 to 5000 m ³ at normal pressure / m ³ (Nm ₃ / m ₃ ), preferably 300 to 1000 m ³ at normal pressure / m ³ .

The additional secondary post-treatment section of the fluidizing stream may also be present separately or possibly together with the hydrogenation post-treatment section, in addition to the steps forming an integrated process.

The specified section of the secondary secondary subsequent processing consists of the subsequent processing of the fluidizing stream to significantly lower its category (entity) and to allow the return to the hydroprocessing reactor at least part of the still active catalyst.

In this case, the fraction of the stream containing asphaltenes coming from the deasphalting (DA) section, called the fluidizing stream, is sent to the treatment section with a suitable solvent to separate the product into a solid fraction and a liquid fraction, from which this solvent can subsequently be removed.

A possible treatment section for the diluent effluent, preferably in an amount of 0.5 to 10 vol.% With respect to fresh raw materials, consists of a solvent de-oiling step (toluene or gas oil or other streams rich in aromatic compounds) and separation of solid and liquid fractions.

At least a portion of said liquid fraction may be fed:

- into the fuel oil tank as such, or after separation from the solvent, and / or after the addition of suitable diluents;

- and / or to the hydroprocessing reactor (KG) as such.

In specific cases, the solvent and diluent may be the same.

The solid fraction can be removed as such or, more preferably, it can be sent for treatment to selectively recover the transition metal or metals contained in the transition catalyst (e.g., molybdenum) (with respect to other metals present in the initial residue, nickel and vanadium), with the possible return of the stream rich in transition metal (molybdenum) to the hydroprocessing reactor (KG).

This composite processing has the following advantages over the traditional method:

- the category of fluidizing fraction is greatly reduced;

- improve the quality of most of the fluidizing fraction to fuel oil by separating metals and coke;

- the fraction of fresh catalyst intended to be added to the feedstock for primary hydrotreatment is reduced, since at least part of the molybdenum extracted by selective extraction is returned.

The stage of de-oiling consists in processing the fluidizing stream, which is the minimum fraction of the asphaltene stream coming from the deasphalting section (DA) to the primary hydrotreatment unit for heavy raw materials, with a solvent that is able to transfer the greatest possible amount of organic compounds to the liquid phase, leaving metal sulfides, coke and more refractory carbon-containing residues (insoluble toluene or similar products) in the solid phase.

Considering that components of a metallic nature can become pyrophoric when they are very dry, it is recommended to work in an inert atmosphere containing as little oxygen and moisture as possible.

Various solvents may advantageously be used at this stage of de-oiling; among them, aromatic solvents such as toluene and / or xylene mixtures, hydrocarbon feeds available at the facility, such as gas oil produced at it, or at refineries such as light catalytic cracking oil coming from the FCC unit, or gas oil, obtained by thermal cracking coming from a cracking furnace for easy cracking / thermal cracking.

Within certain limits, the speed of operation is facilitated by increasing the temperature and reaction time, but excessive increase is not recommended for economic reasons.

Operating temperatures depend on the solvent used and the pressure conditions adopted; however, temperatures in the range of 80 to 150 ° C are recommended; the reaction time may be from 0.1 to 12 hours, preferably from 0.5 to 4 hours

The volume ratio of solvent to diluent stream is also an important parameter that must be taken into account; it may be from 1 to 10 (v / v), preferably from 1 to 5, more preferably from 1.5 to 3.5.

After completion of the mixing phase of the solvent and the dilution stream, the stream maintained with stirring is sent to the separation section of the liquid phase from the solid phase.

This operation may be one of those typically used in industry, such as decantation, centrifugation or filtration.

The liquid phase can then be directed to the stripping and recovery of the solvent phase, which is returned to the first processing step (de-oiling) of the fluidizing stream. The heavy fraction that remains can advantageously be used in refineries as a stream substantially free of metals and with a relatively low sulfur content. If the processing operation is carried out, for example, with gas oil, part of the specified gas oil can be left in the heavy product to bring it within the characteristics of the fuel oil tank.

Alternatively, the liquid fraction may be returned to the hydrogenation reactor.

The solid part can be removed as such, or it can be subjected to further processing in order to selectively remove the catalyst (molybdenum) intended to be returned to the hydrogenation reactor.

In fact, it was found that by adding heavy raw materials, but without metals, such as, for example, part of the deasphalted oil (DAM) coming from the deasphalting unit on the unit itself, to the above solid phase and mixing the specified system with acidified water (usually with using inorganic acid) almost all of the molybdenum is stored in the organic phase, while significant amounts of other metals move towards the aqueous phase. The two phases can be easily separated and then the organic phase can advantageously be returned to the hydrotreatment reactor.

The solid phase is dispersed in a sufficient amount of the organic phase (for example, deasphalted oil from the same process), to which acidified water is added.

The ratio between the aqueous and organic phases can be from 0.3 to 3; The pH of the aqueous phase may be from 0.5 to 4, preferably from 1 to 3.

It is possible to process various types of heavy raw materials that can be selected from heavy crude oil, bitumen from oil sands, various types of coals, distillation residues, heavy oils from catalytic processing, for example heavy catalytic cracking oils, lower hydrogenation conversion treatment products, thermal resins (coming from, for example, light cracking or similar thermal processes) and any other high-boiling raw materials of hydrocarbon origin, commonly known in the art as dark boiled oils.

When it comes to the conditions of the main method, reference should be made to what is already defined in patent applications IT-MI2001A-001438 and IT-95A001095.

According to what is described in patent application IT-95A001095, all heavy feedstocks can be mixed with a suitable hydrogenation catalyst and sent to a hydrotreatment reactor (KG), while at least 60%, preferably at least 80% of the asphaltene-containing stream, which also contains a dispersed phase catalyst, and possibly coke, and rich in metals from the feed, can be returned to the hydrotreatment zone.

According to what is described in patent application IT-MI2001A-001438, a part of the heavy feed and at least a large part of the asphaltene-containing stream, which also contains a dispersed phase catalyst and possibly coke, are mixed with a suitable hydrogenation catalyst and sent to a hydrotreatment reactor while the remaining amount of heavy raw materials is sent to the deasphalting section.

According to what is described in patent application IT-MI2001A-001438, at least a large part of the asphaltene-containing stream, which essentially consists of these asphaltenes, is mixed with a suitable hydrogenation catalyst and sent to a hydrotreatment reactor, while everything is heavy raw materials are fed to the deasphalting section.

When only a portion of the distillation residue (resin) or liquid leaving the flash unit is returned to the deasphalting zone (DSA), at least a portion of the remaining amount of the residue after distillation or flash evaporation can be sent to the hydroprocessing reactor together with at least part of a stream containing asphaltenes coming from a deasphalting section (YES).

The catalyst used can be selected from catalysts prepared from in situ decomposition precursors (metal naphthenates, metal derivatives of phosphonic acid, metal carbonyls, etc.), or from preformed compounds based on one or more than one transition metal, such like Ni, Co, Ru, W, and Mo; the latter is preferred due to its high catalytic activity.

The concentration of the catalyst, determined on the basis of the concentration of the metal or metals present in the hydrogenation conversion reactor, is in the range from 300 to 20,000 ppm, preferably from 1000 to 10,000 ppm.

The hydroprocessing step is preferably carried out at a temperature in the range from 370 to 480 ° C., more preferably from 380 to 440 ° C., and at a pressure in the range from 3 to 30 MPa, more preferably from 10 to 20 MPa.

Hydrogen is fed into a reactor that can operate with either a downward flow or, preferably, an upward flow. The specified gas can be supplied to various sections of the reactor.

The distillation step is preferably carried out at a residual pressure in the range from 0.0001 to 0.5 MPa, preferably from 0.001 to 0.3 MPa.

The hydroprocessing step may consist of one or more than one reactor operating in the range of conditions outlined above. Part of the distillation products obtained in the first reactor can be returned to subsequent reactors.

The deasphalting step carried out by extraction with a solvent, hydrocarbon or non-hydrocarbon (for example, paraffins or iso-paraffins having from 3 to 6 carbon atoms), is usually carried out at temperatures in the range from 40 to 200 ° C and at a pressure in the range from 0.1 up to 7 MPa. It may also consist of one or more than one section, working with the same solvent or with different solvents; solvent recovery can be performed under subcritical or supercritical conditions in one or more than one stage, thus allowing further separation into fractions of deasphalted oil (DAM) and resins.

The deasphalted oil (DAM) stream can be used alone as a synthetic crude oil, possibly mixed with distillation products, or it can be used as feedstock for fluid catalytic cracking or for hydrocracking treatment.

Depending on the characteristics of the crude oil (the content of metals, sulfur and nitrogen, the carbon-containing residue), the feed to the process as a whole can mainly be changed by sending a heavy residue, alternatively, either in asphalt blocking, in a hydroprocessing unit or in two plants simultaneously, while regulating:

- the ratio between the heavy residue sent to the hydroprocessing section (fresh raw materials) and this residue sent to deasphalting; said ratio is preferably from 0.01 to 100, more preferably from 0.1 to 10, most preferably from 1 to 5;

- the return ratio between fresh raw materials and resin sent to the deasphalting section; said ratio is preferably from 0.01 to 100, more preferably from 0.1 to 10;

- the return ratio between fresh raw materials and asphaltenes sent to the hydroprocessing section; the specified ratio may vary depending on previous ratios;

- the return ratio between the resin and the asphaltenes sent to the hydroprocessing section; the specified ratio may vary depending on previous ratios.

This flexibility is especially useful for making full use of the additional characteristics of the deasphalting unit (separate reduction of nitrogen and dearomatization) and the hydrotreating unit (high degree of metal and sulfur recovery).

Depending on the type of crude oil, the stability of these streams and the quality of the product obtained (also for a separate downstream treatment), the fractions of fresh raw materials to be fed to the deasphalting section and the hydrotreating section can be controlled in the best possible way.

The described application is especially suitable when the heavy fractions of complex hydrocarbon mixtures obtained in the method (in the lower part of the distillation column) are intended for use as raw materials for catalytic cracking units, both hydrocracking (HC) and fluid catalytic cracking (FCC) .

The combined action of the catalytic hydrogenation unit (CG) with the extraction process (DA) allows to obtain deasphalted oils with a reduced content of contaminants (metals, sulfur, nitrogen, carbon-containing residue), and therefore, which can be more easily processed in catalytic cracking processes.

The following is a preferred embodiment of the present invention using the attached drawing, which, however, should in no way be construed as limiting the scope of the invention itself.

Raw material (1), essentially consisting of coal, after it is previously suspended in a hydrocarbon matrix, a suitable solvent (2) and an appropriate hydrogenation catalyst (3) are sent to a direct liquefaction unit (CS), to which hydrogen or hydrogen and H are fed ₂ S (4), and from which a stream (5) flows, which is subjected to flash stage (MI) to obtain a gaseous stream (6) and a carbon-containing liquid stream (7).

The carbon-containing stream (7) is fed into the solvent extraction unit (ER), resulting in an insoluble stream (8) consisting of the mineral present in the feed and unreacted coal, and a liquid stream (9) consisting of the obtained liquefied coal and used solvent, and the last stream (9) is directed in turn to the stage (OR) of distillation to separate the solvent (10) contained in it, which is intended to return to the stage (ER) of extraction, from the additional liquid stream (11).

The additional stream (12) can be separated during distillation and it is possible to add (13) to the lighter fractions separated during distillation or in block (P) of flash evaporation and / or return (14), as a solvent, to the block (CS) of liquefaction .

A liquid stream (11) consisting of liquefied coal mixed with a suitable hydrogenation catalyst (15) is fed to the hydrotreatment unit (KG), introducing hydrogen and H ₂ S (16) into it, from which a stream (17) containing hydrogenation products is obtained and a dispersed phase catalyst, which is separated into fractions in a distillation column (P), where lighter fractions (18) are separated, together with distillation products (19), (20) and (21), from residue (22) after distillation containing a dispersed catalyst and coke.

The specified residue (22) after distillation, called resin, is sent to the deasphalting unit (YES), so as to obtain two streams: one stream (23) consisting of deasphalted oil (DAM), the other stream (24) consisting of asphaltenes, which it is possible to partially or completely add (25) to a liquid stream (11) consisting of liquefied coal, and it is possible to partially return (26) to a feed essentially consisting of coal (1).

The following are some examples to better illustrate the invention, but which should in no way be construed as limiting the scope of the invention itself.

EXAMPLE 1

The following experiment was carried out, following the scheme shown in the drawing.

Liquefaction stage

- Reactor: 30 cm ³ made of steel, equipped with a capillary mixing system and the possibility of adding (reintegrating) hydrogen.

- Raw materials: 5.0 g of Columbian El Cerrejon coal (table 1).

- Solvent: 5.0 g of DAM hydrogenated.

- Catalyst: 200 ppm Mo (introduced as a hydrosoluble precursor).

- Temperature: 400 ° C.

- Stay: 2 hours

- Pressure: 15 MPa.

The coal liquefaction step was performed according to the operating conditions indicated above. When the tests were completed, the reaction was suppressed; pressure was reduced in an autoclave and gases were collected in a soft sampling tank for gas chromatographic analysis. Non-gaseous products present in the reactor were recovered using tetrohydrofuran (THF) and filtered on 0.5 μm Teflon filters to eliminate THF insoluble components consisting of inorganic materials (non-combustible substances) from the unreacted organic fraction and catalyst.

The degree of conversion was calculated according to the following equation:

The degree of conversion = (coal _bvz - NOV) / (coal _bvz ) · 100.

In the formula above, the mass of coal is given on the basis of the mass of BVZ (without moisture and ash), i.e. the mass of non-combustible substances and water was subtracted from the total mass of coal. "NOV" (insoluble organic matter) refers to the mass of products insoluble in THF, recovered at the end of the reaction, from which the masses of non-combustible substances and water were subtracted.

Stage hydrotreatment of liquids from coal:

- Reactor: 30 cm ³ made of steel, equipped with a capillary mixing system and the possibility of adding hydrogen.

- Raw materials: 10 g of liquids from coal obtained in the liquefaction stage.

- Solvent: 5.0 g of DAM hydrogenated.

- Catalyst: 3000 ppm Mo (introduced as a hydrosoluble precursor).

- Temperature: 415 ° C.

- Stay: 4 hours

- Pressure: 16 MPa.

When the tests were completed, the reaction was suppressed; pressure was reduced in an autoclave and gases were collected in a soft sampling tank for gas chromatographic analysis. The non-gaseous products present in the reactor were recovered with THF and filtered on 0.5 μm Teflon filters to separate THF insoluble components consisting of catalyst, metal sulfides and possibly traces of coke formed. The THF-soluble fraction was then treated with an excess of n-pentane to precipitate C ₅ asphaltenes to obtain DAM (deasphalted oil) for analysis by simulated distillation gas chromatography (GC SIM-DIST) to determine the products of distillation, or to quantify outputs for:

- naphtha (boiling point PI-170 ° C),

- atmospheric gas oil (170-350 ° C),

- vacuum gas oil (350-500 ° C),

- vacuum residue (500 ° C +).

Experimental results

Data relating to the liquefaction step and subsequent hydrogenation treatment are shown in Table 2.

Table 1 Coal characteristics Coal Humidity, wt.% Volatile, wt.% Ash content, wt.% FROM N N S EI Cerrejon Columbia 5.25 35.46 4.71 73.7 5.35 1.41 0.61 table 2 Liquefaction and Hydrotreating Test Results Type of test The degree of conversion, wt.% Insoluble in THF, wt.% Asphaltenes C ₅ , wt.% C ₁ -C ₄ , wt.% C ₅ -170 ° C, wt.% 170-350 ° C, wt.% 350-500 ° C, wt.% 500 ° C + wt.% Liquefaction stage 81 8.7 37.9 1.4 - - - - Hydroprocessing stage - 1,0 4.1 2.6 0.2 10,2 27.0 40.5

EXAMPLE 2

Carry out the same procedure as described in Example 1; 5.0 g of coal is treated together with 5.0 g of DAM solvent in the presence of a solid mixture containing molybdenum sulfide, metal sulfides and heavy carbon-containing material. The above mixture is isolated from raw material hydrotreatment tests and represents part of the bottom of the deasphalting column (“fluidizing” flow according to the drawing). An amount of the mixture is introduced into the reactor so as to obtain a molybdenum concentration of 200 ppm.

Table 3 shows the data related to coal liquefaction tests.

Table 3 Liquefaction Test Result Type of test The degree of conversion, wt.% Insoluble in THF, wt.% Asphaltenes C ₅ , wt.% C ₁ -C ₄ , wt.% Liquefaction stage 79 10.6 38,2 1,5

EXAMPLE 3

The following experiments were performed, following the scheme shown in the drawing.

Liquefaction stage

- Reactor: 3000 cm ³ made of steel, equipped with a magnetic stirring system and the possibility of adding hydrogen.

- Raw materials: 250 g of coal (table 1).

- Solvent: 250 g LKG (light catalytic gas oil).

- Catalyst: 500 ppm Mo (introduced as a hydrosoluble precursor).

- Temperature: 415 ° C.

- Stay: 4 hours

- Pressure: 16 MPa.

When the test was completed, the reaction was suppressed; the pressure was reduced in the autoclave and gases were collected in a soft sampling tank for gas chromatographic analysis.

The product was recovered from the reactor and subjected to filtration to separate THF-insoluble components consisting of inorganic materials (non-combustible substances) from the unreacted organic fraction and the catalyst.

The liquefaction step was repeated several times to obtain an amount of liquid sufficient for subsequent hydroprocessing tests.

Provide a link to the data shown in Tables 2 and 3 for the results in terms of coal conversion.

Flash stage

The light fraction (350 ° C.-), consisting of the solvent used in the liquefaction step, and the distillation products formed by the reaction were separated by periodic distillation.

Hydroprocessing stage

The hydroprocessing reaction was carried out under the conditions indicated in Example 1 using the product obtained in the flash step (bottom of the column, residue 350 ° C +).

Gaseous products were separated at the end of the hydrogenation step. The product was then deasphalted with liquid propane. The resulting DAM _{3 was} then separated and recovered. Eight consecutive hydroprocessing tests were performed, using for each test a feed consisting of residues of 350 ° C + obtained from coal liquefaction and C ₃ asphaltenes obtained from the previous hydrotreatment and subsequent deasphalting stage containing a catalyst so as to allow a complete return of the catalyst, added during the first test. At each stage, the amount of residue from coal liquids was added, so as to continuously work with the same total amount of feed (approximately 300 g).

The ratio between the amount of carbon liquids and the amount of product returned achieved under these operating conditions was 1: 1.

Data related to the effluents after the last return (wt.% In relation to the input liquid raw materials) are shown below:

- gas: 7%

- naphtha (C ₅ - 170 ° C): 8%,

- atmospheric gas oil (AG 170-350 ° C): 19%,

- deasphalted oil (VG + DAM): 66%.

In this example, there was no need to liquefy the return stream.

Claims (50)

1. An integrated method for converting coal-containing raw materials into liquid products by sharing at least the following seven process units: coal liquefaction (SU), flash evaporation or distillation of a product obtained from liquefaction (MI), solvent extraction to remove non-combustible substances (ER) distillation to separate the solvent (OR), hydrogenation conversion with catalysts in the suspension phase (KG), distillation or flash evaporation of the product obtained by hydrogenation conversion (P), deasphalting with solution spokesman (YES), characterized in that the method includes the following stages:
directing the coal-containing feed to one or more than one stage (GC) of direct liquefaction of the coal in the presence of a suitable hydrogenation catalyst in the dispersed phase, as well as hydrogen or hydrogen and H ₂ S,
directing the stream containing the product obtained from the coal liquefaction reaction to one or more than one (MI) flash or distillation step (MI) to obtain a gaseous stream and a liquid stream,
directing the liquid stream to the solvent extraction step (ER), resulting in an insoluble stream consisting of the mineral present in the feed and unreacted coal, and a liquid stream consisting of the obtained liquefied coal and the solvent used,
directing the liquid stream, consisting of liquefied coal and the solvent used, to one or more distillation stages in order to essentially separate the solvent contained in the liquid stream, which is returned to the solvent extraction step (ER);
mixing a liquid stream essentially consisting of liquefied coal and at least part of a stream containing asphaltenes obtained in a deasphalting unit with a suitable catalyst in the dispersed phase and directing the resulting mixture to a hydrotreatment reactor (CH), feeding it hydrogen or a mixture of hydrogen and H ₂ S,
optionally directing the stream containing the product of the hydroprocessing reaction and the catalyst in the dispersed phase to the preliminary separation stage, performed at high pressure, to obtain light and heavy fractions,
directing the stream containing the hydroprocessing reaction product and the dispersed phase catalyst or the heavy fraction obtained by the high pressure separation step into one or more than one step, (P) distillation or flash evaporation, whereby the various fractions from the reaction are separated hydrotreatment
the direction of at least a portion of the distillation residue (resin) or liquid leaving the flash unit containing the dispersed phase catalyst rich in metal sulfides obtained by demetallization of the feed, and possibly coke, into the deasphalting zone (YES) in the presence of solvents, into which it is also possible to supply at least one fraction of a liquid stream essentially consisting of liquefied coal to produce two streams; one consisting of deasphalted oil (DAM), and the other containing asphaltenes. 2. The method according to claim 1, in which the raw material containing coal essentially consists of coal. 3. The method according to claim 1, in which a suitable hydrogenation catalyst present in the stage (CS) liquefaction, at least partially removed from the blocks located downstream of the specified stage. 4. The method according to claim 2, in which the feedstock, essentially consisting of coal, is suspended in a hydrocarbon matrix. 5. The method according to claim 4, in which the hydrocarbon matrix comes from blocks located downstream of the liquefaction stage (CS). 6. The method according to claim 5, in which the hydrocarbon matrix is part of a stream containing asphaltenes, as well as a catalyst used in the hydroprocessing stage (KG) and obtained in the deasphalting stage (YES), and / or a part of the stream consisting of deasphalted oil (DAM) obtained at the stage of deasphalting. 7. The method according to claim 1, in which the direct liquefaction of the stream containing coal, is performed by mixing the specified stream with an aromatic solvent in an amount in the range from 20 to 80% with respect to coal, and with a suitable catalyst in the dispersed phase, working at a temperature in the range from 360 to 440 ° C, at a hydrogen pressure of 3 to 30 MPa and with a residence time of less than or equal to 4 hours 8. The method according to claim 1, in which a portion of the stream containing asphaltenes, as well as the catalyst used in the hydrotreatment stage (KG) and obtained in the deasphalting stage (YES), are added to the raw material containing coal, intended to be sent to the block ( SU) liquefaction, as a solvent. 9. The method according to claim 1, in which a portion of the stream consisting of deasphalted oil (DAM) obtained in the deasphalting stage (YES) is added to the coal-containing raw material intended to be sent to the liquefaction unit (SU) as a solvent. 10. The method according to claim 1, in which part of the medium and heavy fractions (medium and heavy distillation products) obtained in the unit (P) for distillation or flash evaporation are added to the coal-containing raw material intended to be sent to the liquefaction unit (CS), as a solvent. 11. The method according to claim 1, in which a portion of the solvent separated in the (OR) distillation step is added to the coal-containing feed intended to be sent to the liquefaction unit (CS) as a solvent. 12. The method according to claim 1, in which at the stage (OR) distillation of a liquid stream consisting of liquefied coal and the solvent used, the additional stream is separated as a distillation product. 13. The method according to p. 12, in which a part of the distillation separated off at the (OP) stage as a distillation product of the additional stream is added to the raw material containing coal, intended to be sent to the liquefaction unit (SU) as a solvent. 14. The method according to claim 1, in which the stage of extraction with a solvent to remove non-combustible substances is performed at a temperature in the range from 150 to 350 ° C and a pressure in the range from 2 to 6 MPa (from 20 to 60 atm.), In the presence of a suitable aromatic solvent. 15. The method according to claim 1, in which heavy raw materials selected from heavy crude oil, residues after distillation, heavy oils coming from catalytic processing, thermal resins, bitumen from oil sands, various types of coal and / or other high-boiling hydrocarbon feedstocks , known as fermented oils, are added to the coal-containing feed intended to be sent to the liquefaction unit (CS) as a solvent. 16. The method according to claim 1, in which heavy raw materials selected from heavy crude oil, residues after distillation, heavy oils coming from catalytic processing, thermal resins, bitumen from oil sands, various types of coal and / or other high-boiling raw materials of hydrocarbon origin , known as dark oils, are added to the liquid stream, consisting of liquefied coal, intended to be directed to the hydroprocessing stage (KG). 17. The method according to claim 1, in which the light fraction obtained by the separation stage at high pressure, is sent to the secondary secondary processing section by hydrogenation, obtaining a lighter fraction containing gas C ₁ -C ₄ and
H ₂ S, and a heavier fraction containing hydrogenated naphtha and gas oil. 18. The method according to 17, in which the reaction of the subsequent hydrogenation treatment is performed at a pressure in the range from 7 to 14 MPa. 19. The method according to claim 1, in which the entire liquid stream, essentially consisting of liquefied coal, is mixed with a suitable hydrogenation catalyst and sent to a hydrotreatment reactor (KG), while at least 60% of the stream containing asphaltenes, which also contains a catalyst in the dispersed phase and, possibly, coke and is enriched with metals coming from the feedstock, returned to the hydroprocessing zone. 20. The method according to claim 19, in which at least 80% of the asphaltene-containing stream is returned to the hydrotreatment zone. 21. The method according to claim 1, in which a liquid stream essentially consisting of liquefied coal, and at least a large part of the stream containing asphaltenes, which also contains a dispersed phase catalyst and possibly coke, are mixed with a suitable hydrogenation catalyst and sent to the hydroprocessing reactor (KG). 22. The method according to claim 1, in which part of the residue after distillation (resin) or liquid leaving the flash unit (P) is sent to the deasphalting zone (YES) and at least part of the remaining part of the specified residue after distillation or flash evaporation is directed to the hydroprocessing reactor. 23. The method according to item 22, in which at least part of the remaining amount of the residue after distillation (P) or flash evaporation is sent to the hydroprocessing reactor together with at least part of the stream containing asphaltenes coming from the deasphalting section (YES). 24. The method according to claim 1, in which at least 80 wt.% Of the residue after distillation is sent to the deasphalting zone (YES). 25. The method according to paragraph 24, in which at least 95 wt.% The residue after distillation is sent to the deasphalting zone (YES). 26. The method according to claim 1, in which at least part of the remaining amount of the residue after distillation (resin), not directed to the deasphalting zone, is returned to the hydrotreatment section (KG). 27. The method according to claim 1, in which the stage of distillation is carried out under reduced pressure in the range from 0.0001 to 0.5 MPa. 28. The method according to item 27, in which the stage of distillation is carried out under reduced pressure in the range from 0.001 to 0.3 MPa. 29. The method according to claim 1, in which the stage of hydroprocessing is carried out at a temperature in the range from 370 to 480 ° C and at a pressure in the range from 3 to 30 MPa. 30. The method according to clause 29, in which the stage of hydroprocessing is carried out at a temperature in the range from 380 to 440 ° C and at a pressure in the range from 10 to 20 MPa. 31. The method according to claim 1, in which the stage of deasphalting is carried out at a temperature in the range from 40 to 200 ° C and at a pressure in the range from 0.1 to 7 MPa. 32. The method according to claim 1, in which the deasphalting solvent is light paraffin with a carbon number from 3 to 7. 33. The method according to claim 1, in which the stage (YES) deasphalting is carried out under subcritical or supercritical conditions, in one or more than one stage. 34. The method according to claim 1, in which a stream consisting of deasphalted oil (DAM) is fractionated by conventional distillation. 35. The method according to claim 1, in which the stream, consisting of deasphalted oil (DAM), is mixed with products separated in the distillation stage, after condensation. 36. The method according to claim 1, in which the hydrogenation catalyst is obtained from a decomposable precursor or preformed compound based on one or more than one transition metal. 37. The method according to clause 35, in which the transition metal is molybdenum. 38. The method according to claim 1, in which the concentration of the catalyst in the hydrogenation conversion reactor, determined based on the concentration of the present metal or metals, is in the range from 300 to 20,000 ppm. 39. The method according to § 38, in which the concentration of the catalyst in the conversion reactor by hydrogenation is in the range from 1000 to 10000 ppm. 40. The method according to claim 1, in which the fraction of the stream containing asphaltenes coming from the deasphalting section (YES), called the fluidizing stream, is sent to the treatment section with a suitable solvent to separate the product into a solid fraction and a liquid fraction, from which it can subsequently be separated solvent. 41. The method according to p, in which the amount of fluidizing stream is in the range from 0.5 to 10 vol.% In relation to fresh raw materials. 42. The method according to paragraph 41, in which at least part of the liquid fraction obtained in the processing section of the fluidizing stream is added to the fuel oil fraction as such, or after separation of the solvent and / or addition of a suitable diluent. 43. The method according to § 42, in which at least part of the liquid fraction obtained in the processing section of the fluidizing stream is returned to the hydroprocessing reactor (KG) and / or at least part of the liquid fraction obtained in the processing section of the fluidizing stream is returned to coal liquefaction unit (SU). 44. The method according to p, in which the solvent used in the processing section of the fluidizing stream, is an aromatic solvent or a mixture of gas oils obtained in the process, or available in oil refineries. 45. The method according to item 44, in which the aromatic solvent is toluene and / or a mixture of xylenes. 46. The method according to § 38, in which the volume ratio of the solvent and the fluidizing stream is from 1 to 10. 47. The method according to item 46, in which the volume ratio of the solvent and the fluidizing stream is from 1 to 5. 48. The method according to clause 47, in which the volume ratio of the solvent and the fluidizing stream is from 1.5 to 3.5. 49. The method according to p, in which the solid fraction of the processed product is sent for further processing in order to selectively recover the transition metal or metals contained in the hydrogenation catalyst. 50. The method according to 49, in which the extracted transition metal or metals are returned to the hydroprocessing reactor (KG).