Method for hydrotreating heavy hydrocarbon raw material by adopting up-flow reactor
Technical Field
The invention relates to a hydrocarbon raw material hydrotreating technology, in particular to a method for hydrotreating heavy hydrocarbon raw materials by adopting an upflow reactor.
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, reactor types can be classified into general fixed bed reactors, i.e., a downflow mode reactor and an Upflow (UFR) reactor, according to the flow pattern of the reactant stream in the reactor. 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 in the reactor is always in a micro-expansion state under 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 upflow reactor (UFR) is generally arranged in front of the fixed bed reactor (downflow mode), which can greatly reduce the metal content in the feed entering the downflow fixed bed reactor, protect the fixed bed reactor catalyst and prevent the premature deactivation thereof. The upflow reaction has the technical characteristics that reactant flows from bottom to top, so that a catalyst bed layer is slightly expanded, and the pressure drop is small, thereby solving the problem of large pressure drop change at the initial stage and the final stage when the conventional fixed bed reactor processes inferior residual oil. The upflow reactor can better remove metal impurities so as to protect a downstream fixed bed reactor and prolong the running period of the device. The combined process can fully exert the respective advantages of the upflow reaction zone and the fixed bed reactor.
Hydrodesulfurization and demetalization are two important reactions in the hydrogenation process of heavy raw oil such as residual oil and the like, and are also main targets of heavy oil hydrogenation modification. A difficulty in residual oil processing is asphaltene conversion. The chemical structure of the asphaltene is very complex, and the asphaltene is composed of polymerized aromatic hydrocarbon, alkane chain and naphthene ring, and has very large molecular weight, and the average molecular size is about 6-9 nm. The asphaltene structure also contains heteroatoms such as sulfur, nitrogen, metal and the like, and 80-90% of the metal in the crude oil is enriched in the asphaltene. These impurities are "buried" within the molecule and require harsh operating conditions to remove the impurities. The rate of asphaltene decomposition during hydrogenation is related to the pore size of the catalyst used. The pore diameter of the catalyst is at least larger than 10nm, and the asphaltene is possibly diffused into the pore channels of the catalyst. The catalyst also needs to have a larger pore volume to improve diffusion performance and to accommodate more impurities. Thus, for the treatment of macromolecular compounds, the pore structure of the catalyst appears to be critical: the catalyst should have a certain number of macropores, so that larger asphalt molecules can easily approach the inner surface of the catalyst, and the maximum hydrodemetallization degree can be achieved. But the number of macropores cannot be too large, otherwise, the specific surface area is reduced, and the desulfurization activity is obviously reduced.
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. In the upflow reactor, the activity of the catalyst in the upflow reactor is gradually increased along the material flow direction, the hydrogen consumption of the high-activity catalyst bed is gradually increased, the heat release is increased, and the upflow reactor is easy to cause the local hydrogen deficiency of the catalyst bed and the disturbance of the bed due to the limitation of the hydrogen-oil ratio, thereby easily causing the generation of hot spots. In addition, because the capability of the catalyst for depositing metal is insufficient, the deactivation is accelerated, thereby influencing the performance of the catalyst and the operation period of the device.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a method for hydrotreating heavy hydrocarbon raw materials by adopting an up-flow reactor, wherein catalysts with different shapes of channels are respectively adopted in a low-temperature area and a high-temperature area for grading filling, the performances of the respective catalysts are exerted, and the operation period of the device is greatly prolonged.
The invention provides a method for hydrotreating heavy hydrocarbon raw materials by adopting an up-flow reactor, which comprises the steps of adopting at least one up-flow reactor, wherein at least two catalyst bed layers of a low-temperature area and a high-temperature area are arranged in the one up-flow reactor, and hydrotreating catalysts with channels in different shapes are respectively loaded in a grading manner; the hydrotreating catalyst filled in the bed layer of the low temperature region and the hydrotreating catalyst filled in the bed layer of the high temperature region both comprise carriers and active components, wherein the carriers are spherical, the outer diameter of each spherical carrier is 5.0-10.0 mm, the carriers internally comprise channels, and the total volume of the channels is 20-60% of the volume of the spherical carriers, preferably 28-60%;
the hydrotreating catalyst carrier filled in the bed layer of the low temperature zone comprises five channels which penetrate through the carrier, namely a first channel, a second channel, a third channel, a fourth channel and a fifth channel, wherein the five channels 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, and the first channel, the second channel, the fourth channel and the fifth channel are integrally shaped like a Chinese character 'mi';
the hydrotreating catalyst carrier filled in the high-temperature zone bed layer comprises six channels penetrating through the carrier, namely a first channel, a second channel, a third channel, a fourth channel, a fifth channel and a sixth channel, wherein the first channel, the second channel, the third channel, the fourth channel and the fifth 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 sixth channel is arranged between the fourth channel and the fifth channel, is intersected and communicated with the fourth channel and the fifth channel and does not pass through the sphere center, and the first channel, the second channel, the fourth channel, the fifth channel and the sixth channel are integrally shaped like a Chinese character 'lai'.
Further, the minimum angle between the fourth channel and the fifth channel of the hydrotreating catalyst carrier filled in the bed layer of the low temperature zone or the high temperature zone is more than 40 degrees, and the minimum angle between the fourth channel or the fifth channel and the first channel, the second channel or the third channel is more than 20 degrees.
Furthermore, the cross section of the hydrotreating catalyst carrier channel filled in the bed layer of the low-temperature area or the high-temperature area is circular, polygonal, elliptical or special, preferably circular.
Furthermore, a fourth channel and a fifth channel in the hydrotreating catalyst carrier filled in the bed layer of the low-temperature area or the high-temperature area are positioned in the same plane with any two of the first channel, the second channel or the third channel; preferably, the fourth channel and the fifth channel are uniformly distributed at an angle with the first channel, the second channel or the third channel in the same plane.
Further, the channels in the hydrotreating catalyst carrier filled in the bed layer of the low-temperature zone or the high-temperature zone are straight channels, preferably, the first channel, the second channel, the third channel, the fourth channel and the fifth channel have the same cross-sectional shape, preferably circular cross-sectional area.
Furthermore, the sixth channel, the fourth channel and the fifth channel of the hydrogenation catalyst carrier filled in the bed layer of the high temperature zone are intersected and communicated, and the distance between the intersection point and the sphere center accounts for 1/3-3/4 of the sphere radius of the carrier.
Furthermore, the hydrotreating catalyst filled in the bed layer of the low-temperature zone or the high-temperature zone is Al2O3-SiO2As a carrier, wherein SiO2The weight content is 35-80%, preferably 40-60%.
Furthermore, the hydrotreating catalyst carrier filled in the bed layer of the low-temperature area or the high-temperature area also contains a first metal component oxide, and the first metal component oxide is NiO.
Furthermore, in the hydrotreating catalyst filled in the bed layer of the low-temperature zone or the high-temperature zone, the first metal component oxides NiO and Al2O3Is 0.03: 1-0.13: 1, preferably 0.05: 1-0.11: 1.
further, said low temperatureThe properties of the hydrotreating catalyst support packed in the bed of the zone or high temperature zone are as follows: the specific surface area is 80-200 m2The pore volume is more than 0.78mL/g, preferably 0.78-1.15 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.
Further, the active metal components in the hydrotreating catalyst filled in the bed layer of the low temperature zone or the high temperature zone comprise 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.
Further, in the hydrotreating catalyst filled in the bed layer of the low temperature zone or the high temperature zone, the content of the second metal component calculated by oxide is 1.0% -10.0%, preferably 1.5% -7.5%, the total content of the first metal component and the third metal component calculated by oxide is 1.0% -10.0%, preferably 1.4% -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, wherein the shell is made of rigid materials, and the external shape can be any shape, preferably a symmetrical geometric shape such as a sphere. 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 catalyst particles and can be 5.0-16.0 mm. 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, five cylinders are made of the above materials, the length of the cylinder is the diameter of the cavity, the centers of the three cylinders are intersected and perpendicular in pairs, the center of the fourth cylinder is intersected with the center of the fifth cylinder, the minimum angle between the two cylinders is more than 40 degrees, and the minimum angle between the fourth cylinder or the fifth cylinder and any two cylinders in the first three cylinders is more than 20 degrees. Meanwhile, the fourth cylinder and the fifth cylinder can be in the same plane with any two cylinders of the first three cylinders, or not in the same plane, preferably, the fourth cylinder and the fifth cylinder are in the same plane with any two cylinders of the first three cylinders, and further, the fourth cylinder and the fifth cylinder are uniformly distributed with any two cylinders of the first three cylinders in the same plane. Meanwhile, the total volume occupied by each channel is ensured to be 20-60 percent of the volume of the spherical carrier, preferably 30-60 percent, the structure of the guide die is matched with each through hole channel in the carrier, namely the channel generated after the guide die is removed.
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 preparation method of the hydrotreating catalyst, the temperature for heating the paste-like material containing mold in the step (3) is 70-200 ℃, preferably 100-150 ℃, and the constant temperature time is 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 method for hydrotreating heavy hydrocarbon raw materials by using the upflow reactor, 2-5 catalyst beds are arranged in one upflow reactor, and each catalyst bed adopts the hydrotreating catalyst with channels in different shapes. The height of each bed layer in the reactor can be properly adjusted.
Further, when two catalyst beds are arranged in one upflow reactor, the lower part is a low-temperature zone bed, and the upper part is a high-temperature zone bed, wherein the low-temperature zone bed accounts for 35-50% of the total filling volume of the catalyst in the upflow reactor, and the high-temperature zone bed accounts for 50-65% of the total filling volume of the catalyst in the upflow reactor.
Further, when three catalyst beds are arranged in the upflow reactor, the lower part is a low-temperature zone bed, the middle part is a high-temperature zone bed, and the upper part is a second high-temperature zone bed; and the hydrotreating catalyst carrier filled in the second high-temperature zone bed layer is additionally provided with a seventh channel on the hydrotreating catalyst carrier in the high-temperature zone bed layer, wherein the seventh channel is arranged between the fourth channel and the fifth channel, is intersected and communicated with the fourth channel and the fifth channel, and the distance between the intersection point and the sphere center accounts for 1/3-3/4 of the sphere radius of the carrier, and is respectively positioned at two sides of the sphere center together with the sixth channel.
Further, the low-temperature zone bed layer accounts for 20-30% of the total filling volume of the catalyst in the upflow reactor, the high-temperature zone bed layer accounts for 25-35% of the total filling volume of the catalyst in the upflow reactor, and the second high-temperature zone bed layer accounts for 30-45% of the total filling volume of the catalyst in the upflow reactor.
Further, the upflow reactor employed the following operating conditions: the reaction pressure is 5-25 MPa, the reaction temperature is 300-420 ℃, and the liquid hourly space velocity is 0.05-5.0 h-1The volume ratio of hydrogen to oil is 150: 1-400: 1.
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 following beneficial effects:
1. the upflow type hydrotreatment reactor is filled with the hydrotreatment catalyst with a unique appearance and a pore structure, and the catalyst adopts a silicon-aluminum carrier with proper granularity, a pore channel structure and a unique channel structure, so that a catalyst bed layer has higher porosity on one hand, and good diffusion channels and reaction channels on the other hand. The catalyst in the low-temperature zone has a better diffusion channel, shortens the diffusion path of residual oil molecules, and has higher activity, the hydrogen utilization rate of the residual oil hydrotreating catalyst is greatly improved, 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. The catalyst with complicated internal channels is adopted in the high-temperature zone, and the catalyst is directly communicated with the pore channels in the catalyst, and other channels in the catalyst prolong the retention time of the raw oil in the catalyst, so that a good impurity removal effect can be obtained.
2. By adopting the method, at least two catalyst beds and hydrotreating catalysts with different pore channel shapes are filled in the upflow reactor to play different functions. Because the material property is gradually improved along the direction of the reactant flow, the hydrogenation reaction is an exothermic reaction, the reaction temperature is gradually increased, and the rear catalyst bed layer is in an environment with less hydrogen in the whole reaction process, and the adoption of the large-aperture low-hydrogen-consumption upflow catalyst is beneficial to the stability of the catalyst bed layer 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. The catalyst of the present invention has complicated inner passage in the high temperature area, and the material oil has long inside stay time and excellent impurity eliminating effect.
3. 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.
4. 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.
5. The residual oil hydrotreating catalyst has relatively large pore volume, pore diameter and pore passage connectivity, and is suitable for the diffusion and conversion of macromolecules such as asphaltene and the like. The initial pressure reduction of the catalyst bed layer is also beneficial to the long-period stable operation of the device.
Drawings
FIG. 1 is a schematic cross-sectional view of a process for preparing a hydroprocessing catalyst carrier A according to the present invention;
FIG. 2 is a schematic view of a guide die of a hydroprocessing catalyst carrier A according to the present invention;
FIG. 3 is a schematic cross-sectional view of a hydroprocessing catalyst support A according to the present invention;
FIG. 4 is a schematic sectional view showing a process for producing a carrier B for a hydroprocessing catalyst according to the present invention;
FIG. 5 is a schematic view of a guide die of a hydroprocessing catalyst carrier B according to the present invention;
FIG. 6 is a schematic sectional view of a hydrotreating catalyst support B of the present invention;
FIG. 7 is a schematic sectional view of a process for preparing a carrier C for a hydroprocessing catalyst according to the present invention;
FIG. 8 is a schematic drawing of a guide die of a hydroprocessing catalyst carrier C according to the present invention;
FIG. 9 is a schematic cross-sectional view of a hydroprocessing catalyst support C according to the present invention;
the reference numerals are explained below:
10. a catalyst support; 100. a pasty material; 20. a mold; 30. guiding a mold; 101. a first channel; 102. a second channel; 103. a third channel; 104. a fourth channel; 105. a fifth channel; 106. a sixth channel; 107. a seventh channel.
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 adopts waterThe pore volumes of the carrier and the contrast carrier are determined by a titration method, the carrier and the contrast carrier are respectively filled in a 100mL measuring cylinder to 100mL scales, then deionized water is added in the measuring cylinder to 100mL scales, the volume of the added water minus the pore volume of the 100mL contrast carrier is the volume among 100mL contrast carrier particles, the volume of the added water minus the pore volume of the 100mL carrier is the volume among 100mL carrier particles and the total volume of each channel, the volume of the carrier and the contrast carrier particles is 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.
The hydrotreating catalyst carrier 10 according to the embodiments of the present invention is generally spherical, as shown in fig. 3, and in the preparation process of the carrier 10, two hemispherical mold assemblies 20 are used to splice a hollow spherical cavity (four or more mold assemblies may be used), and first, a guide mold 30 is placed in the hemispherical mold cavity, as shown in fig. 2. At least three columns or extension lines thereof in the guide mold 30 respectively penetrate through the center of the spherical cavity, and the three columns are perpendicular to each other two by two (refer to fig. 2, which is a schematic view, and a column perpendicular to the paper is not shown), and the paste material 100 is respectively injected into a hemispherical mold where the guide mold 30 is placed and a hemispherical mold without the guide mold, and after the whole cavity is filled, the two hemispherical molds are combined together to form a complete mold 20, refer to fig. 3. The pasty material in the mould is heated to release alkaline gas, so that the pasty material is solidified and contracted and then automatically separated from the mould 20, then the mould is removed by roasting to form a channel of the carrier, and other parts of the spherical cavity in the original mould are completely filled with the solidified material 100, thereby forming the residual oil hydrotreating catalyst carrier 10 in each embodiment.
Catalyst support embodiments
As shown in fig. 3, the catalyst carrier 10 of this embodiment is a spheroid structure formed by solidifying a pasty material 100, and the material 100 has a first tubular channel 101, a second tubular channel 102, a third tubular channel 103, a fourth tubular channel 104 and a fifth tubular channel 105, and the five tubular channels all penetrate through the sphere center of the catalyst carrier 10, so that the five tubular channels are completely communicated, wherein every two of the first channel 101, the second tubular channel 102 and the third tubular channel 103 are perpendicular to each other, and the fourth tubular channel 104 and the fifth tubular channel 105 are arranged in a crossed manner, so that the first, the second, the fourth and the fifth tubular channels are in a shape like a Chinese character mi as a whole, as shown in a section view of the sphere center of fig. 3. The positions of the fourth passages 104 and the fifth passages 105 may be adjusted as appropriate as long as the positions of the passages of the catalyst carrier 10 are ensured to be relatively uniform.
On the basis of fig. 3, the number of channels may be further increased, and the increased channels may penetrate through the center of the catalyst carrier 10 or may be disposed at other positions. As shown in fig. 4 to 6, a sixth passage 106 is provided between the fourth passage 104 and the fifth passage 105, and this sixth passage 106 does not directly penetrate the center of the sphere of the catalyst carrier 10, and it directly penetrates the fourth passage 104 and the fifth passage 105 from head to tail, respectively, and is provided laterally in fig. 6, with a segment thereof directly penetrating the second passage 102, so that the sixth passage 106 added is still in communication with the first to fifth passages. The six channels appear generally in the cross-sectional view of the sphere of fig. 6 as a right-letter-like shape.
Further, as shown in fig. 7 to 9, in addition to the addition of the sixth channel 106, a seventh channel 107 may be added, and the seventh channel 107 and the sixth channel 106 are respectively located on both sides of the center of the sphere of the catalyst carrier 10.
It should be noted that: the three channel solutions of fig. 1-3 can also have many other variations without departing from the design concept, and are not described herein again.
In the present invention, percentages and percentages are by mass unless otherwise specifically indicated.
In the method, the first channel, the second channel, the third channel, the fourth channel and the fifth channel in the bed layer of the high temperature zone and the first channel, the second channel, the third channel, the fourth channel and the fifth channel in the bed layer of the low temperature zone can be the same or different; similarly, in the method of the present invention, the first channel, the second channel, the third channel, the fourth channel, the fifth channel and the sixth channel in the second high temperature zone bed layer may be the same as or different from the first channel, the second channel, the third channel, the fourth channel, the fifth channel and the sixth channel in the high temperature zone bed layer.
The hydrotreating catalyst of the present invention is suitable for use in a low-temperature zone bed, a high-temperature zone bed or a second high-temperature zone bed, unless otherwise specified.
In the present invention, when the hydrotreating catalyst packed in the bed of the low temperature zone and/or the high temperature zone is further defined, the further defined technical characteristics are respectively and independently possessed by the hydrotreating catalyst, but the selection of specific parameters may be the same or different.
In the present invention, the reaction temperature refers to the total average reaction temperature unless otherwise specifically stated.
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
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 1.5, 62.5g of nickel nitrate hexahydrate is added, 390g of alumina sol (with the properties that the Al/Cl ratio is 1.40, the aluminum oxide content is 28 wt%) and gamma-Al are added into the solution after dissolving2O3218.4g (properties are as follows: pore volume is 1.098mL/g, specific surface area is 302m2/g), stirring uniformly, adding 106.7g of hexamethylene tetramine as a curing agent, adding deionized water after the hexamethylene tetramine is completely dissolved, enabling the material in the beaker to be in a paste state with certain fluidity, and enabling the solid content to be 32% in terms of silicon dioxide and aluminum oxide。
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 five cylinders are made of the materials, the length of each cylinder is the diameter of a spherical cavity, and the diameters of the five cylinders are the same. The midpoints of the three cylinders are intersected and perpendicular in pairs, the fourth cylinder is intersected with the midpoint of the fifth cylinder, and any two cylinders of the three cylinders perpendicular in pairs are integrally similar to a Chinese character mi, which is shown in a section view of the center of a sphere in 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 resulting catalyst support A had an outer diameter of about 5.5mm and a channel diameter of about 1.5 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 catalyst ACThe catalyst properties are shown in Table 1.
Example 2
The preparation process is as in example 1, except that on the basis of the guide die of example 1, a cylinder is added, as shown in fig. 4 to 6, namely, a sixth cylinder is arranged between a fourth cylinder and a fifth cylinder, the sixth cylinder does not directly penetrate through the sphere center of the catalyst carrier, the sixth cylinder directly penetrates through the fourth cylinder and the fifth cylinder from head to tail and is transversely arranged in fig. 6, the section of the sixth cylinder directly penetrates through the second cylinder, and the sixth cylinder added in this way is still communicated with the first cylinder to the sixth cylinder. The five cylinders are shown in the cross-sectional view of the center of the sphere of fig. 6 as a whole in a shape resembling a letter. The intersection of the sixth channel with the fourth and fifth channels is located a distance 1/2 from the center of the sphere, which is the radius of the sphere of the carrier.
Prepared catalyst carrier B and catalyst BCThe properties are shown in Table 1. Wherein the obtained catalyst carrier B had an outer diameter of about 5.5mm and a through-hole diameter of about 1.3 mm.
Example 3
The preparation process is as in example 2, except that on the basis of the guide mold of example 2, a cylinder is added, as shown in fig. 7 to 9, that is, a seventh cylinder is added, and the seventh cylinder and the sixth cylinder are symmetrically arranged with respect to the catalyst carrier 10. The distance from the center of the sphere to the intersection of the seventh channel with the fourth and fifth channels is 1/2 the radius of the sphere of the carrier. In addition, the amount of the curing agent hexamethylenetetramine added was changed to 130.2g, and the amount of the water glass added was adjusted to 1428 g.
Prepared catalyst carrier C and catalyst CCThe properties are shown in Table 1. Wherein the obtained catalyst carrier C had an outer diameter of about 5.5mm and a through-hole diameter of about 1.3 mm.
Example 4
Preparation was as in example 1 except that nickel nitrate was not added, catalyst support D and catalyst D were preparedCThe properties are shown in Table 1. Wherein the obtained catalyst carrier D had an outer diameter of about 5.5mm and a through-hole diameter of about 1.5 mm.
Example 5
Pilot test is carried out by adopting an up-flow residual oil hydrogenation reactor device. The upflow reactor is provided with two catalyst beds, wherein, the lower part is a low temperature zone bed and the upper part is a high temperature zone bed.
The raw material is typical middle east residual oil, the low temperature zone bed layer at the middle lower part of the upflow reactor adopts the catalyst A of the inventionCThe bed layer of the upper high-temperature zone adopts the catalyst B of the inventionCThe volume ratio of the catalyst used in the catalyst bed layer of the upper low-temperature zone to the catalyst used in the catalyst bed layer of the lower high-temperature zone is 0.85:1, the total reaction pressure is 16.7MPa at the reaction temperature of 385 ℃, and the liquid hourly space velocity is 0.39h-1Under the process condition of hydrogen-oil specific volume (V/V) 310, carrying out hydrogenation modification reaction in up-flow residual oil hydrogenation reactor to obtain up-flow hydrogenation product after removing impurities of metal and sulfideThe process conditions used to form the oil are shown in Table 3, and the properties of the oil are shown in Table 4.
Example 6
Compared with the example 5, the catalyst A of the invention is adopted in the bed layer of the lower middle-temperature zone of the upflow reactorCThe upper high-temperature zone bed layer adopts the catalyst C of the inventionCThe volume ratio of the catalyst used in the upper catalyst bed layer to the catalyst used in the lower catalyst bed layer is 1:1, the adopted process conditions are as follows: the reaction temperature is 385 ℃, the total reaction pressure is 16.7MPa, and the liquid hourly space velocity is 0.39h-1Hydrogen to oil volume ratio (V/V) 310, resulting in oil properties shown in table 4.
Example 7
Compared with example 5, the upflow reactor was provided with three catalyst beds, wherein the lower part was the low temperature zone bed, the middle part was the high temperature zone bed, and the upper part was the second high temperature zone bed.
The catalyst A is adopted in the bed layer of the low-temperature zone at the middle lower part of the upflow reactorCThe bed layer in the middle high-temperature zone adopts the catalyst BCThe bed layer of the second high-temperature zone at the upper part adopts the catalyst C of the inventionCThe volume ratio of the catalyst used in the upper catalyst bed layer, the middle catalyst bed layer and the lower catalyst bed layer is 1: 1:1, the process conditions used are the same as in example 5, and the resulting oil properties are given in Table 4.
Example 8
Compared with the example 5, the catalyst D of the invention is adopted in the bed layer of the lower middle-temperature zone of the upflow reactorCThe bed layer of the upper high-temperature zone adopts the catalyst B of the inventionCThe volume ratio of the catalyst used in the upper catalyst bed to the catalyst used in the lower catalyst bed was 0.85:1, the process conditions used were the same as in example 5, and the resulting oil properties are shown in Table 4.
Comparative example 1
In comparison with example 5, two catalyst beds were used with the same catalyst A according to the inventionCThe process conditions used are shown in Table 3, and the resulting oil properties are shown in Table 4.
Comparative example 2
In comparison with example 5, two catalyst beds were used with the same catalyst B according to the inventionCWhat is, what isThe process conditions used are shown in Table 3, and the resulting oil properties are shown in Table 4.
Comparative example 3
Compared with the example 5, the same raw materials are adopted to carry out hydrogenation reaction in the upflow reactor under the same process conditions, and the upflow hydrogenation product oil is obtained. The process conditions are detailed in Table 3 and the properties of the oils produced are detailed in Table 4.
The difference from the example 5 is that two beds of the upflow hydrogenation reaction are filled, the lower part is filled with the upflow hydrogenation catalyst FZC10U, and the upper part is filled with the upflow hydrogenation catalyst FZC 11U. FZC10U belongs to a conventional upflow demetallization catalyst and FZC11U belongs to an upflow desulfurization catalyst. The two upflow hydrogenation catalysts were produced by catalyst division, of petrochemical company, ltd. The catalyst properties are shown in Table 2.
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
|
Pore volume, mL/g
|
0.817
|
0.807
|
0.795
|
0.810
|
Specific surface area, m2/g
|
141
|
138
|
140
|
136
|
Average pore diameter, nm
|
23.2
|
23.4
|
22.7
|
23.8
|
Hole distribution,%
|
|
|
|
|
<8.0nm
|
0.7
|
0.6
|
0.8
|
0.6
|
8-16 nm
|
34.1
|
34.9
|
36.4
|
34.3
|
16-100 nm
|
58.4
|
57.2
|
56.5
|
58.4
|
>100.0nm
|
6.8
|
7.3
|
6.3
|
6.7
|
Catalyst numbering
|
AC |
BC |
Cc
|
DC |
Metal content%
|
|
|
|
|
MoO3 |
6.5
|
6.7
|
6.4
|
6.4
|
NiO
|
3.9
|
4.0
|
3.6
|
1.5
|
Lateral pressure strength, N/grain
|
40
|
38
|
46
|
27 |
TABLE 2 Properties of the hydrogenation catalysts used in the comparative examples
Catalyst brand
|
FZC-10U
|
FZC-11U
|
Function(s)
|
Demetallization catalyst
|
Desulfurization catalyst
|
Particle shape
|
Spherical shape
|
Spherical shape
|
Outer diameter of the granule mm
|
2.9
|
2.9
|
Strength, N.mm-1 |
32
|
30
|
Specific surface area, m2/g
|
110
|
148
|
Wear rate, wt%
|
0.3
|
0.4
|
Metal content, wt.%
|
|
|
MoO3 |
5.2
|
10.8
|
NiO
|
1.2
|
2.4 |
TABLE 3 Main operating conditions adopted for examples 5, 7 and comparative examples 1-3
Item
|
Example 5
|
Example 7
|
Comparative example 1
|
Comparative example 2
|
Comparative example 3
|
Catalyst numbering
|
Catalyst ACAnd a catalyst
BC |
Catalyst ACAnd catalyst BCAnd catalysis
Agent CC |
Catalyst and process for preparing same
AC |
Catalyst and process for preparing same
BC |
FZC-10U and FZC-
11U
|
Total reaction pressure, MPa
|
16.7
|
16.7
|
16.7
|
16.7
|
16.7
|
The liquid hourly volume space velocity is controlled,
h-1 |
0.39
|
0.39
|
0.39
|
0.39
|
0.39
|
inlet gas-oil ratio
|
310
|
310
|
310
|
310
|
310
|
Reaction temperature of
|
384.5
|
385.5
|
385
|
385
|
385.5 |
Table 4 raw materials and evaluation results of examples 5 to 8 of the present invention
Item
|
Raw materials
|
Example 5
|
Example 6
|
Example 7
|
Example 8
|
Catalyst numbering
|
|
Catalysts Ac and Bc
|
Catalysts Ac and Cc
|
Catalysts Ac, Bc and Cc
|
Catalysts Dc and Bc
|
Density (20 ℃), kg/m3 |
977.2
|
952.5
|
953.3
|
953.2
|
953.6
|
S,wt%
|
2.95
|
1.03
|
1.06
|
1.02
|
1.19
|
N,μg/g
|
3258
|
2230
|
2250
|
2332
|
2467
|
Carbon Residue (CCR), wt%
|
10.9
|
6.73
|
6.11
|
6.32
|
7.87
|
Viscosity (100 ℃ C.), mm2/s
|
95.3
|
38.2
|
37.35
|
36.32
|
39.65
|
Ni+V,µg/g
|
64.2
|
23.50
|
23.54
|
22.12
|
25.55 |
TABLE 4 evaluation results of (subsequent) raw materials and comparative examples 1 to 3
Item
|
Raw materials
|
Comparative example 1
|
Comparative example 2
|
Comparative example 3
|
Catalyst numbering
|
|
Catalyst Ac
|
Catalyst Bc
|
FZC-10U and FZC-11U
|
Density (20 ℃), kg/m3 |
977.2
|
955.0
|
955.3
|
955.3
|
S,wt%
|
2.95
|
1.37
|
1.42
|
1.55
|
N,μg/g
|
3258
|
2682
|
2735
|
2746
|
Carbon Residue (CCR), wt%
|
10.9
|
7.96
|
8.20
|
8.83
|
Viscosity (100 ℃ C.), mm2/s
|
95.3
|
42.50
|
42.61
|
42.20
|
Ni+V,µg/g
|
64.2
|
27.81
|
28.88
|
30.03 |
Example 9
In order to further examine the influence of the activity and stability of the upflow catalyst and the process technology, the stability test of the catalyst is carried out in example 5, the reaction temperature is 385 ℃, the total reaction pressure is 16.7MPa, and the liquid hourly volume space velocity is 0.39h-1And carrying out hydro-upgrading reaction in the upflow residual oil hydrogenation reactor under the process condition of hydrogen-oil specific volume (V/V) 310, wherein the reaction result is shown in Table 5.
Comparative example 4
In order to further examine the influence of the activity and stability of the upflow catalyst and the process technology, the stability test of the catalyst is carried out on the comparative example 1, the reaction temperature is 385 ℃, the total reaction pressure is 16.7MPa, and the liquid hourly volume space velocity is 0.39h-1And carrying out hydro-upgrading reaction in the upflow residual oil hydrogenation reactor under the process condition of hydrogen-oil specific volume (V/V) 310, wherein the reaction result is shown in Table 5.
Comparative example 5
In order to further examine the inventionThe influence of the activity and stability of the upflow catalyst and the process technology is shown, the stability test of the catalyst is carried out on the comparative example 3, the reaction temperature is 385 ℃, the total reaction pressure is 16.7MPa, and the liquid hourly volume space velocity is 0.39h-1And carrying out hydro-upgrading reaction in the upflow residual oil hydrogenation reactor under the process condition of hydrogen-oil specific volume (V/V) 310, wherein the reaction result is shown in Table 5.
TABLE 5 residual oil hydrogenation stability test
Fixed bed reactor
|
|
500h
|
1000h
|
2000h
|
3000h
|
Temperature rise of one bed layer, deg.C
|
Example 9
|
16
|
16
|
15
|
15
|
Temperature rise of one bed layer, deg.C
|
Comparative example 4
|
14
|
13
|
12
|
10
|
Temperature rise of one bed layer, deg.C
|
Comparative example 5
|
14
|
12
|
12
|
10
|
Temperature rise of the second bed layer and DEG C
|
Example 9
|
14
|
14
|
13
|
12
|
Temperature rise of the second bed layer and DEG C
|
Comparative example 4
|
12
|
11
|
11
|
10
|
Temperature rise of the second bed layer and DEG C
|
Comparative example 5
|
14
|
13
|
12
|
12
|
Total temperature rise, deg.C
|
Example 9
|
30
|
30
|
28
|
27
|
Total temperature rise, deg.C
|
Comparative example 4
|
28
|
26
|
24
|
20
|
Total temperature rise, deg.C
|
Comparative example 5
|
28
|
25
|
24
|
22
|
Product oil S, wt%
|
Example 9
|
1.03
|
1.04
|
1.09
|
1.10
|
Product oil S, wt%
|
Comparative example 4
|
1.37
|
1.39
|
1.48
|
1.56
|
Product oil S, wt%
|
Comparative example 5
|
1.54
|
1.58
|
1.66
|
1.73
|
Resulting oil CCR, wt%
|
Example 9
|
6.73
|
6.79
|
6.83
|
6.88
|
Resulting oil CCR, wt%
|
Comparative example 4
|
7.96
|
8.22
|
8.36
|
8.95
|
Resulting oil CCR, wt%
|
Comparative example 5
|
8.83
|
8.95
|
9.22
|
9.37
|
Generating oil Ni + V, mug/g
|
Example 9
|
23.55
|
23.68
|
24.15
|
24.66
|
Generating oil Ni + V, mug/g
|
Comparative example 4
|
27.83
|
28.86
|
29.94
|
30.30
|
Generating oil Ni + V, mug/g
|
Comparative example5
|
30.20
|
31.22
|
32.61
|
34.85 |
From the examination of the long run length of Table 5, it can be seen that in the upflow reactor, the reaction temperature is 385 ℃, the total reaction pressure is 16.7MPa, and the liquid hourly space velocity is 0.39h-1In the process condition of hydrogen-oil specific volume (V/V) 310, the catalyst bed in example 9 obtained a better reaction effect by using the catalysts with different shapes of the present invention to perform the reaction, and after 3000 hours of stable operation, the obtained hydrogenated oil has the following properties: the sulfur content is 1.10%, the carbon residue is less than 7%, and the metal content is less than 25 mug/g. The property of the produced oil obtained by adopting the catalyst of the invention is obviously improved compared with the property of the produced oil obtained by adopting the existing catalyst in the comparative example, and the catalyst of the invention has better hydrogenation activity and stability compared with the catalyst in the comparative example.
In addition, as can be seen from table 5, the process technology of the present invention can effectively improve the temperature rise of each catalyst bed layer of the upflow reactor, which is important for the performance of the catalyst, and can improve the reaction environment of the reactor, and improve the hydrogenation activity and stability of the whole catalyst system, thereby prolonging the service life of the catalyst.