CN117651754A

CN117651754A - Slurry bed hydroconversion of a heavy hydrocarbon feedstock comprising said feedstock mixed with a catalyst precursor comprising an organic additive

Info

Publication number: CN117651754A
Application number: CN202280048472.7A
Authority: CN
Inventors: J·马克斯; T·科雷; J·巴比耶; B·M·西尔弗曼; D·M·蒙塔因兰德; S·帕拉舍尔
Original assignee: IFP Energies Nouvelles IFPEN
Current assignee: IFP Energies Nouvelles IFPEN
Priority date: 2021-07-08
Filing date: 2022-06-27
Publication date: 2024-03-05
Also published as: WO2023280627A1; FR3125060A1

Abstract

The present invention relates to a slurry hydroconversion process of a heavy oil feedstock (101), comprising: (a) Preparing a conditioned feedstock (103) by mixing the feedstock with a catalyst precursor formulation (104), such that the catalyst precursor formulation (104) forms a colloidal or molecular catalyst when reacted with sulfur, the catalyst precursor formulation (104) comprising a catalyst precursor composition (105) comprising Mo, an organic additive (102) comprising carboxylic acid functionality and/or ester functionality and/or anhydride functionality, and the molar ratio of organic additive (102)/Mo from formulation (104) being from 0.1:1 to 20:1; (b) heating the conditioned feedstock; (c) The heated conditioned feedstock (106) is introduced into at least one slurry bed reactor and the reactor is operated in the presence of hydrogen and hydroconversion conditions to produce a upgraded material (107), a colloidal or molecular catalyst being formed during step (b) and/or step (c).

Description

Slurry bed hydroconversion of a heavy hydrocarbon feedstock comprising said feedstock mixed with a catalyst precursor comprising an organic additive

Technical Field

The present invention relates to a process for converting heavy oil feedstock in the presence of hydrogen, a colloidal or molecular catalyst and an organic additive.

In particular, the present invention relates to a process for hydroconversion of a heavy oil feedstock comprising at least 50% by weight of a fraction having a boiling point of at least 300 ℃, and in particular a heavy oil feedstock comprising a substantial amount of asphaltenes and/or fractions having a boiling point higher than 500 ℃, such as crude oil or heavy hydrocarbon fractions resulting from atmospheric and/or vacuum distillation of crude oil, to obtain a lower boiling point, higher quality material.

The process particularly includes mixing the heavy oil feedstock with a catalyst precursor formulation comprising organic additives prior to feeding the heavy oil feedstock into one or several slurry bed reactors in order to upgrade such low quality feedstock prior to hydroconversion in the one or several slurry bed reactors while minimizing fouling in the plant by inhibiting coke precursor and sediment formation.

Prior Art

Conversion of heavy oil feedstock into useful end products requires extensive treatment including lowering the boiling point of the heavy oil, increasing the hydrogen to carbon ratio, and removing impurities such as metals, sulfur, nitrogen, and high carbon content compounds.

Catalytic hydroconversion is commonly used for heavy oil feedstocks and is typically performed using a three-phase reactor in which the feedstock is contacted with hydrogen and a catalyst. In the reactor, the catalyst may be used in the form of a fixed bed, moving bed, ebullated bed or entrained bed, for example as described in "Heavy Crude Oils: from Geology to Upgrading An Overview "book (2011 byChapter 18 of the Technip publication), "Catalytic Hydrotreatment and Hydroconversion: fixed Bed, moving Bed, ebullated Bed and Entrained Bed ". In the case of ebullated or entrained beds, the reactor includes an ascending flow of liquid and gas. The choice of technique generally depends on the nature of the feedstock to be treated, in particular its metal content, its tolerance to impurities and the target conversion.

Slurry bed hydroconversion processes employ entrained bed technology, also known as slurry bed technology. In such a process, a dispersed catalyst or catalyst precursor is continuously injected into a heavy oil feedstock in a slurry reactor, promoting hydrogenation of free radicals formed by thermal cracking reactions and limiting coke formation. The catalyst not only provides catalytic activity, but also provides a surface for deposition of metals and asphaltenes from the feedstock. Since the catalyst and liquid heavy oil feedstock appear homogeneous, catalyst dispersed in the feedstock with very small size is entrained out of the reactor with the effluent.

Known slurry bed hydroconversion processes are generally aimed at completely converting heavy oil feedstocks into lighter fractions using highly severe operating conditions (temperature, hydrogen partial pressure, residence time). The theoretical advantage of slurry bed processes is that the hydrogenation is much better, especially for the heaviest products, due to better accessibility of the active sites, resulting in higher conversion, improved product quality and higher product stability. In addition, catalyst deactivation is greatly reduced due to the shorter catalyst residence time. Regarding product stability, it is known that during operation of slurry bed reactors for upgrading heavy oils, the heavy oils are heated to a temperature at which high boiling fractions (examples of which are a class of complex compounds collectively referred to as "asphaltenes") in the heavy oil feedstock, typically having a high molecular weight and/or a low hydrogen to carbon ratio, tend to thermally crack to form reduced chain length free radicals. These radicals may react with other radicals or with other molecules to form coke precursors and deposits. The slurry catalyst flowing through the reactor reacts with the free radicals in these regions to form stable molecules of reduced molecular weight and boiling point, thereby helping to control and reduce the formation of deposits and coke precursors. Since coke and sediment formation are the primary cause of fouling of hydroconversion equipment, such slurry processes can prevent fouling of downstream equipment such as separation vessels, distillation columns, heat exchangers, and the like.

Slurry catalysts for hydroconversion of heavy oils, in particular colloidal or molecular catalysts formed by using soluble catalytic precursors, are well known in the art. It is particularly known that certain metal compounds, such as organic soluble compounds (e.g. molybdenum naphthenate or molybdenum octoate as cited in US4244839, US 2005/024781, US 2014/0027344) or water soluble compounds (e.g. phosphomolybdic acid as cited in patents US3231488, US4637870 and US 4637871; ammonium heptamolybdate as cited in patent US 6043182; heteropolyanion salts as cited in FR 3074699) can be used as dispersion catalyst precursors and form catalysts. In the case of water-soluble compounds, the dispersed catalyst precursor is typically mixed with the starting materials to form an emulsion. Dispersing the catalyst (typically molybdenum) precursor (optionally in an acidic medium (in H ₃ PO ₄ In the presence of (2) or an alkaline medium (in NH) ₄ In the presence of OH) promoted by cobalt or nickel) has been the subject of many studies and patents.

Patent document US8431016 discloses a process for hydroconversion of heavy oils using colloidal or molecular catalysts in slurry bed hydrocracking reactors. The dispersed organic soluble catalyst precursor is pre-diluted in Vacuum Gas Oil (VGO) prior to introduction into the slurry bed reactor and then added in a stage of intimately mixing with the feedstock to produce a conditioned feedstock. The catalyst precursor is typically molybdenum 2-ethylhexanoate, which, once heated, reacts with H produced by hydrodesulfurization of the feedstock ₂ S reacts to form a colloidal or molecular catalyst (e.g., dispersed molybdenum sulfide). Such a process inhibits coke precursor and deposit formation that might otherwise foul ebullated bed reactors and downstream equipment while providing substantially the same conversion of asphaltene fractions as the overall residuum conversion, even at very high overall residuum conversion, unlike hydroconversion processes using conventional supported catalysts.

In addition to the fouling that occurs in slurry bed reactors and downstream equipment due to coke precursors and deposits, the inventors have observed that fouling also occurs in upstream equipment as long as the heavy oil feedstock containing catalyst precursors is heated prior to entering the hydroconversion reactor.

In equipment upstream of the hydroconversion reactor, particularly in heating equipment of heavy oil feedstock mixed with catalyst precursors of specific colloidal or molecular catalysts, such fouling appears to be mainly related to metal and carbon accumulation on the walls and may limit the operability of the equipment.

Thus, while slurry catalysts in known slurry processes (such as the process described in document US 8431016) are known to reduce fouling in hydroconversion reactors and downstream equipment due to coke precursors and deposits, fouling observed in upstream equipment (e.g., preheating equipment) containing heavy oil feedstock mixed with catalyst precursors is another operational problem not heretofore addressed. Furthermore, it was observed that in some cases fouling due to coke precursors and deposits still occurred in downstream equipment, indicating that the addition performance of the slurry catalyst remains to be improved.

Object and summary of the invention

In view of the above background, it is an object of the present invention to provide a slurry hydroconversion process which solves the problem of fouling, in particular in equipment upstream of the hydroconversion reactor, and especially in feed preheating equipment prior to conversion of the feed in one or more slurry hydroconversion reactors, with a colloidal or molecular catalyst formed by the use of soluble catalytic precursors.

More specifically, the present invention aims to provide a slurry hydroconversion process for upgrading a heavy oil feedstock, said process having one or more of the following effects: the method reduces equipment scaling, more effectively treats asphaltene molecules, reduces the formation of coke precursors and sediments, improves the conversion rate level, enables a reactor to treat lower-quality raw materials with wider range, eliminates a catalyst-free zone in downstream treatment equipment, prolongs the running time between shutdown maintenance, improves the throughput of heavy oil raw materials, and improves the production rate of conversion products. Reducing the frequency of closing and starting up the process vessel means reducing the pressure and temperature cycling of the process equipment, which greatly improves process safety and prolongs the life of expensive equipment.

Thus, in order to achieve at least one of the above objects, according to a first aspect, the present invention provides a process for hydroconversion of a heavy oil feedstock comprising at least 50 wt.% of a fraction having a boiling point of at least 300 ℃ and comprising metals and asphaltenes, the process comprising the steps of:

(a) Preparing a conditioned heavy oil feedstock by mixing the heavy oil feedstock with a catalyst precursor formulation by such a way that a colloidal or molecular catalyst is formed when the catalyst precursor formulation reacts with sulfur, the catalyst precursor formulation comprising:

catalyst precursor composition comprising molybdenum, and

an organic compound comprising at least one carboxylic acid function and/or at least one ester function and/or anhydride function, and

-the molar ratio between the organic compound and molybdenum in the catalyst precursor formulation is between 0.1:1 and 20:1;

(b) Heating the conditioned heavy oil feedstock from step (a) in at least one preheating device;

(c) Introducing the heated conditioned heavy oil feedstock from step (b) into at least one slurry bed reactor and operating the slurry bed reactor in the presence of hydrogen and hydroconversion conditions to produce a upgraded material; and wherein

The colloidal or molecular catalyst is formed in situ within the conditioned heavy oil feedstock in step (b) and/or step (c).

According to one or more embodiments, step (a) comprises mixing the organic compound with the catalyst precursor composition (which is preferably diluted with a hydrocarbon oil diluent beforehand) and the heavy oil feedstock simultaneously, preferably at a temperature below which most of the catalyst precursor composition starts to thermally decompose, for example at a temperature of from room temperature to 300 ℃ for a period of from 1 second to 30 minutes.

According to one or more embodiments, step (a) comprises: (a1) Premixing the organic compound with the catalyst precursor composition to produce the catalyst precursor formulation and (a 2) mixing the catalyst precursor formulation with the heavy oil feedstock.

According to one or more embodiments, in step (a 1), the catalyst precursor composition is mixed at a temperature below the temperature at which most of the catalyst precursor composition starts to thermally decompose, preferably at a temperature of from room temperature to 300 ℃.

According to one or more embodiments, the catalyst precursor formulation is formed using a hydrocarbon oil diluent, preferably selected from the group consisting of vacuum gas oil, decant oil or cycle oil, light gas oil, vacuum residuum, deasphalted oil, and resins.

According to one or more embodiments, the organic compound is selected from the group consisting of ethyl hexanoic acid, naphthenic acid, octanoic acid, adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid, ethyl octanoate, ethyl 2-ethylhexanoate, 2-ethylhexyl 2-ethylhexanoate, benzyl 2-ethylhexanoate, diethyl adipate, dimethyl adipate, di (2-ethylhexyl) adipate, dimethyl pimelic acid, dimethyl suberate, monomethyl suberate, hexanoic anhydride, octanoic anhydride, and mixtures thereof.

According to one or more embodiments, the organic compound comprises 2-ethylhexanoic acid, preferably 2-ethylhexanoic acid.

According to one or more embodiments, the organic compound comprises ethyl octanoate or 2-ethylhexyl 2-ethylhexanoate, preferably ethyl octanoate or 2-ethylhexyl 2-ethylhexanoate.

According to one or more embodiments, the catalyst precursor composition comprises an oil-soluble organometallic compound or complex selected from molybdenum 2-ethylhexanoate, molybdenum naphthenate, molybdenum hexacarbonyl, preferably molybdenum 2-ethylhexanoate.

According to one or more embodiments, the molar ratio between the organic compound and molybdenum of the catalyst precursor formulation is from 0.75:1 to 7:1, preferably from 1:1 to 5:1.

According to one or more embodiments, the colloidal or molecular catalyst comprises molybdenum disulfide.

According to one or more embodiments, step (b) comprises heating at a temperature of 280 ℃ to 450 ℃, more preferably 300 ℃ to 400 ℃, most preferably 320 ℃ to 365 ℃.

According to one or more embodiments, the heavy oil feedstock comprises at least one of the following: heavy crude oil, oil sand bitumen, atmospheric bottoms, vacuum bottoms, residuum, visbreaker bottoms, coal tar, heavy oils from oil shale, liquefied coal, heavy bio-oils, and heavy oils comprising plastic waste and/or plastic pyrolysis oil.

According to one or more embodiments, the heavy oil feedstock has a sulfur content of greater than 0.5 wt%, a Conradson carbon residue of at least 0.5 wt%, a C of greater than 1 wt% ₇ Asphaltene content, transition metal and/or post-transition metal and/or metalloid content of greater than 2 ppm by weight, and alkali metal and/or alkaline earth metal content of greater than 2 ppm by weight.

According to one or more embodiments, at an absolute pressure of 2MPa to 38MPa, at a temperature of 300℃to 550℃for 0.05h ^-1 For 10h ^-1 At a liquid hourly space velocity, LHSV, relative to the volume of each slurry bed reactor and at a time per m ³ 50-5000Nm of raw material ³ Step (c) is carried out with an amount of hydrogen mixed with the feedstock entering the slurry bed reactor.

According to one or more embodiments, the concentration of molybdenum in the conditioned oil feedstock is preferably from 10 ppm by weight to 10000 ppm by weight of the heavy oil feedstock.

Other subjects and advantages of the present invention will become apparent upon reading the following description of specific exemplary embodiments thereof, given by way of non-limiting example and with reference to the accompanying drawings described below.

Drawings

FIG. 1 is a block diagram illustrating the principles of a slurry bed hydroconversion process in accordance with the present invention.

Fig. 2 is a block diagram illustrating a slurry bed hydroconversion process in which a catalyst precursor formulation is obtained by premixing an organic additive with a catalyst precursor composition in accordance with one embodiment of the present invention.

FIG. 3 is a block diagram illustrating one example of slurry bed hydroconversion shown in FIG. 2, wherein a catalyst precursor formulation is obtained by mixing a catalyst precursor composition with an organic additive comprising a diluent.

FIG. 4 is a block diagram illustrating another example of slurry bed hydroconversion shown in FIG. 2, wherein a catalyst precursor formulation is obtained by mixing a catalyst precursor composition containing an additive with a hydrocarbon oil diluent.

Fig. 5 is a block diagram illustrating another example of slurry bed hydroconversion shown in fig. 2, wherein a catalyst precursor formulation is obtained by mixing a diluted catalyst precursor composition with an organic additive.

FIG. 6 is a block diagram illustrating an example of a slurry bed hydroconversion process and system in accordance with the present invention.

Fig. 7 is a graph showing the fouling propensity of an example of a prepared conditioned oil feedstock in a slurry bed hydroconversion process in accordance with the present invention and in accordance with the prior art.

Description of the embodiments

It is an object of the present invention to provide a slurry bed hydroconversion process and system for improving the quality of a heavy oil feedstock.

Such a process and system for hydroconversion of a heavy oil feedstock employs a slurry catalyst, which is a molecular or colloidal catalyst dispersed within the heavy oil feedstock. They also employ organic additives added to the catalyst precursor formulation mixed with the heavy oil feedstock prior to operating the slurry catalyst in one or more slurry bed reactors, each reactor comprising a liquid phase comprising the heavy oil feedstock, the colloidal or molecular catalyst dispersed therein, and the organic additive, and a gas phase comprising hydrogen.

The slurry bed hydroconversion processes and systems of the present invention reduce equipment fouling, particularly in equipment upstream of one or more hydroconversion reactors, particularly in feed preheating equipment prior to conversion of feed in one or more slurry hydroconversion reactors, and can effectively treat asphaltenes, reduce or eliminate coke precursor and deposit formation, increase conversion levels, particularly by allowing hydroconversion operations to be conducted at high temperatures, and eliminate catalyst-free zones that would otherwise be present in downstream processing equipment.

Terminology

Some definitions are given below, but more details of the objects defined below will be given further in the description.

The term "hydroconversion" refers to a process whose primary purpose is to reduce the boiling range of a heavy oil feedstock and to convert a substantial portion of the feedstock to products having a boiling range lower than that of the starting feedstock. Hydroconversion generally involves splitting larger hydrocarbon molecules into smaller molecular fragments having a lower number of carbon atoms and a higher hydrogen to carbon ratio. Reactions carried out during hydroconversion may reduce the size of hydrocarbon molecules, mainly by breaking carbon-carbon bonds in the presence of hydrogen, thereby saturating the broken bonds and aromatic rings. The mechanism by which hydroconversion occurs typically involves the formation of hydrocarbon radicals during cleavage, primarily by thermal cracking, followed by termination or partial termination of the radicals with hydrogen in the presence of active catalyst sites. Of course, other reactions typically associated with "hydrotreating" can also occur during hydroconversion, such as removal of sulfur and nitrogen from the feedstock and olefin saturation.

According to the english term "hydrocracking" is generally used as synonym for "hydroconversion", although "hydrocracking" refers to a process similar to hydroconversion, but in which the cracking of the hydrocarbon molecules is mainly catalytic cracking, i.e. occurs in the presence of a hydrocracking catalyst having a phase responsible for the cracking activity, for example acid sites, such as those contained in clays or zeolites. Hydrocracking, which may be translated as "hydrocraquate", for example, according to french terminology, generally refers to this latter definition (catalytic cracking), the use of which is biased, for example, towards the use of vacuum distillates as the oil feedstock to be converted, whereas french terminology "hydroconversion" is generally biased towards the conversion of heavy oil feedstocks such as, but not limited to, atmospheric and vacuum residues.

The term "hydrotreating" shall refer to a milder operation whose primary purpose is to remove impurities, such as sulfur, nitrogen, oxygen, halides and trace metals, from a feedstock by reacting it with hydrogen and saturate olefins and/or stabilize hydrocarbon radicals, rather than allowing them to react with themselves. Its main purpose is not to change the boiling range of the feed. Hydroprocessing is most commonly performed using fixed bed reactors, but other hydroprocessing (hydroprocessing) reactors may also be used, such as ebullated bed hydroprocessing reactors.

The term "hydroprocessing" refers broadly to both "hydroconversion"/"hydrocracking" and "hydrotreating" processes.

The term "hydroconversion reactor" shall refer to any vessel in which hydroconversion of the feedstock is the primary purpose, e.g. cracking (i.e. reducing the boiling range) of the feedstock in the presence of hydrogen and a hydroconversion catalyst. The hydroconversion reactor typically includes an inlet into which the heavy oil feedstock and hydrogen gas can be introduced, and an outlet from which the upgraded material can be withdrawn. In particular, hydroconversion reactors are also characterized by having sufficient thermal energy to break up larger hydrocarbon molecules into smaller molecules by thermal decomposition. Examples of hydroconversion reactors, particularly hydrocracking reactors, include, but are not limited to, slurry bed reactors, also known as entrained bed reactors (three-phase one-liquid, gas, solid reactors, where the solid and liquid phases behave like homogeneous), ebullated bed reactors (three-phase fluidized reactors), moving bed reactors (three-phase reactors, where the solid catalyst moves downward, liquid and gas flow upward or downward), and fixed bed reactors (three-phase reactors, where the liquid feed trickles downward over a fixed bed of solid supported catalyst, with hydrogen generally flowing with the liquid and in a countercurrent direction, but in some cases may be reversed).

For hydroconversion reactors, the terms "mixed bed", "mixed ebullated bed" and "mixed entrainment-ebullated bed" refer to ebullated bed hydroconversion reactors that contain entrained catalyst in addition to the porous supported catalyst maintained in the ebullated bed reactor. Similarly, for a hydroconversion process, these terms shall thus refer to a process comprising a mixed operation of ebullated and entrained beds in at least the same hydroconversion reactor. A mixed bed is a mixed bed of two types of catalysts, necessarily of different particle size and/or density, one type of catalyst-a "porous supported catalyst" being held in the reactor, while the other type of catalyst-an "entrained catalyst", also commonly referred to as "slurry catalyst" -is entrained out of the reactor with the effluent (upgraded feedstock). In the present invention, the entrained catalyst is a colloidal catalyst or a molecular catalyst as defined below.

The terms "slurry bed reactor", "slurry phase reactor" and "slurry reactor" shall refer broadly to two-phase (i.e., liquid and gas) or three-phase (i.e., liquid, gas and solid) slurry bed reactors for the hydroconversion, particularly hydrocracking, of heavy oil feedstock. In the present invention, it shall mean a slurry reactor comprising at least a colloidal or molecular catalyst as defined below. In the present invention, the slurry bed reactor comprises a slurry catalyst, which is at least a colloidal catalyst or a molecular catalyst as defined below, which is the only hydroconversion catalyst within the slurry bed reactor (without a porous supported catalyst that remains in the reactor during operation as in ebullated or mixed bed reactors). An exemplary slurry bed reactor is disclosed in US 6960325B. The liquid phase typically comprises a hydrocarbon feedstock containing a colloidal catalyst or a molecular-sized catalyst (solid particles). Due to the catalyst particle size (colloid or molecule), the solid catalyst particles of colloid or molecule size may appear as a continuous liquid phase with the liquid hydrocarbon feedstock. Solid catalysts in the form of solid particles of micron size or larger may also be used with liquids and gases.

The terms "colloidal catalyst" and "colloidal dispersion catalyst" shall refer to catalyst particles having a colloidal size particle size, e.g. a size (diameter) of less than 1 μm, preferably a size of less than 500nm, more preferably a size of less than 250nm, or a size of less than 100nm, or a size of less than 50nm, or a size of less than 25nm, or a size of less than 10nm, or a size of less than 5nm. The term "colloidal catalyst" includes, but is not limited to, a molecular or molecular dispersed catalyst compound.

The terms "molecular catalyst" and "molecular dispersion catalyst" shall refer to catalyst compounds that are substantially "dissolved" or completely dissociated from other catalyst compounds or molecules in the heavy oil hydrocarbon feedstock, non-volatile liquid fraction, bottoms fraction, resid, or other feedstock or product in which the catalyst is present. It also refers to very small catalyst particles or platelets (slibs) that contain only a few catalyst molecules (e.g., 15 molecules or less) linked together.

The terms "porous supported catalyst", "solid supported catalyst" and "supported catalyst" shall refer to catalysts commonly used in conventional ebullated bed and fixed bed hydroconversion systems, including catalysts designed primarily for hydrocracking or hydrodemetallization and catalysts designed primarily for hydrotreating. Such catalysts typically comprise: (i) A catalyst support having a large surface area and a plurality of interconnected channels or pores, and (ii) active catalyst fines, such as cobalt, nickel, tungsten and/or molybdenum sulfides, dispersed in the pores. The supported catalyst is typically produced in the form of cylindrical pellets or spherical solids, but may be of other shapes.

The terms "upgraded" and "upgraded" when used to describe a feedstock that is or has been hydroconverted, or a material or product produced therefrom, shall refer to one of the following: a reduction in feedstock molecular weight, a reduction in feedstock boiling range, a reduction in asphaltene concentration, a reduction in hydrocarbon radical concentration, a reduction in Conradson carbon residue, an increase in the H/C atomic ratio of the feedstock, and a reduction in the amount of impurities (e.g., sulfur, nitrogen, oxygen, and halides).

The terms "conditioned feedstock" and "conditioned heavy oil feedstock" shall refer to a heavy oil feedstock to be treated in at least one hydroconversion slurry bed reactor having in the feedstock a catalyst precursor formulation comprising a catalyst precursor composition and an organic additive which have been sufficiently combined and mixed such that when the catalyst is formed, in particular by reaction with sulfur, the catalyst will comprise a colloidal or molecular catalyst dispersed within the feedstock.

The term "active mixing device" shall mean a mixing device comprising moving parts (e.g. stirring bars, propellers or turbine wheels) for actively mixing components.

Hereinafter, the term "comprising" is synonymous (meaning identical) with "comprising" and "containing" and is inclusive or open ended and does not exclude additional unspecified elements. It is to be understood that the term "comprising" includes the exclusive closed term "consisting of.

The terms "& gt-and" & gt-mean that the limits of the intervals are included in the described value ranges unless otherwise indicated.

In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the methods and systems according to the present invention. It will be apparent, however, to one skilled in the art that the method and system may be practiced without all of these specific details. In other instances, well-known features have not been described in detail in order to avoid complicating the description.

Fig. 1 is a block diagram schematically illustrating the principles of a slurry bed hydroconversion process 100 in accordance with the present invention. It differs from the conventional slurry bed process, for example as disclosed in document US8431016, in particular in that the catalyst precursor formulation comprises an organic additive when mixed with the oil feedstock, said catalyst precursor formulation further comprising a catalyst precursor composition comprising molybdenum, and having a specific molar ratio of organic additive to molybdenum.

In this specification, the terms "organic compound" and "organic additive" are used indifferently to denote the organic compound comprising at least one carboxylic acid function and/or at least one ester function and/or anhydride function added to the catalyst precursor formulation mixed with the heavy oil feedstock in step (a), and will be described in further detail below. The organic additive is a compound other than any possible organic compound originally present in the catalyst precursor composition.

According to the invention, a heavy oil feedstock 101 containing at least 50 wt% of a fraction having a boiling point of at least 300 ℃ and comprising metals and asphaltenes is treated in a hydroconversion process 100, said process 100 comprising the steps of:

(a) A conditioned heavy oil feedstock 103 is prepared by mixing the heavy oil feedstock 101 with a catalyst precursor formulation 104 in such a way that a colloidal or molecular catalyst is formed when the catalyst precursor formulation 104 reacts with sulfur, the catalyst precursor formulation 104 comprising:

catalyst precursor composition 105 comprising molybdenum, and

an organic compound 102 comprising at least one carboxylic acid function and/or at least one ester function and/or anhydride function, and

-the molar ratio between the organic compound 102 and molybdenum is between 0.1:1 and 20:1;

(b) Heating the conditioned heavy oil feedstock 103 from step (a) in at least one preheating device;

(c) The heated conditioned heavy oil feedstock 106 from step (b) is introduced into at least one slurry bed reactor and the slurry bed reactor is operated in the presence of hydrogen and hydroconversion conditions to produce a upgraded material 107.

In the hydroconversion process in accordance with the invention, the colloidal or molecular catalyst is formed in situ within the conditioned heavy oil feedstock in step (b) and/or step (c).

The upgraded material 107 may be further processed in optional step (d).

Each of the steps, streams and materials involved will be described in detail below.

Some of the reference numerals mentioned below are associated with fig. 6, which fig. 6 schematically illustrates an example of a slurry bed hydroconversion system 600 in accordance with the present invention, which will be described in detail after the overall process has been described in the following description.

Heavy oil feedstock

The term "heavy oil feedstock" shall refer to heavy crude oil, oil sand bitumen, bottoms of columns, and resids left over in refinery processes (e.g., visbreaker bottoms), as well as any other lower quality material containing a significant amount of high boiling hydrocarbon fractions and/or containing significant amounts of asphaltenes that can deactivate solid supported catalysts and/or cause or contribute to the formation of coke precursors and deposits.

Thus, the heavy oil feedstock 101 may comprise at least one of the following: heavy crude oil, oil sand bitumen, atmospheric bottoms, vacuum bottoms, residuum, visbreaker bottoms, coal tar, heavy oils from oil shale, liquefied coal, heavy bio-oils, and heavy oils comprising plastic waste and/or plastic pyrolysis oil.

Plastic pyrolysis oil is an oil obtained from the pyrolysis of plastics, preferably plastic waste, and may be obtained by a thermocatalytic pyrolysis treatment or may be prepared by hydropyrolysis (pyrolysis in the presence of a catalyst and hydrogen).

In particular, the treated heavy oil feedstock contains a hydrocarbon fraction, at least 50 wt%, preferably at least 80 wt%, of which has a boiling point of at least 300 ℃, preferably at least 350 ℃, or at least 375 ℃.

These are crude oils or heavy hydrocarbon fractions resulting from atmospheric and/or vacuum distillation of crude oils. They may also be atmospheric and/or vacuum residues, in particular those resulting from hydrotreatment, hydrocracking and/or hydroconversion. It may also be a vacuum distillate, a fraction from a catalytic cracking unit (e.g., fluid Catalytic Cracking (FCC)), coking, or visbreaking unit.

Preferably, they are vacuum residuum. Generally, these resids are fractions in which at least 80 wt% have a boiling point of at least 450 ℃ or higher, most typically at least 500 ℃ or 540 ℃.

Aromatic fractions, deasphalted oils (raffinate from deasphalting units) and bitumens (residue from deasphalting units) extracted from lubricant production units are also suitable as feedstock.

The feedstock may also be a residual fraction from direct Coal liquefaction (vacuum distillates and/or atmospheric and/or vacuum residuum from, for example, the registered trademark H-Coal process), coal pyrolysis products or shale oil residuum, or a residual fraction from direct liquefaction of lignocellulosic biomass, alone or in combination with Coal and/or petroleum fractions (referred to herein as "heavy bio-oils").

Examples of heavy oil feedstocks include, but are not limited to, lloydminster heavy oil, cold Lake asphalt, athabasca asphalt, urals crude oil, arabian heavy crude oil, arabian light crude oil, atmospheric bottoms, vacuum bottoms, residues (or "resid"), asphaltic residues, vacuum residuum, solvent deasphalted asphalts, and non-volatile liquid fractions left over from the distillation, thermal separation, etc. of crude oil, tar sand bitumen, liquefied coal, oil shale, or coal tar feedstock, containing higher boiling fractions and/or asphaltenes.

All these materials may be used alone or in the form of a mixture.

The heavy oil feedstock treated in the method and system according to the invention contains metals and asphaltenes (in particular C ₇ Asphaltenes) and other impurities such as sulfur and nitrogen.

The term "asphaltenes" shall mean heavy oil feedstocks that are generally insoluble in paraffinic solvents, for exampleSuch as propane, butane, pentane, hexane and heptane and contains fractions of fused ring compound sheets (sheets) held together by heteroatoms such as sulfur, nitrogen, oxygen and metals. Asphaltenes broadly include a variety of complex compounds having from 80 to 160,000 carbon atoms. Asphaltenes are in practice defined as "C" according to standard ASTM D6560 (also corresponding to standard NF T60-115) ₇ Asphaltenes ", i.e. heptane-insoluble compounds, any content of asphaltenes in this specification means C ₇ Asphaltenes. Known C ₇ Asphaltenes are compounds that inhibit the conversion of residual fractions, since they are capable of forming heavy hydrocarbon residues (commonly known as coke), and are also susceptible to producing deposits that severely limit the operability of the hydroprocessing and hydroconversion units.

The heavy oil feedstock 101 may generally have a sulfur content of greater than 0.5 wt.%, a Conradson carbon residue of at least 3 wt.%, a C of greater than 1 wt.% ₇ Asphaltene content, transition metal and/or post-transition metal and/or metalloid content of greater than 2 ppm by weight, and alkali metal and/or alkaline earth metal content of greater than 2 ppm by weight.

These types of raw materials are in fact generally rich in impurities, such as metals, in particular transition metals (e.g. Ni, V) and/or post-transition metals and/or metalloids, which may be present in amounts of more than 2 ppm by weight, or more than 20 ppm by weight, even more than 100 ppm by weight, or alkali metals (e.g. Na) and/or alkaline earth metals, which may be present in amounts of more than 2 ppm by weight, even more than 5 ppm by weight, even more than 7 ppm by weight or 10 ppm by weight.

The sulfur content is in fact generally higher than 0.5% by weight, even higher than 1% by weight, or even higher than 2% by weight.

C ₇ The asphaltene content may in fact be at least 1% by weight, even higher than 3% by weight.

Conradson carbon residue is in fact generally higher than 3% by weight, even at least 5% by weight. Conradson carbon residue is defined according to ASTM D482 and represents the amount of carbon residue produced after pyrolysis under standard temperature and pressure conditions.

These levels are expressed as weight percent of the total weight of the feed.

Step (a): preparation of conditioned heavy oil feedstock

Step (a) comprises mixing the heavy oil feedstock 101 with the catalyst precursor formulation 104 in such a way that a colloidal or molecular catalyst is formed when the catalyst precursor formulation 104 reacts with sulfur. This mixing forms what is referred to herein as a conditioned heavy oil feedstock 103.

The catalyst precursor formulation 104 comprises a catalyst precursor composition 105 comprising molybdenum and an organic compound 102 comprising at least one carboxylic acid functionality and/or at least one ester functionality and/or anhydride functionality.

The molar ratio between the organic compound 102 and molybdenum is between 0.1:1 and 20:1.

This step involves thorough mixing with the catalyst precursor formulation to form a colloidal or molecular catalyst dispersed in the heavy oil.

According to one or more embodiments, a hydrocarbon oil diluent is used to form the catalyst precursor formulation 104. Preferably, the hydrocarbon oil diluent is selected from the group consisting of vacuum gas oil, decant or recycle oil, light gas oil, vacuum residuum, deasphalted oil and resins, as described in detail below.

The inventors have demonstrated that this mixing step (a) improves the slurry boiling-entrained bed hydroconversion process, in particular by reducing fouling of the equipment, especially in the feedstock heating equipment of step b) upstream of the slurry hydroconversion reactor.

Without being bound by any theory, the presence of the organic additive during the mixing of the heavy oil feedstock with the catalyst precursor composition may provide better solubility of the colloidal or molecular catalyst precursor in the feedstock, avoid or reduce fouling, especially by deposition in equipment upstream of the slurry hydroconversion reactor (e.g. heating equipment), thereby improving the dispersibility of the colloidal or molecular catalyst formed in step b) and/or in subsequent stages, thereby yielding better accessibility of the metal active sites, facilitating hydrogenation of free radicals as precursors of coke and deposits, and significantly reducing fouling of equipment.

Organic additives

The organic additive 102 having at least one carboxylic acid functionality and/or at least one ester functionality and/or anhydride functionality preferably comprises at least 6 carbon atoms, more preferably at least 8 carbon atoms.

Typically, the organic additive 102 is neither a catalyst precursor nor a catalyst.

In particular, the organic additive 102 does not contain any metal.

Examples of organic additives include, but are not limited to, 2-ethylhexanoic acid, naphthenic acid, octanoic acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, ethyl octanoate, ethyl 2-ethylhexanoate, 2-ethylhexyl 2-ethylhexanoate, benzyl 2-ethylhexanoate, diethyl adipate, dimethyl adipate, di (2-ethylhexyl) adipate, dimethyl pimelic acid, dimethyl suberate, monomethyl suberate, hexanoic anhydride, octanoic anhydride. Advantageously, the organic additive is an organic compound selected from the specific compounds mentioned above, and mixtures thereof.

Preferably, the organic additive is an organic compound comprising at least one carboxylic acid functional group, more preferably selected from the group consisting of 2-ethylhexanoic acid, naphthenic acid, caprylic acid, adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid.

More preferably, the organic additive comprises or consists of 2-ethylhexanoic acid.

The organic additive may be an organic compound comprising at least one ester functionality and/or anhydride functionality, for example selected from ethyl octanoate, ethyl 2-ethylhexanoate, 2-ethylhexyl 2-ethylhexanoate, benzyl 2-ethylhexanoate, diethyl adipate, dimethyl adipate, di (2-ethylhexyl) adipate, dimethyl pimelate, dimethyl suberate, monomethyl suberate and/or selected from own anhydride and octanoic anhydride.

More preferably, the organic additive comprising at least one ester function and/or anhydride function comprises or consists of ethyl octanoate or 2-ethylhexyl 2-ethylhexanoate or a mixture thereof, preferably ethyl octanoate or 2-ethylhexyl 2-ethylhexanoate.

The organic additive is added such that the molar ratio of organic additive to molybdenum (which is introduced by the catalyst precursor compound, e.g., molybdenum 2-ethylhexanoate) in the catalyst precursor formulation 104 is from about 0.1:1 to about 20:1, preferably from about 0.75:1 to about 7:1, and more preferably from about 1:1 to about 5:1. The term "about" shall mean an approximation of + -5%, preferably + -1%.

Catalyst precursor formulation

The catalyst precursor formulation comprises a catalyst precursor composition selected from all molybdenum-containing metal catalyst precursors known to those skilled in the art, which are capable of being reacted under hydrogen and/or H ₂ S and/or any other sulfur source, and effecting hydroconversion of the heavy oil feedstock after injection into the heavy oil feedstock.

The molybdenum-containing catalyst precursor composition is advantageously an oil-soluble catalyst precursor composition comprising at least one transition metal.

The catalyst precursor composition preferably comprises an oil-soluble organometallic compound or complex.

The oil-soluble catalyst precursor composition preferably has a decomposition temperature of from 100 ℃ to 350 ℃, more preferably from 150 ℃ to 300 ℃, more preferably from 175 ℃ to 250 ℃ (the catalyst precursor composition is substantially chemically stable below this temperature).

The oil-soluble organometallic compound or complex is preferably selected from molybdenum 2-ethylhexanoate, molybdenum naphthenate and molybdenum hexacarbonyl.

These compounds are non-limiting examples of oil-soluble catalyst precursor compositions.

The presently preferred catalyst precursor composition is molybdenum 2-ethylhexanoate (also commonly referred to as molybdenum octoate). Typically, molybdenum 2-ethylhexanoate contains 15 wt.% molybdenum and has a decomposition temperature or range that is high enough to avoid significant thermal decomposition when mixed with a heavy oil feedstock at a temperature below 250 ℃.

In light of the present disclosure, one skilled in the art can select a certain mixing temperature profile such that mixing of the selected precursor composition does not significantly thermally decompose prior to formation of the colloidal or molecular catalyst.

Addition of organic additives

The mixing step (a) may be carried out in different ways, depending mainly on whether the organic additive is mixed with the heavy oil feedstock and the catalyst precursor composition simultaneously or introduced in a sequential manner, in particular pre-mixing the catalyst precursor composition with the organic additive to form the catalyst precursor formulation prior to mixing with the heavy oil feedstock.

The mixing step (a) advantageously includes at least the operation of a conditioning mixer 610, the conditioning mixer 610 being configured to provide thorough mixing between the feedstock and the catalyst precursor formulation 104 to form a conditioned heavy oil feedstock.

First embodiment: simultaneous mixing of oil feedstock, organic additives and catalyst precursor compositions

According to a first embodiment, step (a) comprises simultaneously mixing the organic additive 102, the catalyst precursor composition 105 (preferably pre-diluted with a hydrocarbon oil diluent) and the heavy oil feedstock 101.

According to this embodiment, during mixing with the heavy oil feedstock 101, a catalyst precursor formulation 104 is formed, which comprises a catalyst precursor composition 105 (preferably pre-diluted) and an organic additive 102.

The organic additive is added such that the molar ratio of organic additive to molybdenum (which is introduced through the catalyst precursor composition, e.g., molybdenum 2-ethylhexanoate) is from about 0.1:1 to about 20:1, preferably from about 0.75:1 to about 7:1, more preferably from about 1:1 to about 5:1, as previously described.

Such simultaneous mixing is preferably carried out at a temperature below the temperature at which most of the catalyst precursor composition begins to thermally decompose, for example at room temperature (e.g. 15 ℃) to 300 ℃, more preferably at a temperature of 50 ℃ to 200 ℃, even more preferably at a temperature of 75 ℃ to 175 ℃.

Such simultaneous mixing is performed for a time sufficient and in a manner to disperse the catalyst precursor formulation throughout the feedstock to produce a conditioned heavy oil feedstock 103, wherein the catalyst precursor composition is thoroughly mixed in the heavy oil feedstock.

Preferably, the gauge pressure is from 0MPa to 25MPa, more preferably from 0.01MPa to 5MPa.

In order to obtain an adequate mixing of the catalyst precursor composition in the heavy oil feedstock before the formation of the colloidal or molecular catalyst, the simultaneous mixing of the heavy oil feedstock 101, the organic additive 102 and the catalyst precursor composition 105 (advantageously diluted with a hydrocarbon diluent) is preferably carried out for a time of from 1 second to 30 minutes, more preferably for a time of from 1 second to 10 minutes, more preferably for a time of from 2 seconds to 3 minutes. In this specification, a mixing time (or mixing residence time) of 1 second includes instantaneous mixing.

Although it is within the scope of the present invention to mix the catalyst precursor composition 105 directly with the heavy oil feedstock 101 and the organic additive 102, in this case care must be taken to mix the components for a time sufficient to thoroughly mix the catalyst precursor composition in the feedstock prior to forming the catalyst. However, long mixing times, such as 24 hours of mixing, can make certain industrial operations cost prohibitive.

Thus, according to the first embodiment, step (a) preferably comprises diluting the catalyst precursor composition 105 prior to mixing the catalyst precursor composition 105 with the heavy oil feedstock 101 and the organic additive 102 simultaneously: pre-diluting the catalyst precursor composition 105 with a hydrocarbon diluent and then mixing the diluted catalyst precursor composition with the heavy oil feedstock and the organic additives 102 simultaneously greatly facilitates thorough and intimate mixing of the catalyst precursor composition in the feedstock, particularly in the relatively short time periods required for economically viable large-scale industrial operations.

For example, document US 2005/024781 describes such a mixing of a catalyst precursor composition (preferably an oil soluble catalyst precursor composition) with a diluent hydrocarbon stream, as will be reviewed below.

Providing a diluted catalyst precursor composition shortens the overall mixing time by: (1) Reducing or eliminating solubility differences between the more polar catalyst precursor composition and the heavy oil feedstock; (2) Reducing or eliminating rheological differences between the catalyst precursor composition and the heavy oil feedstock; and/or (3) decomposing the catalyst precursor molecules to form solutes in the hydrocarbon oil diluent, thereby being more readily dispersed within the heavy oil feedstock. In the case of heavy oil feedstocks containing water (e.g., condensed water), it is particularly advantageous to first form a diluted catalyst precursor composition. Otherwise, the affinity of water for the polar catalyst precursor composition is greater, which can lead to localized agglomeration of the catalyst precursor composition, resulting in poor dispersion, forming micron-sized or larger catalyst particles. The hydrocarbon oil diluent is preferably substantially free of water (i.e., contains less than 0.5 wt.% water, preferably less than 0.1 wt.% water, more preferably less than 750 ppm by weight water) to prevent the formation of substantial amounts of micron-sized or larger catalyst particles.

Examples of suitable hydrocarbon diluents include, but are not limited to, vacuum gas oils (which typically have a boiling range of 360 ℃ -524 ℃), decant or cycle oils (which typically have a boiling range of 360 ℃ -550 ℃), light gas oils (which typically have a boiling range of 200 ℃ -360 ℃), vacuum residuum (which typically have a boiling range of 524 ℃), deasphalted oils and resins, which are known as "VGO".

The mass ratio of catalyst precursor composition 105 to hydrocarbon oil diluent is preferably from 1:500 to 1:1, more preferably from 1:150 to 1:2, more preferably from 1:100 to 1:5 (e.g., 1:100, 1:50, 1:30, or 1:10).

While the dilution before mixing is advantageously carried out for a time of from 1 second to 30 minutes, preferably from 1 second to 10 minutes, most preferably from 2 seconds to 3 minutes. The actual time of this dilution depends at least in part on the temperature (i.e., it affects the fluid viscosity) and the intensity of the mixing performed for the dilution.

The dilution is also advantageously carried out at a temperature below the temperature at which the majority of the catalyst precursor composition begins to thermally decompose, preferably at room temperature (e.g. 15 ℃) to 300 ℃, more preferably at room temperature to 200 ℃, more preferably at 50 ℃ to 200 ℃, most preferably at 75 ℃ to 150 ℃, even more preferably at a temperature of 75 ℃ to 100 ℃.

It will be appreciated that the actual temperature at which the diluted catalyst precursor composition 105 is formed will generally depend to a large extent on the decomposition temperature of the particular precursor composition used.

The conditioning mixer 610 may include an active mixing device, any pipe injection system, or any in-line mixer, as described in detail below.

According to a first embodiment, the simultaneous mixing of step (a) may be performed in a dedicated vessel constituting the active mixing device of the conditioning mixer 610.

Such an arrangement may in particular improve the dispersibility of the colloidal or molecular catalyst formed later. The use of dedicated vessels also increases residence time.

Such simultaneous mixing may alternatively comprise injecting the organic additive 102 and catalyst precursor composition 105 (preferably pre-diluted with hydrocarbon oil diluent) into a conduit that conveys the heavy oil feedstock 101 to the slurry bed reactor (heating apparatus therebetween). Thus, in such a configuration, conditioning mixer 610 includes one or more portions of piping to perform mixing, as well as possible additional systems to aid in mixing, such as a static in-line mixer or a high shear in-line mixer, described further below. Such an arrangement may reduce equipment investment and required floor space, among other things, as compared to mixing in dedicated containers.

The conditioning mixer 610 for simultaneous mixing may also comprise a combination of a dedicated vessel of such an active mixing device and an in-line injection system that ultimately comprises a static and/or high shear in-line mixer.

Examples of mixing equipment that may be used to achieve thorough simultaneous mixing of the catalyst precursor composition 105 (preferably diluted) with the heavy oil feedstock 101 and the organic additive 102 include, but are not limited to, high shear mixing, such as that produced in a pump with a propeller or turbine wheel; a plurality of static in-line mixers; a combination of a plurality of static in-line mixers and an in-line high shear mixer; a combination of a plurality of static in-line mixers and an in-line high shear mixer; a combination of a plurality of static in-line mixers and in-line high shear mixers followed by pump around (pump around) in a buffer vessel; a combination of the above devices is then followed by one or more multistage centrifugal pumps. According to one embodiment, the mixing may be performed continuously rather than intermittently using a high energy pump having a plurality of chambers in which the catalyst precursor composition 105 (preferably diluted), the heavy oil feedstock 101, and the organic additive 102 are agitated and mixed as part of the pumping process itself. The mixing apparatus described above may also be used in the dilution stage discussed above in which the catalyst precursor composition 105 is mixed with a hydrocarbon oil diluent.

Increasing the intensity and/or shear energy of the simultaneous mixing process generally reduces the time required to achieve thorough mixing.

Second embodiment: premixing a catalyst precursor composition and an organic additive

According to a second embodiment, as schematically illustrated in fig. 2, the mixing step (a) comprises: (a1) Premixing the organic additive compound 102 with the catalyst precursor composition 105 to produce a catalyst precursor formulation 104, and (a 2) mixing the catalyst precursor formulation 104 with the heavy oil feedstock 101.

The step (a 1) of premixing the organic additive compound 102 with the catalyst precursor composition 105 to produce the catalyst precursor formulation 104 may be performed ex situ (i.e., outside the hydroconversion system).

In such a second embodiment, conditioning mixer 610 includes at least a first mixing device for step (a 1) and a second mixing device for step (a 2).

In step (a 1), the organic additive is added such that the molar ratio of organic additive 102 to molybdenum (which is introduced by the catalyst precursor composition, e.g., molybdenum 2-ethylhexanoate) in catalyst precursor formulation 104 is from about 0.1:1 to about 20:1, preferably from about 0.75:1 to about 7:1, more preferably from about 1:1 to about 5:1.

In step (a 1), the catalyst precursor composition 105 is mixed at a temperature below the temperature at which most of the catalyst precursor composition starts to thermally decompose, preferably at room temperature (e.g. 15 ℃) to 300 ℃, preferably at room temperature to 200 ℃, even more preferably at 50 ℃ to 200 ℃, more preferably at 75 ℃ to 150 ℃, even more preferably at 75 ℃ to 100 ℃.

Step (a 1)

Step (a 1) itself may be carried out in different ways as detailed below.

While it is within the scope of the present invention to mix the catalyst precursor formulation consisting of catalyst precursor composition 105 and organic additive 102 directly with heavy oil feedstock 101 in step (a 2), the method according to said second embodiment of the present invention preferably comprises using a hydrocarbon oil diluent in step (a 1) to produce catalyst precursor formulation 104, in particular to facilitate thorough, intimate mixing of the catalyst precursor composition within the feedstock in step (a 2) in the relatively short time required for economically viable large scale industrial operations.

The use of a hydrocarbon oil diluent to produce the catalyst precursor formulation 104 shortens the mixing time of step (a 2) because the differences in solubility, rheology, etc. have been given in the description above regarding the diluted catalyst precursor composition of the first embodiment.

Examples of suitable hydrocarbon diluents include, but are not limited to, vacuum gas oils (which typically have a boiling range of 360-524 ℃) known as "VGO", decant oils or cycle oils (which typically have a boiling range of 360-550 ℃) and light gas oils (which typically have a boiling range of 200-360 ℃).

The mass ratio of catalyst precursor composition 105 to hydrocarbon oil diluent in catalyst precursor formulation 104 is preferably 1:500-1: 1, more preferably 1:150 to 1:2, and most preferably 1:100 to 1:5 (e.g., 1:100, 1:50, 1:30, or 1:10).

According to one or more sub-embodiments, as schematically illustrated in fig. 3, step (a 1) of the method 300 according to the second embodiment comprises:

- (a 1) premixing the organic additive 102 with a hydrocarbon oil diluent to form a diluent-containing additive 108'; and

- (a 2) mixing the diluent-containing additive 108' with the catalyst precursor composition 105 to form the catalyst precursor formulation 104.

Step (. Alpha.1) is preferably carried out at a temperature of room temperature (e.g.15℃) to 300 ℃, preferably at a temperature of room temperature to 200 ℃, even more preferably at a temperature of 50℃to 200 ℃, more preferably at a temperature of 75℃to 150 ℃, even more preferably at a temperature of 75℃to 100 ℃.

The pressure of the pre-mixing stage (α1) is advantageously the actual pressure of the diluent stream 108. Preferably, the gauge pressure of the premixing stage (. Alpha.1) is from 0MPa to 25MPa, more preferably from 0.01MPa to 5MPa.

The residence time may be from 1 second to several days, preferably from 1 second to 30 minutes, more preferably from 1 second to 10 minutes, more preferably from 1 second to 30 seconds.

Step (α2) is preferably carried out at a temperature below the temperature at which most of the catalyst precursor composition 105 begins to thermally decompose, preferably at room temperature (e.g., 15 ℃) to 300 ℃, preferably at room temperature to 200 ℃, even more preferably at a temperature of 50 ℃ to 200 ℃, more preferably at a temperature of 75 ℃ to 150 ℃, even more preferably at a temperature of 75 ℃ to 100 ℃.

The pressure of the mixing stage (α2) is advantageously the actual pressure of stream 108'. Preferably, the gauge pressure of the mixing stage (. Alpha.2) is from 0MPa to 25MPa, more preferably from 0.01MPa to 5MPa.

It will be appreciated that the actual operating temperature in step (α2) will generally depend to a large extent on the decomposition temperature of the particular precursor composition used.

According to one or more sub-embodiments, as schematically illustrated in fig. 4, step (a 1) of the method 400 according to the second embodiment comprises:

- (β1) premixing the organic additive 102 with the catalyst precursor composition 105 to form an additive-containing catalyst precursor composition 105'; and

- (β2) mixing the additive-containing catalyst precursor composition 105' with a hydrocarbon oil diluent 108 to form the catalyst precursor formulation 104.

Step (. Beta.1) is preferably carried out at a temperature below the temperature at which most of the catalyst precursor composition 105 starts to thermally decompose, preferably at room temperature (e.g.15℃) to 300 ℃, preferably at room temperature to 200 ℃, even more preferably at a temperature of 50 ℃ to 200 ℃, more preferably at a temperature of 75 ℃ to 150 ℃, even more preferably at a temperature of 75 ℃ to 100 ℃.

Preferably, the gauge pressure of the mixing stage (. Beta.1) is from 0MPa to 25MPa, more preferably from 0.01MPa to 5MPa.

Step (. Beta.2) is preferably carried out at a temperature below the temperature at which most of the catalyst precursor composition 105 starts to thermally decompose, preferably at room temperature (e.g.15℃) to 300 ℃, preferably at room temperature to 200 ℃, even more preferably at a temperature of 50 ℃ to 200 ℃, more preferably at a temperature of 75 ℃ to 150 ℃, even more preferably at a temperature of 75 ℃ to 100 ℃.

Preferably, the gauge pressure of the mixing stage (. Beta.2) is from 0MPa to 25MPa, more preferably from 0.01MPa to 5MPa.

It will be appreciated that the actual operating temperatures in step (β1) and step (β2) generally depend to a large extent on the decomposition temperature of the particular precursor composition used.

According to one or more sub-embodiments, as schematically illustrated in fig. 5, step (a 1) of the method 500 according to the second embodiment comprises:

- (γ1) premixing the catalyst precursor composition 105 with a hydrocarbon oil diluent 108 to form a diluted catalyst precursor composition 109; and

- (γ2) mixing the diluted catalyst precursor composition 109 with an organic additive 102 to form the catalyst precursor formulation 104.

Step (γ1) is preferably carried out at a temperature below the temperature at which most of the catalyst precursor composition 105 starts to thermally decompose, preferably at room temperature (e.g. 15 ℃) to 300 ℃, preferably at room temperature to 200 ℃, even more preferably at a temperature of 50 ℃ to 200 ℃, more preferably at a temperature of 75 ℃ to 150 ℃, even more preferably at a temperature of 75 ℃ to 100 ℃.

Preferably, the gauge pressure of the mixing stage (. Gamma.1) is from 0MPa to 25MPa, more preferably from 0.01MPa to 5MPa.

Step (γ2) is preferably carried out at a temperature below the temperature at which most of the catalyst precursor composition 105 begins to thermally decompose, preferably at room temperature (e.g., 15 ℃) to 300 ℃, preferably at room temperature to 200 ℃, even more preferably at a temperature of 50 ℃ to 200 ℃, more preferably at a temperature of 75 ℃ to 150 ℃, even more preferably at a temperature of 75 ℃ to 100 ℃.

Preferably, the gauge pressure of the mixing stage (. Gamma.2) is from 0MPa to 25MPa, more preferably from 0.01MPa to 5MPa.

It will be appreciated that the actual operating temperature in step (γ1) and step (γ2) will generally depend to a large extent on the decomposition temperature of the particular precursor composition used.

The different mixing sub-steps of step (a 1) may be performed using different mixing devices, examples of which include, but are not limited to: high shear mixing, such as that produced in a vessel with a propeller or turbine wheel; a plurality of static in-line mixers; a combination of a plurality of static in-line mixers and an in-line high shear mixer; a combination of a plurality of static in-line mixers and an in-line high shear mixer; a combination of a plurality of static in-line mixers and in-line high shear mixers followed by pump circulation in a buffer vessel; a combination of the above devices followed by one or more multistage centrifugal pumps; and one or more multistage centrifugal pumps. According to one embodiment, the mixing may be performed continuously rather than intermittently using a high energy pump having a plurality of chambers in which the components to be mixed are agitated and mixed as part of the pumping process itself.

For example, each of the different mixing sub-steps of step (a 1) may be performed in a dedicated container of the active mixing device, which container is part of the first mixing device of the conditioning mixer 610.

Such an arrangement may in particular improve the dispersibility of the colloidal or molecular catalyst formed later. The use of dedicated vessels also enables high residence times.

According to another example, each of the different mixing sub-steps of step (a 1) may alternatively comprise injecting the components to be mixed into a pipe conveying the other components, herein referred to as an in-line injection system. Thus, in such a configuration, the second mixing device of conditioning mixer 610 includes one or more portions of the piping that performs the mixing, as well as possible additional systems that aid in the mixing, such as the static in-line mixer or the high shear in-line mixer described above. Such an arrangement may reduce equipment investment and required floor space, among other things, as compared to mixing in dedicated containers.

According to another example, the first mixing device of conditioning mixer 610 may comprise a combination of a dedicated container of such an active mixing device and an in-line injection system that may comprise a static and/or high shear in-line mixer.

Step (a 2)

The step (a 2) of mixing the catalyst precursor formulation 104, which already contains organic additives, with the heavy oil feedstock 101 is preferably performed at a temperature below the temperature at which most of the catalyst precursor composition starts to thermally decompose, e.g. at room temperature (e.g. 15 ℃) to 300 ℃, preferably at a temperature of 50 ℃ -200 ℃, more preferably at 75 ℃ -175 ℃, to obtain a conditioned heavy oil feedstock 103.

Step (a 2) is conducted for a time sufficient and in a manner to disperse the catalyst precursor formulation throughout the feedstock to produce a conditioned heavy oil feedstock 103, wherein the catalyst precursor composition is thoroughly mixed in the heavy oil feedstock.

In order to obtain an adequate mixing of the catalyst precursor formulation 104 in the heavy oil feedstock before the formation of the colloidal or molecular catalyst, step (a 2) is preferably carried out for a period of from 1 second to 30 minutes, more preferably for a period of from 5 seconds to 10 minutes, more preferably for a period of from 20 seconds to 3 minutes.

Step (a 2) according to the second embodiment may be performed in a dedicated container of the active mixing device constituting the second mixing device of the conditioning mixer 610.

Step (a 2) may alternatively comprise injecting the catalyst precursor formulation 104 into a conduit that delivers the heavy oil feedstock 101 to a slurry bed reactor. Thus, the second mixing device of conditioning mixer 610 includes one or more portions of the piping that performs the mixing in such a configuration, as well as possible additional systems that aid in the mixing, such as the static in-line mixer or the high shear in-line mixer described above. Such an arrangement may reduce equipment investment and required floor space, among other things, as compared to mixing in dedicated containers.

The second mixing device of conditioning mixer 610 may also comprise a combination of a dedicated vessel of such an active mixing device and an in-line injection system that may comprise a static and/or high shear in-line mixer.

Alternatively, in step (a 2), the catalyst precursor formulation 104 may be initially mixed with 20% of the heavy oil feedstock 101, the resulting mixed heavy oil feedstock may be mixed with another 40% of the heavy oil feedstock, the resulting 60% mixed heavy oil feedstock may be mixed with the remaining 40% of the heavy oil, and stepwise dilution may be performed in accordance with good engineering practices to thoroughly disperse the catalyst precursor formulation 104 in the heavy oil feedstock. In the stepwise dilution method, the mixing time in a suitable mixing device or method as described herein should still be used.

The process according to the invention is preferably carried out according to a second embodiment, wherein step (a) comprises: (a1) Premixing the organic additive compound 102 with the catalyst precursor composition 105 to produce a catalyst precursor formulation 104, and (a 2) mixing the catalyst precursor formulation 104 with the heavy oil feedstock 101.

In step (a), the mixing of the heavy oil feedstock 101 with the catalyst precursor formulation 104 may be performed on part or all of the heavy oil feedstock 101.

According to one or more preferred embodiments, the mixing step (a) is performed between the catalyst precursor formulation 104 and the entire stream of heavy oil feedstock 101 that is sent to the hydroconversion system. In one or more alternative embodiments, the mixing step (a) is performed between the catalyst precursor formulation 104 and a portion of the stream sent to the hydroconverted heavy oil feedstock 101. Thus, the conditioned heavy oil feedstock 103 may be prepared by mixing at least a portion of the stream of the heavy oil feedstock 101 (e.g., at least 50 wt% of the stream of the heavy oil feedstock 101) with the catalyst precursor formulation 104. Once the catalyst precursor formulation 104 is added, a supplemental portion of the stream of heavy oil feedstock 101 may be re-added, which is mixed with the conditioned heavy oil feedstock 103 prior to preheating it in step (b).

Step (b): heating conditioned heavy oil feedstock

The conditioned oil feedstock 103 formed in step (a) is then heated in at least one preheating device 630 and then introduced into a slurry bed reactor for hydroconversion.

The conditioned oil feedstock 103 (optionally pressurized by a pump) is sent to at least one preheating device 630.

The preheating means includes any heating means known to those skilled in the art capable of heating the heavy oil feedstock. The preheating device may comprise a furnace with at least a preheating chamber, and/or a conduit through which the oil feedstock flows, a conditioned oil feedstock and H ₂ Any type of suitable heat exchanger, such as a tubular or spiral heat exchanger through which the oil feedstock flows, etc.

This preheating of the conditioned heavy oil feedstock may allow the slurry hydroconversion reactor to reach the target temperature in a later step d).

More preferably, the conditioned oil feedstock 103 is heated in the preheating device 630 to a temperature of 280 ℃ to 450 ℃, more preferably 300 ℃ to 400 ℃, most preferably 320 ℃ to 365 ℃, especially in order to subsequently reach the target temperature in the hydroconversion reactor in step (c).

The surface temperature of the preheating device, for example the surface temperature of the furnace or the chamber of the heat exchanger or the steel shell of the tube, can reach 400-650 ℃. In step (a), the catalyst precursor formulation 104 comprising the catalyst precursor composition 105 and the organic additive 102 is mixed with the heavy oil feedstock 101 to avoid or reduce fouling that may occur in the preheating equipment at these high temperatures.

According to one or more embodiments, the conditioned feedstock is heated to a temperature 100 ℃ below, preferably 50 ℃ below, the hydroconversion temperature in the slurry hydroconversion reactor. For example, for hydroconversion temperatures in the range 410 ℃ to 440 ℃, the conditioned oil feedstock may be heated in step (b) to a temperature in the range 310 ℃ to 340 ℃.

The absolute pressure is from atmospheric pressure (e.g., 0.101325 MPa) to 38MPa, preferably from 5MPa to 25MPa, and preferably from 6MPa to 20MPa.

The heating performed in this step (b) advantageously causes the conditioned oil feedstock to release sulfur, which may be bound to the metal of the catalyst precursor composition.

According to one or more embodiments, in step (b) of heating in the preheating device 630, a colloidal or molecular catalyst is formed in situ, or at least begins to form, in the conditioned heavy oil feedstock.

In order to form a colloidal or molecular catalyst, sulfur is necessary (e.g., as H ₂ S) is combined with a metal from the catalyst precursor composition.

In situ formation of colloidal or molecular catalysts in conditioned heavy oil feedstock

The general in situ formation of the colloidal or molecular catalyst within the conditioned heavy oil feedstock, and the conditions required for such formation in step (b) and/or step (c), are described in detail below.

Where the heavy oil feedstock contains sufficient or excess sulfur, the final activated catalyst may be formed in situ by heating the conditioned heavy oil feedstock 103 to a temperature sufficient to release sulfur therefrom.

Thus, the sulfur source may be H dissolved in the heavy oil feedstock ₂ S, or H contained in hydrogen recycled to the slurry bed hydroconversion reactor for hydroconversion ₂ S, or from a sulfur-containing hydrocarbon feedstock of any type, e.g. mercaptans, sulfides, sulfur-containing petroleum, sulfur-containing gas oil, sulfur-containing vacuum distillation, present in the feedstock or possibly introduced beforehand into the heavy oil feedstock (dimethyl disulfide, thioacetamide)Effluent, injection of sulfur-containing residuum) organic sulfur molecules H ₂ S, such injection is rarely used only for very typical heavy oil feedstocks.

Thus, the sulfur source may be a sulfur-containing compound within the feedstock or a sulfur-containing compound added to the feedstock.

According to one or more embodiments, the formation of the dispersed colloidal or molecular catalyst is carried out at an absolute pressure of from atmospheric pressure to 38MPa, preferably from 5MPa to 25MPa, more preferably from 6MPa to 20 MPa.

Since thorough mixing is performed in step (a), a molecular dispersion catalyst may be formed when reacting with sulfur to form metal sulfides. In some cases, slight agglomeration may occur, resulting in colloidal-sized catalyst particles. However, it is believed that careful mixing of the precursor formulation throughout the heavy oil feedstock in step (a) will result in individual catalyst molecules rather than colloidal particles. Simply added together without thorough mixing, typically forming large agglomerates of metal sulfide on the order of microns or larger.

For the formation of the metal sulphide catalyst, the conditioned feedstock 103 is preferably heated to a temperature of from room temperature (e.g. 15 ℃) to 500 ℃, more preferably from 200 ℃ to 500 ℃, even more preferably from 250 ℃ to 450 ℃, even more preferably from 300 ℃ to 435 ℃.

The temperature used in step (b) and/or step (c) may form a metal sulphide catalyst.

Thus, a colloidal or molecular catalyst may be formed at least in part during this heating step (b), and then the heated conditioned feedstock 106 is introduced into the slurry bed hydroconversion reactor in step (c).

The colloidal or molecular catalyst may also be formed in situ in the slurry bed hydroconversion reactor of step (c), in particular wholly or in part in the case where it has already started to form in step (b).

The molybdenum concentration in the conditioned oil feedstock is preferably in the range of from 10 ppm by weight to 10000 ppm by weight, more preferably in the range of from 50 ppm by weight to 6000 ppm by weight, more preferably in the range of from 100 ppm by weight to 1000 ppm by weight, even more preferably in the range of from 100 ppm by weight to 800 ppm by weight, even more preferably in the range of from 150 ppm by weight to 400 ppm by weight, of the heavy oil feedstock 101.

Mo may become more concentrated when volatile fractions are removed from the non-volatile residuum fraction.

Since colloidal or molecular catalysts tend to be very hydrophilic, individual particles or molecules tend to migrate to more hydrophilic parts or molecules of the heavy oil feedstock, especially asphaltenes. Although the high polarity of the catalyst compound results in or allows binding of the colloidal or molecular catalyst to the asphaltene molecules, it is precisely due to the general incompatibility between the highly polar catalyst compound and the hydrophobic heavy oil feedstock that the oil-soluble catalyst precursor formulation needs to be intimately or thoroughly mixed with the heavy oil feedstock prior to formation of the colloidal or molecular catalyst.

Preferably, the colloidal or molecular catalyst comprises molybdenum disulfide.

In theory, nanoscale molybdenum disulfide crystals have 7 molybdenum atoms sandwiched between 14 sulfur atoms, with the total number of molybdenum atoms exposed at the edges (and thus available for catalytic activity) being greater than that of the microscale molybdenum disulfide crystals. In fact, the small catalyst particles formed in the present invention, i.e., colloidal or molecular catalysts, have enhanced dispersibility, and thus more catalyst particles and more uniform distribution of catalyst sites throughout the oil feedstock. Furthermore, it is believed that nano-sized or smaller molybdenum disulfide particles are intimately associated with the asphaltene molecules.

Step (c): hydroconversion of heated conditioned feedstock

The heated conditioned feedstock 106 (optionally pressurized by a pump, particularly where not already pressurized prior to step (b)) is then introduced into at least one slurry bed reactor 640 along with hydrogen 601 and operated under hydroconversion conditions to produce a upgraded material 107.

As mentioned previously, if not formed completely or not at all in step (b), the colloidal or molecular catalyst may be formed in situ in the slurry bed hydroconversion reactor in step (c).

When the colloidal or molecular catalyst is formed in situ in the conditioned heavy oil feedstock in step (b), the heated conditioned feedstock 106 already contains some or all of the colloidal or molecular catalyst upon entering the at least one slurry bed reactor 640.

The slurry boiling-entrained bed reactor 640 comprises a liquid phase containing the heated conditioned feedstock 106 containing colloidal or molecular catalyst dispersed therein and a gas phase containing hydrogen.

Such slurry bed reactors are well known to those skilled in the art.

The slurry bed reactor preferably comprises an upward flow of liquid and gas.

The slurry bed reactor for hydroconversion of heavy hydrocarbon oils, like most slurry bed reactors, can be an empty plug flow type vessel because the conditioned heavy oil feedstock 106 containing colloidal or molecular catalyst dispersed therein appears homogeneous.

During operation with liquid and gas upward flow, the slurry bed reactor preferably includes an inlet at or near the bottom of the slurry bed reactor through which heated conditioned feedstock 106 is introduced with hydrogen 201, and an outlet at or near the top of the reactor through which upgraded material 107 is withdrawn. Colloidal or molecular hydroconversion catalyst is dispersed throughout the feedstock within the slurry bed reactor and entrained out of the reactor with the effluent comprising upgraded material 107.

The slurry bed reactor may include an agitator at its bottom to help disperse the hydrogen more uniformly within the feedstock.

The slurry phase reactor may comprise a previous ebullated bed reactor, which is converted to a slurry phase reactor by removing the porous supported catalyst from the previous ebullated bed reactor. In such cases, the slurry bed reactor may include a stirrer at its bottom, alternatively or in addition to such a stirrer, the slurry bed reactor may include a recirculation channel, a recirculation pump, a distributor grid plate as in a conventional ebullated bed reactor, which allows for continuous recirculation with at least a portion of the liquid fraction withdrawn from the top of the reactor and re-injected at the bottom of the reactor, and promotes a more even dispersion of reactants, catalyst and heat, and also includes a cup-shaped riser as exemplified in document US 6960325B.

If an internally recycled feed is used, such an internally recycled feed may be mixed with fresh heated conditioned feed 106 and make-up hydrogen 201.

The presence of a colloidal or molecular catalyst within the slurry bed reactor provides catalytic hydrogenation activity. As previously mentioned, the capping of the free radicals minimizes the formation of deposits and coke precursors.

In hydroconversion step (c), the heated conditioned feedstock 106 is typically converted under conventional heavy oil feedstock hydroconversion conditions.

According to one or more embodiments, the hydroconversion step (c) is carried out at an absolute pressure of from 2 to 38MPa, preferably from 5 to 25MPa, preferably from 6 to 20MPa, at a temperature of from 300 ℃ to 550 ℃, preferably from 350 ℃ to 500 ℃, preferably from 370 ℃ to 450 ℃, more preferably from 400 ℃ to 440 ℃, even more preferably from 410 ℃ to 435 ℃.

According to one or more embodiments, the Liquid Hourly Space Velocity (LHSV) of the feedstock relative to the volume of each slurry bed reactor is 0.05h ^-1 For 10h ^-1 Preferably 0.10h ^-1 For 2h ^-1 Preferably 0.10h ^-1 For 1h ^-1 . According to another embodiment, the LHSV is 0.05h ^-1 To 0.09h ^-1 . LHSV is defined as the liquid feed volume flow per reactor volume at room temperature and atmospheric pressure (typically 15 ℃ and 0.101325 MPa).

According to one or more embodiments, the amount of hydrogen mixed with the heavy oil feedstock 106 is preferably 50-5000 standard cubic meters (Nm) ³ Cubic meter (m) ³ ) Liquid heavy oil feedstock, e.g. 100-2000Nm ³ /m ³ Preferably 500-1500Nm ³ /m ³ 。

According to one or more embodiments, the hydroconversion step (c) is carried out in one or more slurry bed hydroconversion reactors, which may be connected in series and/or in parallel.

Step (d): further processing of the upgraded material from hydroconversion step (c)

The upgraded material 107 may be further processed.

Examples of such further processing include, but are not limited to, at least one of: separating a hydrocarbon fraction of the upgraded material, further hydroconverting in one or more supplemental slurry bed reactors or mixed boiling-entrainment reactors or ebullated bed reactors (which may be in series and/or parallel) to produce a further upgraded material, fractionating the hydrocarbon fraction of the further upgraded material, deasphalting at least a portion of the upgraded material 107 or a heavy liquid fraction produced from the fractionation of the upgraded material or the further upgraded material, purifying the upgraded material or the further upgraded material in a guard bed to remove at least a portion of colloidal or molecular catalyst and metal impurities.

The various hydrocarbon fractions that may be produced from upgraded material 107 may be sent to different processes at the refinery, and the details of these post-treatment operations are not described herein, as they are generally known to the skilled artisan and may result in meaningless complications to the description. For example, gas fractions, naphtha, middle distillates, VGO, DAO may be sent to hydrotreating, steam cracking, fluid Catalytic Cracking (FCC), hydrocracking, lube oil extraction, etc., and resids (atmospheric or vacuum resids) may also be post-treated or used for other applications such as gasification, bitumen production, etc. The heavy fraction comprising residuum may also be recycled to the hydroconversion process, such as a slurry bed reactor.

According to one or more embodiments, as shown in fig. 6, the method further comprises:

a second hydroconversion step in a second slurry bed reactor 660 in the presence of hydrogen 604 of at least a portion or all of the upgraded material resulting from hydroconversion step (c), or of an optional liquid heavy fraction 603 resulting from an optional separation step (separating a portion or all of the upgraded material resulting from hydroconversion step (c)), boiling predominantly at a temperature greater than or equal to 350 ℃, said second slurry bed reactor 660 being operated at hydroconversion conditions to produce a hydroconverted liquid effluent 605 having a reduced heavy residuum fraction, a reduced conradson carbon residue, and possibly a reduced amount of sulfur and/or nitrogen;

a step of fractionating a part or all of the hydroconverted liquid effluent 605 in a fractionation section 670 to produce at least one heavy fraction 607, the heavy fraction 607 boiling mainly at a temperature greater than or equal to 350 ℃, the heavy fraction containing a residuum fraction boiling at a temperature greater than or equal to 540 ℃;

a step of deasphalting a portion or all of said heavy fraction 607 with at least one hydrocarbon solvent in a deasphalter 680 to produce a deasphalted oil DAO 608 and a residual asphalt 609.

The second hydroconversion step is carried out in a similar manner to the description of hydroconversion step (c) and, therefore, will not be described in detail herein. The operating conditions and the equipment used are particularly suitable, except for the description given below.

As for the hydroconversion step (c), the second hydroconversion step is carried out in a second slurry bed reactor 660 similar to the slurry bed reactor 640.

In this additional hydroconversion step, the operating conditions may be similar to or different from those in hydroconversion step (c), the temperature being maintained at 300-550 ℃, preferably 350-500 ℃, more preferably 370-450 ℃, even more preferably 400-440 ℃, even more preferably 410-435 ℃, and the amount of hydrogen introduced into the reactor being maintained at 50-5000Nm ³ /m ³ Preferably 100-2000Nm ³ /m ³ Even more preferably 500-1500Nm ³ /m ³ . Other pressure and LHSV parameters are within the same ranges as those described in relation to hydroconversion step (c).

An optional separation step is performed in separation section 650 that separates a portion or all of upgraded material 107 to produce at least two fractions, including a heavy liquid fraction 603 that boils predominantly at a temperature greater than or equal to 350 ℃.

The other one or more fractions 602 are one or more light and middle fractions. The light fraction thus separated mainly comprises gas (H ₂ 、H ₂ S, NH3 and C ₁ -C ₄ ) Stone and stoneBrain oil (fraction boiling at a temperature below 150 ℃), kerosene (fraction boiling at 150 ℃ to 250 ℃) and at least a portion of diesel (fraction boiling at 250 ℃ to 375 ℃). The light fraction may then be at least partially sent to a fractionation unit (not shown in fig. 6) where light gases are extracted from the light fraction, for example by passing through a flash tank. The gaseous hydrogen thus recovered, which has been sent to the purification and compression equipment, can advantageously be recycled to the hydroconversion step (c). The recovered gaseous hydrogen may also be used in other facilities in the refinery.

Separation section 650 includes any separation device known to those skilled in the art. It may comprise one or more flash tanks arranged in series, and/or one or more steam and/or hydrogen strippers, and/or an atmospheric distillation column, and/or a vacuum distillation column, preferably consisting of a single flash tank, commonly referred to as a "thermal separator".

The fractionation step to separate a portion or all of the hydroconverted liquid effluent from the second hydroconversion step to produce at least two fractions comprising at least one heavy liquid fraction 607 boiling predominantly at a temperature above 350 ℃, preferably above 500 ℃, preferably above 540 ℃ is carried out in a fractionation stage 670 comprising any separation equipment known to a person skilled in the art. The other one or more fractions 606 are one or more light and middle fractions.

The heavy liquid fraction 607 comprises a fraction boiling at a temperature above 540 ℃, known as vacuum residuum (which is unconverted fraction). It may comprise a portion of the diesel fraction boiling at 250 ℃ to 375 ℃ and a fraction boiling at 375 ℃ to 540 ℃ (referred to as reduced pressure distillate).

The fractionation section 670 may comprise one or more flash tanks arranged in series, and/or one or more steam and/or hydrogen strippers, and/or an atmospheric distillation column, and/or a vacuum distillation column, preferably consisting of a set of multiple flash tanks in series, and an atmospheric distillation column and a vacuum distillation column.

If it is desired to recycle a portion of the heavy residuum fraction (e.g., a portion of the heavy liquid fraction 107 and/or a portion of the residual bitumen 609 or a portion of the DAO 608) back into the hydroconversion system (e.g., slurry bed reactor 640 or upstream), it may be advantageous to leave colloidal or molecular catalyst in the residuum and/or residual bitumen fraction. The recycle stream may be vented, typically to prevent excessive accumulation of some compounds.

The present invention also relates to a slurry bed system 600 configured to hydroconvert a heavy oil feedstock 101 as described above. The reference numbers mentioned below are related to fig. 6, which schematically illustrates one example of a slurry bed hydroconversion system in accordance with the present invention. The system 600 includes:

A conditioning mixer 610 configured to prepare a conditioned feedstock 103 by mixing the heavy oil feedstock 101 with a catalyst precursor formulation 104, the catalyst precursor formulation 104 comprising a molybdenum-containing catalyst precursor composition 105 and an organic additive, the molar ratio between the organic compound 102 and molybdenum being from 0.1:1 to 20:1;

at least one preheating device 630 configured to heat the conditioned feedstock 103;

at least one slurry bed reactor 640 configured to include:

-a liquid hydrocarbon phase comprising a heated conditioned feedstock 106 containing a colloidal or molecular catalyst dispersed therein;

-a gas phase comprising hydrogen.

The at least one slurry bed reactor 640 is configured to operate in the presence of hydrogen and under hydroconversion conditions to thermally crack hydrocarbons in the heated conditioned feedstock to provide the upgraded material 107.

The at least one preheating device 630 and/or the at least one slurry bed reactor 640 are also configured to form a colloidal or molecular catalyst in the conditioned heavy oil feedstock.

Details about each device/apparatus/section used in the slurry bed system have been given above in connection with the method and are not repeated.

Examples

The following examples illustrate, in a manner that does not limit the scope of the invention, some of the properties of the methods and systems according to the invention, particularly the reduction of equipment fouling, as compared to prior art methods and systems.

The examples are based on tests performed using an analytical device from Alcor company called "Alcor Hot Liquid Process Simulator" or HLPS, which simulates the fouling effect of Atmospheric Residuum (AR) in a heat exchanger. AR pumping was run through a heating tube (laminar flow shell and tube heat exchanger) under controlled conditions and scale deposits formed on the heating tube. The temperature of the AR exiting the heat exchanger is related to the effect of the deposit on the efficiency of the heat exchanger. The decrease in the AR liquid outlet temperature from its initial maximum is referred to as Δt, and is related to the amount of sediment. The greater the delta T drop, the higher the amount of fouling and deposits.

HLPS testing can be used to evaluate scaling trends for different ARs by comparing the slope of the decrease in AR liquid outlet temperature obtained under the same test conditions. The effect of the organic additive can also be determined by comparing test results from a pure sample (not containing the organic additive) with a sample incorporating the organic additive.

Two samples were tested: sample 1 is a mixture of a heavy oil feedstock and a molecular or colloidal catalyst according to the prior art, and sample 2 is a mixture according to the invention comprising the same heavy oil feedstock and the same molecular or colloidal catalyst, and further comprising an organic additive.

The heavy oil feedstock ("feed") used was Atmospheric Residuum (AR), the main compositions and properties of which are given in table 1 below.

TABLE 1

Sample 1: sample 1 is a mixture of feed and a Catalyst Precursor Composition (CPC) of molybdenum 2-ethylhexanoate diluted in Vacuum Gas Oil (VGO).

The composition of VGO is given in Table 1 above.

Molybdenum 2-ethylhexanoate was mixed with VGO at a temperature of 70 ℃ for a period of 30 minutes to obtain CPC solution. The molybdenum content in the CPC solution containing VGO was 3500 ppm by weight.

The CPC solution was then mixed with the feed (AR) at a temperature of 70 ℃ for a period of 30 minutes.

The Mo content in sample 1 was 283 ppm by weight (see Table 2 below).

Sample 2: sample 2 is a mixture of feed (AR) and the same CPC solution (molybdenum 2-ethylhexanoate diluted with VGO) as in sample 1, and an organic additive that is 2-ethylhexanoic acid (2 EHA). The CAS number for 2EHA is 149-57-5.

The CPC solution obtained as described for sample 1 was first mixed with 2EHA at a temperature of 70 ℃ for a period of 30 minutes.

The CPC solution containing organic additive 2EHA was then mixed with the feed (AR) at a temperature of 70 ℃ for a period of 30 minutes.

The Mo content in sample 2 was 283 ppm by weight (see Table 2 below).

The concentration of organic additive 2EHA was 5761 ppm by weight (see table 2 below).

Molar ratio 2 EHA/mo=13.6.

TABLE 2

The Mo content in the sample was determined according to ASTM D7260. The content of the acid and ester organic additives is determined by weighing.

HLPS test conditions are given in table 3 below.

TABLE 3

Test results of different samples (sample 1 is S ₁ Sample 2 is S ₂ ) As shown in the graph of fig. 7. The X-axis represents the time in hours, and the Y-axis represents the temperature [ T ] of the oil mixture (sample) exiting the pipe at time T _{Effluent oil} ] _t Maximum temperature of oil mixture (sample) with outflow conduit [ T ] _{Effluent oil} ] _{Maximum value} The temperature difference DeltaT between: Δt= [ T ] _{Effluent oil} ] _t -[T _{Effluent oil} ] _{Maximum value} 。

The results show that sample 1 has a strong tendency to scale because its Δt drops very rapidly. Sample 2, which contains an organic additive (e.g., 2 EHA) according to the present invention, has a lower Δt value than sample 1, indicating a significant reduction in fouling behaviour by the organic additive.

Claims

1. A process for hydroconversion of a heavy oil feedstock (101), said heavy oil feedstock (101) comprising at least 50 wt% of a fraction having a boiling point of at least 300 ℃ and comprising metals and asphaltenes, said process comprising the steps of:

(a) Preparing a conditioned heavy oil feedstock (103) by mixing the heavy oil feedstock (101) with a catalyst precursor formulation (104) in such a way that a colloidal or molecular catalyst is formed when the catalyst precursor formulation (104) is reacted with sulfur, the catalyst precursor formulation (104) comprising:

-a catalyst precursor composition (105) comprising molybdenum, and

-an organic compound (102) comprising at least one carboxylic acid function and/or at least one ester function and/or anhydride function, and

-the molar ratio between the organic compound (102) and molybdenum in the catalyst precursor formulation (104) is between 0.1:1 and 20:1;

(b) Heating the conditioned heavy oil feedstock (103) from step (a) in at least one preheating device;

(c) Introducing the heated conditioned heavy oil feedstock (106) from step (b) into at least one slurry bed reactor and operating the slurry bed reactor in the presence of hydrogen and hydroconversion conditions to produce a upgraded material (107); and wherein

2. The method of claim 1, wherein step (a) comprises mixing the organic compound (102) with the catalyst precursor composition (105) and the heavy oil feedstock (101) simultaneously, preferably the catalyst precursor composition (105) is pre-diluted with a hydrocarbon oil diluent, preferably at a temperature below which most of the catalyst precursor composition starts to thermally decompose, e.g. at a temperature of room temperature to 300 ℃ for a period of 1 second to 30 minutes.

3. The method of claim 1, wherein step (a) comprises: (a1) Premixing the organic compound (102) with the catalyst precursor composition (105) to produce the catalyst precursor formulation (104) and (a 2) mixing the catalyst precursor formulation (104) with the heavy oil feedstock (101).

4. A process according to claim 3, wherein in step (a 1) the catalyst precursor composition (105) is mixed at a temperature below the temperature at which a substantial part of the catalyst precursor composition starts to thermally decompose, preferably at a temperature of from room temperature to 300 ℃.

5. The method of any of the preceding claims, wherein a hydrocarbon oil diluent, preferably selected from the group consisting of vacuum gas oil, decant oil or recycle oil, light gas oil, vacuum resid, deasphalted oil, and resin, is used to form the catalyst precursor formulation (104).

6. The process of any of the preceding claims, wherein the organic compound (102) is selected from the group consisting of ethylhexanoic acid, naphthenic acid, octanoic acid, adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid, ethyl octanoate, ethyl 2-ethylhexanoate, 2-ethylhexyl 2-ethylhexanoate, benzyl 2-ethylhexanoate, diethyl adipate, dimethyl adipate, di (2-ethylhexyl) adipate, dimethyl pimelic acid, dimethyl suberate, monomethyl suberate, hexanoic anhydride, octanoic anhydride, and mixtures thereof.

7. The process of claim 6, wherein the organic compound (102) comprises 2-ethylhexanoic acid, preferably 2-ethylhexanoic acid.

8. The process of claim 6, wherein the organic compound (102) comprises ethyl octanoate or 2-ethylhexyl 2-ethylhexanoate, preferably ethyl octanoate or 2-ethylhexyl 2-ethylhexanoate.

9. The process of any one of the preceding claims, wherein the catalyst precursor composition comprises an oil-soluble organometallic compound or complex selected from molybdenum 2-ethylhexanoate, molybdenum naphthenate, molybdenum hexacarbonyl, preferably molybdenum 2-ethylhexanoate.

10. The method of any of the preceding claims, wherein the molar ratio between the organic compound (102) and molybdenum of the catalyst precursor formulation (104) is 0.75:1-7:1, preferably 1:1-5:1.

11. The method of any one of the preceding claims, wherein the colloidal or molecular catalyst comprises molybdenum disulfide.

12. A process according to any one of the preceding claims, wherein step (b) comprises heating at a temperature of 280 ℃ to 450 ℃, more preferably 300 ℃ to 400 ℃, most preferably 320 ℃ to 365 ℃.

13. The method of any of the preceding claims, wherein the heavy oil feedstock (101) comprises at least one of the following: heavy crude oil, oil sand bitumen, atmospheric bottoms, vacuum bottoms, residuum, visbreaker bottoms, coal tar, heavy oils from oil shale, liquefied coal, heavy bio-oils, and heavy oils comprising plastic waste and/or plastic pyrolysis oil.

14. The process of any of the preceding claims, wherein the heavy oil feedstock (101) has a sulfur content of greater than 0.5 wt%, a conradson carbon residue of at least 0.5 wt%, a C of greater than 1 wt% ₇ Asphaltene content, transition metal and/or post-transition metal and/or metalloid content of greater than 2 ppm by weight, and alkali metal and/or alkaline earth metal content of greater than 2 ppm by weight.

15. The process of any of the preceding claims, wherein the reaction is carried out at a temperature of 300 ℃ to 550 ℃ for 0.05h at an absolute pressure of 2MPa to 38MPa ^-1 For 10h ^-1 The hydroconversion step (c) is carried out at a liquid hourly space velocity LHSV relative to the volume of each slurry bed reactor and at an amount of hydrogen mixed with the feed entering the slurry bed reactor of 50-5000 standard cubic meters (Nm 3) per cubic meter (m 3) of feed.

16. The method of any of the preceding claims, wherein the concentration of molybdenum in the conditioned oil feedstock is from 10 ppm to 10000 ppm by weight of heavy oil feedstock.