Process for producing middle fraction

Abstract

The present invention relates to a process for producing a middle fraction from a feedstock comprising a residual hydrocarbon-containing feedstock and a hydrogen-depleted feedstock. The process comprises the steps of: (a) deasphalting the residual hydrocarbon-containing feedstock to obtain a deasphalted product in which at least 50 wt% of the deasphalted product has a boiling point above 550 DEG C and an asphalted product; (b) mixing the deasphalted product with the hydrogen-depleted feedstock to produce a mixed deasphalted product, wherein the hydrogen (H) content of the hydrogen-depleted feedstock is at least 6 wt% to at most 11.3 wt%; (c) hydrodemetallizing at least a portion of the mixed deasphalted product from step (b) to produce a hydrodemetallized product; (d) hydrotreating at least a portion of the hydrodemetallization product from step (c) to produce a hydrotreated product; (e) hydrocracking at least a portion of the hydrotreated product from step (d) to produce a hydrocracked product; and (f) subjecting at least a portion of the hydrocracking product from step (e) to a separation treatment to produce at least one middle fraction.

Description

Technical Field

[0001] The present invention relates to a process for producing middle distillates from a residual hydrocarbonaceous feed and a hydrogen-depleted feed. Background Art

[0002] In view of the growing environmental awareness of reducing the carbon footprint of processes, much research and development is devoted to improving the yield of middle distillates and the processing of low hydrogen content feeds, which will increase the production of ultra-low sulfur middle distillates (such as ultra-low sulfur diesel fuel), which may contain some portion of renewable origin.

[0003] As is well known, the process for producing ultra-low sulfur diesel fuel is to first hydrodesulfurize a hydrocarbon fraction stream having a boiling point within the boiling range of gas oil, and then catalytically dewax the desulfurized fraction stream. Particularly in winter, a catalytic dewaxing step may be required to remove waxy molecules from the fraction stream to reduce the cloud point and pour point of the gas oil. The desulfurized and dewaxed gas oil can be hydrofined to saturate the aromatic compounds. In this way, the cetane index or cetane number of the gas oil product can be further increased. The resulting desulfurized, dewaxed and optionally hydrofined gas oil is then used as a diesel fuel or a diesel fuel component.

[0004] The object of the present invention is to provide a process for producing an ultra-low sulfur middle distillate with high yield and introducing a hydrogen-depleted feed. Summary of the invention

[0005] This object is achieved when a specific multi-step process is used. The present invention therefore relates to a process for producing a middle distillate from a feedstock comprising a residual hydrocarbonaceous feedstock and a hydrogen-depleted feedstock, the process comprising the following steps:

[0006] (a) deasphalting the residual hydrocarbonaceous feedstock to obtain a deasphalted product and an asphalt product wherein at least 50% by weight of the deasphalted product has a boiling point greater than 550° C.;

[0007] (b) mixing the deasphalted product with the hydrogen-depleted feedstock to produce a mixed deasphalted product, wherein the hydrogen (H) content of the hydrogen-depleted feedstock is at least 6 wt % and at most 11.3 wt %;

[0008] (c) hydrodemetallizing at least a portion of the mixed deasphalted product from step (b) to produce a hydrodemetallized product;

[0009] (d) hydroprocessing at least a portion of the hydrodemetallized product from step (c) to produce a hydroprocessed product;

[0010] (e) hydrocracking at least a portion of the hydrotreated product from step (d) to produce a hydrocracked product; and

[0011] (f) subjecting at least a portion of the hydrocracked product from step (e) to a separation treatment to produce at least one middle distillate fraction.

[0012] According to the present invention, a middle distillate having a sulfur content of less than 10 ppm wt can be advantageously produced in high yield from a residual hydrocarbonaceous feedstock and a hydrogen-depleted feedstock. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a simplified block flow diagram of an embodiment of a process for producing middle distillates from a residual hydrocarbonaceous feed and a hydrogen-depleted feed.

[0014] Figure 2 is a simplified block flow diagram of an alternative embodiment of a process for producing middle distillates from a residual hydrocarbonaceous feed and a hydrogen-depleted feed.

[0015] Figure 3 is a simplified block flow diagram of an alternative embodiment of a process for producing middle distillates from a residual hydrocarbonaceous feed and a hydrogen-depleted feed.

[0016] Figure 4 is a simplified block flow diagram of an alternative embodiment of a process for producing middle distillates from a residual hydrocarbonaceous feed and a hydrogen-depleted feed. DETAILED DESCRIPTION

[0017] The residual hydrocarbon-containing feedstock used according to the present invention may be a residual hydrocarbon oil, such as those obtained when distilling crude oil at atmospheric or reduced pressure. Suitably, at least 55% by weight, preferably at least 75% by weight, more preferably at least 85% by weight, even more preferably at least 90% by weight of the residual hydrocarbon-containing feedstock has a boiling point above 550°C. However, atmospheric residue or vacuum residue contains a considerable amount of non-distillable compounds with high molecular weight, such as asphaltenes. Therefore, it is desirable to remove asphaltenes from the residual hydrocarbon oil feed before subjecting the residual hydrocarbon oil to a subsequent upgrading step.

[0018] In step (a), the residual hydrocarbonaceous feedstock is deasphalted to obtain a deasphalted product and an asphalt product, wherein at least 50 wt. %, preferably at least 70 wt. %, more preferably at least 80 wt. %, even more preferably at least 85 wt. % of the deasphalted product has a boiling point above 550° C.

[0019] The deasphalting in step (a) can be carried out in any conventional manner. A well known and suitable deasphalting process is solvent deasphalting. According to the present invention, the deasphalting in step (a) is preferably carried out by a solvent deasphalting process.

[0020] In solvent deasphalting, hydrocarbon feed is processed in countercurrent using an extraction medium, which is typically a light hydrocarbon solvent containing paraffin compounds. Commonly used paraffin compounds include C3-8 paraffins, such as propane, normal butane, isobutane, normal pentane, isopentane, hexane or a mixture of two or more of these. For purposes of the present invention, C3-C5 paraffins are preferably used, most preferably butane, pentane or a mixture thereof are used as extraction solvents. Typically, extraction depth increases with the increase of the carbon number of the extraction solvent. In this regard, it is noteworthy that the deeper the extraction depth, the greater the amount of hydrocarbons extracted from the residual hydrocarbonaceous feedstock, the smaller and more viscous the asphaltene product is, and the asphaltene in the asphalt product to be obtained in step (a) is heavier.

[0021] In the solvent deasphalting process, a rotating disc contactor or a plate tower can be used, wherein the residual hydrocarbonaceous feedstock enters at the top and the extraction solvent enters at the bottom. The lighter hydrocarbons present in the residual hydrocarbonaceous feedstock are dissolved in the extraction solvent and taken out at the top of the device as a deasphalted product. Asphaltenes that are insoluble in the extraction solvent are taken out at the bottom of the device in the form of an asphalt product. The conditions under which deasphalting occurs are known in the art. Suitably, deasphalting is carried out at a ratio of total extraction solvent to residual hydrocarbon oil of 1.5 wt / wt to 8 wt / wt, a pressure of 1 bara to 60 bara, and a temperature of 40° C. to 200° C.

[0022] The deasphalting process generally results in a large amount of metal contaminants present in the feed being accumulated in the asphalt product as high molecular weight complexes rather than in the deasphalted product. Nevertheless, the metal content of the deasphalted product will necessitate a hydrodemetallization step before the deasphalted product can be subjected to further hydroprocessing upgrading steps.

[0023] In step (b), at least a portion of the deasphalted product is mixed with a hydrogen-depleted feedstock to produce a mixed deasphalted product. Preferably, in step (b), all of the deasphalted product obtained in step (a) is mixed with a hydrogen-depleted feedstock. Adding a hydrogen-depleted feedstock can reduce the carbon footprint of the process by utilizing low-value products from other processes and increasing the amount of middle distillate products.

[0024] In some embodiments, the hydrogen content of the mixed deasphalted product should be less than at least 0.1% by weight of the deasphalted product by adding a hydrogen-depleted feedstock. In other embodiments, the hydrogen content of the mixed deasphalted product should be at most 2% lower than the deasphalted product by adding a hydrogen-depleted feedstock. In some embodiments, the amount of the hydrogen-depleted feedstock is at most about 50% by weight of the mixed deasphalted product, or at most about 40% by weight of the mixed deasphalted product, or at most about 30% by weight of the mixed deasphalted product.

[0025] The deasphalted product from step (a) is a heavy deasphalted product. This means that at least 50 wt. %, preferably at least 70 wt. %, more preferably at least 80 wt. %, even more preferably at least 85 wt. % of the deasphalted product to be treated in step (b) has a boiling point above 550°C.

[0026] The hydrogen (H) content of the hydrogen-depleted feedstock is at least 6 wt% to at most 11.3 wt%, and its 10 wt% true boiling point chromatographic (TBP-GLC) distillation temperature is more than 280° C. Examples of such hydrogen-depleted feedstocks may be slurry oil from a fluid catalytic cracker unit, tall oil pitch from crude tall oil distillation, ethylene cracking residue from fossil fuels and / or waste plastic feedstock. In some embodiments, the waste plastic feedstock may be treated by pyrolysis and / or hydrotreatment before being fed to the ethylene cracker.

[0027] Slurry oil is the bottom product of the main distillation column from a fluid catalytic cracker (FCC) and is a blending component of marine fuel. The relative viscosity of slurry oil is between 5 cSt @ 100C and 25 cSt @ 100C, and the total aromatic content is between 35 wt% and 65 wt%. The hydrogen content of hydrogen-depleted slurry oil is about 8.2 wt% to about 9.2 wt%. The 10 wt% TBP-GLC distillation temperature of slurry oil is about 360°C (680°F).

[0028] Tall oil pitch (TOP) is a by-product of the distillation of crude tall oil (CTO). Currently, one application of TOP is as a bioheating fuel or as a substitute for fossil non-renewable energy. CTO is a by-product of the paper industry, which processes wood pulp from pine trees. The hydrogen content of hydrogen-depleted TOP is about 10.7 wt% to 11.1 wt%, and the 10 wt% TBP-GLC distillation temperature of TOP is at least 350°C (662°F). The viscosity range of TOP at 70°C is between 60 cSt and 100 cSt. Renewable asphalt can be converted into valuable products, including automotive fuel, using TOP. TOP is considered a renewable feed component and will provide carbon credits.

[0029] In step (c), at least a portion of the mixed deasphalted product obtained in step (b) is subjected to hydrodemetallization to obtain a hydrodemetallized product. Preferably, in step (c), all of the mixed deasphalted product obtained in step (b) is subjected to hydrodemetallization.

[0030] The hydrodemetallization of the mixed deasphalted product in step (c) can be achieved by any well-known hydrodemetallization process, wherein the mixed deasphalted product to be hydrodemetallized is passed through one or more vertically arranged reactors containing a fixed bed or a moving bed of hydrodemetallization catalyst particles at elevated temperature and pressure and in the presence of hydrogen in an upward, downward or radial direction. In one embodiment, the hydrogen used for the hydrodemetallization reaction can be generated, for example but not limited to, by water electrolysis. The water electrolysis process can be powered by renewable energy (such as solar photovoltaic, wind or hydroelectric power) to generate green hydrogen, nuclear energy, or powered by non-renewable energy (grey hydrogen) from other sources.

[0031] The hydrodemetallization may be carried out in a silo flow reactor, a fixed bed reactor, a fixed bed swing reactor or a moving bed reactor. Preferably, the hydrodemetallization in step (c) is at least partially carried out in a silo flow reactor or a moving bed reactor.

[0032] In step (c), a hydrodemetallization catalyst is used. Suitable hydrodemetallization catalysts used according to the present invention consist of an oxidic support, such as alumina, silica or silica-alumina, on which one or more Group VIB or Group VIII metals or metal compounds may be deposited. Such hydrodemetallization catalysts are commercially available from many catalyst suppliers. Particularly suitable hydrodemetallization catalysts are those catalysts that are promoted with one of a nickel / molybdenum (NiMo) or cobalt / molybdenum (CoMo) combination as an activator on an alumina (Al2O3) support, optionally with phosphorus (P). Specific examples of particularly suitable catalysts are CoMo / Al2O3, CoMoP / Al2O3 and NiMo / Al2O3 and NiMoP / Al2O3 catalysts.

[0033] Suitably, the hydrodemetallization in step (c) may be carried out at a hydrogen partial pressure of 20 bara to 300 bara, preferably 50 bara to 210 bara, at a temperature of 300°C to 460°C, preferably 310°C to 435°C, and at a space velocity of 0.1 hr-1 to 10 hr-1, preferably 0.2 hr-1 to 7 hr-1. In some embodiments, the use of a pure heavy deasphalted product in step (c) will result in a large amount of metal being deposited on the hydrodemetallization catalyst to be used in step (c), which in turn results in a very rapid degradation / deactivation of the hydrodemetallization catalyst, which requires a more regular and rapid replacement of the hydrodemetallization catalyst compared to known methods. In known methods, a diluted lighter deasphalted product with a lower metal content is subjected to a hydrodemetallization step. Therefore, the hydrodemetallization reactor is preferably a silo flow reactor, a fixed bed swing reactor, or a moving bed reactor. The hydrodemetallization catalyst is replaced regularly, for example, once every three weeks or two months. In conventional processes, the hydrodemetallization catalyst (such as the hydrotreating and hydrocracking catalysts used in steps (d) and (e) of the present process) may not be replaced for one year.

[0034] In step (d), at least a portion of the hydrodemetallized product obtained in step (c) is hydrotreated to obtain a hydrotreated product. Preferably, in step (d), all of the hydrodemetallized product obtained in step (c) is hydrotreated.

[0035] The hydrotreatment of the hydrodemetallized product in step (d) can be achieved by any well-known hydrotreatment method, wherein the hydrodemetallized product to be hydrotreated is passed through one or more vertically arranged reactors at elevated temperature and pressure and in the presence of hydrogen in an upward, downward or radial direction, and the reactor contains a fixed bed or moving bed of hydrotreatment catalyst particles. In one embodiment, the hydrogen used for the hydrotreatment reaction can be produced, for example but not limited to, by water electrolysis. The water electrolysis process can be powered by renewable energy sources such as solar photovoltaic, wind power or hydroelectric power to generate green hydrogen, nuclear energy, or by non-renewable energy sources (gray hydrogen) from other sources. Hydrotreatment can be carried out in a silo flow reactor, a fixed bed reactor, a fixed bed swing reactor or a moving bed reactor. Preferably, the hydrotreatment in step (d) is carried out in two reaction zones, whereby the hydrodemetallized product is first passed into the first reaction zone, wherein the hydrodemetallized product is partially hydrotreated, and then the partially hydrotreated effluent thus obtained is subjected to further hydrotreatment in the second reaction zone. The first reaction zone and the second reaction zone can be arranged in a stacked bed configuration, or the two reaction zones can be arranged in separate reactors. Preferably, the first reaction zone and the second reaction zone are arranged in the first reactor and the second reactor, respectively. The first reactor can be a silo flow reactor, and the second reactor can be a fixed bed reactor.

[0036] The hydrotreating catalyst used in step (d) may be suitably a desulfurization catalyst. The desulfurization catalyst may be any hydrodesulfurization catalyst known in the art. Suitable hydrodesulfurization catalysts include compounds of metals of Group VIII of the Periodic Table and metals of Group VIB of the Periodic Table as hydrogenation components on a porous catalyst carrier (typically alumina or amorphous silica-alumina). Examples of suitable combinations of well-known hydrogenation compounds are cobalt-molybdenum, nickel-molybdenum, nickel-tungsten and nickel-cobalt-molybdenum. Preferably, compounds comprising nickel and / or cobalt and molybdenum are used as hydrodesulfurization catalysts for hydrogenation compounds. The hydrodesulfurization catalyst may also include cracking components, such as, for example, Y zeolite. However, it is preferred that substantial hydrocracking does not occur in the hydrotreating of step (d). Therefore, it is preferred that the catalyst is substantially free of cracking components. Particularly preferred are catalysts comprising nickel and / or cobalt and molybdenum supported on alumina without zeolite cracking compounds.

[0037] The hydroprocessing conditions in step (d), i.e., temperature, pressure, hydrogen supply rate, weight hourly space velocity of the feedstock, are typical hydroprocessing conditions. Preferably, the temperature for hydroprocessing in step (c) is in the range of 280°C to 430°C, more preferably in the range of 320°C to 420°C, most preferably in the range of 330°C to 410°C.

[0038] Suitable hydrotreating pressures are in the range of 10 bara to 300 bara. Preferably, the hydrotreating pressure is in the range of 30 bara to 250 bara, more preferably in the range of 80 bara to 220 bara.

[0039] In step (e), at least a portion of the hydroprocessed product obtained in step (d) is hydrocracked to obtain a hydrocracked product. Preferably, in step (e), all of the hydroprocessed product obtained in step (d) is hydrocracked.

[0040] The hydrocracking in step (e) of the method according to the present invention can be carried out in any manner known in the art, as long as at least one of the catalysts used in the hydrocracking zone is acidic. Suitably, the hydrocracking is carried out at elevated temperature and pressure in the presence of hydrogen and a suitable hydrocracking catalyst. In one embodiment, the hydrogen used for the hydrocracking reaction can be produced, for example but not limited to, by water electrolysis. The water electrolysis process can be powered by renewable energy sources (such as solar photovoltaic, wind or hydroelectric power) to generate green hydrogen, nuclear energy, or powered by non-renewable energy sources (gray hydrogen) from other sources. Suitable hydrocracking catalysts are composed of metals from nickel, tungsten, cobalt and molybdenum in the form of one or more elements, oxides or sulfides on suitable carriers (such as alumina, silica, silica-alumina or zeolite). Many commercially available hydrocracking catalysts can be appropriately applied to the method of the present invention. At least one of the catalysts used in the hydrocracking zone must be acidic, that is, it must contain silica-alumina and / or zeolite components.

[0041] The hydrocracking in step (e) can be carried out in a single-stage or multi-stage operation mode. In the case of a single-stage operation mode, a stacked bed of hydrodenitrogenation / first-stage hydrocracking catalyst on top of a conversion catalyst can be suitably used. Particularly suitable hydrodenitrogenation / first-stage hydrocracking catalysts are NiMo / Al2O3 and CoMo / Al2O3, optionally promoted with phosphorus and / or fluorine. Preferred conversion catalysts are those based on NiW / zeolite or NiW / zeolite / silica-alumina. Suitable hydrocracking conditions in step (e) are: an operating pressure of 80 bara to 250 bara, preferably 90 bara to 220 bara, and a temperature of 300°C to 460°C, preferably 350°C to 430°C.

[0042] Without being bound by theory, it has been surprisingly found that by introducing a hydrogen-depleted feed as part of the mixed deasphalted product, the activity of the catalyst in the hydrodemetallization reactor is increased only. For example, in a simulation where slurry oil (SLO) was added to deasphalted oil (DAO) to form a mixed DAO feed, the average hydrogen content of the DAO feed was reduced by 0.3 wt%, the heat release rate on the hydrodemetallization catalyst increased by 20%, while the heat release rate on the subsequent hydrotreating and hydrocracking catalysts remained almost constant. The increase in the activity of the hydrodemetallization catalyst allows a reduction in the inlet temperature of the (first) hydrodemetallization reactor, which can reduce the load of the reactor feed furnace to the hydrodemetallization reactor, which in turn can be used to increase the cycle length of the unit.

[0043] In step (f), at least a portion of the hydrocracked product obtained in step (e) is subjected to a separation treatment to obtain at least one middle distillate fraction. Preferably, in step (f), all of the hydrocracked product obtained in step (e) is subjected to a separation treatment.

[0044] The separation treatment in step (f) may suitably be a fractionation treatment carried out at a temperature in the range of 50°C to 400°C, preferably in the range of 70°C to 370°C, and at a pressure in the range of 0.03 bara to 15 bara, preferably in the range of 0.05 bara to 10 bara.

[0045] A fuel gas fraction can also be obtained from step (f), preferably containing C1-C2 products. In other embodiments, the fuel gas fraction may include C1-C4 products. In some embodiments, if a renewable hydrogen-depleted feed is used in step (b), at least a portion of the fuel gas fraction will have a renewable source. Therefore, if a fuel gas with a renewable source is used in hydrogen production, a portion of the produced hydrogen can be considered to have a renewable source.

[0046] In addition to the middle distillate fraction to be obtained in step (f), a heavy residual fraction may also be obtained. Suitably, at least 80% by weight of the heavy residual fraction also obtained in the separation process of step (f) has a boiling point above 370° C. Preferably, at least 90% of the heavy residual fraction also obtained in the separation process of step (f) has a boiling point above 370° C.

[0047] At least part of the heavy residual fraction obtained in step (f) can also be recycled into step (a). In this way, an increased yield of the middle distillate can be obtained.

[0048] Alternatively, the heavy fraction may also be suitably used as feed to a fluid catalytic cracking (FCC) unit or as feedstock for lubricant oil manufacture.Of course, combinations of these options are also possible.

[0049] In order to obtain the best middle distillate yield, it is preferred to subject at least a portion of the heavy fraction obtained in step (f) to hydrocracking again to increase the yield of the middle distillate. Therefore, in a preferred embodiment, at least a portion of the heavy residual fraction also obtained in step (f) is recycled to step (e).

[0050] In another preferred embodiment of the present invention, at least a portion of the heavy residual fraction also obtained in step (f) is recycled to step (a), and at least a portion of the heavy residual fraction also obtained in step (f) is recycled to step (e). In this way, the yield of the middle distillate is further increased.

[0051] In yet another preferred embodiment, at least a portion of the heavy residual fraction obtained in step (f) is likewise subjected to a further hydrocracking step (g), and at least a portion of the hydrocracked product obtained in this step (g) is recycled to step (f). Furthermore, this embodiment will ensure that an optimal yield of the middle distillate is established.

[0052] Preferably, at least a portion of the heavy residual fraction also obtained in step (f) is also recycled to step (a) in order to increase the middle distillate yield even further.

[0053] Preferably, the hydrocracking in step (e) and / or step (g) is carried out in two or more reaction zones. Preferably, the two or more reaction zones are arranged in a stacked bed configuration.

[0054] Preferably, at least a portion of the bitumen product obtained in step (a) is subjected to a gasification step (h) to obtain hydrogen and carbon monoxide. In some embodiments, the bitumen product obtained in step (a) will have a portion of renewable origin if a renewable hydrogen-depleted feed is used in step (b) and at least a portion of the heavy residual fraction also obtained in step (f) is recycled to step (a).

[0055] The asphalt product obtained in step (a) can be used in a variety of ways. For example, it can be burned for cogeneration of electricity and steam. Alternatively, it can be partially burned for clean fuel gas production, cogeneration of electricity and steam, hydrogen production or hydrocarbon synthesis. In another embodiment, if the asphalt has a part of a renewable source, the hydrogen produced by it will be considered as a part of a green source. Another option is to be applied to asphalt, emulsified fuel or solid fuel by granulation.

[0056] Preferably, such gasification step (h) is a partial combustion step.

[0057] In a preferred embodiment, at least a portion of the hydrogen obtained in step (h) is recycled to at least one of step (c), step (d), step (e) and step (g).

[0058] The middle distillate fraction obtained in step (f) comprises a middle distillate containing less than 10 ppmwt of sulfur. Preferably, the middle distillate contains less than 8 ppmwt of sulfur, more preferably less than 6 ppmwt of sulfur, and most preferably less than 5 ppmwt of sulfur.

[0059] Figure 1 A method according to the present invention is shown; Figure 2 Another embodiment of the present invention is shown; and Figure 3 Another embodiment of the method of the present invention is shown.

[0060] exist Figure 1 In the process, atmospheric or vacuum hydrocarbon oil residue is passed through pipeline 1 to a deasphalting unit 2, in which a deasphalted product and an asphalt product are obtained. A hydrogen-depleted feed is fed through pipeline 20 to be mixed with at least a portion of the deasphalted product in pipeline 3 to form a mixed deasphalted product. At least a portion of the mixed deasphalted product is passed to a hydrodemetallization unit 5, and an asphalt product is taken out of the deasphalting unit 2 through pipeline 4. At least a portion of the hydrodemetallization product obtained in the hydrodemetallization unit 5 is passed through a pipeline 6 to a hydroprocessing unit 7. Then, at least a portion of the hydroprocessed product obtained in the hydroprocessing unit 7 is passed through a pipeline 8 to a hydrocracking unit 9. At least a portion of the hydrocracking product obtained in the hydrocracking unit 9 is passed through a pipeline 10 to a fractionation unit 11, from which at least one middle distillate fraction is recovered through a pipeline 12.

[0061] Figure 2 yes Figure 1 An extension of the deasphalting unit 2, wherein a heavy residual fraction is also obtained in the fractionation unit 11, which is taken off from the fractionation unit 11 via a pipeline 13 and at least a part of which is recycled to the deasphalting unit 2.

[0062] Figure 3 yes Figure 2An expansion of, wherein a heavy residual fraction is also obtained in the fractionation unit 11, the heavy residual fraction is taken out from the fractionation unit 11 via a pipeline 13, and at least a portion of the heavy residual fraction is recycled to the hydrocracking unit 9 via a pipeline 14, and / or at least a portion of the heavy residual fraction is recycled to the hydrodemetallization unit 5 via a pipeline 15, and / or at least a portion of the heavy residual fraction is recycled to the deasphalting unit 2 via a pipeline 16.

[0063] Figure 4 yes Figure 1 The invention relates to an expansion of the present invention, wherein a heavy residual fraction is also obtained in the fractionation unit 11, the heavy residual fraction is taken out from the fractionation unit 11 via a pipeline 13, and at least a part of the heavy residual fraction is passed to a hydrocracking unit 17 via a pipeline 13, from which at least one fraction fraction is recovered via a pipeline 21. At least a part of the hydrocracking product obtained in the hydrocracking unit 14 is recycled to the fractionation unit 11 via pipelines 18 and 19, and at least a part of the heavy residual fraction obtained in the fractionation unit 11 is recycled to the deasphalting unit 2 via pipelines 18 and 20.

[0064] Although several embodiments of the present disclosure have been described in detail above, it will be readily appreciated by those skilled in the art that many modifications may be made without departing substantially from the teachings of the present disclosure. Therefore, such modifications are intended to be included within the scope of the present disclosure as defined by the claims.

Claims

1. A process for producing a middle distillate from a feedstock comprising a residual hydrocarbonaceous feedstock and a hydrogen-depleted feedstock, the process comprising the steps of: (a) deasphalting the residual hydrocarbonaceous feedstock to obtain a deasphalted product and an asphalt product wherein at least 50% by weight of the deasphalted product has a boiling point above 550° C.; (b) mixing the deasphalted product with the hydrogen-depleted feedstock to produce a mixed deasphalted product, wherein the hydrogen-depleted feedstock has a hydrogen (H) content of at least 6 wt % and at most 11.3 wt %; (c) hydrodemetallizing at least a portion of the mixed deasphalted product from step (b) to produce a hydrodemetallized product; (d) hydroprocessing at least a portion of the hydrodemetallized product from step (c) to produce a hydroprocessed product; (e) hydrocracking at least a portion of the hydrotreated product from step (d) to produce a hydrocracked product; as well as (f) subjecting at least a portion of said hydrocracked product from step (e) to a separation treatment to produce at least one middle distillate fraction.

2. The process of claim 1 wherein the amount of the hydrogen-depleted feedstock comprises up to about 50 weight percent of the mixed deasphalted product.

3. The method of claim 1, wherein via the addition of the hydrogen-depleted feedstock, the hydrogen content of the mixed deasphalted product is less than at least 0.1 wt. % of the deasphalted product.

4. The method of any one of claims 1 to 3, wherein at least a portion of the hydrogen-depleted feedstock comprises a portion of a renewable source.

5. The process according to any one of claims 1 to 3, wherein the hydrogen-depleted feedstock comprises slurry oil from a fluid catalytic cracker (FCC) unit.

6. The process of claim 4, wherein the hydrogen-depleted feedstock comprises tall oil pitch from crude tall oil distillation.

7. The process according to any one of claims 1 to 5, wherein the middle distillate fraction produced in step (f) contains less than 10 ppmwt of sulfur.

8. The process according to any one of claims 1 to 6, wherein the separation treatment in step (f) produces a heavy residual fraction wherein 80% by weight of the heavy residual fraction has a boiling point above 370°C.

9. The method according to any one of claims 4, wherein a fuel gas fraction having a portion of renewable origin is also produced in the separation process in step (f).

10. Process according to claim 4, wherein at least a portion of the bitumen product obtained in step (a) is subjected to a gasification step (h) to obtain hydrogen and carbon monoxide having a portion of renewable origin.

Images