EA041453B1 - IMPROVED BOILING-BED REACTOR WITHOUT GROWTH OF RECYCLING ASPHALTENES IN VACUUM RESIDUES - Google Patents

Description

State of the art

1. Technical field

The present invention relates to crude oil hydroprocessing methods and systems, including fluidized bed hydroprocessing methods and systems, which use a two-way catalyst system with recirculation of vacuum residues and no buildup of recycled asphaltenes.

2. Prior Art

Converting heavy oil to useful commercial products involves extensive processing such as lowering the boiling point of the heavy oil, increasing the hydrogen to carbon ratio, and removing impurities such as metals, sulfur, nitrogen, and coke precursors. Examples of hydrocracking processes that use conventional heterogeneous catalysts to upgrade atmospheric bottoms include fixed bed hydroprocessing, fluidized bed hydroprocessing, and moving bed hydroprocessing.

Non-catalytic advanced processes for beneficiation of vacuum tower bottoms include thermal cracking such as delayed coking, flexicoking, light cracking, and solvent extraction.

There is an ever-increasing demand for more efficient use of feedstock from heavy oil and for the extraction of fuel calorific value from it. Low quality feedstocks are characterized as containing relatively high amounts of hydrocarbons that have a nominal boiling point of 524°C (975°F) or higher. It also contains relatively high concentrations of sulfur, nitrogen and/or metals. The high boiling fractions produced from these inferior feedstocks typically have a high molecular weight (often referred to as higher density and viscosity) and/or a hydrogen/carbon ratio which is associated with the presence of high concentrations of undesirable components including asphaltenes and carbon residue. Asphaltenes and carbon residue are difficult to process and typically cause fouling of conventional catalysts and hydroprocessing equipment due to their contribution to coke and deposits.

Low quality heavy oil feedstocks contain higher concentrations of asphaltenes, carbon residue, sulfur, nitrogen and metals. Examples include heavy crude oil, oil sand bitumen, and bottoms from conventional refining. Bottoms (or residue) may refer to atmospheric column residues or vacuum column residues. The boiling point of the bottoms of the atmospheric column may be at least 343°C (650°F), although it should be understood that the boundary temperature of the separation of the distillation fraction may vary depending on the refinery and can be up to 380°C (716°F). The boiling point of the vacuum column bottoms (also known as bottom tars or vacuum bottoms) can be at least 524°C (975°F), although it should be understood that the cutoff cutoff temperature may vary depending on refinery units and can be up to up to 538°C (1000°F) or even 565°C (1050°F).

In comparison, Alberta light crude oil contains approximately 9 volume% vacuum residue, while heavy Lloydminster oil contains approximately 41 volume% vacuum residue, cold lake bituminous oil contains approximately 50 volume% vacuum residue, and Athabasca bitumen contains approximately 51 volume .% vacuum residue. When further compared, relatively light oil such as Dansk Blend from the North Sea region contains only about 15% vacuum residue, while low-quality European oil such as Ural contains more than 30% vacuum residue, and oil such as Arabian medium contains even higher, about 40% vacuum residue.

In this fluidized bed system, the rate of production of conversion products is often limited by fouling. When attempts are made to increase the production of conversion products beyond a certain practical limit, the fouling rate of certain heat exchangers or other process equipment becomes too high, requiring more frequent shutdowns for maintenance and cleaning. One of the ways to increase the production of conversion products is the recycling of vacuum residues formed during the vacuum distillation of enriched hydrocarbons obtained in a fluidized bed reactor. However, this usually causes a buildup of recycled asphaltenes in the vacuum bottoms, limiting the ability to maintain the desired conversion rate without deposit buildup and equipment fouling. It also enables low quality vacuum residue products to be obtained which can be used as fuel oil.

Typically, the refinery will relate the observed equipment fouling rate to the deposit measurements and will reach an operational deposit limit above which the refinery will shut down the fluidized bed hydrocracking unit. In addition, the formation of deposits and clogging of equipment impose restrictions on the subsequent processing of high-boiling fractions. They also limit or prevent recirculation of vacuum residues to the hydroprocessing reactor. Such problems are exacerbated when low quality heavy oil feedstocks are used. Even when refiners

- 1 041453 The plant finds a way to process the vacuum residues, the result can be a final bottoms product that is of poor quality and does not meet the minimum standards for use as a fuel oil. There is still a need to find ways to process vacuum residues that do not cause the buildup of recycled asphaltenes, which increases the likelihood of clogging and equipment shutdowns and leads to the production of poor quality bottoms.

Statement of the Invention

Disclosed herein are methods for improving a fluidized bed hydroprocessing system to allow vacuum residues to be recycled without buildup of recycled asphaltenes. In addition, improved fluidized bed hydroprocessing systems are disclosed that use recycled vacuum residues without buildup of recycled asphaltenes. The disclosed methods and systems include the use of a two-component catalyst system consisting of a supported solid catalyst and well-dispersed (eg, homogeneous) catalyst particles. The two-way catalytic system allows the operation of a fluidized bed reactor with recirculation of vacuum residues without buildup of recycled asphaltenes in a fluidized bed hydroprocessing system.

In some embodiments, a method for improving a fluidized bed hydroprocessing system to allow recycling of vacuum residues without buildup of recycled asphaltenes includes the following steps: (1) operating a fluidized bed reactor using a heterogeneous heavy oil hydroprocessing catalyst at baseline, optionally with recirculation of vacuum residues and buildup of recirculating asphaltenes; (2) adding or forming in situ particulate metal sulfide catalyst particles in a fluidized bed reactor to obtain an improved fluidized bed reactor with a two-way catalyst system consisting of a heterogeneous catalyst and particulate metal sulfide catalyst particles; (3) operation of an improved fluidized bed reactor using a two-way catalyst system for hydroprocessing heavy oil to produce hydrocarbon products; (4) subjecting the hydrocarbon products to vacuum distillation and separating distillates from vacuum residues containing particles of residual metal sulfide catalyst; and (5) recycling at least a portion of the vacuum residues containing residual metal sulfide catalyst particles to the improved fluidized bed reactor without buildup of recycled asphaltenes in the fluidized bed hydroprocessing system.

In some embodiments, the operation of an improved fluidized bed reactor using a two-way catalyst system with recirculation of vacuum residues includes the following steps:

(i) operating the improved fluidized bed reactor at a higher conversion than baseline without the buildup of recycled asphaltenes in the fluidized bed hydroprocessing system;

(ii) operating the improved fluidized bed reactor at a similar conversion compared to baseline conditions with reduced asphaltenes in vacuum residues or (iii) operating the improved fluidized bed reactor at a higher conversion compared to baseline conditions with reduced asphaltenes in vacuum residues. The third scenario may include any combination of increased conversion and reduced asphaltenes in the bottoms product and may be dependent on feedstock quality (e.g. scale tendencies) which may be variable, equipment fouling rate and/or desired bottoms product quality, which will be used as a petroleum fuel or other end product.

In some embodiments, the vacuum residues may be recycled at a recycle ratio of from about 1% to about 50%, preferably from about 5% to about 40%, and more preferably from about 10% to about 30%. The recirculation ratio can be expressed as a percentage, determined by the ratio of the recycled amount of vacuum residues to the amount of fresh raw materials, either in volume or mass terms. These percentages indicate the vacuum residue flow rate as a volume percentage of the fresh feed flow rate. The recirculation ratio can also be easily converted to a mass fraction in percent if the densities of the feedstock and vacuum residues are known.

In some embodiments of the invention, the recycling of vacuum residues without the buildup of recycled asphaltenes in the vacuum residues leads to an increase in the rate of production of converted products compared to the initial conditions. In some embodiments of the invention, productivity can be increased by at least 2.5%, at least 5%, at least 10%, or at least 20% compared to baseline. In some embodiments of the invention, the conversion can be increased by

- 2 041453 at least 2.5%, at least 5%, at least 7.5%, at least 10% or at least 15% compared to the initial conditions. In some embodiments of the invention, the operating temperature of the improved fluidized bed reactor can be increased by at least 2.5°C, at least 5°C, at least 7.5°C, or at least

10°C compared to baseline.

In some embodiments of the invention, the fouling rate of the equipment may be the same or less when operating an improved fluidized bed reactor with recirculation of vacuum residues compared to the initial conditions. In some embodiments of the invention, the operation of the fluidized bed reactor with recirculation of vacuum residues can reduce the rate of equipment fouling by at least 5%, at least 25%, at least 50%, or at least 75% compared to equipment fouling. in initial conditions.

The fouling rate of the equipment can be measured by at least one of the following: (i) the frequency of required heat exchanger cleanings; (ii) frequency of switching to standby heat exchangers; (iii) frequency of filter replacement; (iv) frequency of cleaning or replacement of the coarse filter; (v) the rate of decrease in the temperature of the skin of the equipment, including equipment selected from heat exchangers, separators or distillation columns; (vi) the rate of temperature rise of the chimney metal; (vii) rate of increase in design fouling resistance factors for heat exchangers and furnaces; (viii) the rate of increase in pressure drop across the heat exchangers; (ix) the frequency of cleaning of atmospheric and/or vacuum distillation columns; or (x) the frequency of periods of maintenance and scheduled preventive maintenance.

In some embodiments, the particulate metal sulfide catalyst particles are less than 1 micron, less than 500 nm, less than 250 nm, less than 100 nm, less than 50 nm, or less than 25 nm, or less than about 10 nm, or less than about 5 nm.

In some embodiments, particulate metal sulfide catalyst particles may be formed in situ in heavy oil from a catalyst precursor. By way of example, and not limitation, particulate metal sulfide catalyst particles can be formed by mixing the catalyst precursor in total heavy oil to thermally decompose the catalyst precursor and form active metal sulfide catalyst particles. As a further example, the methods may include mixing the catalyst precursor with a hydrocarbon diluent to first form a dilute precursor mixture, followed by mixing the dilute precursor mixture with a heavy oil to form a conditioned heavy oil, and heating the conditioned heavy oil to decompose the catalyst precursor and form particles of dispersed metal sulfide catalyst into heavy oil in situ.

According to the formula, a method is provided for improving a hydroprocessing system with a fluidized bed of catalyst, which contains one or more fluidized bed reactors, including the following steps:

operating a fluidized bed reactor using a heterogeneous heavy oil hydroprocessing catalyst with initial conditions, the initial conditions including a rate that is related to the operating temperature, productivity, and conversion of said reactor;

adding or forming in situ particulate metal sulfide catalyst particles in a fluidized bed reactor to obtain an improved fluidized bed reactor with a two-way catalyst system consisting of a heterogeneous catalyst and particulate metal sulfide catalyst particles;

operating an improved fluidized bed reactor using a two-way catalyst system at the same or higher rate as compared to the corresponding rate of said fluidized bed reactor operating at baseline for hydroprocessing heavy oil to produce hydrocarbon products;

subjecting the obtained hydrocarbon products to one or more separation processes, including vacuum distillation and separation of distillates from vacuum residues containing residual metal sulfide catalyst particles; and recycling at least a portion of the resulting vacuum residues containing residual metal sulfide catalyst particles to said improved fluidized bed reactor such that the concentration of asphaltenes in said fluidized bed hydroprocessing system remains at the same or lower level, wherein the vacuum residues are recycled at a rate recirculation from 1 to 50%, characterizing the ratio of the flow rate of recycled vacuum residues to the flow rate of fresh heavy oil added to the improved fluidized bed reactor, expressed as a percentage by volume.

Preferably, the operation of the improved fluidized bed reactor includes

- 3 041453 operation at a higher conversion than the conversion under the original conditions, while not causing the buildup of recycled asphaltenes in the vacuum residues, and the higher conversion is chosen so as to increase the rate of production of conversion products compared to the initial conditions without increasing equipment fouling and/ or without reducing the quality of the bottom product.

Preferably, operation of the improved fluidized bed reactor includes operation at a similar conversion as the baseline conversion and with reduced asphaltenes in the vacuum residues, wherein operation of the improved fluidized bed reactor at a similar conversion maintains a rate of production of conversion products relative to baseline while reducing equipment fouling. and/or when improving the quality of the bottom product.

Preferably, operation of the improved fluidized bed reactor includes operation at a higher conversion than baseline conversion and with reduced asphaltene concentration in vacuum residues, the higher conversion being chosen to increase the rate of production of conversion products over baseline while reducing equipment fouling. and/or when improving the quality of the bottom product.

Preferably, the vacuum residues are recycled at a recycle ratio of 5 to 40%, or 10 to 30%, depending on the flow rate of the recycled vacuum residues as a volume percentage of the flow rate of the fresh heavy oil added to the improved fluidized bed reactor.

Preferably, the operation of the improved fluidized bed reactor using a two-way catalyst system is carried out at a similar or higher temperature than the initial conditions, such as the temperature of the improved fluidized bed reactor increased by at least 2.5°C, at least 5°C , at least 7.5°C or at least 10°C compared to the operating temperature of the fluidized bed reactor under initial conditions.

Preferably, the improved fluidized bed reactor is operated using a two-way catalyst system at a similar or higher conversion than the baseline conversion, such as when the improved fluidized bed reactor is operated at a conversion that is increased by at least 2.5%, at least by at least 5%, at least 7.5%, at least 10%, or at least 15% compared to the conversion when the fluidized bed reactor is operated under baseline conditions.

Preferably, the operation of the improved fluidized bed reactor using a two-way catalyst system is carried out at a similar or higher productivity compared to the productivity under the initial conditions, such as the productivity when the improved fluidized bed reactor is operated at a productivity that is increased by at least 2.5%, according to by at least 5%, at least 10%, or at least 20% compared to the conversion when the fluidized bed reactor is operated under initial conditions.

Preferably, operation of the improved fluidized bed reactor using a two-way catalyst system involves hydroprocessing heavy oil having a lower quality, e.g., having a higher concentration of asphaltene compared to baseline heavy oil hydroprocessing, so that the concentration of asphaltene in the low quality heavy oil that has undergone hydroprocessing through an advanced fluidized bed reactor is at least 2%, at least 5%, at least 10%, at least 15%, or at least 20% higher than the concentration of asphaltenes in heavy oil, which was hydroprocessed by an advanced fluidized bed reactor while operating under baseline conditions.

Preferably, the improved fluidized bed reactor hydroprocesses asphaltenes at an asphaltene conversion that is at least 2% higher, at least 5% higher, at least 10% higher, at least 15% higher, or at least 20% higher. % higher compared to the conversion of asphaltenes when the operation of the fluidized bed reactor occurs under the initial conditions.

Preferably, the operation of the improved fluidized bed reactor is provided under conditions that the fouling rate of the equipment is not higher than the fouling rate of the equipment during the operation of the fluidized bed reactor in the initial conditions, and preferably the operation of the improved fluidized bed reactor is provided under the conditions that the fouling rate of the equipment is lower than the fouling rate equipment during the operation of the fluidized bed reactor in the initial conditions, and the operation of the improved fluidized bed reactor is provided under conditions that reduce the fouling rate of the equipment by at least 5, 25, 50 or 75% compared to the fouling rate of the equipment during the operation of the reactor fluidized bed under initial conditions.

Preferably, the equipment fouling rate is determined by at least one of the following:

(i) frequency of required heat exchanger cleanings;

(ii) frequency of switching to standby heat exchangers;

(iii) frequency of filter replacement;

(iv) frequency of cleaning or replacement of the coarse filter;

(v) the rate of decrease in the temperature of the skin of the equipment, including equipment selected from heat exchangers, separators or distillation columns;

(vi) the rate of temperature rise of the chimney metal;

(vii) rate of increase in design fouling resistance factors for heat exchangers and furnaces;

(viii) the rate of increase in pressure drop across the heat exchangers;

(ix) the frequency of cleaning of atmospheric and/or vacuum distillation columns; or (x) the frequency of periods of maintenance and scheduled preventive maintenance.

Preferably, the heavy oil includes at least one of heavy crude oil, oil sand bitumen, process plant bottoms, atmospheric column bottoms having a nominal boiling point of at least 343°C (650°F), vacuum tower bottoms having a nominal boiling point of at least 524°C (975°F), hot separator residue, resin residue, solvent extraction residue, or vacuum residue.

Preferably, the particulate metal sulfide catalyst particles are less than 1 µm, or less than 500 nm, or less than 250 nm, or less than 100 nm, or less than 50 nm, or less than about 25 nm, or less than about 10 nm.

Preferably, the improvement of the fluidized bed reactor for operation using a two-way catalyst system includes the formation of particles of the dispersed metal sulfide catalyst in situ inside the heavy oil from the catalyst precursor, and, in particular, the formation of particles of the dispersed metal sulfide catalyst in situ inside the heavy oil includes mixing the catalyst precursor with a carbon diluent for forming a dilute precursor mixture, mixing the dilute precursor mixture with the heavy oil to form a conditioned heavy oil, and heating the conditioned heavy oil to decompose the catalyst precursor and form dispersed metal sulfide catalyst particles in situ within the heavy oil.

Preferably, the operation of the fluidized bed reactor using a heterogeneous heavy oil hydroprocessing catalyst at baseline includes recirculation of vacuum residues and buildup of recycled asphaltenes.

These and other advantages and characteristics of the present invention will be more fully apparent from the following description and the appended claims, or may be learned from the practice of the invention as set forth hereinafter.

Brief description of graphic materials

To further highlight the above and other advantages and characteristics of the present invention, a more detailed description of the invention will be made with reference to its individual embodiments, which are illustrated in the accompanying drawings. Obviously, these drawings illustrate only typical embodiments of the invention and therefore are not considered as limiting its scope. The invention will be described and explained with further certainty and detail by reference to the accompanying drawings, in which:

in fig. 1 shows a hypothetical molecular structure of asphaltene;

in fig. 2A and 2B are schematic illustrations of exemplary fluidized bed reactors;

in fig. 2C schematically illustrates an exemplary fluidized bed hydroprocessing system comprising a plurality of fluidized bed reactors and recirculating vacuum column bottoms;

in fig. 2D schematically illustrates an exemplary fluidized bed hydroprocessing system comprising a plurality of fluidized bed reactors similar to that shown in FIG. 2C, and an intermediate separator between the two reactors;

in fig. 3A is a flow diagram illustrating an exemplary process for improving a fluidized bed reactor for recirculating vacuum residues without building up recycled asphaltenes in the vacuum residues;

in fig. 3B is a flow diagram illustrating an exemplary process for upgrading a vacuum bottoms recycle fluidized bed reactor with higher conversion than baseline and no buildup of recycled asphaltenes in the vacuum bottoms;

- 5 041453 in FIG. 3C is a flow diagram illustrating an exemplary process for upgrading a fluidized bed reactor for recirculating vacuum residues with a similar conversion compared to baseline and reduced asphaltenes in the vacuum residues;

in fig. 3D is a flow diagram illustrating an exemplary process for upgrading a fluidized bed reactor for recirculating vacuum residues with higher conversion than baseline and reduced asphaltenes in the vacuum residues;

in fig. 4 schematically illustrates an exemplary fluidized bed hydroprocessing system using a two-way catalyst system;

in fig. 5 schematically illustrates a laboratory scale fluidized bed hydroprocessing system configured to use either a single heterogeneous catalyst or a two-way catalyst system comprising a heterogeneous catalyst and dispersed metal sulfide particles;

in fig. 6 is a line graph illustrating C7 asphaltene content as a function of residue conversion for each of Examples 16, including at baseline using a heterogeneous catalyst and during operation of an improved fluidized bed reactor using a two-way catalyst system;

in fig. 7 is a line graph illustrating embodiments of the invention in which an improved fluidized bed reactor using a two-way catalyst system operates at a higher conversion than baseline without buildup of recycled asphaltenes in vacuum bottoms;

in fig. 8 is a line graph illustrating embodiments of the invention in which an improved fluidized bed reactor using a two-way catalyst system operates at a similar conversion compared to baseline conditions with reduced asphaltenes in vacuum residues;

in fig. 9 is a line graph illustrating embodiments of the invention in which an improved fluidized bed reactor using a two-way catalyst system operates at a higher conversion compared to baseline conditions with reduced asphaltenes in vacuum residues; and in FIG. 10 is a line graph illustrating other embodiments of the invention in which an improved fluidized bed reactor using a two-way catalyst system operates at a higher conversion than baseline with reduced asphaltenes in vacuum bottoms.

Detailed description of the preferred embodiments of the invention

I. Introduction and definitions

The present invention relates to methods for improving a hydroprocessing system in a fluidized bed of a catalyst to allow recirculation of vacuum residues without buildup of recycled asphaltenes (for example, in a hydroprocessing system such as a fluidized bed reactor and/or vacuum residues). An improved fluidized bed processing system is created by implementing the disclosed method.

The terms asphaltene and asphaltenes refer to materials in heavy oil feedstocks that are generally insoluble in paraffinic solvents such as propane, butane, pentane, hexane and heptane. Asphaltenes may contain layers of condensed ring compounds held together by heteroatoms, such as sulfur, nitrogen, oxygen, and metals. Broadly speaking, asphaltenes include a wide range of complex compounds having from 80 to 1200 carbon atoms, with predominant molecular weights, determined by solution methods, ranging from 1200 to 16900. About 80-90% of the metals in heavy oils are contained in the asphaltene fraction, which, together with a higher concentration of non-metallic heteroatoms, makes the asphaltene molecules more hydrophilic and less hydrophobic than other hydrocarbons in their raw form.

In FIG. 1 illustrates a hypothetical asphaltene molecule structure developed by AG Bridge and co-workers at Chevron. In general, asphaltenes are usually determined based on the results of insolubles determination methods, and more than one determination of asphaltenes may be used. In particular, the commonly used definition of asphaltenes is heptane-insoluble impurities without toluene-insoluble impurities (i.e., asphaltenes are toluene-soluble); deposits and residues insoluble in toluene are not considered asphaltenes). Asphaltenes thus defined may be referred to as C ₇ -asphaltenes. However, with equal validity, an alternative definition given as pentane-insoluble impurities without toluene-insoluble impurities, commonly referred to as C ₅ -asphaltenes, may be used. In the examples of the present invention, the definition of C ₇ -asphalten is used, and the definition of C ₅ -asphalten can be easily changed.

The term build-up of recycled asphaltenes refers to situations in which the recirculation of vacuum residues back to the fluidized bed reactor results in an increase in the concentration of asphaltenes in the hydroprocessing system in the fluidized bed of the catalyst, such as the fluidized bed reactor and/or the vacuum residues. For example, for any given reactor operating conditions such as conversion, temperature and/or throughput, re-deposition of asphaltenes during recycle of vacuum residues means that the concentration of asphaltenes increases even when the degree of processing remains constant due to the increased concentration of asphaltenes in vacuum residues over compared to heavy oil feedstock. In such cases, the fluidized bed reactor is not able to effectively hydroprocess and convert additional asphaltenes at a high enough rate to prevent buildup of recycled asphaltenes. This results in increased scale buildup and equipment fouling, more frequent shutdowns for cleaning, and lower quality vacuum residues. An increase in recycled asphaltenes may indicate an increased equilibrium concentration of asphaltenes.

The use of an improved fluidized bed reactor with recirculation of vacuum residues without buildup of recycled asphaltenes means that the asphaltene content of the hydroprocessing system in the fluidized bed of the catalyst, including the fluidized bed reactor, remains at the same or lower level than in the case of no recirculation. In some cases, the asphaltene concentration may even drop when operating at a similar conversion from baseline, or even at a higher conversion, when vacuum residues are recycled to an improved fluidized bed reactor with a two-way catalyst system. This is unexpected since higher conversion generally results in more deposit formation and equipment fouling, all other things being equal.

The term deposit refers to solids formed in a fluid stream that can be deposited. The deposits may contain inorganic matter, coke residue or insoluble asphaltenes that are deposited after processing. Deposition in petroleum products is typically measured using the IP-375 Hot Filterability Test Procedure for Total Deposition in Residual Fuel Oils published in accordance with ISO 10307 and ASTM D4870. Other tests include the IP-390 deposit test and the hot filterability test of body parts. The deposit is associated with oil components that tend to form solids during processing and transportation. These solids-forming components have undesirable effects in the hydroconversion process in many respects, including degradation of product quality (eg, vacuum residue quality) and serviceability problems associated with equipment fouling. It should be noted that although the narrow definition of deposit is based on the measurement of solids in a deposit containing test, the term is generally used more broadly to refer to the solids-forming components of the oil itself, which may not be present as actual solids in the oil, but which contribute to the formation of solids under certain conditions.

All heavy oils contain a vacuum fuel oil component which has a characteristic tendency to form deposits. While the scaling tendency inherent in heavy oil feedstocks is not always quantifiable, some heavy oil feedstocks have less or more pronounced scaling tendencies, such as heavy oils from Eastern European regions, heavy oils from South America, such as Venezuela and Colombia, as well as some types of heavy oil from the regions of Central or North America, such as Mexico; and some heavy oils in the Gulf of Mexico contain vacuum fuel oil components that have a significantly higher tendency to deposit than conventional heavy oils such as West Texas medium heavy oils, Alaska North Slope heavy oils, many African heavy oils, oils, North Sea heavy oils, and most Middle Eastern heavy oils, including Arabian heavy oils, Arabian heavy oils, and bonny light crudes.

The term fouling refers to the formation of an undesirable phase (contaminant) that interferes with processing. The contaminant is typically a carbonaceous material or solid that is deposited and collected in the processing equipment. Equipment fouling can lead to production shutdowns due to equipment shutdown, reduced equipment performance, increased energy consumption due to the insulating effect of fouling deposits in heat exchangers or heaters, increased operating costs for cleaning equipment, decreased efficiency of distillation plants, and reduced chemical activity heterogeneous catalyst.

The degree of fouling of equipment before and after upgrading the hydrocracking reactor for the application of a two-way catalyst system can be determined by at least one of the following: (i) the frequency of necessary cleaning of the heat exchanger; (ii) frequency of switching to standby heat exchangers; (iii) frequency of filter replacement; (iv) frequency of cleaning or replacement of the coarse filter; (v)

- 7 041453 the rate of decrease in the temperature of the casing of the equipment, including equipment selected from heat exchangers, separators or distillation columns; (vi) the rate of temperature rise of the chimney metal; (vii) rate of increase in design fouling resistance factors for heat exchangers and furnaces; (viii) the rate of increase in pressure drop across the heat exchangers; (ix) the frequency of cleaning of atmospheric and/or vacuum distillation columns; or (x) the frequency of periods of maintenance and scheduled preventive maintenance.

The term heavy oil feedstock refers to heavy crude oil, oil sand bitumen, sludge and plant residues (e.g. visbreaking residues) and any other lower quality materials that contain significant amounts of high-boiling hydrocarbon fractions and/or or which contain a significant amount of asphaltenes, which can deactivate the heterogeneous catalyst and/or cause or lead to the formation of coke precursors and deposits. Examples of heavy oil feedstocks include, but are not limited to, Lloydminster heavy oil, cold lake bituminous oil, Athabasca bitumens, atmospheric tower residues, vacuum tower residues, sediments (or residues), resin residues, vacuum residues (e.g. Ural Vacuum Residue, Arabian Medium Vacuum Residue, Athabasca Bituminous Residue, Cold Lake Vacuum Residue, Maya Vacuum Residue, and Chichimene Oil Vacuum Residue), solvent deasphalted fluids, asphaltene fluids, obtained as a by-product of deasphalting, and fractions of non-volatile liquids that remain after the processing of heavy oil, bituminous heavy oil from tar sands, liquefied coal, oil shale or coal tar feedstock by distillation, hot separation, solvent extraction, etc. similar. As an additional example, the nominal boiling point of the bottoms atmospheric column (OAK) can be at least 343°C (650°F), although it should be understood that the boundary temperature of separation of the distillation fraction may vary depending on refineries and should be up to 380 °C (716°F). The nominal boiling point of the bottoms of the vacuum column can be at least 524°C (975°F), although it should be understood that the boundary temperature of the separation of the distillation fraction may vary depending on the refinery and can be up to 538°C (1000°F) or even 565°C (1050°F).

The quality of a heavy oil can be determined by at least one property selected from, without limitation, the following: (i) boiling point; (ii) sulfur concentration; (iii) nitrogen concentration; (iv) concentration of metals; (v) molecular weight; (vi) hydrogen to carbon ratio; (vii) asphaltene content; and (viii) scaling tendency.

The lower quality heavy oil and/or the lower quality feed blend may have at least one lower quality characteristic compared to the heavy oil feedstock, selected without limitation from the following: (i) higher boiling point; (ii) higher sulfur concentration; (iii) higher nitrogen concentration; (iv) higher concentration of metals; (v) higher molecular weight (often referred to as higher density and viscosity); (vi) lower hydrogen to carbon ratio; (vii) higher asphaltene content; and (viii) greater tendency to deposit.

The term potential feedstock refers to lower quality heavy oils and lower quality heavy oil feedstock blends having at least one lower quality characteristic compared to heavy oil feedstocks. In addition, the potential feedstock has a lower market value (or price) than the feedstock.

The terms hydrocracking and hydrorefining refer to a process whose primary purpose is to lower the boiling range of a heavy oil feedstock and in which a significant portion of the feedstock is processed into products with lower boiling ranges than the feedstock. Hydrocracking or hydroprocessing basically involves the fragmentation of larger hydrocarbon molecules into smaller molecular fragments with fewer carbon atoms and a higher ratio of hydrogen to carbon. The mechanism by which hydrocracking occurs typically involves the generation of hydrocarbon-free radicals during thermal fragmentation followed by capping of the ends or fragments of the free radical molecules with hydrogen. Hydrogen atoms or radicals that react with non-hydrocarbon radicals during hydrocracking can be formed at or with the help of catalyst active sites.

The term hydrotreating refers to operations whose primary purpose is to remove impurities such as sulfur, nitrogen, oxygen, halides and trace metals from feedstocks and saturated olefinic hydrocarbons and/or to stabilize hydrocarbon-free radicals by reacting them with hydrogen instead of to allow them to interact with each other. The main goal is not to change the boiling range of the raw material. Most often, hydroprocessing is carried out using a fixed bed reactor, although for hydroprocessing

- 8 041453 it is also possible to use other hydroprocessing reactors, an example of which is a fluidized bed hydrotreater.

Of course, hydrocracking or hydroprocessing can also include the removal of sulfur and nitrogen from feedstocks, as well as saturation of olefins and other reactions typically associated with hydroprocessing. The terms hydroprocessing and hydroprocessing broadly refer to both hydrocracking and hydrotreating processes that define opposite ends of the spectrum and everything in between across the spectrum.

The term hydrocracking reactor refers to any vessel whose primary purpose is to hydrocrack (ie, reduce the boiling range) of a feedstock in the presence of hydrogen and a hydrocracking catalyst. Hydrocracking reactors are characterized by having an inlet into which a heavy oil feed and hydrogen can be introduced, an outlet from which an improved feed or material can be recovered, and sufficient thermal energy to form hydrocarbon-free radicals to cause more fragmentation. large hydrocarbon molecules into smaller molecules. Examples of hydrocracking reactors include, but are not limited to, slurry phase reactors (i.e. two-phase gas-liquid system), fluidized bed reactors (i.e. three-phase gas-liquid-solid system), fixed bed reactors (i.e., a three-phase system that involves feeding liquid flowing down over or flowing up through a fixed bed of a solid heterogeneous catalyst with hydrogen, usually flowing in parallel (but possibly countercurrent), into the heavy oil).

The term hydrocracking temperature refers to the minimum temperature required to initiate significant hydrocracking of heavy oil feedstocks. Typically, hydrocracking temperatures are preferably in the range from about 399°C (750°F) to about 460°C (860°F), more preferably in the range from about 418°C (785°F) to about 443°C (830 °F), and most preferably in the range from about 421°C (790°F) to about 440°C (825°F).

The term gas-liquid slurry-phase hydrocracking reactor refers to a hydroprocessing reactor that contains a continuous liquid phase and a gaseous dispersed phase that forms a suspension of gas bubbles in the liquid phase. The liquid phase typically contains a hydrocarbon feed, which may contain a low concentration of particulate metal sulfide catalyst particles, and the gaseous phase typically contains hydrogen gas, hydrogen sulfide, and vaporized low-boiling hydrocarbon products. The liquid phase may optionally contain a hydrogen donor solvent. The term three-phase gas-liquid-solid slurry hydrocracking reactor is used when a solid catalyst is used together with liquid and gas. The gas may contain hydrogen, hydrogen sulfide and vaporized low boiling hydrocarbon products. The term slurry phase reactor broadly refers to both types of reactors (eg, particulate metal sulfide catalyst particle reactors, micron or larger particle catalyst reactors, and reactors that contain both).

The terms solid heterogeneous catalyst, heterogeneous catalyst and supported catalyst refer to catalysts commonly used in fluidized bed and fixed bed hydroprocessing systems, including catalysts primarily for hydrocracking, hydroprocessing, hydrodemetallization and/or hydroprocessing. A heterogeneous catalyst typically comprises: (i) a catalyst support having a large surface area and interconnected channels or pore channels; and (ii) fine active catalyst particles such as cobalt, nickel, tungsten and molybdenum sulfides dispersed within the channels or pore channels. The pore channels of the carrier are usually of limited size to maintain the mechanical integrity of the heterogeneous catalyst and to prevent segregation and the formation of excess fines in the reactor. Heterogeneous catalysts can be obtained as cylindrical pellets, cylindrical extrudates, other shapes such as trefoils, rings, saddles, and the like, or spherical solids.

The terms particulate metal sulfide catalyst particles and particulate catalyst refer to catalyst particles having a diameter of less than 1 μm (less than a micron or less than a micrometer), for example, less than about 500 nm in diameter, or less than about 250 nm in diameter, or less than about 100 nm in diameter. diameter, or less than about 50 nm in diameter, or less than about 25 nm in diameter, or less than about 10 nm in diameter, or less than about 5 nm in diameter. The term particulate metal sulfide catalyst particles may include molecular or molecularly dispersed catalyst compounds. The term particulate metal sulfide catalyst particles generally excludes metal sulfide particles and accumulations of metal sulfide particles larger than 1 micron.

The term molecularly dispersed catalyst refers to catalyst compounds that are substantially dissolved or dissociated from other catalyst compounds or molecules in a hydrocarbon feed or a suitable diluent. It may include very fine catalyst particles that contain several catalyst molecules linked together (eg, 15 molecules or less).

The terms residual catalyst particles and residual dispersed metal sulfide catalyst particles refer to catalyst particles that remain in the hydrocarbon product when transferred from one vessel to another (for example, from a hydroprocessing reactor to a separator and/or another hydroprocessing reactor). Residual dispersed metal sulfide catalyst particles can also remain in the liquid bottom fraction after separation of the hydrocarbon product into distillates and bottom liquid, for example by hot separation, atmospheric distillation or vacuum distillation.

The term "conditioned feed" means a hydrocarbon feed in which the catalyst precursor has been combined and mixed sufficiently such that after the catalyst precursor has decomposed and formed an active catalyst, the catalyst will contain dispersed metal sulfide catalyst particles formed in situ within the feed.

The terms enrich, enrich, and enriched, when used to describe a feedstock that is or has been hydroprocessed, or the resulting material or product, refer to one or more of the following: feedstock molecular weight reduction, feedstock boiling range reduction, asphaltene reduction, hydrocarbon concentration reduction free radicals and/or reduction of impurities such as sulfur, nitrogen, oxygen, halides and metals.

The term rate essentially refers to the amount of energy that is applied to the heavy oil during hydroprocessing, and often refers to the operating temperature of the hydroprocessing reactor (i.e. higher temperature is associated with higher intensity; lower temperature is associated with lower degree of intensity) in combination with the duration of the indicated temperature exposure.

An increased degree of intensity substantially increases the amount of conversion products produced by the hydroprocessing reactor, including both desirable products and undesirable products.

Desirable refinery products include hydrocarbons of reduced molecular weight, boiling point, and specific gravity, which may include commercial products such as naphtha, diesel fuel, jet fuel, kerosene, wax, fuel oil, and the like. Other desirable processed products include high-boiling hydrocarbons, which can be further processed using conventional processing and/or distillation processes. Another example of a desired refined product is a bottoms product of sufficient quality suitable for use as a fuel oil.

Undesirable by-products include coke, deposits, metals, and other solid materials that can deposit on hydroprocessing equipment and lead to fouling, for example, on reactor internals, separators, filters, pipes, columns, heat exchangers, and heterogeneous catalysts. Undesired by-products may also refer to the unconverted residue that remains after distillation, such as atmospheric column residues (OER) or vacuum column residues (VCR), in particular those that are of too low a quality to be useful as a fuel oil or for other required application. Minimizing unwanted by-products reduces clogging and equipment downtime required to clean equipment. However, there may be a desired amount of unconverted residue in order for the downstream separation equipment to function properly and/or to provide a liquid transport medium for storing coke, deposits, metals and other solids that might otherwise be deposited on the equipment. and clog it, but which can be withdrawn using the available residue.

In addition to temperature, intensity can be related to one or both of conversion and throughput. Whether the increase in intensity will include an increase in conversion and/or an increase or decrease in productivity may depend on the quality of the heavy oil feedstock and/or the weight ratio in the overall hydroprocessing system. For example, if more feed is to be processed and/or more material is to be provided to downstream equipment, the increased rate may primarily include an increase in productivity without the need to increase the conversion. This may include the case where bottoms fractions (UAC and/or HVAC) are sold as fuel oils and an increase in conversion without an increase in productivity could reduce the amount of this product. In the case where it is desired to increase the ratio of enriched materials to bottoms fractions, it may be desirable to mainly increase the conversion without the need to increase productivity. In cases where the quality of the heavy oil introduced into the hydroprocessing reactor fluctuates, it may be desirable to selectively increase or decrease one or both of the conversion and throughput in order to maintain the desired ratio of enriched materials to bottoms fractions and/or the required absolute amount or absolute amounts of product. final product (final products obtained).

The terms conversion and degree of conversion refer to the relative content, often

- 10 041453 expressed as a percentage, heavy oil, which is processed into materials with a lower boiling point and/or lower molecular weight. The conversion is expressed as a percentage of the original residue content (i.e. components with a boiling point above a certain distillation cut-off point) that is converted into products with a boiling point below a certain cut-off point. The definition of cutoff temperature may vary and may nominally include 524°C (975°F), 538°C (1000°F), 565°C (1050°F) and the like. It can be measured by analyzing the distillation of feed and product streams to determine the concentration of components with a boiling point above a certain cut-off temperature. The conversion is expressed as (F-P)/F where F is the amount of bottoms in the combined feed streams and P is the amount in the combined product streams, with both the bottoms content of both the feed and product based on the same definition of the boundary temperature of fraction separation. The amount of bottoms is most often determined based on the mass of components with a boiling point above a certain cut-off temperature, and volumetric or molar determinations can also be used.

The conversion of asphaltenes may differ from that of heavy oil feedstocks in general. For the purposes of this invention, a suitable definition of asphaltene conversion is based on the amount of asphaltenes in fresh feed and can be determined by the following equation, which results in a fraction between 0 and 1, which can be converted to a percentage by multiplying by 100:

Conv. \u003d [asph. (fresh raw materials) - asph. (products)] / asph. (fresh raw materials).

The content of asphaltenes in the recycle stream is internal to the process. When the conversion of asphaltenes is too low compared to the conversion of a large amount of heavy oil in general, a build-up of recycled asphaltenes can occur.

The term productivity refers to the amount of feed material that is introduced into the hydroprocessing reactor as a function of time. Productivity can be expressed in volumetric units, such as barrels per day, or mass units, such as metric tons per hour. In common use, productivity is defined as the mass or volumetric feed rate of only the heavy oil feedstock itself (eg, vacuum tower residues, etc.). This definition generally does not include amounts of diluents or other components that may sometimes be included in the total feed to the hydroprocessor, although a definition that includes these other components may be used.

The rate of production of conversion products is an absolute rate, which can be expressed in volumetric units, such as barrels per day, or mass units, such as metric tons per hour. The rate of production of conversion products should not be confused with output or efficiency, which is sometimes erroneously referred to as rate (for example, rate of production per unit of feed rate or rate of production per unit of raw material converted). It should be understood that the actual numerical values of both the initial rate of production of conversion products and the increased rate of production of conversion products are characteristic of individual production facilities and depend on the productivity of these facilities. Thus, it is perfectly acceptable to compare the production rate of the device or object in question before and after the improvement, but it is not acceptable to compare it with another device or object built with a different productivity.

II. Fluidized bed hydroprocessing reactors and systems

In FIG. 2A-2D are schematic non-limiting examples of fluidized bed hydroprocessing reactors and systems used to hydroprocess hydrocarbon feedstocks, such as heavy oils, that can be upgraded to use the two-way catalyst system in accordance with the present invention. It should be understood that exemplary fluidized bed hydroprocessing reactors and systems may include intermediate separation, integrated hydrotreatment, and/or integrated hydrocracking.

In FIG. 2A is a schematic representation of a fluidized bed hydroprocessing reactor 10 used in the LC-Fining hydrocracking system developed by C-E Lummus. The fluidized bed reactor 10 has an inlet 12 near the bottom through which the feedstock 14 and compressed hydrogen gas 16 are introduced, and an outlet 18 at the top through which the hydroprocessed material 20 is withdrawn.

The reactor 10 further comprises an expanded catalyst containing zone 22 containing a heterogeneous catalyst 24 that is held in an expanded or fluidized state with respect to gravity by moving upwardly liquid hydrocarbons and gas (shown schematically as bubbles 25) through the fluidized bed reactor 10. The lower end of the expanded catalyst zone 22 is defined by a distribution grid plate 26 which separates the expanded catalyst zone 22 from the lower heterogeneous catalyst-free zone 28 located at the

- 11 041453 waiting for the lower part of the fluidized bed reactor 10 and the distribution grid plate 26. The distribution grid plate 26 is designed to evenly distribute hydrogen gas and hydrocarbons throughout the reactor and prevent the heterogeneous catalyst 24 from falling under gravity into the lower zone 28 that does not contain heterogeneous catalyst. The upper end of the expanded catalyst zone 22 is at a height at which downward gravity begins to equal or exceed the uplift force of the upwardly moving feed and gas through the fluidized bed reactor 10 as the heterogeneous catalyst 24 reaches a predetermined level of expansion or separation. The above extended catalyst zone 22 is an upper zone 30 containing no heterogeneous catalyst.

Hydrocarbons and other materials within the fluidized bed reactor 10 are constantly recycled from the upper zone 30 containing no heterogeneous catalyst to the lower zone 28 containing no heterogeneous catalyst via a recirculation channel 32 centrally located in the fluidized bed reactor 10 connected to an ebullation pump 34 at the bottom of the fluidized bed reactor 10. At the top of the recirculation channel 32 is a funnel-shaped recirculation bowl 36 through which feed is supplied from the upper zone 30 that does not contain heterogeneous catalyst. The material drawn down through the recirculation channel 32 enters the lower catalyst-free zone 28 and then passes upward through the distribution grid plate 26 to the expanded catalyst zone 22 where it mixes with the freshly added feed 14 and hydrogen gas 16 entering the reactor 10 fluidized bed through inlet 12. The constant upward circulation of mixed materials through the fluidized bed reactor 10 advantageously maintains the heterogeneous catalyst 24 in an expanded or fluidized state within the expanded catalyst zone 22, minimizes channeling, controls reaction rates, and conserves heat released by exothermic reactions hydrogenation, at a safe level.

Fresh heterogeneous catalyst 24 is introduced into the fluidized bed reactor 10, for example into the expanded catalyst zone 22, via a catalyst inlet tube 38 which extends through the top of the fluidized bed reactor 10 directly into the expanded catalyst zone 22. The spent heterogeneous catalyst 24 is withdrawn from the expanded catalyst zone 22 through a catalyst recovery tube 40 that extends from the lower end of the expanded catalyst zone 22 through the distribution grid plate 26 and the bottom of the fluidized bed reactor 10. It should be understood that catalyst recovery tube 40 cannot distinguish between fully spent catalyst, partially spent but active catalyst, and freshly added catalyst, so a random distribution of heterogeneous catalyst 24 is typically recovered from fluidized bed reactor 10 as spent catalyst.

The enriched hydrocarbon material 20 withdrawn from the fluidized bed reactor 10 may be introduced into a separator 42 (eg, a hot separator, an intermediate pressure swing separator, an atmospheric distillation column, or a vacuum distillation column). A separator 42 separates one or more volatile fractions (or distillates) 46 from non-volatile fractions (or liquid) 48.

In FIG. 2B schematically illustrates a fluidized bed reactor 110 used in the H-Oil hydrocracking system developed by Hydrocarbon Research Incorporated and currently used under license from Axens. The fluidized bed reactor 110 includes an inlet 112 through which heavy oil feed 114 and compressed hydrogen gas 116 are introduced, and an outlet 118 through which enriched hydrocarbon material 120 is withdrawn. 126, which separates the expanded catalyst zone 122 from the lower catalyst-free zone 128 between the bottom of the reactor 110 and the distribution grid plate 126, as well as the upper end 129, which defines the approximate boundary between the expanded catalyst zone 122 and the upper zone 130, which does not contain catalyst. The dotted boundary line 131 schematically illustrates the approximate level of heterogeneous catalyst 124 when it is not in an expanded or fluidized state.

Materials are continuously recirculated within the fluidized bed reactor 110 via a recirculation channel 132 connected to an ebullation pump 134 located outside of the reactor 110. Materials are withdrawn via a funnel-shaped recirculation cup 136 from an upper catalyst-free zone 130. Recirculation cup 136 is spirally shaped to allow hydrogen bubbles 125 to be separated from recirculation 132 to prevent cavitation of ebullation pump 134. Recirculation 132 enters the lower catalyst-free zone 128 where it mixes with fresh feed 116 and hydrogen gas 118 and the mixture passes through the distribution grating plate 126 into the expanded zone 122 of the catalyst. Fresh catalyst 124 is introduced into the expanded catalyst zone 122 through the catalyst inlet tube 137, and spent catalyst 124 is withdrawn from the expanded catalyst zone 122 through the catalyst outlet tube 140.

The main difference between the H-Oil fluidized bed reactor 110 and the LC-Fining fluidized bed reactor 10 is the location of the ebullation pump. The ebullation pump 134 in the H-Oil reactor 110 is placed outside the reaction chamber. Recycling raw materials are introduced through the recirculator

- 12 041453 recirculation hole 141 in the lower part of the reactor 110. The recirculation hole 141 contains a distributor 143, which promotes uniform distribution of materials in the zone 128 that does not contain the catalyst. It is illustrated that the rich hydrocarbon material 120 is sent to a separator 142 (e.g., a hot separator, an intermediate differential pressure separator, an atmospheric distillation column, or a vacuum distillation column) that separates one or more volatile fractions (or distillates) 146 from a non-volatile fraction (or liquid). ) 148.

In FIG. 2C schematically illustrates a fluidized bed hydroprocessing system 200 comprising a plurality of fluidized bed reactors. The hydroprocessing system 200, exemplified by the LC-Fining or H-Oil hydroprocessing unit, may include three fluidized bed reactors 210 arranged in series to upgrade the feedstock 212. The feedstock 212 from surge tank 214 is pressurized, preheated, and introduced into the first reactor. 210a of the fluidized bed together with hydrogen gas 216, both of which are passed through respective heaters before being introduced into the reactor. Rich hydrocarbon material 220a from first fluidized bed reactor 210a is introduced along with additional hydrogen gas 216 into second fluidized bed reactor 210b. The enriched hydrocarbon material 220b from the second fluidized bed reactor 210b is introduced along with additional hydrogen gas 216 into the third fluidized bed reactor 210c.

It should be understood that one or more intermediate separators (not shown) may optionally be located between the first and second fluidized bed reactors 210a, 210b and/or the second and third fluidized bed reactors 210b, 210c to remove low-boiling fractions and gases from non-volatile fractions containing liquid hydrocarbons; and residual dispersed metal sulfide catalyst particles. It may be desirable to remove low boiling alkanes such as hexanes and heptanes, which are valuable fuel products but poor solvents for asphaltenes. The removal of volatile materials between multiple reactors improves the production of valuable products and increases the solubility of asphaltenes in the liquid hydrocarbon material fed to the downstream reactor(s). Both increase the efficiency of the entire hydroprocessing system.

The enriched hydrocarbon material 220c from the third fluidized bed reactor 210c is fed to a high temperature separator 242a which separates volatile and non-volatile fractions. The volatile fraction 246a passes through a heat exchanger 250 which removes the heat that is used to preheat the hydrogen gas 216 before it is fed to the first fluidized bed reactor 210a. The slightly cooled volatile fraction 246a is sent to a medium temperature separator 242b, which separates the remaining volatile fraction 246b from the resulting liquid fraction 248b, which is formed as a result of cooling by the heat exchanger 250. The remaining volatile fraction 246b is sent downstream to a low temperature separator 242c for further separation into a gaseous fraction 252c and the degassed liquid fraction 248c.

The liquid fraction 248a from the high temperature separator 242a is sent along with the produced liquid fraction 248b from the medium temperature separator 242b to the low temperature separator 242d, which separates the hydrogen-containing gas 252d from the degassed liquid fraction 248d, which together with the degassed liquid fraction 248c from the low temperature separator 242c is sent to the tail system 260 , which contains one or more distillation columns, including a vacuum distillation column, where the materials are fractionated to produce products 262 and a recirculating vacuum column bottoms stream 264. The vacuum column bottoms recycle stream 264 may contain some or all of the vacuum column bottoms produced by tail system 260, with a portion of the vacuum column bottoms optionally removed as products 262 and not recycled.

The gaseous fraction 252c from the low temperature separator 242c is scrubbed to produce off-gas, purge gas, and hydrogen gas 216. Hydrogen gas 216 is compressed, mixed with hydrogen gas 216a, and either passed through heat exchanger 250 and introduced into first fluidized-bed reactor 210a along with feed 216, or injected directly into the second and third fluidized bed reactors 210b and 210b.

In FIG. 2D schematically illustrates a fluidized bed hydroprocessing system 200 that includes a plurality of fluidized bed reactors and is similar to the system illustrated in FIG. 2C, but showing an intermediate separator 221 located between the second and third reactors 210b, 210c (although an intermediate separator 221 (or other separator) may be located between the first and second reactors 210a, 210b). As illustrated, the effluent from the second stage reactor 210b enters an intermediate separator 221, which may be a high temperature high pressure separator. The liquid fraction from separator 221 is combined with a portion of the hydrogen recycle from line 216 and then enters third stage reactor 210c. The vapor fraction from the intermediate separator 221 bypasses the third stage reactor 210c, mixes with the effluent from the third stage reactor 210c, and then passes into the high temperature high pressure separator 242a.

This allows the lighter and richer components formed in the first two stages of the reactors to bypass the third stage reactor 210c. The advantages of this process are:

(1) reducing the steam load on the third stage reactor, which increases the utilization of the third stage reactor volume for processing the remaining heavy components, and (2) reducing the concentration of anti-solvent components (saturates) that can destabilize (e.g., precipitate) asphaltenes in the 210c reactor third step.

In preferred embodiments, the hydroprocessing systems are configured and operated to promote hydrocracking reactions rather than less intense hydroprocessing reactions such as hydroprocessing. Hydrocracking involves the breaking of carbon-carbon molecular bonds, such as reducing the molecular weight of larger hydrocarbon molecules and/or opening the ring of aromatic compounds. On the other hand, hydroprocessing predominantly involves the hydrogenation of unsaturated hydrocarbons with little or no degradation of the carbon-carbon molecular bonds.

To promote hydrocracking reactions, and not just hydroprocessing reactions, the hydroprocessing reactor(s) preferably operate at a temperature in the range of from about 399°C (750°F) to about 460°C (860°F), more preferably in the range from about 416°C (780°F) to about 443°C (830°F), preferably operating at a pressure in the range from about 6.9 MPa (1000 psig) to about 20 .7 MPa (3000 psig), more preferably in the range of about 10.3 MPa (1500 psig) to about 17.2 MPa (2500 psig) . pressure) and preferably operates(s) at a space velocity (e.g. liquid hourly space velocity (LHSV) defined as the ratio of feed volume to reactor volume per hour) in the range of about 0.05 to about 0.45 h ^-1 , more preferably in the range from about 0.1 to about 0.35 h - ¹ .

The difference between hydrocracking and hydrotreatment can also be expressed in units of bottoms conversion (where hydrocracking leads to a significant conversion of high-boiling hydrocarbons to low-boiling hydrocarbons, while this is not the case with hydrotreating). The hydroprocessing systems described herein can result in bottoms conversions of from about 40% to about 95%, preferably from about 55% to about 90%.

The preferred conversion range usually depends on the type of feedstock due to differences in processing difficulty of different feedstocks. In some cases, the conversion may remain at the same level or may be at least about 5% higher, preferably at least about 10% higher compared to the operation of the fluidized bed reactor before upgrading to use a two-way catalyst system, as described herein. document.

III. Improvement of hydroprocessing fluidized bed reactor

In FIG. 3A, 3B, 3C, and 3D are flow charts illustrating exemplary methods for upgrading a fluidized bed reactor to recycle vacuum residues without building up recycled asphaltenes in a hydroprocessing system, such as vacuum residues.

In FIG. 3A is a flow diagram illustrating an exemplary process for improving a vacuum residue recycle fluidized bed reactor without buildup of recycled asphaltenes, comprising: (1) operating a fluidized bed reactor using a heterogeneous heavy oil hydroprocessing catalyst under initial conditions, optionally with vacuum recycle residues and buildup of recycled asphaltenes; (2) adding or forming in situ particulate metal sulfide catalyst particles in a fluidized bed reactor to obtain an improved fluidized bed reactor with a two-way catalyst system consisting of a heterogeneous catalyst and particulate metal sulfide catalyst particles; (3) operation of an improved fluidized bed reactor using a two-way catalyst system for hydroprocessing heavy oil to produce hydrocarbon products; (4) subjecting the hydrocarbon products to vacuum distillation and separating distillates from vacuum residues containing particles of residual metal sulfide catalyst; and (5) recycling at least a portion of the vacuum residues containing residual metal sulfide catalyst particles to the improved fluidized bed reactor without buildup of recycled asphaltenes in the fluidized bed hydroprocessing system (eg, vacuum residues).

In accordance with some embodiments of the invention, the heterogeneous catalyst used in the initial operation of the fluidized bed reactor at the initial conditions is a commercially available catalyst commonly used in fluidized bed reactors. To achieve maximum efficiency, the initial operating conditions of the reactor are preferably at a level at which the formation of deposits and fouling of equipment is kept within acceptable limits. Attempts have been made to increase the absolute conversion of heavy oil and asphaltenes, as well as to increase the overall production of matched products by recycling the vacuum residues to the fluidized bed reactor. While vacuum residue recycling may theoretically work, it

- 14 041453 often results in a buildup of recycled asphaltenes in the hydroprocessing system, which increases the risk of equipment fouling, often requiring more frequent shutdown and cleaning of the hydroprocessing reactor and associated equipment such as pipes, columns, heaters, heat exchangers, heterogeneous catalysts and/or separation equipment.

In order to provide more efficient recycling of vacuum residues and eliminate or reduce the buildup of recycled asphaltenes in the hydroprocessing system, the fluidized bed reactor will be improved to use a two-way catalyst system containing a heterogeneous catalyst and dispersed metal sulfide catalyst particles. Operation of the improved fluidized bed reactor using a two-way catalyst system allows vacuum residues to be recycled without buildup of recycled asphaltenes or even without reduction of asphaltenes in the vacuum residues even at one or more of higher conversion, higher temperature, and/or higher production rates compared to the original conditions. This results in less equipment fouling and less frequent shutdowns and cleanups than when recirculating vacuum residues with buildup of recycled asphaltenes.

The dispersed metal sulfide catalyst particles can be prepared separately and then added to the fluidized bed reactor, which together with the heterogeneous catalyst forms a two-component catalyst system.

Alternatively or additionally, at least a portion of the dispersed metal sulfide catalyst particles may be produced in situ within a fluidized bed reactor. Additional information about particulate metal sulfide catalyst particles and how they are formed is provided below.

In FIG. 3B is a flow diagram illustrating another exemplary process for upgrading a fluidized bed reactor to recycle vacuum residues at higher conversion without buildup of recycled asphaltenes, comprising: (1) operating the fluidized bed reactor using a heterogeneous heavy oil hydroprocessing catalyst at baseline conditions. , optionally with recirculation of vacuum residues and buildup of recirculating asphaltenes; (2) adding or forming in situ particulate metal sulfide catalyst particles in a fluidized bed reactor to obtain an improved fluidized bed reactor with a two-way catalyst system consisting of a heterogeneous catalyst and particulate metal sulfide catalyst particles; (3) operating the improved fluidized bed reactor using a two-way catalyst system for hydroprocessing heavy oil to produce hydrocarbon products at a higher conversion than baseline; (4) subjecting the hydrocarbon products to vacuum distillation and separating distillates from vacuum residues containing particles of residual metal sulfide catalyst; and (5) recycling at least a portion of the vacuum residues containing residual metal sulfide catalyst particles to the improved fluidized bed reactor without buildup of recycled asphaltenes in the fluidized bed hydroprocessing system (eg, vacuum residues).

In FIG. 3C is a flowchart illustrating another exemplary process for upgrading a fluidized bed reactor to recycle vacuum residues at a similar conversion and reduced amounts of asphaltenes, comprising: (1) operating a fluidized bed reactor using a heterogeneous heavy oil hydroprocessing catalyst at source conditions , optionally with recirculation of vacuum residues and buildup of recirculating asphaltenes; (2) adding or forming in situ particulate metal sulfide catalyst particles in a fluidized bed reactor to obtain an improved fluidized bed reactor with a two-way catalyst system consisting of a heterogeneous catalyst and particulate metal sulfide catalyst particles; (3) operation of an improved fluidized bed reactor using a two-way catalyst system for hydroprocessing heavy oil to produce hydrocarbon products at a similar conversion compared to baseline; (4) subjecting the hydrocarbon products to vacuum distillation and separating distillates from vacuum residues containing particles of residual metal sulfide catalyst; and (5) recycling at least a portion of the vacuum residues containing particles of residual metal sulfide catalyst to the improved fluidized bed reactor with reduced asphaltenes in the fluidized bed hydroprocessing system (eg, vacuum residues).

In FIG. 3D is a flowchart illustrating another exemplary process for improving a fluidized bed reactor to recycle vacuum residues at higher conversion and reduced amounts of asphaltenes, comprising: (1) operating a fluidized bed reactor using a heterogeneous catalyst for hydroprocessing heavy oil in raw conditions, optionally with recirculation of vacuum residues and buildup of recirculating asphaltenes; (2) adding or in situ formation of dispersed metal sulfide catalyst particles in a fluidized bed reactor to obtain an improved reactor

- 15 041453 fluidized bed with a two-component catalytic system consisting of a heterogeneous catalyst and particles of a dispersed metal sulfide catalyst; (3) operating the improved fluidized bed reactor using a two-way catalyst system for hydroprocessing heavy oil to produce hydrocarbon products at a higher conversion than baseline; (4) subjecting the hydrocarbon products to vacuum distillation and separating distillates from vacuum residues containing particles of residual metal sulfide catalyst; and (5) recycling at least a portion of the vacuum residues containing particles of residual metal sulfide catalyst to the improved fluidized bed reactor with reduced asphaltenes in the fluidized bed hydroprocessing system (eg, vacuum residues).

In some embodiments of the invention, the rate of production of conversion products can be increased by operating an improved fluidized bed reactor using a two-way catalyst system and recirculating vacuum residues by at least one of the following: (i) higher temperature and higher conversion at the same or similar performance, as when working in the original conditions; (ii) higher temperature and higher productivity at the same or similar conversion as when operating under the original conditions; or (iii) higher temperature, higher throughput and higher conversion than when operating under baseline conditions.

In some embodiments, the vacuum residues may be recycled at a recycle rate of from about 1% to about 50%, preferably from about 5% to about 40%, and more preferably from about 10% to about 30%. The recirculation ratio can be expressed as a percentage, determined by the ratio of the recycled amount of vacuum residues to the amount of fresh raw materials, either in volume or mass terms. These percentages indicate the vacuum residue flow rate as a volume percentage of the fresh feed flow rate. The recirculation ratio can also be easily converted to a mass fraction in percent if the densities of the feedstock and vacuum residues are known.

In some embodiments of the invention, productivity can be increased by at least 2.5%, at least 5%, at least 10%, or at least 20% compared to baseline.

In some embodiments of the invention, the conversion can be increased by at least 2.5%, at least 5%, at least 7.5%, at least 10%, or at least 15% compared to initial conditions.

In some embodiments of the invention, the temperature can be increased by at least 2.5°C, at least 5°C, at least 7.5°C, or at least 10°C compared to the initial conditions.

In some embodiments of the invention, after upgrading the fluidized bed reactor to use a two-way catalyst system and recycle vacuum residues, the equipment fouling rate can be reduced by at least 5%, 25%, 50%, or 75% compared to the equipment fouling rate when operating at baseline and/or when recirculating vacuum residues without upgrading to use a two-way catalyst system. In some embodiments of the invention, after upgrading to use a two-way catalyst system, the absolute conversion of asphaltenes in the hydroprocessing system may be lower, the same, or even higher than when the fluidized bed reactor was operated under the initial conditions.

In some embodiments of the invention, the concentration of asphaltenes in the improved fluidized bed reactor can be reduced by at least about 5%, preferably at least about 10%, more preferably at least about 20% compared to the asphaltene concentration in the original conditions with recirculation vacuum residues.

In some embodiments, the particulate metal sulfide catalyst particles may be formed in situ within the bulk of the heavy oil feedstock that is added to the fluidized bed reactor. This can be achieved by first mixing the catalyst precursor with the bulk of the heavy oil feedstock to form a conditioned feedstock and then heating the conditioned feedstock to decompose the catalyst precursor and initiate or cause the catalyst metal to react with the sulfur and/or sulfur-containing molecules in the heavy oil and/or added to heavy oil to form dispersed metal sulfide catalyst particles.

The catalyst precursor may be oil soluble and have a decomposition temperature in the range of about 100°C (212°F) to about 350°C (662°F), or in the range of about 150°C (302°F) to about 300°C (572°F), or in the range from about 175°C (347°F) to about 250°C (482°F). Exemplary catalyst precursors include organometallic complexes or compounds, in particular oil-soluble compounds or complexes of transition metals and organic acids having a temperature or decomposition range sufficient to avoid significant

- 16 041453 good decomposition when mixed with heavy oil feedstock under suitable mixing conditions. When mixing the catalyst precursor with a hydrocarbon oil diluent, the advantage is to maintain the diluent at a temperature below which significant degradation of the catalyst precursor occurs. One skilled in the art, in accordance with the present disclosure, can select a mixing temperature profile that results in direct mixing of the selected precursor composition without significant degradation to particulate metal sulfide catalyst formation.

Exemplary catalyst precursors include, but are not limited to, molybdenum-2-ethylhexanoate, molybdenum octanoate, molybdenum naphthenate, vanadium naphthenate, vanadium octanoate, molybdenum hexacarbonyl, vanadium hexacarbonyl, and iron pentacarbonyl. Other catalyst precursors include molybdenum salts containing a plurality of cationic molybdenum atoms and a plurality of carboxylate anions of at least 8 carbon atoms and which is at least one of: (a) aromatic, (b) alicyclic, or (c) branched, unsaturated and aliphatic chains. By way of example, each carboxylate anion may have 8 to 17 carbon atoms, or 11 to 15 carbon atoms. Examples of carboxylate anions that fit at least one of the above categories include carboxylate anions derived from carboxylic acids selected from the group consisting of 3-cyclopentylpropionic acid, cyclohexane-butanoic acid, biphenyl-2-carboxylic acid, 4-heptylbenzoic acid, 5-phenylvaleric acid, geranic acid (3,7-dimethyl-2,6octadienoic acid) and combinations thereof.

In other embodiments, carboxylate anions suitable for use in the preparation of oil-soluble, thermally stable molybdenum catalyst precursor compounds are derived from carboxylic acids selected from the group consisting of 3-cyclopentylpropionic acid, cyclohexane-butanoic acid, biphenyl-2-carboxylic acid, 4-heptylbenzoic acid, 5 -phenylvaleric acid, geranic acid (3,7-dimethyl-2,6octadienoic acid), 10-undecylenic acid, dodecanoic acid, and combinations thereof. Molybdenum catalyst precursors made with carboxylate anions derived from the above carboxylic acids have been found to have improved thermal stability.

Higher thermal stability catalyst precursors may have a first decomposition temperature of greater than 210°C, greater than about 225°C, greater than about 230°C, greater than about 240°C, greater than about 275°C, or greater than about 290°C. C. Such catalyst precursors may have a maximum decomposition temperature of greater than 250°C, or greater than about 260°C, or greater than about 270°C, or greater than about 280°C, or greater than about 290°C, or greater than about 330 °C.

One skilled in the art, in accordance with the present disclosure, can select a mixing temperature profile that results in direct mixing of the selected precursor composition without significant degradation to particulate metal sulfide catalyst formation.

Since it is within the scope of this invention to directly mix the catalyst precursor with the heavy oil feedstock, in such cases care must be taken to mix the components for a time sufficient to thoroughly mix the catalyst precursor with the feedstock before significant decomposition of the precursor composition occurs. For example, US Pat. No. 5,578,197 (Cyr et al.), the disclosure of which is incorporated herein by reference, describes a process in which molybdenum-2-ethylhexanoate is mixed with bottoms of vacuum tower bitumen for 24 hours before the mixture is heated in a reactor to form a catalyst compound and hydrocrack (see column 10, lines 4-43). While 24 hour mixing under laboratory experimental conditions may be entirely acceptable, such long mixing times make some industrial operations prohibitively expensive. In order to ensure thorough mixing of the catalyst precursor in the heavy oil prior to heating to form the active catalyst, a series of mixing steps are performed using a variety of mixing apparatus prior to heating the conditioned feedstock. These may include one or more low shear inline mixers followed by one or more high shear mixers followed by a surge tank and system around the pump, followed by one or more high pressure multistage pumps used to pressurize the feed stream prior to its introduction into the reactor. hydroprocessing.

In some embodiments, the conditioned feedstock is preheated with a heater prior to entering the hydroprocessing reactor to form at least a portion of the dispersed metal sulfide catalyst particles in situ within the heavy oil prior to entering the reactor. In other embodiments, the conditioned feedstock is heated or further heated in a hydroprocessing reactor to form at least a portion of the dispersed metal sulfide catalyst particles in situ within the heavy oil while it is in the reactor.

- 17 041453

In some embodiments, the particulate metal sulfide catalyst particles may be formed in a multi-step process. For example, an oil soluble catalyst precursor composition may be premixed with a hydrocarbon diluent to form a diluted precursor mixture. Examples of suitable hydrocarbon diluents include, but are not limited to, vacuum gas oil (which has a nominal boiling range of 360-524°C (680-975°F)), decanted oil, or cycled oil (which has a nominal boiling range of 360-550°C ( 680-1022°F)) and gas oil (whose nominal boiling range is 200-360°C (392-680°F)), some heavy oil feedstocks, and other hydrocarbons that nominally boil at a temperature higher than about 200°C.

The ratio of catalyst precursor to hydrocarbon oil diluent used to prepare the diluted precursor mixture may be in the range of about 1:500 to about 1:1, or in the range of about 1:150 to about 1:2, or in the range of about 1 :100 to about 1:5 (eg 1:100, 1:50, 1:30 or 1:10).

The amount of catalyst metal (e.g., molybdenum) in the dilute precursor mixture is preferably in the range of about 100 to about 7000 ppm by weight of the dilute precursor mixture, more preferably in the range of about 300 to about 4000 ppm by weight of the dilute precursor mixture.

The catalyst precursor is preferably mixed with the hydrocarbon diluent at a temperature below the temperature at which a significant portion of the catalyst precursor composition decomposes. Mixing can be carried out at a temperature in the range from about 25°C (77°F) to about 250°C (482°F), or in the range from about 50°C (122°F) to about 200°C (392°F ), or in the range from about 75°C (167°F) to about 150°C (302°F) to obtain a dilute precursor mixture. The temperature at which the dilute precursor mixture is formed may depend on the decomposition temperature and/or other characteristics of the catalyst precursor used and/or characteristics of the hydrocarbon diluent, such as viscosity.

The catalyst precursor is preferably mixed with the hydrocarbon oil diluent for a period of time in the range of about 0.1 seconds to about 5 minutes, or in the range of about 0.5 seconds to about 3 minutes, or in the range of about 1 second to about 1 minute. . The actual mixing time depends, at least in part, on the temperature (ie, the temperature that affects the viscosity of the fluids) and the intensity of the mixing. The intensity of mixing depends, at least in part, on the number of stages, for example, for a static mixer in the system.

Premixing the catalyst precursor with the hydrocarbon diluent to form a dilute precursor mixture, which is then blended with the heavy oil feedstock, greatly facilitates thorough and uniform mixing of the catalyst precursor with the feedstock, particularly in the relatively short period of time required for large scale industrial operations. Forming a dilute precursor mixture reduces overall mixing time while (1) reducing or eliminating differences in solubility between the more polar catalyst precursor and the more hydrophobic heavy oil feed, (2) reducing or eliminating differences in rheology between the catalyst precursor and the heavy oil feed, and/ or (3) breaking down the catalyst precursor molecules to form a solute in the hydrocarbon diluent that is more readily dispersed in the heavy oil feed.

The dilute precursor mixture is then combined with the heavy oil feedstock and mixed for sufficient time and in such a way as to disperse the catalyst precursor throughout the heavy oil to form a conditioned feedstock in which the catalyst precursor is intimately mixed with the heavy oil before thermally decomposing and forming active particles. metal sulfide catalyst. To obtain sufficient mixing of the catalyst precursor in the heavy oil feed, the dilute mixture of the precursor and the heavy oil feed is preferably mixed for a period of time in the range of from about 0.1 seconds to about 5 minutes, or in the range from about 0.5 seconds to about 3 min, or in the range of about 1 s to about 1 min. Increasing the intensity and/or shear energy of the mixing process generally shortens the time required to achieve thorough mixing.

Examples of a mixing device that can be used to effect intimate mixing of the catalyst precursor and/or dilute heavy oil precursor mixture include, but are not limited to, high shear mixing, such as mixing created in a propeller or turbine agitator vessel; a plurality of static mixers in the system; a plurality of static mixers in the system in combination with high shear mixers in the system; a plurality of static mixers in the system in combination with high shear mixers in the system, followed by a surge tank; combinations of the above followed by one or more multistage centrifugal pumps and one or more multistage centrifugal pumps. In accordance with some embodiments of the invention, continuous rather than batch mixing can be accomplished using high capacity pumps having multiple chambers in which the catalyst precursor composition and the heavy oil feed are mixed and mixed as part of the pumping process itself. The above mixing device can also be used for the pre-mixing discussed above, in which the catalyst precursor is mixed with a hydrocarbon diluent to form a catalyst precursor mixture.

In the case of a heavy oil feedstock that is hard or extremely viscous at room temperature, such feedstock may advantageously be heated to soften it and create a feedstock having a sufficiently low viscosity to ensure good mixing of the oil-soluble catalyst precursor with the feedstock composition. . In general, reducing the viscosity of the heavy oil feedstock will reduce the time required to effect thorough and direct mixing of the oil soluble catalyst precursor composition with the feedstock.

The heavy oil feed and the catalyst precursor and/or diluted precursor mixture are advantageously mixed at a temperature in the range of about 25°C (77°F) to about 350°C (662°F), or in the range of about 50°C (122 °F) to about 300°C (572°F), or in the range from about 75°C (167°F) to about 250°C (482°F) to obtain a conditioned feed.

In the case where the catalyst precursor is mixed directly with the heavy oil feed without initially forming a dilute mixture of precursors, it may be advantageous to mix the catalyst precursor and the heavy oil feed for a period of time ranging from about 0.2 seconds to about 10 minutes, or in in the range of about 1 second to about 6 minutes, or in the range of about 2 seconds to about 2 minutes. In addition, it may be useful to mix the catalyst precursor and heavy oil feed at a temperature below the temperature at which a significant portion of the catalyst precursor composition decomposes.

In the case where the catalyst precursor is premixed with the hydrocarbon diluent to form a dilute precursor mixture which is then mixed with the heavy oil feedstock, it is acceptable for the heavy oil feedstock to have a decomposition temperature of the catalyst precursor or to exceed it. In some cases, the hydrocarbon diluent shields individual catalyst precursor molecules and prevents them from agglomerating to form larger particles, temporarily insulates the catalyst precursor molecules from heavy oil heat during blending, and allows the catalyst precursor molecules to disperse sufficiently rapidly throughout the heavy oil feed before decomposition. to release the metal. In addition, to release hydrogen sulfide from sulfur-bearing molecules in heavy oil, additional heating of the feedstock may be required to form metal sulfide catalyst particles. Thus, gradual dilution of the catalyst precursor provides a high level of dispersion in the heavy oil feedstock, resulting in highly dispersed metal sulfide catalyst particles, even if the feedstock is at a temperature above the decomposition temperature of the catalyst precursor.

After the catalyst precursor is well mixed in the heavy oil to form a conditioned feedstock, the composition is heated causing the catalyst precursor to decompose, which releases the catalyst metal from it, causing or allowing the catalyst metal to react with sulfur within and/or when added to the heavy oil and forming active metal sulfide catalyst particles. The metal from the catalyst precursor may first form a metal oxide, which then reacts with the sulfur in the heavy oil to form the metal sulfide compound forming the final active catalyst. Where the heavy oil feed contains sufficient or excess sulfur, the final active catalyst can be formed in situ by heating the heavy oil feed to a temperature sufficient to release the sulfur therefrom. In some cases, sulfur may be released at the same temperature at which the precursor composition decomposes. In other cases, additional heating to a higher temperature may be required.

When the catalyst precursor is intimately mixed with the heavy oil feed, at least a significant portion of the released metal ions are largely sheltered or shielded from other metal ions so that they can form a molecularly dispersed catalyst when reacted with sulfur to form a metal sulfide compound. . In other circumstances, slight agglomeration may occur, resulting in colloidal sized catalyst particles. However, it is believed that the intimate mixing of the catalyst precursor with the feed prior to thermal decomposition of the catalyst precursor produces single catalytic molecules rather than colloidal particles. Simple mixing, in the absence of sufficient mixing of the catalyst precursor with the feed, generally results in the formation of large agglomerated metal sulfide compounds that are micron in size or larger.

In order to form particulate metal sulfide catalyst particles, the conditioned feedstock is heated to a temperature in the range of about 275°C (527°F) to about 450°C (842°F), or in the range of about 310°C (590°F) up to about 430°C (806°F), or in the range from about 330°C

- 19 041453 (626°F) to about 410°C (770°F).

The initial heavy oil catalyst metal concentration provided by the dispersed metal sulfide catalyst particles may be in the range of about 1 to about 500 ppm by weight of the heavy oil feed, or in the range of about 5 to about 300 ppm, or in the range about 10 to about 100 ppm The catalyst can become more concentrated when the volatile fractions are removed from the residual fraction. Vacuum residue recirculation can be a source of particulate metal sulfide catalyst particles that can maintain the desired concentration in the fluidized bed reactor using less catalyst precursor, or it can increase the concentration of particulate metal sulfide catalyst particles, which can help hydroprocess additional asphaltenes provided by recycled vacuum residues.

In the case where the heavy oil feed contains a significant amount of asphaltene molecules, the dispersed metal sulfide catalyst particles may preferentially associate with or remain in close proximity to the asphaltene molecules. The asphaltene molecules may have a greater affinity for the metal sulfide catalyst particles because the asphaltene molecules are preferably more hydrophilic and less hydrophobic than other hydrocarbons found in heavy oil. Because the metal sulfide catalyst particles tend to be very hydrophilic, individual particles or molecules will tend to migrate to more hydrophilic residues or molecules in the heavy oil feed.

Although the highly polar nature of the metal sulfide catalyst particles causes or ensures their association with asphaltene molecules, there is a general incompatibility between highly polar catalyst compounds and hydrophobic heavy oil that requires the aforementioned direct or intimate mixing of the catalyst precursor composition with the heavy oil before decomposition and formation of active catalyst particles. Because the metal catalytic compounds are highly polar, they cannot be effectively dispersed in heavy oil when added directly to it. In practical terms, the formation of smaller catalyst particles results in more catalyst particles, which provide more evenly distributed catalyst sites throughout the heavy oil.

IV. Advanced fluidized bed reactor

In FIG. 4 schematically illustrates an exemplary improved fluidized bed hydroprocessing system 400 that can be used in the disclosed methods and systems. The fluidized bed hydroprocessing system 400 comprises an improved fluidized bed reactor 430 and a hot separator 404 (or other separator such as a distillation column). To create an improved fluidized bed reactor 430, catalyst precursor 402 is first premixed with hydrocarbon diluent 404 in one or more mixers 406 to form catalyst precursor mixture 409. The catalyst precursor mixture 409 is added to the feedstock 408 and mixed with the feedstock in one or more mixers 410 to form a conditioned feedstock 411. To further mix and disperse the catalyst precursor in the conditioned feedstock, the conditioned feedstock is fed into a make-up vessel 412 with a circulation loop 414.

The advanced fluidized bed hydroprocessing system includes means for adding recycled vacuum residues 407. The exact point of addition may be selected based on the configuration and/or needs of the particular hydroprocessing system. In some embodiments, recyclable vacuum residues 407 may be added to feed 408 upstream from at least one of one or more mixers 410, downstream from at least one of one or more mixers 410, to make-up tank 412, or to circulation loop 414. In some embodiments, recirculating vacuum residues 407 may be added at a variety of locations.

Conditioned feedstock from surge vessel 412 is pressurized by one or more pumps 416, passed through preheater 418, and fed into fluidized bed reactor 430 along with pressurized hydrogen gas 420 through inlet 436 located at or near the bottom of fluidized bed reactor 430. The heavy oil material 426 in the fluidized bed reactor 430 contains particulate metal sulfide catalyst particles, schematically shown as catalyst particles 424 .

The heavy oil feedstock 408 may contain any desired fossil fuel feedstock and/or fraction thereof, including, but not limited to, one or more of the following: residues of vacuum columns, coal tar, liquefied coal and other residual fractions. In some embodiments, heavy oil feedstock 408 may contain a significant fraction of high-boiling hydrocarbons (i.e., nominally at 343°C (650°F) or higher, in particular, nominally at 524°C (975°F) or higher) and/or asphaltenes. Asphalten presented

- 20 041453 are complex hydrocarbon molecules that have a relatively low ratio of hydrogen to carbon, which is the result of a significant number of fused aromatic and naphthenic rings with paraffinic side chains (see Fig. 1). Interlayers consisting of fused aromatic and naphthenic rings are held together by heteroatoms such as sulfur or nitrogen and/or polymethylene bridges, thioether bonds, and vanadium and nickel complexes. The asphaltene fraction also has a high sulfur and nitrogen content, which gives crude oil or vacuum bottoms residue, and it may also contain higher concentrations of carbon-forming compounds (ie, which form coke precursors and sludge).

The fluidized bed reactor 430 further comprises an expanded catalyst zone 442 containing a heterogeneous catalyst 444. A lower zone 448 not containing a heterogeneous catalyst is located below the expanded zone 442 of the catalyst, and an upper zone 450 not containing a heterogeneous catalyst is located above the expanded zone 442 of the catalyst. The dispersed metal sulfide catalyst particles 424 are dispersed throughout the material 426 in the fluidized bed reactor 430, including the extended catalyst zone 442, heterogeneous catalyst free zones 448, 450, 452, thus being available to promote enrichment reactions within the zones that are catalyst-free zones in a fluidized bed reactor prior to its upgrade to include a two-way catalyst system.

To promote hydrocracking reactions, and not just hydroprocessing reactions, the hydroprocessing reactor(s) preferably operate at a temperature in the range of from about 399°C (750°F) to about 460°C (860°F), more preferably in the range from about 416°C (780°F) to about 443°C (830°F), preferably operating at a pressure in the range from about 6.9 MPa (1000 psig) to about 20 .7 MPa (3000 psig), more preferably in the range of about 10.3 MPa (1500 psig) to about 17.2 MPa (2500 psig) . pressure) and preferably operates(s) at a space velocity (LHSV), in the range from about 0.05 h ^-1 to about 0.45 h' ¹ , more preferably in the range from about 0.1 h ^-1 to about 0 .35 h ^-1 . The difference between hydrocracking and hydrotreating can also be expressed in units of bottoms conversion (where hydrocracking results in a significant conversion of high-boiling hydrocarbons to low-boiling hydrocarbons, while this is not the case with hydrotreating). The hydroprocessing systems described herein can result in bottoms conversions in the range of about 40% to about 95%, preferably in the range of about 55% to about 90%. The preferred conversion range generally depends on the type of feedstock due to differences in processing difficulty for different feedstocks. Typically, the conversion will be at least about 5% higher, preferably at least about 10% higher compared to the operation of the fluidized bed reactor before upgrading to use a two-way catalyst system, as described herein.

The material 426 in the fluidized bed reactor 430 is continuously recirculated from the upper zone 450 not containing the heterogeneous catalyst to the lower zone 448 not containing the heterogeneous catalyst via a recirculation conduit 452 connected to an ebullation pump 454. At the top of the recirculation conduit 452 is a funnel-shaped a recirculation bowl 456 through which material 426 is fed from the upper zone 450 that does not contain heterogeneous catalyst.

Recycled material 426 is mixed with fresh conditioned feed 411 and hydrogen gas 420.

The fresh heterogeneous catalyst 444 is introduced into the fluidized bed reactor 430 through the catalyst inlet tube 458, and the spent heterogeneous catalyst 444 is withdrawn through the catalyst recovery tube 460. While the catalyst recovery tube 460 cannot distinguish between fully spent catalyst, partially spent but active catalyst, and fresh catalyst, the presence of dispersed metal sulfide catalyst particles 424 provides additional catalytic activity within the expanded catalyst zone 442, recycle channel 452, and also lower and upper zones 448, 450 not containing a heterogeneous catalyst. The addition of hydrogen to hydrocarbons in addition to the heterogeneous catalyst 444 minimizes the formation of deposits and coke precursors that are often responsible for deactivating the heterogeneous catalyst.

The fluidized bed reactor 430 further includes an outlet 438 at or near the top through which converted material 440 is withdrawn.

The converted material 440 is introduced into a hot separator or distillation column 4 04. The hot separator or distillation column 404 separates one or more volatile fractions 405, which(s) are(are) recovered from the top of the hot separator 404, from the residual fraction 407, which is recovered from bottom of the hot separator or distillation column 404. Residual cut 407 contains residual metal sulfide catalyst particles, schematically shown as catalyst particles 424. If desired, at least a portion of the residual fraction 407 may be recycled back to the fluidized bed reactor 430 to form a portion of the feed and feed additional metal sulfide catalyst particles. Alternatively, the bottom fraction 407 may be further processed using downstream process equipment such as another fluidized bed reactor. In this case, separator 404 may be an intermediate separator.

In some embodiments of the invention, operating an improved fluidized bed reactor using a two-way catalyst system and with recirculation of vacuum residues may result in the same or less fouling of equipment compared to operating a fluidized bed reactor in the original conditions using only a heterogeneous catalyst, and not a two-way catalyst system. . For example, the fouling rate of equipment when operating an advanced fluidized bed reactor using a two-way catalyst system and with recirculation of vacuum residues can result in frequent heat exchanger shutdowns and/or distillation column shutdowns for purification that are the same or less than when operating the fluidized bed reactor in the original conditions.

As an additional or alternative option, the fouling rate of equipment when operating an advanced fluidized bed reactor using a two-way catalyst system and with recirculation of vacuum residues can lead to frequent changes or cleaning of filters and coarse filters that are the same or less than when operating a fluidized bed reactor. in initial conditions.

As an additional or alternative option, the fouling rate of equipment when operating an advanced fluidized bed reactor using a two-way catalyst system and with recirculation of vacuum residues can lead to frequent switching to standby heat exchangers that are similar or smaller than during the initial operation of the fluidized bed reactor.

As an additional or alternative option, the fouling rate of equipment when operating an advanced fluidized bed reactor using a two-way catalyst system and with recirculation of vacuum residues can lead to lower temperatures of the skin of equipment selected from one or more heat exchangers, separators or distillation columns, compared with the original operation. fluidized bed reactor.

As an additional or alternative option, the fouling rate of equipment when operating an improved fluidized bed reactor using a two-way catalyst system and with recirculation of vacuum residues can lead to lower temperatures of the furnace tube metal, compared with the initial operation of the fluidized bed reactor.

As an additional or alternative option, the fouling rate of equipment when operating an advanced fluidized bed reactor using a two-way catalyst system and with recirculation of vacuum residues can lead to a decrease in the rate of increase in the design fouling resistance factors of heat exchangers, compared with the initial operation of the fluidized bed reactor.

V. Experimental studies and results

A series of experiments was carried out using a two-stage laboratory facility with a fluidized bed of a catalyst. These tests included both no recirculation and recirculation of vacuum residues to the fluidized bed reactor and were conducted at three different levels of dispersed catalyst. In other respects, the tests were identical using the same Russian export blend (Ural brand) vacuum residue feedstock, the same fluidized-bed supported solid catalyst, and the same process operating parameters (pressure, space velocity, etc.). Tests have shown how the buildup of recycled harmful asphaltenes in a fluidized bed process with recycled vacuum residues can be prevented using a two-way catalyst system.

As schematically illustrated in FIG. 5, to compare the use of a heterogeneous catalyst by itself and a two-way catalyst system consisting of a heterogeneous catalyst in combination with particulate metal sulfide catalyst particles (i.e. particulate molybdenum disulfide catalyst particles), a laboratory plant 500 with two reactors 512, 512 connected in series was used. ' fluidized bed.

In particular, laboratory plant 500 includes a mixer 502 for mixing a catalyst precursor (eg, molybdenum 2-ethylhexanoate, 15% molybdenum by weight) with a heavy oil feed (collectively 501) to form a conditioned feed. Proper mixing is achieved by first premixing the catalyst precursor with the hydrocarbon diluent to form a dilute precursor mixture. For the following test studies, hydrotreated heavy vacuum gas oil was used as the hydrocarbon diluent. The dilute precursor mixture was prepared such that 1 part by weight of the mixture could be added to 99 parts by weight of the heavy oil feed to achieve the target loading of the dispersed metal sulfide catalyst in the conditioned feed. As a specific example, for a test study with a target loading of 30 ppm dispersed metal sulfide catalyst in a conditioned feed (with loading expressed as a function of metal concentration), a dilute precursor mixture was prepared with a metal concentration of 3000 ppm.

It should be noted that for comparative test studies that did not use a dispersed metal sulfide catalyst, a hydrocarbon diluent (hydrotreated heavy vacuum gas oil) was added to the heavy oil feedstock at the same ratio of 1 part by mass of heavy vacuum gas oil (HVGO) to 99 parts by mass feedstock from heavy oil. This ensures that the initial composition will be the same between tests using a two-way catalyst system and tests using only a heterogeneous catalyst (fluidized bed), thus providing a direct comparison of test results.

Heavy oil feedstock and operating conditions for actual testing are more specifically defined in the examples below. The heterogeneous catalyst was a commercially available catalyst commonly used in fluidized bed reactors. The conditioned feed was recirculated and returned to the mixing vessel 502 via the pump 504, as is the case with the make-up vessel and circulation loop. A high-precision positive displacement pump 506 was used to withdraw the conditioned feedstock from the recirculation loop and compress it to reactor pressure. Hydrogen gas 508 was fed into the pressurized feedstock and the resulting mixture was passed through a preheater 510 before being introduced into the first fluidized bed reactor 512.

Each of the fluidized bed reactors 512, 512' had an internal volume of about 3000 ml and contained a wire mesh guard 514 to contain the heterogeneous catalyst within the reactor. Each reactor 512, 512' is also equipped with a recirculation line 511, 511' and a recirculation pump 513, 513' which provides the required flow rate in the reactors to expand the heterogeneous catalyst bed. The combined volume of both reactors and their respective recycle lines, all of which were maintained at a certain reactor temperature, was 6700 ml. This is the thermal reaction volume of the system and was used as the basis for calculating the liquid hourly space velocity (LHSV).

In FIG. 5, the predetermined catalyst height in each fluidized bed reactor 512, 512' is schematically indicated by the lower broken line 516, and the expanded catalyst bed during use is schematically indicated by the upper broken line 518. reactor 512' for further hydroprocessing.

Additional enrichment material 520' from the second reactor 512' was introduced into a hot separator 522 to separate low-boiling hydrocarbon products and gases 524 from the unconverted liquid fraction (or separator bottoms) 526. The hydrocarbon products gases and vapors 524 were cooled and passed into a cold separator 528 where these were separated into gases 530 and converted hydrocarbon products, which were recovered as separator overhead products 532.

The separator bottoms 526 were batch-processed using a separate (ie stand-alone) batch vacuum distillation unit 534. Dotted lines indicate batch processing, although continuous processing is used within the scope of the present invention. Although vacuum distillation in a commercial plant is performed in a closed on-line distillation column, a batch vacuum distillation unit 534 was used for testing purposes in a laboratory plant. Batch vacuum distillation unit 534 processed 6000 g of separator bottoms 526 with each batch being processed for 6 hours producing separator overhead products 536 and vacuum bottoms product 538. The portions were treated at a pressure of about 1.5 mm Hg, which allowed to reach a final temperature equivalent to atmospheric temperature of 975°F, with a tank temperature of less than 650°F, thus preventing the onset of cracking reactions during vacuum distillation.

The batch vacuum distillation unit 534 processed four batches of vacuum distillation each day, which provided the desired vacuum distillation product for both analysis and recycling. Under recirculation conditions, the vacuum residue product 538 was recycled at 20% by volume of the fresh vacuum residue feed rate by recirculating it to the mixer 502 where it was mixed with the raw material components 501.

Example 1

The process used in Example 1 was a comparative example for which the above-described laboratory plant was used with only a heterogeneous fluidized bed catalyst. For Example 1, no dispersed metal sulfide catalyst was used (meaning no two-way catalyst system) and the process was run without recirculation of vacuum residues to the fluidized bed reactor. The process was run at a liquid hourly space velocity (LHSV) of 0.3 h ⁻¹ and a weighted average bed temperature (WABT) of 414° C. in both reactor stages. LHSV is defined as the volume of vacuum residue fresh feed fed per hour per thermal reaction volume. Under these conditions, a vacuum residue conversion of approximately 55% was achieved, with

- 23 041453 conversion was determined based on cut-off temperature of 538°C (1000°F).

A sample of the laboratory plant separator bottom product was subjected to laboratory distillation using ASTM D-1160 to obtain a 538°C+ vacuum residue product fraction separation, which was analyzed for C7 asphaltene content. The content of C7-asphalten was determined as the difference between the content of heptane-insoluble impurities and toluene-insoluble impurities in the sample.

The result of Example 1 was plotted on the result graph shown in FIG. 6 and represented as an open square.

Example 2

The process used in Example 2 was carried out in the same manner as in Example 1, except that an offline batch vacuum distillation unit was used to produce a vacuum bottom product, which was then recycled to the fluidized bed reactor as part of the heavy oil feed process. . Batch vacuum distillation was carried out at a boiling point of 524°C (975°F), while the resulting vacuum bottoms product was added to the fluidized bed heavy oil feed process at 20% v/v vacuum residue fresh feed. LHSV was maintained at 0.3 h ^-1 noting that the determination of LHSV was based on the supply of fresh vacuum residue as described in example 1.

Data for example 2 was collected at two different reactor temperatures (411 and 414° C.), resulting in a residue conversion of 53 and 58%, respectively. As described in Example 1, a sample of the 538° C.+ vacuum residue product was obtained by D-1160 laboratory vacuum distillation and then analyzed for C7-asphalten content. The results are shown in the results graph illustrated in FIG. 6 and are shown as filled squares connected by a line.

As seen in FIG. 6, at the same residue conversion, the process used in Example 2, with vacuum residue recycling, resulted in significantly higher C7 asphaltenes compared to the process of Example 1, indicating a significant increase in recycled harmful asphaltenes when recycling was used.

Example 3

The process used in example 3 was carried out in the same manner as in example 2, except that the dispersed metal sulfide catalyst was added to the original mixture of heavy oil. As noted above, the catalyst precursor was pre-dispersed in a hydrocarbon diluent (heavy vacuum gas oil), and then the premixed mixture of catalyst precursor and hydrocarbon diluent (dilute catalyst precursor) was added to the vacuum residue of the feed oil. The catalyst precursor/hydrocarbon diluent was prepared such that an impurity ratio of 1 wt. % fresh feed mixture provided a dispersed catalyst concentration of 20 ppm by weight (as molybdenum).

The process was run at a liquid hourly space velocity (LHSV) of 0.3 h ⁻¹ and a weighted average bed temperature (WABT) of 414° C. in both reactor stages. This resulted in a residue conversion of 52%. As noted above, a sample of the 538°C+ vacuum residue product was obtained by D-1160 laboratory vacuum distillation, and then analyzed for C ₇ -asphalten content.

The test result is shown in the graph of Fig. 6 in the form of an open triangle. Compared to the result of example 1 (open square), the asphaltene content is reduced due to the action of the dispersed metal sulfide catalyst. As additional data from Example 4 shows, the reduced asphaltene content was not simply the result of reduced conversion.

Example 4

The process used in example 4 was carried out in the same manner as in example 2, with recirculation of vacuum residues, except that the dispersed metal sulfide catalyst was added to the initial mixture using the method from example 3. The concentration of fresh dispersed catalyst was 20 h / ppm by weight (as molybdenum) based on the amount of fresh feed mixture (mixture of vacuum residue and dispersed catalyst/hydrocarbon diluent). The recycled vacuum residue stream also contained residual (used) dispersed metal sulfide catalyst that was added to the heavy oil feedstock in addition to the fresh dispersed catalyst.

Data for example 4 was collected at two different fluidized bed reactor temperatures (414 and 418° C.), resulting in a residue conversion of 52 and 58%, respectively. As noted above, separation of the 538°C+ vacuum residue product fraction was obtained by laboratory distillation and measurements of the C7-asphalten content were made. The results are shown in the graph in Fig. 6 as solid triangles connected by a line that show a statistically linear relationship between asphaltene concentration and conversion, but with all points significantly lower than the results from Example 2.

In contrast to the results from examples 1 and 2, which were obtained without using a two-component catalyst system containing a heterogeneous catalyst and dispersed me

- 24 041453 talsulfide catalyst, the results from example 4 with 20 ppm dispersed metal sulfide catalyst and recirculation of vacuum residues overlap the result from example 3 without recirculation. This means that the use of the 20 ppm dispersed catalyst prevented buildup of recycled asphaltenes. When used in combination with vacuum residue recycle, the dispersed catalyst provides a twofold advantage: (1) the initial asphaltene content (without recycle) is (or can be) reduced; and (2) the build-up of recycled asphaltenes is prevented when vacuum residues are recycled back to the fluidized bed reactor.

Example 5

The process used in Example 5 was carried out in the same manner as in Example 3, except that the concentration of the dispersed metal sulfide catalyst was increased to 35 ppm by weight (as molybdenum). The process was carried out at an average fluidized bed temperature of 415° C. in both reactor stages, resulting in a residue conversion of 54%.

The obtained content of C7 asphaltenes of the separation of the fraction obtained under laboratory conditions of the product of the vacuum residue is shown in the graph in FIG. 6 in the form of an unshaded rhombus. The result from Example 5 at 35 ppm dispersed metal sulfide catalyst showed a further reduction in asphaltene content and at a higher conversion compared to the result in Example 3 at 20 ppm.

Example 6

The process used in Example 6 was carried out in the same manner as in Example 4, except that the concentration of the dispersed metal sulfide catalyst increased to 35 ppm by weight (as molybdenum). The process was carried out at average fluidized bed temperatures of 415, 418, 420, and 425° C., resulting in residue conversions of 55, 59, 62, and 66%, respectively.

The obtained contents of C7-asphaltenes of the respective compartments of the fraction of the laboratory-produced product of the vacuum residue are shown in the graph in FIG. 6 in the form of a filled diamond, connected by a line of best fit. Similar to the results from Examples 3 and 4, the results of Example 6 overlapped those of Example 5, showing that the dispersed metal sulfide catalyst prevented buildup of recycled asphaltenes in addition to reducing background asphaltenes without recycling vacuum residues.

Example 7

With reference to the graph in Fig. 7 and in the example of the process illustrated in FIG. 3B, an improved fluidized bed reactor using a two-way vacuum residue recycle catalyst system can operate at a higher conversion without buildup of recycled asphaltenes, as indicated by the solid horizontal arrow extending to the right of the open square. This is in contrast to the dashed vertical arrow above the open square, where recirculation of vacuum residues increased the asphaltene concentration at the same conversion.

The addition of a dispersed metal sulfide catalyst to create a two-way catalyst system can increase the conversion of the residue while maintaining the same concentration of asphaltene, which leads to the following: (1) the rate of production of conversion products is increased, while (2) the risk of fouling of the process plant or equipment is prevented or reduced, and (3 ) the quality of the bottom product is maintained.

This embodiment of the invention is preferred when the initial fouling of the process unit is controlled and the economic benefit is most favorable for increasing the rate of production of conversion products.

Example 8

With reference to the graph in Fig. 8 and in the example of the process illustrated in FIG. 3C, an improved fluidized bed reactor using a two-way vacuum residue recycle catalyst system can operate at the same conversion and with a significant reduction in asphaltene concentration, as indicated by the solid vertical arrow below the open square. This is in contrast to the dashed vertical arrow above the open square, where recirculation of vacuum residues increased the asphaltene concentration at the same conversion.

The addition of a dispersed metal sulfide catalyst to form a two-way catalyst system allows the residue conversion to be maintained while the asphaltene concentration is reduced, resulting in: (1) maintaining the same rate of production of conversion products, while (2) reducing fouling of the process plant or equipment, and (3) improving quality cubic product.

This embodiment of the invention is preferred when the initial fouling of the process unit and/or the quality of the bottom product is limited so that the economic benefit is maximized by reducing fouling and/or improving the quality of the bottom product.

- 25 041453

Example 9

With reference to the graph in Fig. 9 and in the example of the process illustrated in FIG. 3D, an improved fluidized bed reactor using a two-way catalytic system with vacuum residue recycle can operate at higher conversion and lower asphaltene concentrations, as indicated by the solid vertical arrow running diagonally to the right and below the open square. This is in contrast to the dashed vertical arrow above the open square, where recirculation of vacuum residues increased the asphaltene concentration at the same conversion.

Adding a dispersed metal sulfide catalyst to create a two-component catalyst system allows you to increase the conversion of the residue and at the same time reduce the concentration of asphaltene, which leads to the following: (1) the rate of production of conversion products increases, although to a lesser extent than in example 7, while (2) clogging of the process plant or equipment is reduced and (3) the quality of the bottom product is improved, but to a lesser extent than in example 8.

This embodiment of the invention balances the benefits in such a way as to optimize the overall economics of the process. The illustration in this example shows the case where a production improvement is relatively more valuable than a reduction in process fouling and/or an improvement in bottoms product quality.

Example 10

With reference to the graph in Fig. 10 and in the example of the process illustrated in FIG. 3D, an improved fluidized bed reactor using a two-way vacuum residue recycle catalyst system can operate at higher conversion and lower asphaltene concentrations, as indicated by the solid vertical arrow running diagonally to the right and below the open square. This is in contrast to the dashed vertical arrow above the open square, where recirculation of vacuum residues increased the asphaltene concentration at the same conversion.

Adding a dispersed metal sulfide catalyst to create a two-component catalytic system allows you to increase the conversion of the residue and reduce the concentration of asphaltene, which leads to the following: (1) the rate of production of conversion products increases, although to a lesser extent than in examples 7 and 9, while (2) clogging of the process plant or equipment is reduced and (3) the quality of the bottom product is improved, although to a lesser extent than in example 8, but to a greater extent than in example 9.

Compared to Example 9, this embodiment of the invention illustrates a case where reducing process unit fouling and/or improving bottoms product quality is relatively more cost effective than increasing conversion product production rate.

The present invention may be embodied in other separate forms without departing from its spirit or essential characteristics. The described embodiments of the invention are to be considered in all respects only as an illustration and not as a limitation. Therefore, the scope of the invention is defined by the appended claims and not by the preceding description. All changes that fall within the meaning and equivalence range of the claims are to be embraced by their scope.

Claims (16)

CLAIM 1. A method for improving a fluidized bed hydroprocessing system that contains one or more fluidized bed reactors, comprising the following steps: operating a fluidized bed reactor using a heterogeneous heavy oil hydroprocessing catalyst with initial conditions, the initial conditions including a rate that is related to the operating temperature, productivity, and conversion of said reactor; adding or in situ formation of particulate metal sulfide catalyst particles in a fluidized bed reactor to obtain an improved fluidized bed reactor with a two-way catalyst system consisting of a heterogeneous catalyst and particulate metal sulfide catalyst particles; operating the improved fluidized bed reactor using a two-way catalyst system at the same or higher rate as compared to the corresponding rate of said fluidized bed reactor operating at baseline for hydroprocessing heavy oil to produce hydrocarbon products; subjecting the obtained hydrocarbon products to one or more separation processes, including vacuum distillation and separation of distillates from vacuum residues containing residual metal sulfide catalyst particles; And - 26 041453 recycling at least part of the obtained vacuum residues containing residual metal sulfide catalyst particles to said improved fluidized bed reactor, so that the concentration of asphaltenes in said fluidized bed hydroprocessing system remains at the same or lower level, and the vacuum residues are recycled with a recirculation ratio from 1 to 50%, characterizing the ratio of the flow rate of recycled vacuum residues to the flow rate of fresh heavy oil added to the improved fluidized bed reactor, expressed as a percentage by volume. 2. The process of claim 1, wherein operating the improved fluidized bed reactor comprises operating at a higher conversion than the baseline conversion without causing a buildup of recycled asphaltenes in the vacuum bottoms, the higher conversion being chosen to increase the rate of production. conversion products compared to baseline without increasing equipment fouling and/or without reducing bottoms product quality. 3. The process of claim 1, wherein operating the improved fluidized bed reactor comprises operating at a similar conversion as the baseline conversion and with reduced asphaltene concentration in the vacuum residue, wherein operating the improved fluidized bed reactor at the same conversion maintains the rate of production of the conversion products. compared to the initial conditions with a decrease in equipment clogging and / or with an improvement in the quality of the bottom product. 4. The process of claim 1, wherein operating the improved fluidized bed reactor comprises operating at a higher conversion than the baseline conversion and with a reduction in the concentration of asphaltenes in the vacuum residues, the higher conversion being chosen to increase the rate of production of conversion products. compared to the initial conditions with a decrease in equipment clogging and / or with an improvement in the quality of the bottom product. 5. Process according to any one of claims 1 to 4, wherein the vacuum residues are recycled at a recirculation ratio of 5 to 40% or 10 to 30%, depending on the flow rate of the recycled vacuum residues as a percentage by volume of the fresh heavy oil flow rate, added to the advanced fluidized bed reactor. 6. The method according to any one of claims 1 to 5, wherein the operation of the improved fluidized bed reactor using a two-way catalyst system is carried out at a similar or higher temperature compared to the initial conditions, such as the temperature of the improved fluidized bed reactor increased by at least 2.5°C, at least 5°C, at least 7.5°C, or at least 10°C compared to the operating temperature of the fluidized bed reactor under initial conditions. 7. The method according to any one of claims 1 to 6, wherein the operation of the improved fluidized bed reactor using a two-way catalyst system is carried out at a similar or higher conversion compared to the conversion under the initial conditions, such as when the improved fluidized bed reactor is operated at a conversion, which is increased by at least 2.5%, at least 5%, at least 7.5%, at least 10% or at least 15% compared to the conversion when the fluidized bed reactor is operating occurs under initial conditions. 8. The method according to any one of claims 1 to 7, wherein the operation of the improved fluidized bed reactor using a two-way catalyst system is carried out at a similar or higher productivity compared to the productivity under the initial conditions, such as productivity when the improved fluidized bed reactor is operated at productivity, which is increased by at least 2.5%, at least 5%, at least 10% or at least 20% compared to the conversion when the operation of the fluidized bed reactor occurs under the original conditions. 9. The process according to any one of claims 1 to 8, wherein operating the improved fluidized bed reactor using a two-way catalyst system comprises hydroprocessing heavy oil having a lower quality, such as having a higher concentration of asphaltene compared to baseline heavy oil hydroprocessing, moreover, the concentration of asphaltene in low-quality heavy oil that has been hydroprocessed by an improved fluidized bed reactor is at least 2%, at least 5%, at least 10%, at least 15%, or at least 20% higher than the concentration of asphaltenes in heavy oil that has been hydroprocessed with an advanced fluidized bed reactor while operating at baseline. 10. The method of claim 9, wherein the improved fluidized bed reactor hydroprocesses asphaltenes at an asphaltene conversion that is at least 2% higher, at least 5% higher, at least 10% higher, at least 15% higher or at least 20% higher compared to the conversion of asphaltenes when the operation of the fluidized bed reactor occurs under the original conditions. - 27 041453 11. The method according to any one of claims 1 to 10, wherein the operation of the improved fluidized bed reactor is provided under conditions that the fouling rate of the equipment is not higher than the fouling rate of the equipment during the operation of the fluidized bed reactor under initial conditions, and preferably the operation of the improved fluidized bed reactor bed is provided under conditions that the fouling rate of the equipment is lower than the fouling rate of the equipment during the operation of the fluidized bed reactor in the initial conditions, and the operation of the improved fluidized bed reactor is provided under conditions that reduce the fouling rate of the equipment by at least 5, 25, 50 or 75% compared to the equipment fouling rate during the operation of the fluidized bed reactor under the initial conditions. 12. The method of claim 11, wherein the equipment fouling rate is determined by at least one of the following: (i) frequency of required heat exchanger cleanings; (ii) frequency of switching to standby heat exchangers; (iii) frequency of filter replacement; (iv) frequency of cleaning or replacement of the coarse filter; (v) the rate of decrease in the temperature of the shell of the equipment, including equipment selected from heat exchangers, separators or distillation columns; (vi) the rate of temperature rise of the chimney metal; (vii) rate of increase in design fouling resistance factors for heat exchangers and furnaces; (viii) the rate of increase in pressure drop across the heat exchangers; (ix) frequency of cleaning atmospheric and/or vacuum distillation columns; or (x) frequency of maintenance and scheduled maintenance periods. 13. The method according to any one of claims 1 to 12, wherein the heavy oil includes at least one of heavy crude oil, oil sand bitumen, bottoms from the production of process units, atmospheric column residues having a nominal boiling point of at least 343 °C (650°F), vacuum column residues having a nominal boiling point of at least 524°C (975°F), hot separator residues, resin residues, solvent extraction residues or vacuum residue. 14. The method according to any one of claims 1 to 13, wherein the particulate metal sulfide catalyst particles have a size of less than 1 μm, or a size of less than 500 nm, or a size of less than 250 nm, or a size of less than 100 nm, or a size of less than 50 nm, or a size of less than about 25 nm, or a size less than about 10 nm. 15. The method according to any one of claims 1 to 14, wherein the improvement of the fluidized bed reactor for operation using a two-way catalyst system includes the formation of particles of the dispersed metal sulfide catalyst in situ inside the heavy oil from the catalyst precursor, and, in particular, the formation of particles of the dispersed metal sulfide catalyst in situ inside a heavy oil includes mixing the catalyst precursor with a carbon diluent to form a dilute precursor mixture, mixing the dilute precursor mixture with a heavy oil to form a conditioned heavy oil, and heating the conditioned heavy oil to decompose the catalyst precursor and form particles of the dispersed metal sulfide catalyst in situ inside the heavy oil . 16. A process according to any one of claims 1 to 14, wherein the operation of the fluidized bed reactor using a heterogeneous catalyst for heavy oil hydroprocessing at the initial conditions includes recirculation of vacuum residues and buildup of recycled asphaltenes.