A method for hydrotreating residual oil

Abstract

The present invention relates to the field of hydroprocessing technology, and specifically discloses a method for hydroprocessing residual oil, comprising: (1) introducing a wax oil feedstock into a first hydrogenation reaction zone containing a wax oil hydrogenation catalyst in the presence of hydrogen to perform a first hydrogenation reaction to obtain hydrogenated wax oil; (2) introducing a mixed flow containing vacuum residue oil and the hydrogenated wax oil into a second hydrogenation reaction zone in the presence of hydrogen to perform a second hydrogenation reaction to obtain hydrogenated residual oil; the second hydrogenation reaction zone is sequentially filled with a hydrogenation protection catalyst, a hydrodemetallization catalyst, and a hydrodesulfurization and decarbonization catalyst according to the flow direction of the liquid phase stream. The method adopts a zoned hydroprocessing and heat exchange treatment method, and improves the vacuum residue oil ratio, the residue oil denitrogenation rate, the desulfurization rate, the decarbonization rate, the demetallization rate, and the hydrogen content of the hydroprocessed residual oil compared to the existing process, and reduces the energy consumption level of the device and improves the operational stability.

Description

Technical Field

[0001] The present invention relates to the field of hydroprocessing technology, and in particular to a method for hydroprocessing residual oil. Background Art

[0002] Residue hydrotreating-catalytic cracking (RHT-RFCC) combined technology is one of the most effective residue conversion technologies. Residue hydrotreating-catalytic cracking produces high-quality, light products with high yields. This efficient conversion and utilization of residue also delivers significant economic benefits to refineries.

[0003] However, nitrogen compounds in residual oil, especially basic nitrogen compounds, preferentially adsorb on the acidic sites of the catalyst during catalytic cracking, reducing the density of acidic sites, thereby lowering catalytic cracking conversion and affecting reaction selectivity. This effect is more pronounced with higher nitrogen compound content in the residual oil. However, the denitrification rate of residual oil hydrotreating units currently only reaches 40% to 55%. Therefore, improving the denitrification rate of residual oil hydrotreating units would be beneficial to improving refinery profitability.

[0004] The wax components in residual oil have very low hydrogenation efficiency and low denitrification rates in residual oil hydrotreating units. This is partly due to the much lower intrinsic activity of residual oil hydrotreating catalysts than that of wax oil hydrotreating catalysts. Furthermore, residual oil contains a large amount of asphaltene and colloidal macromolecules, which have a much higher adsorption capacity on the catalyst than wax oil molecules, making it difficult for wax oil molecules to reach the catalyst for an effective reaction.

[0005] CN101747935A discloses a method for producing light olefins and monocyclic aromatic hydrocarbons from heavy hydrocarbons. A wax oil feedstock, catalytic cracking light cycle oil, and / or catalytic cracking heavy cycle oil are contacted with a wax oil hydrogenation catalyst in a first hydrogenation reaction zone. The reaction effluent is mixed with residual oil and then sequentially passed through a second hydrogenation reaction zone filled with a residual oil hydrogenation catalyst. This method enables zoned hydrogenation of wax oil and residual oil. However, due to limitations in operating conditions, energy consumption, and cost, the amount of vacuum residue incorporated is relatively low, making it unsuitable for the combined residual oil hydrotreating-catalytic cracking (RHT-RFCC) technology using residual oil as a feedstock.

[0006] CN105524655A and CN105586082A disclose a heavy oil hydrodenitrogenation method. This method involves stripping the stream before the denitrification catalyst to increase hydrogen purity. Simultaneously, sulfur-containing substances are added to the stream to increase the hydrogen sulfide content in the atmosphere over the denitrification catalyst bed, thereby improving the overall denitrification rate. However, the process is relatively complex and difficult to implement in industrial settings. Summary of the Invention

[0007] The purpose of the present invention is to overcome the problems existing in the prior art, namely, to overcome the problems of low hydrogenation efficiency of the residue oil hydrogenation catalyst and high energy consumption of the device in the prior art.

[0008] In order to achieve the above object, the present invention provides a method for hydrotreating residual oil, which is carried out in a fixed-bed hydrogenation device containing a first hydrogenation reaction zone and a second hydrogenation reaction zone, comprising:

[0009] (1) In the presence of hydrogen, introducing a wax oil feedstock into a first hydrogenation reaction zone containing a wax oil hydrogenation catalyst to perform a first hydrogenation reaction to obtain a hydrogenated wax oil;

[0010] (2) In the presence of hydrogen, introducing a mixed flow containing vacuum residue oil and the hydrogenated wax oil into a second hydrogenation reaction zone for a second hydrogenation reaction to obtain hydrogenated residue oil; the second hydrogenation reaction zone is sequentially filled with a hydrogenation protection catalyst, a hydrodemetallization catalyst, and a hydrodesulfurization and carbon residue removal catalyst according to the flow direction of the liquid phase stream;

[0011] Optionally, the mixed stream further contains catalytically cracked light cycle oil;

[0012] Based on the total mass flow of the wax oil feedstock, the vacuum residue oil, and the catalytic cracking light cycle oil entering the hydrogenation unit, the mass flow of the wax oil feedstock entering the hydrogenation unit is 20-65%, the mass flow of the catalytic cracking light cycle oil entering the hydrogenation unit is 0-30%, and the mass flow of the vacuum residue oil entering the hydrogenation unit is 35-80%.

[0013] The method for residual oil zone hydrotreatment provided by the present invention can remove almost all nitrogen-containing compounds in wax oil, thereby effectively improving the denitrogenation rate of residual oil hydrogenation, and the hydrogen content, desulfurization rate, residual carbon removal rate and demetallization rate are also improved to varying degrees, providing high-quality raw materials for downstream catalytic cracking units, thereby saving production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Only key equipment is marked in the figure, and equipment known to those skilled in the art, such as pumps, heat exchangers, separators, etc., are omitted. Those skilled in the art should not understand this as a limitation to the present invention.

[0015] Figure 1 It is a schematic flow diagram of the method for residual oil zone hydrotreating of the present invention.

[0016] Description of Reference Numerals

[0017] F101 Heating furnace 1 Vacuum residue oil

[0018] R101 First hydrogenation reaction zone 2 circulating hydrogen

[0019] R102 Second Hydrogenation Reaction Zone 3 Catalytic Cracking Light Cycle Oil

[0020] E101 Hydrogenated Residue Oil-Hydrogen Mixed Light Circulating Oil Heat Exchanger 4 Wax Oil Raw Material

[0021] E102 Hydrogenated Residue Oil-Hydrogenated Wax Oil Heat Exchanger 5 New Hydrogen DETAILED DESCRIPTION

[0022] The endpoints of the ranges and any values disclosed herein are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0023] As mentioned above, the present invention provides a method for hydrotreating residual oil, which is carried out in a fixed-bed hydrogenation unit comprising a first hydrogenation reaction zone and a second hydrogenation reaction zone, comprising:

[0024] (1) In the presence of hydrogen, introducing a wax oil feedstock into a first hydrogenation reaction zone containing a wax oil hydrogenation catalyst to perform a first hydrogenation reaction to obtain a hydrogenated wax oil;

[0025] (2) In the presence of hydrogen, introducing a mixed flow containing vacuum residue oil and the hydrogenated wax oil into a second hydrogenation reaction zone for a second hydrogenation reaction to obtain hydrogenated residue oil; the second hydrogenation reaction zone is sequentially filled with a hydrogenation protection catalyst, a hydrodemetallization catalyst, and a hydrodesulfurization and carbon residue removal catalyst according to the flow direction of the liquid phase stream;

[0026] Optionally, the mixed stream further contains catalytically cracked light cycle oil;

[0027] Based on the total mass flow of the wax oil feedstock, the vacuum residue oil, and the catalytic cracking light cycle oil entering the hydrogenation unit, the mass flow of the wax oil feedstock entering the hydrogenation unit is 20-65%, the mass flow of the catalytic cracking light cycle oil entering the hydrogenation unit is 0-30%, and the mass flow of the vacuum residue oil entering the hydrogenation unit is 35-80%.

[0028] The inventors have discovered that the method provided by the present invention can effectively improve the denitrification rate, hydrogen content, desulfurization rate, carbon residue removal rate, and metal removal rate of residual oil hydrogenation. Preferably, the addition of catalytic cracking light cycle oil can reduce the viscosity of the vacuum residue, thereby further facilitating the hydrogenation reaction.

[0029] Preferably, in step (1), 1-2 fixed bed reactors are provided in the first hydrogenation reaction zone.

[0030] Preferably, in step (2), 2-5 fixed bed reactors are provided in the second hydrogenation reaction zone.

[0031] Preferably, in the present invention, the reactors in the first hydrogenation reaction zone and the second hydrogenation reaction zone are each independently connected in series.

[0032] In addition, it should be noted that the present invention has no special requirements for the loading method of the catalyst in the fixed bed reactor in the second hydrogenation reaction zone. Various types of catalysts can be loaded into the same fixed bed reactor in the order required by the present invention, or they can be loaded separately into multiple fixed bed reactors, as long as the loading order of the catalysts is in accordance with the requirements of the present invention.

[0033] Preferably, in step (1), the conditions of the first hydrogenation reaction at least meet the following requirements: temperature of 320-430°C, reaction pressure of 6-20 MPa, liquid hourly space velocity of 0.3-2.0 h -1 , the hydrogen-oil volume ratio is 250-1500:1. More preferably, in step (1), the conditions of the first hydrogenation reaction at least meet the following requirements: temperature of 350-410°C, reaction pressure of 10-18 MPa, liquid hourly space velocity of 0.6-1.5h -1 , the volume ratio of hydrogen to oil is 300-1000:1.

[0034] Preferably, in step (1), the asphaltene content in the wax oil feedstock is less than or equal to 500 ppm. More preferably, the wax oil feedstock is selected from at least one of conventional third-tier oil, conventional fourth-tier oil, top-cut oil, first-tier oil, second-tier oil, third-tier oil, fourth-tier oil, coker wax oil, deasphalted oil, and catalytic cracking heavy cycle oil.

[0035] Preferably, in step (2), the conditions of the second hydrogenation reaction at least meet the following requirements: temperature of 330-450°C, reaction pressure of 6-25 MPa, liquid hourly space velocity of 0.1-1 h -1 , the hydrogen-oil volume ratio is 250-1500:1. More preferably, in step (2), the conditions of the second hydrogenation reaction at least meet the following requirements: temperature of 360-430°C, reaction pressure of 12-20 MPa, liquid hourly space velocity of 0.1-0.4h -1 , the volume ratio of hydrogen to oil is 300-1000:1.

[0036] Preferably, based on the total mass flow rate of the wax oil feedstock, the vacuum residue oil, and the catalytic cracking light cycle oil entering the hydrogenation unit, the mass flow rate of the wax oil feedstock entering the hydrogenation unit is 25-50%, the mass flow rate of the catalytic cracking light cycle oil entering the hydrogenation unit is 0-20%, and the mass flow rate of the vacuum residue oil entering the hydrogenation unit is 50-75%.

[0037] According to a preferred embodiment, based on the total volume of the catalysts loaded in the hydrogenation unit, the loading volume ratio of the wax oil hydrogenation catalyst is 2-25%, the loading volume ratio of the hydrogenation protection catalyst is 1-20%, the loading volume ratio of the hydrodemetallization catalyst is 10-60%, and the loading volume ratio of the hydrodesulfurization and carbon residue removal catalyst is 30-80%. More preferably, based on the total volume of the catalysts loaded in the hydrogenation unit, the loading volume ratio of the wax oil hydrogenation catalyst is 4-20%, the loading volume ratio of the hydrogenation protection catalyst is 2-15%, the loading volume ratio of the hydrodemetallization catalyst is 20-55%, and the loading volume ratio of the hydrodesulfurization and carbon residue removal catalyst is 40-65%.

[0038] Preferably, the wax oil hydrogenation catalyst, the hydrodemetallization catalyst, and the hydrodesulfurization and carbon residue removal catalyst each independently contain a carrier and an active metal component element supported on the carrier, and the active metal component element is selected from at least one of Group VIB metal elements and Group VIII metal elements.

[0039] According to a particularly preferred embodiment, the hydrogenation protected catalyst contains a carrier and an active metal component element supported on the carrier, and the active metal component element is selected from at least one of Group VIB metal elements and Group VIII metal elements; in the hydrogenation protected catalyst, the active metal component element on the carrier is selected from at least one of Group VIB metal elements and Group VIII metal elements.

[0040] Preferably, in the hydroprotection catalyst, the wax oil hydrogenation catalyst, the hydrodemetallization catalyst, and the hydrodesulfurization and carbon residue removal catalyst, the active metal component elements are each independently selected from at least one of the combinations formed by nickel-tungsten, nickel-molybdenum-tungsten, nickel-molybdenum and cobalt-molybdenum.

[0041] Preferably, in the wax oil hydrogenation catalyst, the hydrogenation protection catalyst, the hydrodemetallization catalyst and the hydrodesulfurization and carbon residue removal catalyst, the carrier is independently selected from at least one of aluminum oxide, silicon oxide and titanium oxide.

[0042] Preferably, in the wax oil hydrogenation catalyst, the hydrogenation protection catalyst, the hydrodemetallization catalyst and the hydrodesulfurization and carbon residue removal catalyst, the carriers each independently contain at least one modifying element selected from boron, germanium, zirconium, phosphorus, chlorine and fluorine.

[0043] Preferably, based on the total weight of the carrier, the total weight percentage of the modifying elements germanium and zirconium calculated as metal oxides is 0.1-15%, and the total weight percentage of boron, phosphorus, chlorine and fluorine calculated as elements is 0.1-15%.

[0044] Preferably, in the wax oil hydrogenation catalyst, the content of active metal component elements calculated as oxides is 20-38 wt % based on the total weight of the wax oil hydrogenation catalyst.

[0045] Preferably, the average pore size of the wax oil hydrogenation catalyst is 3 nm-20 nm, and the average particle size is 1.2 mm-4 mm.

[0046] Preferably, the bulk density of the wax oil hydrogenation catalyst is 0.5-1.6 g / cm 3 , with a specific surface area of 80-500m 2 / g.

[0047] According to a preferred embodiment, in the present invention, the wax oil hydrogenation catalyst is at least one of the RN series catalysts developed by the Sinopec Research Institute of Petroleum Processing.

[0048] Preferably, in the hydrogenation protection catalyst, the content of active metal component elements calculated as oxides is 1-12 wt % based on the total weight of the hydrogenation protection catalyst.

[0049] Preferably, the average pore size of the hydrogenation protection catalyst is 18 nm-30 nm, and the average particle size is 1.3 mm-50 mm.

[0050] Preferably, in the hydrodemetallization catalyst, the content of active metal component elements calculated as oxides is 6-15 wt % based on the total weight of the hydrodemetallization catalyst.

[0051] Preferably, the hydrodemetallization catalyst has an average pore size of 10 nm to 20 nm and an average particle size of 0.8 mm to 5 mm.

[0052] Preferably, in the hydrodesulfurization and carbon residue removal catalyst, the content of active metal component elements calculated as oxides is 8-25 wt % based on the total weight of the hydrodesulfurization and carbon residue removal catalyst.

[0053] Preferably, the average pore size of the hydrodesulfurization and carbon residue removal catalyst is 8 nm-15 nm, and the average particle size is 0.6 mm-2 mm.

[0054] Preferably, the characteristics of the hydrogenation protection catalyst, the hydrodemetallization catalyst and the hydrodesulfurization and carbon residue removal catalyst are independently selected from: a bulk density of 0.3-1.2 g / cm 3 , with a specific surface area of 50-400m 2 / g.

[0055] According to a preferred embodiment, in the present invention, the hydrogenation protection catalyst is at least one of the RG series catalysts developed by the Sinopec Research Institute of Petroleum Processing.

[0056] According to a preferred embodiment, in the present invention, the hydrodemetallization catalyst is at least one of the RDM series catalysts and RUF series catalysts developed by the Sinopec Research Institute of Petroleum Processing.

[0057] According to a preferred embodiment, in the present invention, the hydrodesulfurization and carbon residue removal catalyst is at least one of the RMS series catalysts, RCS series catalysts and RSN series catalysts developed by the Sinopec Research Institute of Petroleum Processing.

[0058] According to a preferred embodiment, the method further comprises: in step (1), before the wax oil feedstock is introduced into the first hydrogenation reaction zone, it is first subjected to heat exchange treatment with the hydrogenated residual oil in step (2) without being heated in a heating furnace.

[0059] Preferably, in step (2), before the mixed stream enters the second hydrogenation reaction zone, the vacuum residue is first heated in a heating furnace.

[0060] According to a preferred embodiment, in step (2), the mixed stream contains catalytically cracked light cycle oil, and before the mixed stream enters the second hydrogenation reaction zone, the catalytically cracked light cycle oil is first subjected to heat exchange treatment with the hydrogenated residue oil without being heated in a heating furnace.

[0061] Preferably, the heat exchange treatment includes the following two schemes:

[0062] In a first embodiment, the present invention comprises: first subjecting the hydrogenated residue obtained in the second reaction zone to a heat exchange treatment with the wax oil feedstock and hydrogen, and then subjecting the hydrogenated residue to a heat exchange treatment with the catalytic cracking light cycle oil and hydrogen.

[0063] The second solution of the present invention includes: subjecting a portion of the hydrogenated residue obtained in the second reaction zone to heat exchange treatment with the wax oil feedstock and hydrogen, and subjecting the remaining portion to heat exchange treatment with the catalytic cracking light cycle oil and hydrogen.

[0064] The inventors have discovered that the aforementioned heat exchange method can reduce the energy consumption and operating costs of the device. Furthermore, preheating the hydrogen by heat exchange avoids temperature instability of the residual oil feedstock at the reactor inlet caused by direct hydrogen mixing after the furnace. The method provided by the present invention ensures smoother device operation and improves the heat exchange efficiency of the high-pressure heat exchanger.

[0065] It should be noted that, in the present invention, the average particle size refers to the average maximum straight-line distance between two different points on the cross section of the particle. When the particles of the wax oil hydrogenation catalyst, hydrogenation protection catalyst, hydrodemetallization catalyst, and hydrodesulfurization and carbon residue removal catalyst are spherical, the average particle size refers to the diameter of the catalyst particles.

[0066] The following combination Figure 1 The preferred specific embodiment of the method for hydrotreating residual oil according to the present invention is described, specifically:

[0067] The method is carried out in a fixed bed hydrogenation device containing a first hydrogenation reaction zone R101 and a second hydrogenation reaction zone R102, and includes:

[0068] (1) introducing the wax oil feedstock 4 and fresh hydrogen 5 into the hydrogenated residue oil-hydrogenated wax oil heat exchanger E102 for heat exchange treatment, and then introducing the stream into the first hydrogenation reaction zone R101 containing the wax oil hydrogenation catalyst for the first hydrogenation reaction to obtain hydrogenated wax oil;

[0069] (2) The vacuum residue 1 and the circulating hydrogen 2 are introduced into the heating furnace F101 for heating treatment, and the catalytic cracking light cycle oil 3 or the circulating hydrogen 2 is introduced into the hydrogenated residue oil-hydrogen mixed light cycle oil heat exchanger E101 for heat exchange treatment. Then, the heat exchanged stream is introduced together with the stream from the heating furnace F101 into the second hydrogenation reaction zone R102 for a second hydrogenation reaction to obtain hydrogenated residue oil.

[0070] The method provided by the present invention can remove almost all nitrogen-containing compounds in wax oil, thereby effectively improving the denitrogenation rate of residual oil hydrogenation, and the hydrogen content, desulfurization rate, residual carbon removal rate and demetallization rate are also improved to varying degrees, providing high-quality raw materials for downstream catalytic cracking units, thereby saving production costs.

[0071] The present invention will be described in detail below by way of examples, but the present invention is not limited thereby.

[0072] In the following examples, unless otherwise specified, the catalysts used are all industrial catalysts developed by the Sinopec Research Institute of Petroleum Processing.

[0073] Unless otherwise specified, the following examples use Figure 1 The process flow shown is carried out.

[0074] Wax oil hydrorefining catalyst (V1), brand RN-32V;

[0075] Hydrogenation protection catalyst (G1), brand RG-30B;

[0076] Hydrodemetallization catalyst (M1), brand RDM-202C;

[0077] Hydrodemetallization catalyst (M2), brand RDM-203B;

[0078] The hydrodesulfurization and carbon residue removal catalyst (S1) is RCS-31B.

[0079] The following calculation methods for the removal of residual carbon, desulfurization, denitrification, and removal rates of metallic nickel and vanadium are as follows (the raw oils are all mixtures of the wax oil raw material, vacuum residue, and catalytic cracking light cycle oil (if not used, the amount used is 0) actually used in each embodiment):

[0080] Carbon residue removal rate = (carbon residue content in the raw oil used in the example - carbon residue content in the hydrogenated residue oil obtained in the example) / carbon residue content in the raw oil used in the example * 100%

[0081] Desulfurization rate = (sulfur content in the raw oil used in the example - sulfur content in the hydrotreated residue obtained in the example) / sulfur content in the raw oil used in the example * 100%

[0082] Denitrification rate = (nitrogen content in the raw oil used in the example - nitrogen content in the hydrotreated residue obtained in the example) / nitrogen content in the raw oil used in the example * 100%

[0083] Removal rate of metallic nickel and vanadium = (total content of nickel and vanadium in the raw oil used in the example - total content of nickel and vanadium in the hydrogenated residue obtained in the example) / total content of nickel and vanadium in the raw oil used in the example * 100%.

[0084] Example 1

[0085] This embodiment is carried out using a fixed bed hydrogenation apparatus containing a first hydrogenation reaction zone and a second hydrogenation reaction zone.

[0086] The first hydrogenation reaction zone contains two fixed-bed hydrogenation reactors connected in series; the second hydrogenation reaction zone contains two fixed-bed hydrogenation reactors connected in series.

[0087] The upstream fixed-bed hydrogenation reactor and the downstream fixed-bed hydrogenation reactor in the first hydrogenation reaction zone are both filled with wax oil hydrorefining catalyst V1, with a filling volume ratio of 1:1 (20 ml and 20 ml respectively);

[0088] The upstream fixed-bed hydrogenation reactor in the second hydrogenation reaction zone is sequentially filled with a protective catalyst G1, a hydrodemetallization catalyst M1 and a hydrodemetallization catalyst M2, and the downstream fixed-bed hydrogenation reactor is filled with a hydrodesulfurization and carbon removal catalyst S1; and the filling volume ratio of G1, M1, M2 and S1 is 1:4.8:3.2:11 (25 ml, 120 ml, 80 ml and 275 ml respectively).

[0089] The wax oil raw material used in this example is wax oil A with the properties shown in Table 1; the vacuum residue oil used in this example is vacuum residue A with the properties shown in Table 2. The weight ratio of wax oil A to vacuum residue A is 4:6.

[0090] The specific reaction conditions of this embodiment are:

[0091] After heat exchange treatment, the temperature of the wax oil raw material is 365℃;

[0092] In the first hydrogenation reaction zone, R101, the reaction pressure was 15.5 MPa, the hydrogen-to-oil volume ratio was 600:1, the reaction temperature was 385 °C, and the liquid hourly space velocity was 1.0 h -1 ;

[0093] In the second hydrogenation reaction zone, R102, the reaction pressure is 16.0 MPa, the hydrogen-to-oil volume ratio is 700:1; the reaction temperature of the reactor where the hydrogenation protection catalyst and the hydrodemetallization catalyst are located is 385°C, the reaction temperature of the reactor where the hydrodesulfurization and carbon residue removal catalyst is located is 395°C, and the liquid hourly space velocity of the second hydrogenation reaction zone is 0.18h -1 .

[0094] The total liquid hourly space velocity of the two hydrogenation reaction zones is 0.17h -1 .

[0095] The properties of the hydrotreated residue oil obtained by the method of this embodiment are shown in Table 5, wherein the carbon removal rate, desulfurization rate, denitrification rate, and removal rates of metallic nickel and vanadium are shown in Table 6.

[0096] Comparative Example 1

[0097] This comparative example adopts a process similar to that of Example 1, except that:

[0098] In this comparative example, only the second hydrogenation reaction zone R102 was used, and the first hydrogenation reaction zone R101 was not used. Specifically, the residue oil A shown in Table 4, obtained by mixing the wax oil feedstock with the vacuum residue, was directly introduced into the second hydrogenation reaction zone in the presence of hydrogen and sequentially contacted with a hydrogenation protection catalyst, a hydrodemetallization catalyst (M1 and M2), and a hydrodesulfurization and carbon removal catalyst to produce a hydrogenated residue oil.

[0099] The catalyst loading situation in the second hydrogenation reaction zone R102 is as follows: the upstream fixed-bed hydrogenation reactor is sequentially loaded with the protection catalyst G1, the hydrodemetallization catalyst M1 and the hydrodemetallization catalyst M2, and the downstream fixed-bed hydrogenation reactor is loaded with the hydrodesulfurization and carbon removal catalyst S1; and the loading volume ratio of G1, M1, M2 and S1 is 1:4.8:3.2:11 (25 ml, 120 ml, 80 ml and 275 ml respectively).

[0100] The raw material oils used in this comparative example are the same as those in Example 1, namely wax oil A and vacuum residue oil A, and the usage ratio of the two is the same as that in Example 1.

[0101] The specific reaction conditions of this comparative example are:

[0102] The first hydrogenation reaction zone does not exist;

[0103] In the second hydrogenation reaction zone, R102, the reaction pressure is 16.0 MPa, the hydrogen-to-oil volume ratio is 700:1; the reaction temperature of the reactor where the hydrogenation protection catalyst and the hydrodemetallization catalyst are located is 385°C, the reaction temperature of the reactor where the hydrodesulfurization and carbon residue removal catalyst is located is 395°C, and the liquid hourly space velocity of the second hydrogenation reaction zone is 0.17h -1 .

[0104] The properties of the hydrotreated residue oil obtained by the method of this comparative example are shown in Table 5, wherein the carbon removal rate, desulfurization rate, denitrification rate, and removal rates of metallic nickel and vanadium are shown in Table 6.

[0105] Example 2

[0106] This embodiment is carried out using a process similar to that of embodiment 1, except that:

[0107] In this embodiment, the wax oil raw material used is wax oil B with properties shown in Table 1, and the vacuum residue oil used is vacuum residue B with properties shown in Table 2, and the two are used in a weight ratio of 4:6 (wax oil B: vacuum residue B).

[0108] The properties of the hydrotreated residue oil obtained by the method of this embodiment are shown in Table 5, wherein the carbon removal rate, desulfurization rate, denitrification rate, and removal rates of metallic nickel and vanadium are shown in Table 6.

[0109] Comparative Example 2

[0110] This comparative example was carried out using a process similar to that of comparative example 1, except that:

[0111] In this comparative example, the wax oil raw material used was wax oil B having the properties shown in Table 1, and the vacuum residue oil used was vacuum residue B having the properties shown in Table 2. The two were mixed in a weight ratio of 4:6 (wax oil B: vacuum residue B) (the properties of the residue B obtained after mixing are shown in Table 4) and then used.

[0112] The properties of the hydrotreated residue oil obtained by the method of this comparative example are shown in Table 5, wherein the carbon removal rate, desulfurization rate, denitrification rate, and removal rates of metallic nickel and vanadium are shown in Table 6.

[0113] Example 3

[0114] This embodiment is carried out using a process similar to that of embodiment 1, except that:

[0115] In this embodiment, the catalytic cracking light cycle oil feedstock used is the catalytic cracking light cycle oil A shown in Table 3, the wax oil feedstock used is the wax oil A having the properties shown in Table 1, and the vacuum residue oil used is the vacuum residue oil A having the properties shown in Table 2. The three are used in a weight ratio of 1:4:5 (catalytic cracking light cycle oil A:wax oil A:vacuum residue oil A).

[0116] In this embodiment, the hydrogenated residue oil obtained in the second hydrogenation reaction zone is first subjected to heat exchange treatment with wax oil feedstock and hydrogen, and then subjected to heat exchange treatment with catalytic cracking light cycle oil and hydrogen.

[0117] The rest are the same as in Example 1.

[0118] The properties of the hydrotreated residue oil obtained by the method of this embodiment are shown in Table 5, wherein the carbon removal rate, desulfurization rate, denitrification rate, and removal rates of metallic nickel and vanadium are shown in Table 6.

[0119] Example 4

[0120] This embodiment is carried out using a process similar to that of embodiment 2, except that:

[0121] In this embodiment, the catalytic cracking light cycle oil feedstock used is the catalytic cracking light cycle oil B in Table 3, the wax oil feedstock used is the wax oil B having the properties shown in Table 1, and the vacuum residue oil used is the vacuum residue oil B having the properties shown in Table 2. The three are used in a weight ratio of 1:4:5 (catalytic cracking light cycle oil B:wax oil B:vacuum residue oil B).

[0122] In this embodiment, the hydrogenated residue oil obtained in the second hydrogenation reaction zone is first subjected to heat exchange treatment with wax oil feedstock and hydrogen, and then subjected to heat exchange treatment with catalytic cracking light cycle oil and hydrogen.

[0123] The rest are the same as in Example 2.

[0124] The properties of the hydrotreated residue oil obtained by the method of this embodiment are shown in Table 5, wherein the carbon removal rate, desulfurization rate, denitrification rate, and removal rates of metallic nickel and vanadium are shown in Table 6.

[0125] Example 5

[0126] This embodiment is carried out using a process similar to that of embodiment 1, except that:

[0127] In this embodiment, the wax oil raw material used is wax oil A with properties shown in Table 1, and the vacuum residue oil used is vacuum residue A with properties shown in Table 2, and the two are used in a weight ratio of 5:5 (wax oil A: vacuum residue A).

[0128] The upstream fixed-bed hydrogenation reactor and the downstream fixed-bed hydrogenation reactor in the first hydrogenation reaction zone are both filled with wax oil hydrorefining catalyst V1, with a filling volume ratio of 1:1 (25 ml and 25 ml respectively);

[0129] In the second hydrogenation reaction zone, R102, the reaction pressure is 16.0 MPa, the hydrogen-to-oil volume ratio is 700:1; the reaction temperature of the reactor where the hydrogenation protection catalyst and the hydrodemetallization catalyst are located is 380°C, the reaction temperature of the reactor where the hydrodesulfurization and carbon residue removal catalyst is located is 390°C, and the liquid hourly space velocity of the second hydrogenation reaction zone is 0.19h -1 The total liquid hourly space velocity of the two hydrogenation reaction zones is 0.17h -1 .

[0130] The rest are the same as in Example 1.

[0131] The properties of the hydrotreated residue oil obtained by the method of this embodiment are shown in Table 5, wherein the carbon removal rate, desulfurization rate, denitrification rate, and removal rates of metallic nickel and vanadium are shown in Table 6.

[0132] Comparative Example 3

[0133] This comparative example was carried out using a process similar to that of Example 5, except that:

[0134] In this comparative example, the wax oil raw material used is wax oil A with properties shown in Table 1, and the vacuum residue oil used is vacuum residue A with properties shown in Table 2. The two are used in a weight ratio of 5:5 (wax oil A: vacuum residue A). The raw material after mixing is residue C with properties shown in Table 4.

[0135] In this comparative example, only the second hydrogenation reaction zone R102 was used, and the first hydrogenation reaction zone R101 was not used. Specifically, the wax oil feedstock was mixed with the vacuum residue and then directly introduced into the second hydrogenation reaction zone in the presence of hydrogen, where it sequentially contacted a hydrogenation protection catalyst, a hydrodemetallization catalyst (M1 and M2), and a hydrodesulfurization and carbon removal catalyst to produce a hydrogenated residue.

[0136] The rest are the same as in Example 5.

[0137] The properties of the hydrotreated residue oil obtained by the method of this comparative example are shown in Table 5, wherein the carbon removal rate, desulfurization rate, denitrification rate, and removal rates of metallic nickel and vanadium are shown in Table 6.

[0138] Comparative Example 4

[0139] This comparative example was carried out using a process similar to that of Example 1, except that:

[0140] In this comparative example, the wax oil raw material used is wax oil A with properties shown in Table 1, and the vacuum residue oil used is vacuum residue A with properties shown in Table 2, and the two are used in a weight ratio of 1.5:8.5 (wax oil A: vacuum residue A).

[0141] The first hydrogenation reaction zone contains one fixed-bed hydrogenation reactor, and the second hydrogenation reaction zone contains two fixed-bed hydrogenation reactors connected in series. The fixed-bed hydrogenation reactor in the first hydrogenation reaction zone is loaded with wax oil hydrorefining catalyst V1 with a filling volume of 15 ml.

[0142] The loading conditions in the second hydrogenation reaction zone were the same as those in Example 1.

[0143] The reaction conditions in the first reaction zone were the same as those in Example 1. The liquid hourly space velocity in the second hydrogenation reaction zone was 0.174 h -1 , the other reaction conditions are the same as those in Example 1. The total liquid hourly space velocity of the two reaction zones is 0.17h -1 .

[0144] The properties of the hydrotreated residue oil obtained by the method of this comparative example are shown in Table 5, wherein the carbon removal rate, desulfurization rate, denitrification rate, and removal rates of metallic nickel and vanadium are shown in Table 6.

[0145] Table 1

[0146] Analysis Project Wax Oil A Wax Oil B H,wt% 11.94 12.37 MCR, wt% 0.60 0.36 S, wt% 3.07 0.66 N,wt% 0.091 0.160

[0147] Table 2

[0148] Analysis Project Vacuum residue A Vacuum residue B H,wt% 10.25 11.56 MCR, wt% 20.30 19.16 S, wt% 4.93 2.19 N,wt% 0.43 0.70 Ni+V, ppm 204 125

[0149] Table 3

[0150] Analysis Project Catalytic cracking light cycle oil A FCC Light Cycle Oil B H,wt% 8.75 9.20 MCR, wt% 0 0 S, wt% 0.89 1.25 N, ppm 471 644 Ni+V, ppm 0 0

[0151] Table 4

[0152] Analysis Project H, wt% Carbon residue, wt% S, wt% N, wt% Ni+V, wt% Residue A 11.00 12.31 4.22 0.28 117.0 Residue B 11.34 12.08 1.51 0.48 75.0 Residue C 11.11 10.35 4.05 0.24 99.0

[0153] Table 5

[0154] Analysis Project H, wt% Carbon residue, wt% S, wt% N, wt% Ni+V, wt% Example 1 12.64 2.90 0.15 0.09 1.6 Comparative Example 1 12.45 3.11 0.22 0.10 4.1 Example 2 12.53 4.47 0.14 0.21 8.7 Comparative Example 2 12.34 4.89 0.15 0.24 9.1 Example 3 12.36 2.39 0.11 0.08 1.1 Example 4 12.28 3.52 0.12 0.18 5.2 Example 5 12.68 2.35 0.13 0.08 1.3 Comparative Example 3 12.51 2.55 0.20 0.09 3.1 Comparative Example 4 12.13 4.38 0.33 0.14 8.69

[0155] Table 6

[0156]

[0157]

[0158] The above results show that the hydroprocessing method of the present invention performs well in terms of hydrogen content, desulfurization rate, carbon residue removal rate, and metal removal capacity. The hydroprocessing oil obtained by the present invention provides high-quality feedstock for downstream catalytic cracking units, thereby saving production costs.

[0159] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A method for hydrotreating residual oil, characterized in that: The method is carried out in a fixed bed hydrogenation unit containing a first hydrogenation reaction zone and a second hydrogenation reaction zone, and comprises: (1) In the presence of hydrogen, introducing the wax oil feedstock into a first hydrogenation reaction zone containing a wax oil hydrogenation catalyst to perform a first hydrogenation reaction to obtain hydrogenated wax oil; (2) In the presence of hydrogen, introducing a mixed flow containing vacuum residue oil and the hydrogenated wax oil into a second hydrogenation reaction zone for a second hydrogenation reaction to obtain hydrogenated residue oil; the second hydrogenation reaction zone is sequentially filled with a hydrogenation protection catalyst, a hydrodemetallization catalyst, and a hydrodesulfurization and carbon removal catalyst according to the flow direction of the liquid phase stream; The mixed stream also contains catalytically cracked light cycle oil; Based on the total mass flow rate of the wax oil feedstock, the vacuum residue oil, and the catalytic cracking light cycle oil entering the hydrogenation unit, the mass flow rate of the wax oil feedstock entering the hydrogenation unit is 25-40%, the mass flow rate of the catalytic cracking light cycle oil entering the hydrogenation unit is 10-20%, and the mass flow rate of the vacuum residue oil entering the hydrogenation unit is 50-75%; the total mass flow rate of the wax oil feedstock, the vacuum residue oil, and the catalytic cracking light cycle oil is equal to 100%; In step (1), the wax oil feedstock and hydrogen are first subjected to heat exchange treatment with the hydrogenated residue oil in step (2) without being heated in a heating furnace before being introduced into the first hydrogenation reaction zone; and In step (2), before the mixed stream enters the second hydrogenation reaction zone, the catalytic cracking light cycle oil is first subjected to heat exchange treatment with the hydrogenation residue oil without being heated in a heating furnace, and the vacuum residue oil and hydrogen are first subjected to heating treatment in a heating furnace.

2. The method according to claim 1, wherein In step (1), 1-2 fixed bed reactors are provided in the first hydrogenation reaction zone.

3. The method according to claim 1 or 2, wherein: In step (2), 2-5 fixed bed reactors are provided in the second hydrogenation reaction zone.

4. The method according to claim 1 or 2, wherein: In step (1), the conditions of the first hydrogenation reaction at least meet the following requirements: temperature of 320-430°C, reaction pressure of 6-20 MPa, liquid hourly space velocity of 0.3-2.0 h -1 , the volume ratio of hydrogen to oil is 250-1500:

1.

5. The method according to claim 4, wherein In step (1), the conditions of the first hydrogenation reaction at least meet the following requirements: temperature of 350-410°C, reaction pressure of 10-18 MPa, liquid hourly space velocity of 0.6-1.5 h -1 , the volume ratio of hydrogen to oil is 300-1000:

1.

6. The method according to claim 1 or 2, wherein: In step (1), the asphaltene content in the wax oil feedstock is less than or equal to 500 ppm.

7. The method according to claim 1 or 2, wherein: In step (2), the conditions of the second hydrogenation reaction at least meet the following requirements: temperature of 330-450°C, reaction pressure of 6-25 MPa, liquid hourly space velocity of 0.1-1 h -1 , the volume ratio of hydrogen to oil is 250-1500:

1.

8. The method according to claim 7, wherein: In step (2), the conditions of the second hydrogenation reaction at least meet the following requirements: temperature of 360-430°C, reaction pressure of 12-20 MPa, liquid hourly space velocity of 0.1-0.4 h -1 , the volume ratio of hydrogen to oil is 300-1000:

1.

9. The method according to claim 1 or 2, wherein: Based on the total volume of the catalyst loaded in the hydrogenation device, the loading volume ratio of the wax oil hydrogenation catalyst is 2-25%, the loading volume ratio of the hydrogenation protection catalyst is 1-20%, the loading volume ratio of the hydrodemetallization catalyst is 10-60%, and the loading volume ratio of the hydrodesulfurization and carbon residue removal catalyst is 30-80%.

10. The method according to claim 9, wherein: Based on the total volume of the catalyst loaded in the hydrogenation device, the loading volume ratio of the wax oil hydrogenation catalyst is 4-20%, the loading volume ratio of the hydrogenation protection catalyst is 2-15%, the loading volume ratio of the hydrodemetallization catalyst is 20-55%, and the loading volume ratio of the hydrodesulfurization and carbon residue removal catalyst is 40-65%.

11. The method according to claim 1 or 2, wherein: The wax oil hydrogenation catalyst, the hydrodemetallization catalyst, and the hydrodesulfurization and carbon residue removal catalyst each independently contain a carrier and an active metal component element supported on the carrier, and the active metal component element is selected from at least one of Group VIB metal elements and Group VIII metal elements.

12. The method according to claim 11, wherein The active metal component element is at least one selected from the group consisting of nickel-tungsten, nickel-molybdenum-tungsten, nickel-molybdenum, and cobalt-molybdenum.

13. The method according to claim 11, wherein In the wax oil hydrogenation catalyst, the content of the active metal component element calculated as oxide is 20-38wt% based on the total weight of the wax oil hydrogenation catalyst; and / or In the hydrogenation protection catalyst, the content of the active metal component element calculated as oxide is 1-12 wt % based on the total weight of the hydrogenation protection catalyst; and / or In the hydrodemetallization catalyst, the content of active metal component elements calculated as oxides is 6-15 wt % based on the total weight of the hydrodemetallization catalyst; and / or In the hydrodesulfurization and carbon residue removal catalyst, the content of active metal component elements calculated as oxides is 8-25 wt % based on the total weight of the hydrodesulfurization and carbon residue removal catalyst.

14. The method according to claim 1 or 2, wherein: The wax oil hydrogenation catalyst has an average pore size of 3nm-20nm and an average particle size of 1.2mm-4mm; and / or The average pore size of the hydrogenation protection catalyst is 18 nm to 30 nm, and the average particle size is 1.3 mm to 50 mm; and / or The average pore size of the hydrodemetallization catalyst is 10 nm to 20 nm, and the average particle size is 0.8 mm to 5 mm; and / or The average pore size of the hydrodesulfurization and carbon residue removal catalyst is 8nm-15nm, and the average particle size is 0.6mm-2mm.

15. The method according to claim 1 or 2, wherein: The bulk density of the wax oil hydrogenation catalyst is 0.5-1.6 g / cm 3 , with a specific surface area of 80-500m 2 / g; and / or The characteristics of the hydrogenation protection catalyst, the hydrodemetallization catalyst and the hydrodesulfurization and carbon residue removal catalyst are independently selected from: a bulk density of 0.3-1.2 g / cm 3 , with a specific surface area of 50-400m 2 / g.

16. The method according to claim 11, wherein In the wax oil hydrogenation catalyst, the hydrogenation protection catalyst, the hydrodemetallization catalyst and the hydrodesulfurization and carbon residue removal catalyst, the carrier is independently selected from at least one of aluminum oxide, silicon oxide and titanium oxide.

17. The method according to claim 16, wherein: The carriers independently contain at least one modifying element selected from boron, germanium, zirconium, phosphorus, chlorine and fluorine.

18. The method according to claim 17, wherein Based on the total weight of the carrier, the total weight percentage of germanium and zirconium calculated as metal oxides is 0.1-15%, and the total weight percentage of boron, phosphorus, chlorine and fluorine calculated as elements is 0.1-15%.

Images