Method for treating 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 treating heavy hydrocarbon raw material 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, catalysts with different activities are filled in different beds, so that backmixing of the catalysts and instability of the beds are easily caused, the activity of the catalysts in the upflow reactor is gradually increased along the material flow direction, the hydrogen consumption of the high-activity catalyst beds is gradually increased, the heat release is increased, the local hydrogen deficiency of the catalyst beds and disturbance of the beds are easily caused due to the limitation of the hydrogen-oil ratio of the upflow reactor, hot spots are easily generated, and the performance of the catalysts and the stable operation of the device are influenced.
Disclosure of Invention
In view of the deficiencies of the prior art, the present invention provides a process for treating a heavy hydrocarbon feedstock using an upflow hydrogenation reactor. The method adopts a specific catalyst and an up-flow hydrogenation process technology to treat the heavy hydrocarbon raw material, and the catalyst has good hydrogenation performance and capacity of removing metal, simultaneously has certain capacities of desulfurizing, carbon residue and asphaltene conversion, and has high hydrogenation activity and long service life. In addition, the single-variety catalyst is applied to the upflow reactor, and the problems of multiple catalyst types, complicated loading and unloading, back mixing of different catalysts and the like in the conventional upflow reactor are solved.
The invention provides a method for treating a heavy hydrocarbon raw material by adopting an up-flow hydrogenation reactor, which comprises the steps of adopting at least one up-flow hydrogenation reactor, wherein at least two catalyst beds are arranged in the up-flow hydrogenation reactor, and each catalyst bed adopts the same hydrogenation treatment catalyst; the hydrotreating catalyst comprises a carrier and an active metal component, wherein the carrier is spherical with two through channels, the outer diameter of the ball is 5.0-8.0 mm, the two channels pass through the center of the ball and are mutually perpendicular through holes, and the diameter of the through holes is 30-60% of the outer diameter of the ball, and is preferably 30-55%.
In the hydrotreating catalyst of the invention, the through-hole may preferably be a cylindrical through-hole.
In the hydrotreating catalyst of the invention, the active metal component includes a second metal component, i.e., a VIB group metal element, and a third metal component, i.e., a VIII group metal element.
In the hydrotreating catalyst of the invention, Al is used2O3-SiO2As a carrier, wherein SiO2The weight content is 35-80%, preferably 40-60%.
In the hydrotreating catalyst of the invention, the VIB group metal element as the active metal component is preferably Mo, and the VIII group metal element is preferably Ni and/or Co. Wherein, the content of the second metal calculated by oxide is 1.0-10.0%, preferably 1.5-6.5%, the total content of the first metal component and the third metal component calculated by oxide is 3.0-10.0%, preferably 4.0-8.0%, the content of silicon oxide is 35.0-55.0%, the content of aluminum oxide is 35.0-55.0%, the molar ratio of the third metal component to the second metal component calculated by atom is 1.5: 1-4.5: 1.
in the hydrotreating catalyst of the present invention, the support 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 invention has the following properties: the specific surface area is 80-200 m2The pore volume is more than 0.80mL/g, preferably 0.85-1.15 mL/g, the pore volume occupied by the pore diameter of 20-100 nm is 35-60% of the total pore volume, and the average pore diameter is more than 18nm, preferably 20-30 nm.
The preparation method of the hydrotreating catalyst comprises the following steps:
(1) adding an acidic peptizing agent into a silicon source for acidification treatment;
(2) adding pseudo-boehmite and a curing agent into the step (1) to prepare a 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) removing the material in the step (3) from the mold, washing, drying and roasting to obtain a catalyst carrier;
(5) 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 hydrotreating catalyst.
In the preparation method of the hydrotreating catalyst according to 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 dry weight of the pseudo-boehmite in the step (2) is more than 70 percent, and the pseudo-boehmite is converted into gamma-Al by high-temperature roasting2O3The latter properties are as follows: 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(ii) in terms of/g. The curing agent is one or more of urea and organic ammonium salt, and the organic ammonium salt is preferably hexamethylenetetramine. The addition amount of the curing agent is that the molar ratio of nitrogen atoms to silicon dioxide is 1: 1.5-1: 2.0. 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 three mandrels, wherein the shell is made of rigid materials, the external shape of the shell can be any shape, preferably a spherical geometric shape with equal symmetry, and one of the three mandrels is a long mandrel with the length larger than the diameter of the spherical cavity and two short mandrels with the length larger than the radius of the spherical cavity. The invention is explained by taking the spherical shape as an example, the spherical shell is respectively provided with four threaded through holes, wherein every two of the threaded through holes are symmetrically distributed by taking the spherical center of the cavity as a symmetric center, and 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 spherical shell can be composed of two identical hemispheres or four quarter spheres. The long mandrel is arranged in a through hole of the spherical shell and penetrates through the spherical cavity, the diameter of the mandrel can be adjusted according to the aperture size of two through channels in the catalyst, the diameter of the mandrel can be 30% -60% of the diameter of the spherical cavity, preferably 30% -55%, threads are arranged at two ends of the mandrel, the size of the threads is matched with the threads in the through hole of the shell, the long mandrel is fixedly arranged to enable each spherical shell to form a sphere, the spherical cavity is formed inside the spherical cavity, the other two short mandrels are respectively inserted into the other two thread through holes and contact with the long mandrel and then are fixed, and the diameter of the other two short mandrels is the. During preparation, the long core shaft is inserted into the two through holes on the shell to fix the spherical shells of the two parts, the inner parts of the spherical shells form a complete cavity sphere, then the other short core shaft is inserted into the through hole of the shell to be fixed after contacting with the long core shaft, the last through hole of the shell is kept smooth, at the moment, the pasty material is injected or pressed into the through hole of the shell to fill the whole cavity, the last short core shaft is inserted into the through hole of the shell to be fixed after contacting with the long core shaft. Three vertically fixed mandrels will form mutually perpendicular carrier channels. And heating the paste material containing mould 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), the pasty material is heated in the die and releases alkaline gas, so that the pasty material is cured and contracted and then is automatically demoulded; the washing 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, 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 treating residual oil by using an up-flow hydrogenation reactor, at least one up-flow hydrogenation reactor is adopted, and one or two up-flow hydrogenation reactors are generally adopted as the up-flow hydrogenation reactor.
The upflow hydrogenation reactor is preferably provided with 2-5 catalyst beds, 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 the upflow hydrogenation 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 type hydrogenation 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 type hydrogenation reactor, the second bed accounts for 25-35% of the total filling volume of the catalyst in the upflow type hydrogenation reactor, and the third bed accounts for 30-45% of the total filling volume of the catalyst in the upflow type hydrogenation reactor. The catalyst bed height may be set the same or different depending on the process feedstock.
In the method for treating the heavy hydrocarbon raw material by using the up-flow hydrogenation reactor, the operation conditions adopted by the up-flow hydrogenation reactor are as follows: 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.
Compared with the prior art, the invention has the advantages that:
1. the upflow type hydrotreating reactor is filled with at least two catalyst beds and the same hydrotreating catalyst, and the hydrotreating catalyst with unique appearance and pore structure provided by the invention not only has higher mechanical strength and wear resistance, but also has the following characteristics: (1) the device has good diffusion channels and reaction channels, can eliminate the influence of diffusion on the reaction, enables the reaction to be more efficient, and has better utilization effect of the catalyst; (2) the anti-coking and bed thermal stability are good; (3) the catalyst has good hydrogenation performance; (4) has good capacity of removing metal impurities and certain capacity of removing sulfur nitrogen and carbon residue impurities.
2. By adopting the method of the invention, at least two catalyst beds are filled in the upflow hydrogenation reactor and the same hydrotreating catalyst is filled, because the material property is gradually improved along the direction of the 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.
3. In the upflow hydrogenation reactor, although not as strongly backmixed 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.
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 cross-sectional view of a hydroprocessing catalyst support according to the present invention;
the reference numerals are explained below:
1. a mold housing; 2. a pasty material; 3. a long mandrel; 4. a short mandrel; 5. a through passage.
Detailed Description
The technical solution of the present invention is further described in detail with reference to the following examples, which are not intended to limit the scope of the present invention. In the present invention, wt% is a mass fraction.
In the invention, the specific surface area, the pore volume, the pore diameter and the pore distribution are measured by adopting a low-temperature liquid nitrogen adsorption method.
As shown in fig. 1, when preparing a residual oil hydrotreating catalyst carrier according to the present invention, the mold comprises a mold housing 1 having a spherical cavity, a long mandrel 3, and two short mandrels 4. The present invention will be described by taking an example in which the outer shape is spherical. Four threaded through holes are respectively arranged on the spherical mould shell 1, wherein every two of the threaded through holes are symmetrically distributed by taking the spherical center of the cavity as a symmetric center, and the diameter of the spherical cavity is D1. The spherical mould shell 1 consists of two identical hemispheres. The long mandrel 3 is arranged in the through hole of the spherical mould shell 1 and penetrates through the spherical cavity, and the diameter of the long mandrel 3 is d1The length of the long mandrel 3 is larger than the diameter of the spherical cavity, threads are arranged at two ends of the mandrel, the thread size is matched with threads in the through hole of the shell, the long mandrel 3 is installed and fixed to enable the two hemispherical spherical mould shells 1 to form the spherical cavity inside, the other two short mandrels 4 are respectively inserted into the through holes of the other two threads, the diameter of the mandrel is the same as that of the long mandrel 3, the length of the short mandrel 4 is larger than the radius of the spherical cavity, and when the short mandrel 4 contacts the long mandrel 3, the short mandrel is fixed.
When preparing a residual oil hydrotreating catalyst, a long mandrel 3 is inserted into a threaded through hole on a spherical mold shell 1 and penetrates through the interior of a spherical cavity, the long mandrel 3 is installed and fixed to enable the two hemispherical spherical mold shells 1 to form the spherical cavity inside, then another short mandrel 4 is inserted into one through hole of the shell and fixed after contacting the long mandrel 3, the last through hole of the shell is kept smooth, at the moment, a paste material 2 is pressed into the last through hole of the spherical mold shell 1 to fill the whole cavity, the last short mandrel 4 is inserted into the shell and fixed after contacting the long mandrel 3. Three vertically fixed mandrels will form mutually perpendicular through channels 5, fig. 2.
Example 1
1000g of water glass with the silicon oxide content of 30 wt% is weighed and added into a beaker, a stirring device is started, 376g of nitric acid solution with the mass concentration of 62% is slowly added into the beaker, the pH value of the water glass solution in the beaker is enabled to be 2.0, and 416.7g of pseudo-boehmite (with the properties as follows: the pore volume is 0.985mL/g, the specific surface area is 313 m)272 percent of dry basis), adding 83g of curing agent urea after stirring uniformly, adding deionized water after the urea is completely dissolved, and enabling the material in the beaker to be in a paste shape with certain fluidity, wherein the solid content is 33 percent calculated by silicon dioxide and aluminum oxide.
Pressing the paste material into a rigid body mold which is prepared in advance and is provided with a spherical cavity and a mandrel, after the paste material is filled in the whole cavity, inserting the last short mandrel, and fixing the short mandrel after the short mandrel contacts the first mandrel. Two vertically fixed mandrels will form mutually perpendicular carrier channels.
Heating a mould containing the paste material to 120 ℃, keeping the temperature for 60 minutes, releasing ammonia gas after the paste material in the mould 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 600 ℃ to obtain the spherical catalyst carrier A, wherein the outer diameter of the obtained catalyst carrier A is about 5.5mm, and the diameter of a through hole is about 2.5 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 the mold is changed, the diameters of the cavity and the mandrel are increased, and the prepared catalyst carrier B and the prepared catalyst BCThe properties are shown in Table 1. Wherein the obtained catalyst carrier B had an outer diameter of about 7.5mm and a through-hole diameter of about 3.8 mm.
Example 3
The procedure was as in example 1, except that 373g and 53g of a 62% by mass nitric acid solution and 35% by mass solid content in terms of silica and alumina were slowly added to a beaker, and catalyst carrier C and catalyst C were preparedCThe 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 2.5 mm.
Comparative example 1
Weighing 1000g of water glass with the silicon oxide content of 30 percent, adding the water glass into a beaker, starting a stirring device, slowly adding 376g of nitric acid solution with the concentration of 62 percent into the beaker to ensure that the pH value of the water glass solution in the beaker is 2.0, and adding 0.985mL/g of pore volume and 313m of specific surface area into the solution2416.7g of pseudo-boehmite with a dry basis of 72 percent, adding 83g of curing agent urea after uniformly stirring, adding deionized water after the urea is completely dissolved, and enabling the material in the beaker to be in a paste with certain fluidity, wherein the sum concentration of the silicon dioxide and the aluminum oxide is 33 percent.
Pressing the paste material into two hemispherical hollow structural rigid body molds with the same diameter, and extruding the two hemispherical molds into a sphere;
heating a mould containing the paste material to 120 ℃, keeping the temperature for 60 minutes, releasing ammonia gas after the paste material in the mould 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 600 ℃ to obtain the spherical catalyst carrier D of the comparative example, wherein the outer diameter of the obtained catalyst carrier D is about 5.5 mm.
The carrier D was impregnated with a Mo-Ni-P solution, dried at 120 ℃ for 6 hours, and calcined at 500 ℃ for 3 hours to obtain the catalyst D of this comparative exampleCThe catalyst properties are shown in Table 1.
Example 4
Pilot test is carried out by adopting an up-flow residual oil hydrogenation reactor device. The upflow reactor was set up with two catalyst beds.
The raw material is typical middle east residual oil, two catalyst beds in an upflow reactor adopt the same catalyst A 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 0.9:1, the total reaction pressure is 15.7MPa within the range of 385-386 ℃ of the total average reaction temperature, and the liquid hourly space velocity is 0.42h-1Under the process condition of hydrogen-oil specific volume (V/V)270, hydrogenation modification reaction is carried out in an upflow residual oil hydrogenation reactor, impurities such as metal, sulfide and the like are mainly removed, upflow hydrogenation product oil is obtained, and the properties of the product oil are shown in Table 4.
Example 5
In comparison with example 4, two catalyst beds were used with catalyst BCThe volume ratio of the catalyst used in the upper catalyst bed layer to the catalyst used in the lower catalyst bed layer is 1:1.2, and the adopted process conditions are as follows: in the range of the total average reaction temperature of 380 ℃, the total reaction pressure is 16.0MPa, and the liquid hourly volume space velocity is 0.55h-1The properties of the resulting oil under the process conditions of hydrogen to oil volume ratio (V/V)270 are shown in Table 4.
Example 6
In comparison with example 4, two catalyst beds were used with catalyst CCThe volume ratio of the catalyst used in the upper catalyst bed to the catalyst used in the lower catalyst bed was 1:1.5, the process conditions used are shown in Table 3, and the oil formation properties are shown in Table 4.
Comparative example 2
In comparison with example 6, two catalyst beds were used with catalyst DCThe 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 6, 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 6 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. Two upflow hydrogenation catalysts were produced by catalyst division, of petrochemical company, ltd, china, and the catalyst properties are shown in table 2.
TABLE 1 Properties of catalyst supports and catalysts prepared in examples and comparative examples
Catalyst support numbering
|
Carrier A
|
Carrier B
|
Carrier C
|
Carrier D
|
Pore volume, mL/g
|
0.771
|
0.772
|
0.769
|
0.760
|
Specific surface area, m2/g
|
140
|
142
|
137
|
151
|
Average pore diameter, nm
|
22.1
|
21.8
|
22.5
|
20.1
|
Hole distribution,%
|
|
|
|
|
<8.0nm
|
0.8
|
0.9
|
0.9
|
1.2
|
8-20nm
|
62.4
|
62.4
|
62.4
|
63.6
|
>20.0nm
|
36.8
|
36.7
|
36.7
|
35.2
|
Catalyst numbering
|
Catalyst AC |
Catalyst BC |
Catalyst CC |
Catalyst DC |
Metal content%
|
|
|
|
|
MoO3 |
8.5
|
8.3
|
8.4
|
8.6
|
NiO
|
2.1
|
2.2
|
4.1
|
2.1
|
Lateral pressure strength, N/grain
|
31
|
45
|
40
|
87 |
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 used in example 6 and comparative examples 2-3
Table 4 raw materials and evaluation results of inventive examples 4 to 6 and comparative examples 2 to 3
Example 7
To further examine the influence of the activity and stability of the upflow catalyst and process of the present invention, catalyst stability test was conducted on example 6, and the inlet conditions of the upflow reactor in the comparative test were identical to those in comparative example 4, and the reaction results are shown in Table 5.
Comparative example 4
To further examine the influence of the activity and stability of the upflow catalyst and process of the present invention, comparative example 3 was subjected to a catalyst stability test in which the inlet conditions of the upflow reactor were the same as in example 7 and the reaction results are 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 7
|
16
|
16
|
15
|
15
|
Temperature rise of one bed layer, deg.C
|
Comparative example 4
|
12
|
11
|
11
|
10
|
Temperature rise of the second bed layer and DEG C
|
Example 7
|
12
|
12
|
11
|
11
|
Temperature rise of the second bed layer and DEG C
|
Comparative example 4
|
17
|
14
|
13
|
12
|
Total temperature rise, deg.C
|
Example 7
|
28
|
28
|
26
|
26
|
Total temperature rise, deg.C
|
Comparative example 4
|
29
|
25
|
24
|
22
|
Product oil S, wt%
|
Example 7
|
1.34
|
1.36
|
1.38
|
1.40
|
Product oil S, wt%
|
Comparative example 4
|
1.43
|
1.49
|
1.60
|
1.65
|
Resulting oil CCR, wt%
|
Example 7
|
8.13
|
8.15
|
8.16
|
8.18
|
Resulting oil CCR, wt%
|
Comparative example 4
|
8.48
|
8.52
|
8.58
|
8.62
|
Oil production Ni + V,. mu.g/g
|
Example 7
|
39.4
|
40.6
|
41.5
|
41.8
|
Oil production Ni + V,. mu.g/g
|
Comparative example 4
|
47.6
|
48.5
|
48.8
|
50.2 |
From the examination of the long run length of Table 5, it can be seen that the properties of the product oil obtained by the reaction using the catalyst of the present invention are significantly improved as compared with the product oil obtained by the reaction using the conventional catalyst in the comparative example, and the catalyst of the present invention has better hydrogenation activity and stability as 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.