CN111100693A

CN111100693A - Process for hydroprocessing heavy hydrocarbon feedstocks

Info

Publication number: CN111100693A
Application number: CN201811258075.4A
Authority: CN
Inventors: 刘铁斌; 耿新国; 袁胜华; 李洪广; 翁延博; 金建辉
Original assignee: China Petroleum and Chemical Corp; Sinopec Dalian Research Institute of Petroleum and Petrochemicals
Current assignee: China Petroleum and Chemical Corp; Sinopec Dalian Research Institute of Petroleum and Petrochemicals
Priority date: 2018-10-26
Filing date: 2018-10-26
Publication date: 2020-05-05

Abstract

The invention discloses a method for hydrotreating a heavy hydrocarbon raw material. The method comprises the following steps: at least one upflow reactor and at least one downflow fixed bed reactor are connected in series, the heavy hydrocarbon raw material sequentially passes through the upflow reactor and the downflow fixed bed reactor, and the effluent of the downflow fixed bed reactor is separated to obtain each product; the upflow reactor is at least filled with the hydrotreating catalyst, the hydrotreating catalyst carrier at least comprises seven channels penetrating through the carrier, the first channel, the second channel and the third channel penetrate through the sphere center of the catalyst carrier and are mutually communicated, the first channel, the second channel and the third channel are vertical in pairs, the fourth channel, the fifth channel, the sixth channel and the seventh channel are connected and communicated end to end, and the total volume of the channels is 20-60% of the volume of the spherical carrier. The method can improve the overall performance of the catalyst, realize the synchronization of the catalytic performance of the up-flow catalyst and the fixed bed catalyst, improve the catalytic activity and prolong the running period.

Description

Process for hydroprocessing heavy hydrocarbon feedstocks

Technical Field

The invention relates to a method for hydrotreating heavy hydrocarbon raw materials, in particular to a method for hydrotreating heavy oil and residual oil raw materials.

Background

As crude oil gets heavier and worse, more and more heavy oil and residual oil need to be processed. The processing treatment of heavy oil and residual oil not only needs to crack the heavy oil and residual oil into low boiling point products, such as naphtha, middle distillate oil, vacuum gas oil and the like, but also needs to improve the hydrogen-carbon ratio of the heavy oil and residual oil, and the processing treatment needs to be realized by a decarburization or hydrogenation method. Wherein the decarbonization process comprises coking, solvent deasphalting, heavy oil catalytic cracking and the like; the hydrogenation process comprises hydrocracking, hydrofining, hydrotreating and the like. The hydrogenation process can not only hydrogenate and convert residual oil and improve the yield of liquid products, but also remove heteroatoms in the residual oil, has good product quality and has obvious advantages. However, the hydrogenation process is a catalytic processing process, and the problem of deactivation of the hydrogenation catalyst exists, and particularly, the problem of deactivation of the catalyst is more serious when inferior and heavy hydrocarbon raw materials are processed. In order to reduce the cost of processing heavy and poor residual oil and increase the profit of oil refineries, at present, the process for processing heavier and poor residual oil mainly uses a decarburization process, but the product quality is poor and can be utilized only by post-treatment, wherein particularly, deasphalted oil and coker gas oil fractions need to be subjected to hydrotreatment to continue to be processed by using lightening devices such as catalytic cracking or hydrocracking, and therefore, each oil refiner is additionally provided with a hydrotreatment device for deasphalted oil and coker gas oil.

The residue cracking rate of heavy oil and residue hydrotreating technology is low, and the main purpose is to provide raw materials for downstream raw material lightening devices such as catalytic cracking or coking devices. The impurity content of sulfur, nitrogen, metal and the like in the inferior residual oil and the carbon residue value are obviously reduced through hydrotreating, so that the feed which can be accepted by a downstream raw material lightening device is obtained.

In the fixed bed residue hydrotreating technology, the reactor types can be classified into general fixed bed reactors, i.e., downflow mode reactors and upflow reactors, according to the flow pattern of the reactant stream in the reactor. The upflow reactor can reduce the metal content in the feeding, effectively slow down the bed pressure drop, therefore, the upflow reactor is generally arranged before the fixed bed reactor (downflow mode), protect the fixed bed reactor catalyst bed because of the operation later stage metal deposition causes the bed pressure drop to rise rapidly and is forced to shut down. The upflow reactor is characterized in that the oil-gas mixture is fed from the bottom of the reactor to pass through the upflow catalyst bed layer upwards, the liquid phase is continuous in the reactor, the gas phase passes through the reactor in a bubbling mode, the whole catalyst bed layer slightly expands, the deposits of metal, coke and the like can be uniformly deposited on the whole catalyst bed layer, the deposits are prevented from being concentrated on a certain part, the performance of all catalysts is well exerted, and the rapid increase of the pressure drop of the catalyst bed layer is slowed down. Therefore, the catalyst is required to have not only higher hydrogenation activity but also higher crushing strength and wear resistance. Because the catalyst is always in a micro-expansion state in the reactor at high temperature and high pressure, the catalyst has more chances of collision and friction, is easy to break and wear, increases the consumption of the catalyst or brings adverse effects to downstream reactors and equipment. Further, there are also certain requirements for the bulk density, particle shape and particle size distribution of the catalyst, and it is generally considered that a preferable particle shape is a spherical shape with a fine particle size.

The technological process of the prior art is that oil generated at the outlet of an upflow reactor is mixed with fixed bed mixed hydrogen and then sequentially enters a fixed bed demetalization catalyst bed layer, a high-activity desulfurization catalyst bed layer and a carbon residue removal catalyst bed layer. In the combined process of the upflow reactor and the downflow fixed bed reactor, the catalyst of the upflow reactor can only remove part of metals, and the catalyst demetalization performance of the upflow reactor is obviously not matched with the catalyst performance and the operation period of the downflow fixed bed reactor along with the prolonging of the operation time. Considering that the catalyst demetallization capability of the upflow reactor is limited, a certain proportion of demetallization catalyst needs to be filled in the subsequent downflow fixed bed reactor, which is not beneficial to the performance exertion of the whole series of catalysts.

CN1315994C discloses an upflow reaction system, which employs at least two upflow reactors with catalyst layers of different hydrogenation activities to remove not only metals but also sulfur and carbon residue. The upflow reactor is provided with a plurality of different beds filled with catalysts with different hydrogenation activities for removing impurities such as metal, carbon residue, sulfide and the like in the residual oil raw material. The low demetallization capacity of the whole reactor is caused by the filling of catalysts with various performances, and the matching problem with the performances of the subsequent downflow reactor catalysts also exists, which is not favorable for the performance exertion and long-term operation of the catalysts.

Disclosure of Invention

In view of the deficiencies of the prior art, the present invention provides a process for the hydroprocessing of heavy hydrocarbon feedstocks. The method of the invention enables various functional catalysts in the upflow reactor and the downflow fixed bed reactor to be coordinated and matched, thereby improving the overall performance of the catalyst, realizing the synchronization of the catalytic performance of the upflow catalyst and the fixed bed catalyst, not only improving the catalytic activity of the upflow hydrogenation catalyst and the fixed bed desulfurization and denitrification catalyst, but also effectively controlling the demetallization and carbon residue removal effects in the upflow hydrogenation process, reducing the metal toxicity to the fixed bed catalyst, ensuring that the catalyst reduces the inactivation influence of carbon deposition under the condition of higher reaction temperature, and prolonging the operation period.

The invention provides a method for hydrotreating heavy hydrocarbon raw materials, which comprises the following steps: at least one upflow reactor and at least one downflow fixed bed reactor are connected in series, the heavy hydrocarbon raw material sequentially passes through the upflow reactor and the downflow fixed bed reactor, and the effluent of the downflow fixed bed reactor is separated to obtain each product;

wherein the upflow reactor is filled with one of the following hydrotreating catalysts: the hydrotreating catalyst comprises a carrier and an active component, wherein the carrier is spherical, the outer diameter of the spherical carrier is 5.0-10.0 mm, the carrier at least comprises seven channels which penetrate through the carrier, namely a first channel, a second channel, a third channel, a fourth channel, a fifth channel, a sixth channel and a seventh channel, the first channel, the second channel and the third channel penetrate through the sphere center of the catalyst carrier and are communicated with each other, the first channel, the second channel and the third channel are vertical in pairs, the fourth channel, the fifth channel, the sixth channel and the seventh channel are connected and communicated end to end, and the total volume of the channels accounts for 20-60% of the volume of the spherical carrier, preferably 22-60%.

In the hydrotreating catalyst carrier provided by the invention, the fourth channel, the fifth channel, the sixth channel and the seventh channel may be in the same plane or not. Furthermore, the fourth channel, the fifth channel, the sixth channel and the seventh channel are square in the same plane to form a square channel, and further, the square channel and any two of the first channel, the second channel and the third channel are in the same plane and are communicated with the square channel. Further, the length of the fourth, fifth, sixth or seventh channels forming the square channels is at least 1/3 to 2/3 of the outer diameter of the carrier sphere.

In the hydrotreating catalyst carrier provided by the invention, the cross section of the channel is circular, polygonal, elliptical or irregular, preferably circular.

In the hydrotreating catalyst carrier provided by the invention, each channel is a straight channel, and the sectional area of each channel is the same in shape, preferably circular; preferably, the diameters of the first channel, the second channel and the third channel are the same, and the diameters of the fourth channel, the fifth channel, the sixth channel and the seventh channel are the same; and the maximum diameter of the fourth channel, the fifth channel, the sixth channel or the seventh channel is 20-80%, preferably 35-65% of the minimum diameter of the first channel, the second channel or the third channel.

The hydrotreating catalyst of the invention is Al₂O₃-SiO₂As a carrier, wherein SiO₂The weight content is 35-80%, preferably 40-60%.

The hydrotreating catalyst support of the present invention preferably further contains a first metal component oxide, and the first metal component oxide is NiO. The first metal component oxide NiO and Al₂O₃Is 0.03: 1-0.13: 1, preferably 0.05: 1-0.11: 1.

the hydrotreating catalyst carrier of the present invention has the following properties: the specific surface area is 80-200 m²The pore volume is more than 0.79mL/g, preferably 0.79-1.15 mL/g, the pore volume occupied by the pore diameter of 16-100 nm is 35-60% of the total pore volume, and the average pore diameter is more than 18nm, preferably 20-30 nm.

The active metal component of the hydrotreating catalyst comprises a second metal component, namely a VIB group metal element and a third metal component, namely a VIII group metal element, wherein the VIB group metal element is preferably Mo, and the VIII group metal element is preferably Ni and/or Co. Wherein, the content of the second metal component calculated by oxide is 1.0-10.0%, preferably 1.5-9%, the total content of the first metal component and the third metal component calculated by oxide is 1.0-10.0%, preferably 2.0-8.0%, the content of silicon oxide is 35.0-55.0%, and the content of aluminum oxide is 35.0-55.0%.

Furthermore, the catalyst also comprises an auxiliary agent, wherein the auxiliary agent is at least one of P, B, Ti and Zr, and is preferably P.

The preparation method of the hydrotreating catalyst comprises the preparation of a carrier and the loading of an active metal component; the preparation method of the carrier comprises the following steps:

(1) adding an acidic peptizing agent into a silicon source for acidification treatment;

(2) adding aluminum sol and gamma-Al into the step (1)₂O₃Curing agent to prepare paste material;

(3) adding the paste material obtained in the step (2) into a mould, and heating the mould containing the paste material for a certain time to solidify and form the paste material;

(4) and (4) removing the material in the step (3) from the mold, washing, drying and roasting to obtain the catalyst carrier.

In the preparation method of the hydrotreating catalyst of the present invention, the first metal oxide is preferably introduced into the support, and the first metal source (nickel source) may be introduced in step (1) and/or step (2), and the preferred introduction method is as follows: adding a nickel source into the material obtained in the step (1), and dissolving the nickel source into the material. The nickel source can adopt soluble nickel salt, wherein the soluble nickel salt can be one or more of nickel nitrate, nickel sulfate and nickel chloride, and nickel nitrate is preferred.

In the preparation method of the hydrotreating catalyst, the silicon source in the step (1) is one or more of water glass and silica sol, wherein the mass content of silicon in terms of silicon oxide is 20-40%, preferably 25-35%; the acid peptizing agent is one or more of nitric acid, formic acid, acetic acid and citric acid, preferably nitric acid, the mass concentration of the acid peptizing agent is 55-75%, preferably 60-65%, and the adding amount of the acid peptizing agent is that the molar ratio of hydrogen ions to silicon dioxide is 1: 1.0-1: 1.5; the pH value of the silicon source after acidification treatment is 1.0-4.0, preferably 1.5-2.5.

In the preparation method of the hydrotreating catalyst, the aluminum sol in the step (2) can be trihydroxy aluminum chloride and contains Al (OH)₃And AlCl₃The colloidal solution is prepared by boiling and dissolving metal aluminum and HCl which are used as raw materials at a certain temperature, wherein the Al/Cl ratio of the aluminum sol used in the invention is 1.15-1.46, and the content of aluminum oxide is 25-30 wt%; the gamma-Al₂O₃The material is prepared by roasting pseudo-boehmite of a precursor thereof, and has the following properties: the pore volume is more than 0.95mL/g, the preferable pore volume is 0.95-1.2 mL/g, and the specific surface area is 270m²More than g, preferably the specific surface area is 270-330 m²(g) aluminum in the alumina sol of the support prepared, calculated as alumina, with gamma-Al₂O₃The mass ratio of the provided alumina is 1: 1-1: 3; the curing agent is one or more of urea and organic amine salt. The organic amine salt is hexamethylenetetramine. The addition amount of the curing agent is 1: 1.5-1: 2.0 in terms of the molar ratio of nitrogen atoms to silicon dioxide; the solid content of the prepared paste material is 25-45 percent, preferably 28-40 percent by weight of silicon dioxide and aluminum oxide, and the paste material has a plastic body with certain fluidity.

In the preparation method of the hydrotreating catalyst, the die in the step (3) comprises a shell with a spherical cavity and a guide die capable of forming a through passage, the shell is made of rigid material, the external shape can be any shape,preferably spherical or the like. The invention is illustrated by taking the case that the external shape is spherical, and the spherical shell can be composed of two identical hemispheres or four quarter spheres. The diameter of the spherical cavity can be adjusted according to the size of the final catalyst particles. The guide mould capable of forming the through channel is made of a material which can be burnt or dissolved by heating, such as graphite, wood, paper, paraffin, petroleum resin and the like. For example, three columns are made of the material, the length of each column is the diameter of the cavity, the centers of the three columns are intersected and perpendicular to each other, and then four columns are made of the material, the length of each column is 1/3-2/3 of the diameter of the cavity, wherein the fourth column, the fifth column, the sixth column and the seventh column are connected end to end and communicated, and can be in the same plane or different planes。Furthermore, the fourth cylinder, the fifth cylinder, the sixth cylinder and the seventh cylinder are square in the same plane, and further, any two of the square, the first cylinder, the second cylinder and the third cylinder are in the same plane and connected with the square. The total volume of the column is 20-60%, preferably 30-60% of the volume of the spherical carrier.

The structure of the guide die is matched with each through hole in the carrier, namely, a channel generated after the guide die is removed.

And (3) heating the paste material containing mould in the step (3) at the temperature of 70-200 ℃, preferably 100-150 ℃, and keeping the temperature for 30-240 minutes, preferably 50-120 minutes.

In the preparation method of the hydrotreating catalyst, in the step (4), as the pasty material in the mold is heated and releases alkaline gas, the pasty material is solidified and contracted, and then is automatically demolded; washing in the step (4) is to wash the demolded spherical material to be neutral by using deionized water; the drying temperature is 100-150 ℃, and the drying time is 4-10 hours. The roasting temperature is 500-900 ℃, preferably 550-800 ℃, and the roasting time is 2-8 hours.

In the preparation method of the hydrotreating catalyst of the present invention, the loading method of the active metal component may adopt an impregnation method, that is, step (5) is added after the catalyst carrier prepared in step (4), specifically: and (4) impregnating the carrier obtained in the step (4) with active metal components of the supported catalyst, and drying and roasting to obtain the residual oil hydrotreating catalyst.

In the preparation method of the hydrotreating catalyst of the invention, the drying and roasting conditions of the carrier in the step (5) after the carrier is impregnated with the active metal component of the catalyst are as follows: drying at 100-150 ℃ for 4-10 hours, and roasting at 400-600 ℃ for 2-6 hours.

In the heavy hydrocarbon raw material hydrotreating method of the invention, at least one upflow reactor is adopted, one upflow reactor can be arranged, a series process of a plurality of upflow reactors can also be arranged, and one or two upflow reactors are generally arranged. The upflow reactor is preferably filled with the hydrotreating catalyst of the invention, preferably at least two catalyst beds are adopted, and each catalyst bed is filled with the same hydrotreating catalyst of the invention.

In the method for hydrotreating heavy hydrocarbon raw materials, 2-5 catalyst beds are preferably arranged in one upflow reactor, and each catalyst bed preferably adopts the same hydrotreating catalyst. The height of each bed layer in the reactor can be properly adjusted. When two catalyst beds are arranged in one upflow reactor, the lower part is a first bed, and the upper part is a second bed, wherein the first bed accounts for 35-50% of the total filling volume of the catalyst in the upflow reactor, and the second bed accounts for 50-65% of the total filling volume of the catalyst in the upflow reactor. When three catalyst beds are arranged in the upflow reactor, the lower part is a first bed, the middle part is a second bed, the upper part is a third bed, the first bed accounts for 20-30% of the total filling volume of the catalyst in the upflow reactor, the second bed accounts for 25-35% of the total filling volume of the catalyst in the upflow reactor, and the third bed accounts for 30-45% of the total filling volume of the catalyst in the upflow reactor. The bed height can be set to be the same or different according to different processing raw materials.

In the method for hydrotreating heavy hydrocarbon raw materials, the upflow reactor adopts the following operating conditions: the reaction pressure is 8-25 MPa, the reaction temperature is 350-420 ℃, the volume ratio of hydrogen to oil at the inlet of the upflow reactor (the ratio in the standard state, the same below) is 150: 1-350: 1, and the liquid hourly space velocity is 0.1-2.0 h^-1。

In the heavy hydrocarbon raw material hydrotreating method of the invention, 1-5, preferably 2-3 downflow fixed bed reactors can be arranged in series. One or more catalyst beds may be provided in each downflow fixed bed reactor as desired.

In the heavy hydrocarbon raw material hydrotreating method, the catalyst filled in the down-flow fixed bed reactor comprises a hydrodesulfurization catalyst and a hydrodenitrogenation catalyst, wherein the hydrodesulfurization catalyst and the hydrodenitrogenation catalyst use a porous refractory inorganic oxide as a carrier, and VIB group and/or VIII group metal as an active metal component, wherein the VIB group metal is W and/or Mo, the VIII group metal is Co and/or Ni, and preferably an additive is added, wherein the additive is one or more of P, Si, F and B.

Furthermore, the hydrodesulfurization catalyst comprises 5.0-18.0% of VIB group metal oxide and 1.5-6.0% of VIII group metal oxide by weight of the catalyst; the hydrodenitrogenation catalyst comprises 6.0-20.0% of VIB group metal and 2.0-8.0% of VIII group metal, wherein the weight of the catalyst is taken as a reference; the hydrodenitrogenation catalyst is preferably added with one or more of assistants such as P, Si and B, and the weight content of the assistants in the catalyst is less than 10%.

In the hydrotreating process of heavy hydrocarbon feedstock of the present invention, the down-flow fixed bed reactor adopts the following operating conditions: the reaction pressure is 8-25 MPa, the reaction temperature is 360-430 ℃, the volume ratio of hydrogen to oil is 500: 1-1200: 1, and the liquid hourly space velocity is 0.2-1.0 h^-1。

In the heavy hydrocarbon raw material hydrotreating method, the effluent of the down-flow type fixed bed reactor is separated to obtain products, and the products comprise light hydrocarbons, naphtha fraction, diesel fraction and tower bottom oil; the separation can be carried out by a conventional method, for example, the specific process can be as follows: the effluent of the down-flow fixed bed reactor is firstly subjected to gas-liquid separation, the obtained gas phase is mainly hydrogen, the liquid phase obtained after the gas-liquid separation of the effluent of the hydrogenation reaction enters a low-pressure separator and then enters a fractionating tower to obtain light hydrocarbons, naphtha fraction, diesel fraction and tower bottom oil, wherein the hydrogen obtained after the gas-liquid separation can be circularly used for the hydrogenation reaction after being subjected to hydrogen sulfide removal treatment, and new hydrogen can be supplemented in the hydrogenation reaction process as required.

In the heavy hydrocarbon raw material hydrotreating method, the volume ratio of the hydrotreating catalyst filled in an upflow reactor to the hydrodesulfurization catalyst and the hydrodenitrogenation catalyst filled in a downflow fixed bed reactor is 1: 0.2-5.0: 0.2 to 5.0.

The heavy hydrocarbon feedstock of the present invention includes heavy oil and/or residual oil, the residual oil can be atmospheric residual oil and/or vacuum residual oil, the heavy oil can be at least one of heavy crude oil (such as heavy oil) and other mineral oil, and the other mineral oil can be one or more selected from oil sand oil and shale oil.

Compared with the prior art, the invention has the advantages that:

1. the method of the invention fully utilizes the reaction characteristics of the upflow reactor and the downflow fixed bed reactor, coordinates and matches various functional catalysts of the upflow reactor and the downflow fixed bed reactor, further improves the cooperative and cooperative action of the combined process hydrogenation device, solves the defects that the catalyst performance synchronization can not be realized and the operation period can not be effectively prolonged when the two reactors are combined, the temperature distribution of the downflow fixed bed reactor is more reasonable, fully exerts the performance of the downflow fixed bed reactor catalyst, improves the utilization rate of the catalyst, improves the removal rate of impurities and further improves the product quality, reduces the shutdown and replacement times of the device, and obviously improves the economic benefit of the device;

2. according to the method, the upflow reactor is excellent in metal removal capacity when being filled with the catalyst, the heavy hydrocarbon raw material and hydrogen are mixed and then enter the upflow reactor, the heavy hydrocarbon raw material and the upflow hydrogenation catalyst are subjected to hydrofining reaction under a hydrotreating condition, the content of metal (Ni + V) in the upflow hydrogenation produced oil is controlled to 15-20 ppm, the carbon residue removal rate of the upflow hydrogenation produced oil is controlled to reach 30-50%, the produced oil with reduced metal and carbon residue is obtained, the downstream high-activity desulfurization and carbon residue removal catalyst can be effectively protected, metal toxicity is reduced, the catalyst can be guaranteed to reduce the deactivation influence of carbon deposition under a higher reaction temperature condition, and the long-period stable operation of the device is facilitated. The downflow fixed bed reactor is completely filled with high-activity hydrodesulfurization and hydrodenitrogenation catalysts, so that the fixed bed hydrogenation product is further subjected to deep hydrofining, the sulfur content is reduced by not more than 0.5%, the metal content is not more than 15ppm, the carbon residue is not more than 6%, the index requirements of the content of hydrogen in the hydrogenated oil of not less than 12% and the like are further met, and the deep hydroconversion capacity of impurities can be improved. In addition, the method can cancel the low-activity fixed bed demetalization catalyst bed layer, is favorable for optimizing the temperature of the fixed bed catalyst bed layer, is better matched with the temperature of the upflow catalyst bed layer, and is more favorable for the performance exertion of the catalyst and the long-period operation of the device.

3. The upflow type hydrotreating catalyst with unique appearance and pore structure provided by the invention adopts a silicon-aluminum carrier with proper granularity, pore structure and unique channel structure, so that a catalyst bed layer has higher porosity, and has good diffusion channel and reaction channel, a diffusion path of residual oil molecules is shortened, and the catalyst has higher activity, high capacity of removing metals and certain asphaltene hydroconversion capacity, namely the capacity of reducing carbon residue. The residual oil hydrotreating catalyst has greatly improved hydrogen utilization rate, and particularly under the condition of limited up-flow hydrogen, the contact probability of hydrogen with raw materials and active centers is increased, so that the utilization efficiency of the catalyst is obviously improved; in addition, the inventor also finds that the catalyst with the unique pore channel structure, which is prepared by the invention, utilizes a special molecular diffusion path, increases the residence time of reaction materials and shows excellent impurity deposition capability. In addition, in the method, a small amount of nickel salt is preferably added in the preparation process of the catalyst carrier, so that a proper amount of nickel-aluminum spinel structure is generated in the roasting process, the strength and the water resistance of the catalyst are further improved, and the catalytic performance is not influenced.

4. The upflow reactor has at least two catalyst beds filled with the same hydrotreating catalyst, and as the material property is gradually improved along the direction of reactant flow, the hydrogenation reaction is an exothermic reaction, the reaction temperature can be gradually increased, and the rear catalyst bed is in an environment with less hydrogen in the whole reaction process, the adoption of the upflow catalyst with large aperture and low hydrogen consumption is beneficial to the stability of the catalyst beds and the performance of the catalyst. In addition, the reaction temperature is gradually increased along the direction of the reactant flow, and if a catalyst with higher activity is adopted in a reaction zone with higher temperature, the partial hydrogen deficiency reaction of the bed layer is more easily caused, and the generation of hot spots of the bed layer and the fluctuation of the bed layer are easily caused. Therefore, the control of the catalyst activity can be used for the upflow reactor, so that the balance of the activity and the stability can be realized.

5. In the upflow reactor, although not as strongly back-mixed as the material in the ebullated bed reactor. However, due to the flow direction characteristics of the material flow and the micro-expansion state of the catalyst bed, if different catalyst grading technologies are adopted in the same catalyst bed in the fixed bed hydrogenation technology, bed back-mixing and bed reaction fluctuation are easily caused, and the stable operation of the device is adversely affected.

6. The up-flow type hydrotreating catalyst has good capacity of removing metals, and has the characteristics of long-period stable operation because the catalyst has higher hydrogenation capacity and simultaneously has certain capacities of removing metals, desulfurizing and converting carbon residue and asphaltene owing to the optimized pore channel design and the optimized carrier structure of the catalyst.

Drawings

FIG. 1 is a schematic cross-sectional view of a hydrotreating catalyst support preparation process in accordance with the present invention;

FIG. 2 is a schematic view of a guide die for a hydroprocessing catalyst support according to the present invention;

FIG. 3 is a schematic cross-sectional view of a hydroprocessing catalyst support according to the present invention;

FIG. 4 is a schematic process flow diagram of the present invention;

the figures 1-3 are numbered as follows:

10. a catalyst support; 100. a pasty material; 20. a mold; 30. guiding a mold; 101a, a first mandrel; 102a, a second mandrel; 103. a third channel; 103a. a third mandrel; 104a, a fourth column, 105a, a fifth column; 106a, a sixth column; 107a, seventh column.

The reference numbers of FIG. 4 are as follows:

11. a heavy hydrocarbon feedstock; 12 hydrogen gas; 13 an upflow reactor; 14, an upflow hydrogenation reaction effluent; 15 mixing hydrogen; 16 fixed bed first reaction; 17 producing oil; 18 mixing hydrogen; 19 fixed bed secondary reaction; 110 a reaction mixture; 111 a separator; 112 recycling hydrogen; 113 hydrogenation of the liquid product; a 114 pressure fractionation column; 115 light hydrocarbon gas; 116 a light naphtha fraction; 117 heavy naphtha fraction; 118 a diesel fraction; 119 bottoms; 120 compressor; 122 new hydrogen.

Detailed Description

Specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but it should be understood that the scope of the present invention is not limited to the specific embodiments.

In the invention, the specific surface area, the pore volume, the pore diameter and the pore distribution are measured by a mercury intrusion method.

In the present invention, the volume of the spherical support is (4/3) π R³Wherein R is half of the outer diameter D of the spherical support i.e. R = D/2. The total volume occupied by each channel was measured as follows: firstly, preparing the carrier to be detected and a contrast carrier, wherein the contrast carrier is prepared by the same method except that a non-porous entity is adopted to replace the part corresponding to the guide mould of the invention. Firstly, the pore volumes of the carrier and the control carrier are determined by a water titration method, then the carrier and the control carrier are respectively filled in a 100mL measuring cylinder to 100mL scales, then deionized water is added in the measuring cylinder to 100mL scales, and the pore volume of the control carrier is subtracted from the pore volume of the control carrier of 100mLThe volume of the added water minus the volume of the 100mL of the carrier of the present invention is the volume of the 100mL of the carrier particles of the present invention and the total volume of each channel, and the volume of the carrier of the present invention and the volume of the control carrier particles are considered to be the same, and the difference between the two is the total volume of each channel. Although only the guide mold is different when the control carrier is prepared, the rest part outside the channel is not completely the same as the control carrier due to decomposition of the guide mold in the carrier of the present invention, but the difference from this part is considered to be negligible in the present invention.

As shown in fig. 1 to 3, the catalyst carrier 10 of this embodiment is a spheroid structure of a paste material 100 after solidification, and a first tubular channel, a second tubular channel, and a third tubular channel 103 are arranged inside the material 100, and the first tubular channel, the second tubular channel, and the third tubular channel 103 are perpendicular to each other, and all the three tubular channels penetrate through the sphere center of the catalyst carrier 10, so that the three tubular channels are completely communicated. It should be noted that: fig. 3 of this embodiment does not clearly distinguish the individual channels, and therefore the corresponding columns are identified in fig. 2. In this embodiment, seven channels are provided, except that the first, second and third channels 103 correspond to the first mandrel 101a, the second mandrel 102a and the third mandrel 103a in fig. 2, respectively, fig. 2 also shows a fourth cylinder 104a, a fifth cylinder 105a, a sixth cylinder 106a and a seventh cylinder 107a, none of the fourth to seventh channels finally formed by the four cylinders passes through the spherical center of the catalyst carrier 10, the fourth to seventh channels are connected end to form a square channel as in fig. 2, and the four channels are not only communicated with each other, but also communicated with the first to third channels.

Referring to fig. 3, the catalyst carrier 10 of this embodiment is a spheroid structure formed by solidifying the pasty material 100, and the material 100 has a first, a second and a third tubular channels 103, which are perpendicular to each other and penetrate through the center of the catalyst carrier 10, and the three channels penetrate through the center of the catalyst carrier 10, so that the three channels are completely connected. Meanwhile, the carrier 10 is also provided with a fourth channel, a fifth channel, a sixth channel and a seventh column channel which are connected with each other in an end-to-end manner and communicated with each other, the length of the fourth channel, the fifth channel, the sixth channel and the seventh column channel is 1/3-2/3 of the diameter of the carrier 10, the fourth channel, the fifth channel, the sixth channel and the seventh column channel are square in the same plane, and the square is connected with any two of the first channel, the second channel and the third channel in the same plane. The total volume occupied by the channels is 20-60%, preferably 22-60% of the volume of the spherical carrier.

It should be noted that: the channel solutions of fig. 1-3 can also have many other variations without departing from the design concept, and are not described in detail here.

As shown in fig. 4, a heavy hydrocarbon feedstock 11 is mixed with hydrogen 12 and enters from the bottom of an upflow reactor 13, and is subjected to a hydrotreating reaction in the presence of an upflow hydrogenation catalyst, and an upflow hydrogenation effluent 14 enters a downflow fixed bed reactor, where the reactant stream is hydrotreated in a top-to-bottom flow manner in the presence of a fixed bed residue hydrogenation catalyst. The upflow hydrogenation reaction effluent 14 and mixed hydrogen 15 firstly enter the top of a first fixed bed reactor 16, first reaction hydrogenation produced oil 17 and mixed hydrogen 18 enter the top of a second fixed bed reactor 19, a reaction mixture 110 is separated and purified by a separator 111 to obtain circulating hydrogen 112 and a hydrogenation liquid phase product 113, wherein the hydrogenation liquid phase product 113 enters an atmospheric fractionating tower 114 to be fractionated to obtain light hydrocarbon gas 115, light naphtha fraction 116, heavy naphtha fraction 117, diesel fraction 118 and bottom residual oil 119. The recycle hydrogen 112 is mixed with fresh hydrogen 122 by the compressor 120 and used in each reactor, and the distribution of hydrogen is determined according to the reaction conditions and the temperature control of the reactor.

In the present invention, percentages and percentages are by mass unless otherwise specifically indicated.

In the present invention, unless otherwise specifically stated, the reaction temperature described in the specification may specifically refer to the average temperature described in the examples and comparative examples.

Throughout the specification and claims, unless explicitly described otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated step or element but not the exclusion of any other step or element.

The present invention is further illustrated by the following examples, but it should be understood that the scope of the present invention is not limited by the examples.

Example 1

Preparation of an upflow hydrogenation catalyst:

1071g of water glass with the silicon oxide content of 28wt% is weighed and added into a beaker, a stirring device is started, 370g of nitric acid solution with the mass concentration of 65% is slowly added into the beaker, the pH value of the water glass solution in the beaker after stirring and dissolving is 2.0, 93.14g of nickel nitrate hexahydrate is added, 585g of alumina sol (with the following properties, the Al/Cl ratio is 1.40, the aluminum oxide content is 28 wt%) and gamma-Al are added into the solution after dissolving₂O₃163.8g (properties are as follows: pore volume is 1.098mL/g, specific surface area is 302m²And/g), stirring uniformly, adding 93.6g of hexamethylene tetramine as a curing agent, adding deionized water after the hexamethylene tetramine is completely dissolved, and enabling the materials in the beaker to be in a paste shape with certain fluidity and the solid content of the materials calculated by silicon dioxide and aluminum oxide to be 33%.

The pasty material is pressed into two identical hemispheres with spherical cavities. Wherein a guide die is placed in one hemisphere, and the guide die is made of wood. The structure of the guide die is that three cylinders are made of the material, the length of each cylinder is the diameter of a cavity, the centers of the three cylinders are intersected and perpendicular in pairs, and then four cylinders are made of the material, wherein the fourth cylinder, the fifth cylinder, the sixth cylinder and the seventh cylinder are connected end to end and communicated, the fourth cylinder, the fifth cylinder, the sixth cylinder and the seventh cylinder are square in the same plane, and the square is connected with any two of the first cylinder, the second cylinder and the third cylinder in the same plane. See the cross-sectional view of the center of the sphere of fig. 3. The pasty material is pressed into the two hemispheroidal cavities, and the two hemispheroids are combined together to form a complete sphere and fixed after the whole cavity is filled with the pasty material.

Heating the ball containing the paste material to 120 ℃, keeping the temperature for 60 minutes, releasing ammonia gas after the paste material is heated to enable the paste material to be solidified and contracted, then automatically demoulding to form spherical gel, washing the spherical gel to be neutral by deionized water, drying for 5 hours at 120 ℃, and roasting for 3 hours at 700 ℃. And burning the guide die which can form the through channel in the roasting process, and leaving the through channel required by the catalyst, thereby obtaining the spherical catalyst carrier A. The outer diameter of the obtained catalyst carrier A is about 5.5mm, wherein the lengths of the first channel, the second channel and the third channel are 5.5mm, and the diameter of the channels is about 1.6 mm; the length of the fourth channel, the fifth channel, the sixth channel and the seventh channel forming the square channel is 4mm, and the diameter of the channels is about 0.6 mm.

Soaking the carrier A in Mo-Ni-P solution, drying at 120 deg.c for 6 hr, and roasting at 500 deg.c for 3 hr to obtain the hydrogenation catalyst A_CThe catalyst properties are shown in Table 1.

Example 2

The preparation process was as in example 1 except that 97.2g of urea was added instead of hexamethylenetetramine as the curing agent and 62.5g of nickel nitrate hexahydrate were added instead, and the hydrogenation catalyst carrier B and the hydrogenation catalyst B were prepared_CThe properties are shown in Table 1.

Wherein the outer diameter of the obtained catalyst carrier B is about 5.5mm, the diameters of the through holes of the first channel, the second channel and the third channel are about 1.5mm, and the lengths of the first channel, the second channel and the third channel are 5.5 mm; the fourth, fifth, sixth and seventh channels forming the square channels were all 4.2mm in length and approximately 0.8mm in channel diameter.

Example 3

The preparation process is as in example 1, except that the mold is changed, the diameters of the cavity and the column are increased, and the prepared hydrogenation catalyst carrier C and the hydrogenation catalyst C are adopted_CThe properties are shown in Table 1.

Wherein the outer diameter of the obtained catalyst carrier C is about 7.5mm, the diameters of the through holes of the first channel, the second channel and the third channel are about 2.6mm, the lengths of the first channel, the second channel and the third channel are 7.5mm, the lengths of the fourth channel, the fifth channel, the sixth channel and the seventh channel which form the square channels are all 6mm, and the diameter of the channels is about 1.3 mm.

Example 4

The preparation process was as in example 1 except that nickel nitrate was not added, and a hydrogenation catalyst support D and a hydrogenation catalyst D were prepared_CThe properties are shown in Table 1.

The outer diameter of the obtained catalyst carrier D is about 5.5mm, the diameter of the through hole is about 1.6mm, the lengths of the first channel, the second channel and the third channel are 5.5mm, the lengths of the fourth channel, the fifth channel, the sixth channel and the seventh channel which form the square channels are 4mm, and the diameter of the channels is about 0.6 mm.

Comparative example 1

The pasty material is pressed into two identical hemispheres with spherical cavities. The pasty material is pressed into the two hemispheroidal cavities, and the two hemispheroids are combined together to form a complete sphere and fixed after the whole cavity is filled with the pasty material.

Heating the sphere containing the paste material to 120 ℃, keeping the temperature for 60 minutes, releasing ammonia gas after the paste material is heated to enable the paste material to be solidified and contracted, then automatically demoulding to form spherical gel, washing the spherical gel to be neutral by deionized water, drying for 5 hours at 120 ℃, and roasting for 3 hours at 700 ℃ to obtain the spherical catalyst carrier E of the comparative example. The outer diameter of the obtained catalyst carrier E was about 5.5 mm.

The carrier E was impregnated with the Mo-Ni-P solution, dried at 120 ℃ for 6 hours, and calcined at 500 ℃ for 3 hours to obtain the hydrogenation catalyst Ec of this comparative example, the catalyst properties of which are shown in Table 1.

Example 5

In this example, an upflow reactor and three downflow fixed bed reactors were provided, all of which were located downstream of the upflow reactor and were used in series in this order. The upflow hydrogenation produced oil and mixed hydrogen are mixed and then sequentially pass through the three fixed bed reactors.

The upflow reactor is provided with two equal-volume catalyst beds, each catalyst bed is filled with 350 mL of catalyst, the total amount of the catalyst is 700mL, and each bed is filled with the same catalyst. The upflow reactor respectively adopts upflow hydrotreating catalyst A_C、B_C、C_C、D_CAnd E_C. The three fixed bed reactors are all single catalyst bed layers.

The raw material is typical middle east residual oil, and hydrogenation modification reaction is carried out in an upflow residual oil hydrogenation reactor, and upflow hydrogenation generated oil is obtained after impurities such as metal and the like are mainly removed. The fixed bed comprises three reactors, wherein one reactor is reversely filled with 240mL of desulfurization catalyst FZC-34A, the other reactor is reversely filled with 140 mL of desulfurization catalyst FZC-34A and 100mL of denitrification catalyst FZC-41A, the other reactor is reversely filled with 240mL of denitrification catalyst FZC-41A, and the properties of the desulfurization catalyst FZC-34A and the denitrification catalyst FZC-41A are shown in Table 2. And further carrying out hydrotreatment to obtain fixed bed hydrogenation reaction generated oil. The main process conditions are detailed in table 3. The properties of the hydroprocessed oil from the upflow reactor versus the downflow reactor are shown in Table 4, where Ac (up), Bc (up), Cc (up), Dc (up), and E_C(upper) means the upflow hydrogenated product oil, Ac (lower), Bc (lower), Cc (lower), Dc (upper) and E_CThe term "upper" refers to the downflow fixed bed hydrogenation of the product oil.

Example 6

The same as example 5, wherein the upflow reactor used hydrotreating catalyst A_CAnd three catalyst beds were used, and the properties of the product obtained by the reaction are shown in Table 5. The first catalyst bed layer of the upflow reactor is filled with 200mL of catalyst, the second catalyst bed layer of the upflow reactor is filled with 250 mL of catalyst, and the third catalyst bed layer of the upflow reactor is filled with catalyst250 mL, the total catalyst loading was 700 mL. The fixed bed comprises three reactors, wherein the first reverse packed desulfurization catalyst FZC-34A is 240mL, the second reverse packed desulfurization catalyst FZC-34A is 100mL, the denitrification catalyst FZC-41A is 140 mL, and the third reverse packed denitrification catalyst FZC-41A is 240 mL.

Comparative example 2

In this comparative example, one upflow reactor and three downflow fixed bed reactors were also provided, and the volumes of the reactors were identical. Wherein, the filled catalyst and the filled process are obtained by adopting the conventional method in the field.

The upflow reactor adopts a double-bed arrangement, the volumes of two beds are the same, 300mL of catalyst is filled in the two beds, and 600 mL of catalyst is filled in the two beds. The upflow hydrogenation catalysts FZC10UH and FZC11UH were charged separately. FZC10UH is a conventional upflow demetallization catalyst, FZC11UH is a high activity upflow hydrodemetallization desulfurization catalyst, and the catalyst properties are shown in table 2. Mixing a hydrogenation product obtained by an upflow reactor with hydrogen, and then carrying out a hydrotreating reaction in the presence of a fixed bed residual oil hydrogenation catalyst, wherein the fixed bed comprises three reactors, a demetallization catalyst FZC-28A is reversely filled, the filling volume is 200mL, and a desulfurization catalyst FZC-34A is 40 mL; a secondary reverse desulfurization catalyst FZC-34A with the filling volume of 240 mL; the loading volume of the three-reaction denitrification catalyst FZC-41A is 240 mL. And further carrying out hydrotreatment to obtain fixed bed hydrogenation reaction generated oil. The main process conditions are detailed in Table 3, and the properties of the product obtained by the reaction are shown in Table 5.

TABLE 1 Properties of the supports and catalysts prepared in examples and comparative examples

Catalyst support numbering	Carrier A	Carrier B	Carrier C	Carrier D	Carrier E
						Pore volume, mL/g	0.814	0.808	0.813	0.815	0.784
Specific surface area, m²/g	139	141	137	141	153
						Average pore diameter, nm	23.4	22.9	23.7	23.1	20.5
Hole distribution,%
						<8.0nm	0.8	0.7	0.7	0.5	1.6
8-16 nm	34.5	34.3	34	34.4	39.3
						16-100 nm	58.1	58.1	58.7	58.9	52.1
>100.0nm	6.6	6.9	6.6	6.2	7
						Catalyst numbering	A_C	B_C	C_C	D_C	E_C
Metal content%
						MoO₃	8.5	8.7	8.3	8.4	8.6
NiO	5.1	4.3	5.0	2.1	5.1
						Lateral pressure strength, N/grain	45	38	34	30	87

TABLE 2 Properties of the hydrogenation catalysts used in the comparative examples

Catalyst brand	FZC-28A	FZC-34A	FZC-41A	FZC-10U	FZC-11U
						Function(s)	Demetallization catalyst	Desulfurization catalyst	Denitrification catalyst	Demetallization catalyst	Desulfurization catalyst
Particle shape	2-8mm strip	2-8mm strip	2-8mm strip	Spherical shape	Spherical shape
						Outer diameter of the granule mm	1.55	1.20	1.3	2.9	2.9
Strength, N.mm^-1	16	20	26	32	30
						Specific surface area, m²/g	133	182	228	110	148
Wear rate, wt%	1.32	0.92	0.76	0.3	0.4
						Metal content, wt.%
MoO₃	7.83	12.67	18.70	5.2	10.8
						NiO	2.04	3.95	4.32	1.2	2.4

TABLE 3 Main operating conditions of examples and comparative examples

Item	Example 5	Example 5	Example 5	Example 5	Example 5	Comparative example 2
							Upflow catalyst numbering	A_C	B_C	C_C	D_C	E_C	FZC10UH and FZC11UH
A reverse inlet pressure, MPa	16.6	16.6	16.6	16.6	16.6	16.6
							Total volume space velocity, h^-1	0.195	0.195	0.195	0.195	0.195	0.195
Operating conditions of UFR reactor
							Liquid hourly volume space velocity, h^-1	0.395	0.395	0.395	0.395	0.395	0.395
Inlet gas-oil ratio	300	300	300	300	300	300
							Reaction temperature of	380	381	381	380.5	379.5	378
Operating conditions of a downflow fixed bed reactor
							Liquid hourly volume space velocity, h^-1	0.385	0.385	0.385	0.385	0.385	0.385
Inlet gas-oil ratio	650	650	650	650	650	650
							Reaction temperature of	386	386	386	386	386	390
Temperature rise distribution of each reactor of fixed bed
							First temperature rise, second temperature	11	12	11	12	_	8
Second heating and second heating	16	15	14	15	_	17
							Three raising the temperature and the temperature	17	17	15	16	_	14

Table 4 main properties of the feedstock, upflow and fixed bed hydrogenation to oils used in example 5

Item	Raw materials	Ac (Upper)	Ac (lower)	Bc (Upper)	Bc (lower)
						S，wt%	2.85	1.13	0.43	1.18	0.46
N，μg/g	4020	2780	1877	2832	1912
						CCR，wt%	11.35	7.28	5.20	7.36	5.39
Density (20 ℃), kg/m³	986.7	954.3	935.4	954.2	935.6
						Viscosity (100 ℃ C.), mm²/s	90.5	47.51	27.88	45.35	29.96
Ni+V，µg/g	68.7	19.60	12.33	18.71	12.36

TABLE 4 (continuation) essential properties of the feedstock, upflow and fixed bed hydrorefining oils used in example 5

Item	Cc (Upper)	Cc (lower)	Dc (Upper)	Dc (lower)	Ec (Upper)	Ec (lower)
							S，wt%	1.17	0.44	1.22	0.50	1.38	0.52
N，μg/g	2853	1920	2882	1985	2934	2130
							CCR，wt%	7.37	5.27	7.52	5.50	8.43	6.21
Density (20 ℃), kg/m³	954.5	935.5	956.5	936.0	959.7	937.2
							Viscosity (100 ℃ C.), mm²/s	46.66	28.84	47.6	31.36	44.73	34.2
Ni+V，µg/g	19.04	12.32	24.74	15.73	28.43	16.22

TABLE 5 main properties of the feedstocks, upflow and fixed bed hydrogenated oils used in example 6 and comparative example 2

Item	Raw materials	Example 6	Example 6	Comparative example 2	Comparative example 2
								Upflow hydrogenation to produce oil	Fixed bed hydrogenation of residual oil	Upflow hydrogenation to produce oil	Fixed bed hydrogenation of residual oil
S，wt%	2.85	1.14	0.42	1.46	0.49
						N，μg/g	4020	2635	1832	2930	2184
Carbon Residue (CCR), wt%	11.35	7.23	4.64	7.92	5.86
						Density (20 ℃), kg/m³	986.7	954.2	935.1	956.7	937.5
Viscosity (100 ℃ C.), mm²/s	90.5	45.32	27.17	47.34	33.64
						Ni+V，µg/g	68.7	18.67	12.05	33.45	14.46

Example 7

Testing of hydrogenation stability of residual oil, in order to further examine the stability of the process technology of the present invention, stability life tests were respectively performed on the above example 6 and comparative example 2, and the reaction results are shown in table 6.

TABLE 6 residual oil hydrogenation stability test

Item/run time	Catalyst and process for preparing same	Upflow/fixed bed formation oil	500h	1000h	2000h	3000h	4000h	5000h	Fixed bed oil product index
										Product oil S, wt%	Example 6	Upflow oil production	1.14	1.15	1.16	1.19	1.22	1.24
Product oil S, wt%	Example 6	Fixed bed oil production	0.42	0.43	0.43	0.44	0.45	0.46	≤0.50
										Product oil S, wt%	Comparative example 2	Upflow oil production	1.46	1.47	1.53	1.56	1.63	1.83
Product oil S, wt%	Comparative example 2	Fixed bed oil production	0.49	0.55	0.57	0.66	0.69	0.72	≤0.50
										Resulting oil CCR, wt%	Example 6	Upflow oil production	7.23	7.26	7.43	7.51	7.52	7.67
Resulting oil CCR, wt%	Example 6	Fixed bed oil production	4.64	4.66	4.67	4.72	4.75	4.82	≤6.0
										Resulting oil CCR, wt%	Comparative example 2	Upflow oil production	7.92	7.99	8.21	8.37	8.56	8.84
Resulting oil CCR, wt%	Comparative example 2	Fixed bed oil production	5.86	5.98	6.22	6.48	6.92	7.42	≤6.0
										Oil (Ni + V) formation, mug/g	Example 6	Upflow oil production	18.67	18.82	18.83	19.75	19.7	19.88	≤20.00
Oil (Ni + V) formation, mug/g	Example 6	Fixed bed oil production	12.05	12. 54	12.58	12.86	13.12	13.72	≤15.00
										Oil (Ni + V) formation, mug/g	ComparisonExample 2	Upflow oil production	33.45	34.70	34.54	36.62	37.20	38.64
Oil (Ni + V) formation, mug/g	Comparative example 2	Fixed bed oil production	14.46	15.04	16.64	17.22	17.86	18.33	≤15.00

From Table 6, in example 6, the good demetallization capability is maintained in the upflow mode, and the removal of the oil metal (Ni + V) generated in the upflow hydrogenation is carried out until the removal rate is less than 20 [ mu ] g/g. In comparative example 2, the up-flow type oiling metal (Ni + V) is increased to 38.6 mug/g after 5000 hours, and the oiling metal (Ni + V) of the fixed bed exceeds 18 mug/g and exceeds the requirement of the index of 15.0 mug/g. It can be seen that the upflow demetallization performance of example 6 is outstanding, good stability is still shown even after 5000 hours, the performance matching with the fixed bed catalyst is good, the sulfur content of the final fixed bed generated oil is 0.46 wt%, the carbon residue value is 4.82wt%, and the metal (Ni + V) is less than 15 mug/g.

The upstream type catalyst in the comparative example 2 has higher inactivation speed, the demetallization capability is greatly reduced due to the higher upstream type inactivation speed in 4000 hours, and the rear high-activity catalyst is poisoned, so that the overall performance is insufficient, and the sulfur content of the oil generated by the fixed bed is 0.69 wt%, and the requirement of the index of 0.50 wt% is also met; the method is also embodied in the removal of carbon residue, and the carbon residue value of the upflow generated oil is greatly increased to 8.84 wt% by 5000 hours, so that the performance of the fixed bed catalyst is difficult to make up the loss of the upflow activity and exceeds the requirement of 6.00 wt% of the index.

Therefore, it can be seen from Table 6 that the properties of the product oil of the present invention are significantly improved as compared with the conventional process of the comparative example, and the hydrogenation activity and stability of the present invention are also better than those of the comparative example, so that the service life of the catalyst can be prolonged.

Claims

1. A process for the hydroprocessing of heavy hydrocarbon feedstocks, comprising: at least one upflow reactor and at least one downflow fixed bed reactor are connected in series, the heavy hydrocarbon raw material sequentially passes through the upflow reactor and the downflow fixed bed reactor, and the effluent of the downflow fixed bed reactor is separated to obtain each product;

wherein the upflow reactor is filled with at least one of the following hydrotreating catalysts: the hydrotreating catalyst comprises a carrier and an active component, wherein the carrier is spherical, the outer diameter of the spherical carrier is 5.0-10.0 mm, the carrier at least comprises seven channels which penetrate through the carrier, namely a first channel, a second channel, a third channel, a fourth channel, a fifth channel, a sixth channel and a seventh channel, the first channel, the second channel and the third channel penetrate through the sphere center of the catalyst carrier and are communicated with each other, the first channel, the second channel and the third channel are vertical in pairs, the fourth channel, the fifth channel, the sixth channel and the seventh channel are connected and communicated end to end, and the total volume of the channels accounts for 20-60% of the volume of the spherical carrier, preferably 22-60%.

2. The method of claim 1, wherein in the carrier, the fourth channel, the fifth channel, the sixth channel and the seventh channel are square in the same plane, forming a square channel; preferably, the square channel and any two of the first channel, the second channel and the third channel are in the same plane and communicated with the square channel; still more preferably, the length of the fourth, fifth, sixth or seventh channels forming the square channels is at least 1/3 to 2/3 of the outer diameter of the carrier sphere.

3. Method according to claim 1, wherein the cross-section of the channels in the carrier is circular, polygonal, oval or profiled, preferably circular.

4. The method according to claim 1, wherein in the carrier, each channel is a straight channel, and the cross-sectional area of each channel is the same shape, preferably, circular; preferably, the diameters of the first channel, the second channel and the third channel are the same, and the diameters of the fourth channel, the fifth channel, the sixth channel and the seventh channel are the same; and the maximum diameter of the fourth channel, the fifth channel, the sixth channel or the seventh channel is 20-80%, preferably 35-65% of the minimum diameter of the first channel, the second channel or the third channel.

5. The method of claim 1, wherein the hydrotreating catalyst is Al₂O₃-SiO₂As a carrier, wherein SiO₂The weight content is 35-80%, preferably 40-60%.

6. The method of claim 5, further comprising a first metal component oxide in the support, wherein the first metal component oxide is NiO.

7. The method of claim 6, wherein the first metal component oxide NiO is mixed with Al in the carrier₂O₃Is 0.03: 1-0.13: 1, preferably 0.05: 1-0.11: 1.

8. the method according to any one of claims 1 to 7, wherein the carrier has the following properties: the specific surface area is 80-200 m²A pore volume of 0.78mL/g or more, preferably 0.78 to 1.15mL/g, the pore volume occupied by the pore diameter of 16-100 nm is 35% -60% of the total pore volume, and the average pore diameter is more than 18nm, preferably 20-30 nm.

9. The method of claim 1, wherein the active metal component of the hydrotreating catalyst comprises a second metal component, i.e., a group vib metal element, preferably Mo, and a third metal component, i.e., a group viii metal element, preferably Ni and/or Co.

10. The method of claim 9, wherein the second metal component is present in an amount of 1.0% to 10.0%, preferably 1.5% to 9%, calculated as oxide, and the total amount of the first metal component and the third metal component is present in an amount of 1.0% to 10.0%, preferably 2.0% to 8.0%, calculated as oxide, and the amount of silica is 35.0% to 55.0%, and the amount of alumina is 35.0% to 55.0%, based on the weight of the catalyst.

11. The method of claim 1, wherein the one upflow reactor is provided with 2-5 catalyst beds, and each catalyst bed uses the same hydrotreating catalyst.

12. The method as claimed in claim 1 or 11, wherein when two catalyst beds are arranged in the upflow reactor, the lower part is a first bed and the upper part is a second bed, wherein the first bed accounts for 35-50% of the total filling volume of the catalyst in the upflow reactor, and the second bed accounts for 50-65% of the total filling volume of the catalyst in the upflow reactor.

13. The method as claimed in claim 1 or 11, wherein when three catalyst beds are provided in the upflow reactor, the lower part is the first bed, the middle part is the second bed, and the upper part is the third bed, the first bed accounts for 20% -30% of the total catalyst loading volume in the upflow reactor, the second bed accounts for 25% -35% of the total catalyst loading volume in the upflow reactor, and the third bed accounts for 30% -45% of the total catalyst loading volume in the upflow reactor.

14. The process according to claim 1, characterized in that the upflow reactor is operated under the following conditions: the reaction pressure is 8-25 MPa, the reaction temperature is 350-420 ℃, the volume ratio of hydrogen to oil at the inlet of the upflow reactor is 150: 1-350: 1, and the liquid hourly space velocity is 0.1-2.0 h^-1。

15. The method according to claim 1, wherein 1 to 5, preferably 2 to 3, downflow fixed bed reactors are arranged in series; one or more catalyst beds are provided in each downflow fixed bed reactor.

16. The method according to claim 1, wherein the catalyst filled in the downflow fixed bed reactor comprises a hydrodesulfurization catalyst and a hydrodenitrogenation catalyst, wherein the hydrodesulfurization catalyst and the hydrodenitrogenation catalyst use a porous refractory inorganic oxide as a carrier, and a group VIB and/or group VIII metal as an active metal component, wherein the group VIB metal is W and/or Mo, the group VIII metal is Co and/or Ni, and preferably an additive is added, wherein the additive is one or more of P, Si, F and B.

17. The method of claim 16, wherein the hydrodesulfurization catalyst comprises, by weight of the catalyst, from 5.0% to 18.0% by weight of group VIB metal oxide and from 1.5% to 6.0% by weight of group VIII metal oxide; the hydrodenitrogenation catalyst comprises 6.0-20.0% of VIB group metal and 2.0-8.0% of VIII group metal, wherein the weight of the catalyst is taken as a reference; the hydrodenitrogenation catalyst is preferably added with one or more of assistants such as P, Si and B, and the weight content of the assistants in the catalyst is less than 10%.

18. According to the rightThe process of claim 1, wherein the downflow fixed bed reactor is operated under the following conditions: the reaction pressure is 8-25 MPa, the reaction temperature is 360-430 ℃, the volume ratio of hydrogen to oil is 500: 1-1200: 1, and the liquid hourly space velocity is 0.2-1.0 h^-1。

19. The method of claim 1, wherein the separation of the downflow fixed bed reactor effluent is performed by: the effluent of the down-flow fixed bed reactor is firstly subjected to gas-liquid separation to obtain a gas phase of hydrogen, a liquid phase obtained after the gas-liquid separation of the effluent of the hydrogenation reaction enters a low-pressure separator and then enters a fractionating tower to obtain products, wherein the products comprise light hydrocarbons, naphtha fraction, diesel fraction and tower bottom oil, and the hydrogen obtained after the gas-liquid separation is subjected to hydrogen sulfide removal treatment and then is recycled for the hydrogenation reaction.

20. The method of claim 16, wherein the ratio of the volume of hydroprocessing catalyst loaded in the upflow reactor to the volume of hydrodesulfurization catalyst and hydrodenitrogenation catalyst loaded in the downflow fixed bed reactor is 1: 0.2-5.0: 0.2 to 5.0.