A method and system for hydrogenating residual oil

Abstract

This invention relates to the field of residue oil processing, specifically to a method and system for residue oil hydrotreating. The method includes: (1) introducing high-viscosity residue oil and hydrotreated distillate oil into a fixed-bed hydrotreating and viscosity-reducing reaction zone for hydrotreating and viscosity-reducing reaction to obtain a first stream; (2) introducing the first stream into a first separation unit for gas-liquid separation to obtain a first gaseous stream and a liquid stream; (3) introducing the liquid stream into a fixed-bed hydrotreating reaction zone in the presence of hydrogen for hydrotreating reaction to obtain a second stream; (4) introducing the second stream into a second separation unit for gas-liquid separation to obtain a second gaseous stream, hydrotreated naphtha, hydrotreated distillate oil, and hydrotreated heavy oil. The method provided by this invention enables the fixed-bed hydrotreating reaction zone to have higher reaction performance and a longer operating cycle when processing high-viscosity residue oil feedstock.

Description

Technical Field

[0001] The invention relates to the field of residual oil processing, and in particular to a residual oil hydrogenation method and system. Background Art

[0002] The viscosity of the feedstock is one of the important factors affecting the reaction performance of the fixed-bed residue oil hydrogenation technology. This is because residue oil hydrogenation is a process controlled by internal diffusion. The higher the viscosity of the feedstock, the worse the diffusion performance of the residue oil molecules. Under the same process conditions, the impurity removal rate of residue oil hydrogenation is lower.

[0003] In addition, the viscosity of the feedstock is also one of the important factors affecting the system pressure drop of the residue oil hydrotreating unit. Generally, the higher the viscosity of the feedstock, the higher the initial pressure drop of the system. High-viscosity residue oil will also make the catalyst more prone to coking, which will cause the reactor pressure drop to rise rapidly, thus affecting the long-term operation of the unit.

[0004] Limited by the viscosity of the feedstock, conventional fixed-bed residue oil hydrotreating units usually do not only process high-viscosity reduced residue, but introduce low-viscosity oils such as straight-run wax oil, catalytic heavy cycle oil, coker wax oil and catalytic diesel into the feedstock as diluent oil to reduce the viscosity of the feedstock, thereby reducing the impact of the feedstock viscosity on the reaction performance and operation cycle of the fixed-bed residue oil hydrotreating unit.

[0005] Depending on the nature of the raw materials, process conditions and product requirements, the current operating cycle of conventional fixed-bed residue oil hydrotreating units can reach 1-2 years. There are also very few fixed-bed residue oil units in the world that process pure reduced residue, but their operating cycles are very short, only 3-6 months.

[0006] In order to solve the problem of difficulty in processing pure residue with existing fixed-bed residue hydrotreating technology, technicians have also proposed some new technical routes, such as residue viscosity reduction by different methods and combined processes using different reactor types.

[0007] For example, CN101240187A discloses a method for reducing the viscosity and lightening the residue by ultrasonic means. In this method, heavy oil is preheated and then ultrasonically irradiated to significantly reduce the viscosity of the residue. However, this method faces the problems of high energy consumption and difficulty in scale-up.

[0008] CN1335371A discloses a heavy material catalytic hydrogenation method, in which the heavy hydrocarbon raw material is first subjected to mild hydrothermal cracking in a suspended bed reactor, and then enters a fixed bed residual oil hydrogenation unit for hydrogenation treatment, so as to adapt to the heavy and deteriorated residual oil raw material and extend the operating life of the fixed bed residual oil hydrogenation unit. However, this method faces a problem, that is, the catalyst concentration in the suspended bed reactor is low, and the reaction is mainly thermal cracking, which will reduce the stability of the residual oil colloid to a certain extent, and in severe cases, it will cause an increase in carbon deposition of the fixed bed residual oil hydrogenation catalyst, thereby affecting the operating cycle of the fixed bed residual oil hydrogenation unit.

[0009] CN103102934A discloses a method for pretreating inferior heavy oil, in which the visbreaking generated oil is subjected to multi-stage centrifugal separation, wherein each overflow component (light component) is used as the feed of a fixed bed residue oil hydrogenation unit, and the last underflow component (heavy component) is used as the feed of a delayed coking, solvent deasphalting or gasification unit. However, the reaction occurring during the visbreaking process is thermal cracking, and the stability of the residue oil colloid is worse, which is more likely to cause an increase in carbon deposition of the fixed bed residue oil hydrogenation catalyst, thereby affecting the operation cycle of the fixed bed residue oil hydrogenation unit. At the same time, this method also has the problem of low liquid yield of high-value components. Summary of the invention

[0010] The purpose of the present invention is to overcome the defects of the existing residual oil hydrogenation technology, such as poor reaction performance and short operation cycle when processing residual oil raw materials with high viscosity.

[0011] In order to achieve the above object, the first aspect of the present invention provides a method for hydrogenating residual oil, the method comprising:

[0012] (1) introducing high-viscosity residual oil and at least a portion of the hydrogenated distillate oil from the second separation unit into a fixed-bed hydrogenation and viscosity-reducing reaction zone for hydrogenation and viscosity-reducing reaction to obtain a first stream;

[0013] (2) introducing the first logistics into a first separation unit for gas-liquid separation to obtain a first gas phase logistics and a liquid phase logistics;

[0014] (3) In the presence of hydrogen, introducing the liquid phase stream into a fixed bed hydroprocessing reaction zone for hydrogenation reaction to obtain a second stream;

[0015] (4) introducing the second logistics into a second separation unit for gas-liquid separation to obtain a second gas phase logistics, hydrogenated naphtha, hydrogenated distillate oil and hydrogenated heavy oil; recycling at least a portion of the hydrogenated distillate oil back to the fixed bed hydrogenation viscosity-reducing reaction zone;

[0016] The fixed bed hydrogenation and viscosity reduction reaction zone comprises a replaceable reactor, and the replaceable reactor is sequentially loaded with at least one hydrogenation protective agent and at least one hydrogenation and viscosity reduction catalyst according to the flow direction of the liquid phase material;

[0017] The operating conditions in the fixed bed hydrogenation and viscosity reduction reaction zone are controlled so that the viscosity of the liquid phase stream obtained in step (2) at 100°C is ≯200 mm 2 / s;

[0018] And, the viscosity of the high viscosity residual oil at 100°C is greater than 500 mm 2 / s.

[0019] A second aspect of the present invention provides a system for hydrogenating residual oil, the system comprising:

[0020] A fixed bed hydrogenation and viscosity reduction reaction zone, wherein the fixed bed hydrogenation and viscosity reduction reaction zone comprises a replaceable reactor, wherein the replaceable reactor is loaded with at least one hydrogenation protective agent and at least one hydrogenation and viscosity reduction catalyst; the fixed bed hydrogenation and viscosity reduction reaction zone is used to carry out a hydrogenation and viscosity reduction reaction on high viscosity residual oil and at least part of the hydrogenated distillate oil from the second separation unit to obtain a first stream;

[0021] a first separation unit, the first separation unit being in fluid communication with the fixed bed hydroviscosity reduction reaction zone and used for performing gas-liquid separation on the first stream therein to obtain a first gas phase stream and a liquid phase stream;

[0022] A fixed bed hydroprocessing reaction zone, which is in fluid communication with the first separation unit and is used for hydrogenating the liquid phase stream therein to obtain a second stream;

[0023] and a second separation unit, the second separation unit being in fluid communication with the fixed-bed hydroprocessing reaction zone and the fixed-bed hydrogenation viscosity-reducing reaction zone, for performing gas-liquid separation on the second stream therein to obtain a second gas phase stream, hydrogenated naphtha, hydrogenated distillate oil and hydrogenated heavy oil, and recycling at least a portion of the hydrogenated distillate oil back to the fixed-bed hydrogenation viscosity-reducing reaction zone. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The present invention is a process flow chart of a preferred specific implementation mode of the method of the present invention.

[0025] Description of Reference Numerals

[0026] 1 High viscosity residue oil 2-1, 2-2 Fixed bed reactor

[0027] 3 First logistics 4 First separation unit

[0028] 5-1 First gas phase logistics 5-2 Liquid phase logistics

[0029] 6 Hydrogen 7-1, 7-2 Fixed bed reactor

[0030] 8 Second logistics 9 Second separation unit

[0031] 9-1 Second gas phase logistics 9-2 Hydrogenated naphtha

[0032] 9-3 Hydrogenated distillate oil 9-4 Hydrogenated heavy oil DETAILED DESCRIPTION

[0033] The endpoints and any values ​​of the ranges disclosed in this article 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 endpoint values ​​of each range, the endpoint values ​​of each range and the 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 as specifically disclosed in this article.

[0034] In the present invention, unless otherwise specified, the pressures are gauge pressures.

[0035] The inventor of the present invention has found that in order to enable the fixed bed to process high-viscosity low-quality residual oil for a long period of time, technical means must be used to reduce the viscosity of the residual oil raw material, and while reducing the viscosity of the raw material, the colloidal stability of the residual oil raw material cannot be greatly damaged, because the reduction in colloidal stability may cause the precipitation of asphaltene. In this way, even if the viscosity of the raw material is reduced, the fixed bed residual oil hydrogenation unit will cause catalyst coking due to the precipitation of asphaltene, resulting in a shortened operating cycle. In order to avoid greatly damaging the colloidal stability of the residual oil raw material, it is necessary to adopt a method to reduce the proportion of thermal cracking reactions in the viscosity reduction process as much as possible. In view of this, the inventor provides the solution of the present invention.

[0036] As mentioned above, the first aspect of the present invention provides a method for hydrogenating residual oil, the method comprising:

[0037] (1) introducing high-viscosity residual oil and at least a portion of the hydrogenated distillate oil from the second separation unit into a fixed-bed hydrogenation and viscosity-reducing reaction zone for hydrogenation and viscosity-reducing reaction to obtain a first stream;

[0038] (2) introducing the first logistics into a first separation unit for gas-liquid separation to obtain a first gas phase logistics and a liquid phase logistics;

[0039] (3) In the presence of hydrogen, introducing the liquid phase stream into a fixed bed hydroprocessing reaction zone for hydrogenation reaction to obtain a second stream;

[0040] (4) introducing the second logistics into a second separation unit for gas-liquid separation to obtain a second gas phase logistics, hydrogenated naphtha, hydrogenated distillate oil and hydrogenated heavy oil; recycling at least a portion of the hydrogenated distillate oil back to the fixed bed hydrogenation viscosity-reducing reaction zone;

[0041] The fixed bed hydrogenation and viscosity reduction reaction zone comprises a replaceable reactor, and the replaceable reactor is sequentially loaded with at least one hydrogenation protective agent and at least one hydrogenation and viscosity reduction catalyst according to the flow direction of the liquid phase material;

[0042] The operating conditions in the fixed bed hydrogenation and viscosity reduction reaction zone are controlled so that the viscosity of the liquid phase stream obtained in step (2) at 100°C is ≯200 mm 2 / s;

[0043] And, the viscosity of the high viscosity residual oil at 100°C is greater than 500 mm 2 / s.

[0044] Preferably, the operating conditions in the fixed bed hydrogenation and viscosity reduction reaction zone are controlled so that the viscosity of the liquid phase stream obtained in step (2) at 100°C is ≯100 mm 2 The inventors have found that the specific implementation of this preferred embodiment can make the reaction performance of the fixed bed hydroprocessing reaction zone higher and the operation cycle longer.

[0045] Preferably, the initial boiling point of the hydrogenated distillate oil is 160-200°C, and the final boiling point is 320-540°C.

[0046] More preferably, the initial boiling point of the hydrogenated distillate oil is 170-190° C., and the final boiling point is 350-400° C. The inventors have found that the specific implementation of this preferred situation can more effectively reduce the viscosity of the feedstock in the fixed bed hydroprocessing reaction zone.

[0047] Preferably, the initial distillation point of the hydrogenated naphtha is 50-80°C, and the final distillation point is 160-200°C.

[0048] Preferably, the initial boiling point of the hydrogenated heavy oil is 320-540°C.

[0049] Preferably, in the fixed bed hydrogenation and viscosity-reducing reaction zone, the weight ratio of the high-viscosity residual oil to the hydrogenated distillate oil is 1:0.01-1.

[0050] More preferably, in the fixed bed hydrogenation viscosity-reducing reaction zone, the weight ratio of the high-viscosity residual oil to the hydrogenated distillate oil is 1:0.05-0.5.

[0051] Preferably, based on the total volume of the catalyst loaded in the fixed bed hydrogenation and viscosity-breaking reaction zone, the loading amount of the hydrogenation protective agent is 5-95% by volume, and the loading amount of the hydrogenation and viscosity-breaking catalyst is 5-95% by volume.

[0052] Preferably, the hydrogenation protective agent contains a carrier and an active component loaded on the carrier, the carrier is selected from at least one of aluminum oxide, silicon dioxide, and titanium oxide, the active component contains at least one selected from Group VIB metal elements and Group VIII metal elements, and based on the total weight of the hydrogenation protective agent, the content of the active component in terms of oxide is 0-12% by weight, and the balance is the carrier.

[0053] Preferably, the average particle size of the hydrogenation protective agent is 3-50 mm, and the average pore size is 18-400 nm.

[0054] Preferably, the hydrogenation and visbreaking catalyst contains a carrier and an active component supported on the carrier, the carrier is selected from at least one of alumina, silica, and titanium oxide, the active component contains at least one selected from Group VIB metal elements and Group VIII metal elements, and based on the total weight of the hydrogenation and visbreaking catalyst, the content of the active component in terms of oxide is 3-30% by weight, and the balance is the carrier.

[0055] More preferably, in the hydrogenation visbreaking catalyst, the content of the silicon dioxide is 0.1-10 wt % based on the total weight of the hydrogenation visbreaking catalyst. The inventors have found that the specific implementation of this preferred situation can make the reaction performance of the fixed bed hydroprocessing reaction zone higher and the operation cycle longer.

[0056] Preferably, the average particle size of the hydrogenation viscosity-reducing catalyst is 0.8-3 mm, and the average pore size is 10-30 nm.

[0057] Preferably, in the fixed bed hydrogenation and viscosity-reducing reaction zone, the replaceable reactor satisfies at least one of the conditions (I), (II) or (III):

[0058] (I) the hydrogenation protective agent and the hydrogenation viscosity-reducing catalyst loaded in the replaceable reactor are configured to be replaceable online;

[0059] (II) the replaceable reactor comprises at least two fixed bed reactors arranged in parallel, and at least one of the fixed bed reactors connected in parallel is online;

[0060] (III) The replaceable reactor is partially or completely removed during operation.

[0061] In the present invention, the fixed bed hydroprocessing reaction zone can be loaded with various residual oil hydroprocessing catalysts known in the art, including hydrogenation protective agents, hydrodemetallization agents, hydrodesulfurization agents and hydrodecarbonization catalysts, and the grading ratios of various catalysts can also be carried out according to conventional techniques in the art. The embodiments of the present invention exemplarily list residual oil hydroprocessing catalysts, which should not be construed as limiting the present invention by those skilled in the art.

[0062] Preferably, the fixed bed hydroprocessing reaction zone is filled with at least one residue hydroprocessing catalyst, the residue hydroprocessing catalyst contains a carrier and an active component loaded on the carrier, the carrier is selected from at least one of alumina, silica, and titanium oxide, the active component contains at least one selected from Group VIB metal elements and Group VIII metal elements, and based on the total weight of the residue hydroprocessing catalyst, the content of the active component in terms of oxide is 1-35% by weight, and the balance is the carrier.

[0063] Preferably, in the residue hydroprocessing catalyst, the active component is selected from at least one of nickel-tungsten, nickel-tungsten-cobalt, nickel-molybdenum or cobalt-molybdenum.

[0064] Preferably, the residue hydroprocessing catalyst has an average particle size of 0.8-50 mm and an average pore size of 7-400 nm.

[0065] Preferably, the bulk density of the residue hydroprocessing catalyst is 0.3-1.2 g / cm 3 , with a specific surface area of ​​50-400m 2 / g.

[0066] The residue oil hydroprocessing catalyst and the hydroviscosity reduction catalyst of the present invention may further contain an additive. For example, the additive may be an oxide of phosphorus.

[0067] In the present invention, in the fixed bed hydroprocessing reaction zone, illustratively, the order of loading the catalyst is to load the hydrogenation protective agent, the hydrodemetallization agent and the hydrodesulfurization agent in sequence.

[0068] According to a particularly preferred embodiment, in the present invention, in the fixed bed hydroprocessing reaction zone, according to the flow direction of the liquid phase material, the pore size and particle size of the residue hydroprocessing catalyst gradually decrease, and the content of the active component gradually increases.

[0069] Preferably, the fixed bed hydroprocessing reaction zone contains at least two fixed bed reactors arranged in series.

[0070] Preferably, the reaction temperature of the fixed bed hydrogenation viscosity reduction reaction zone is 300-450°C, and the liquid hourly volume space velocity is 0.10-10.0h -1 , the reaction pressure is 0.1-5Mpa.

[0071] More preferably, the reaction temperature of the fixed bed hydrogenation viscosity reduction reaction zone is 350-420°C, and the liquid hourly volume space velocity is 0.5-5.0h -1 , the reaction pressure is 0.5-3MPa.

[0072] The inventors have found that setting a low-pressure hydrogenation viscosity reduction reaction zone before the fixed-bed hydroprocessing reaction zone can more effectively reduce the viscosity of the feedstock in the fixed-bed hydroprocessing reaction zone.

[0073] Preferably, the reaction temperature of the fixed bed hydroprocessing reaction zone is 300-460°C, the reaction pressure is 6-25MPa, and the liquid hourly volume space velocity is 0.1-1h -1 , the volume ratio of hydrogen to oil is 250-1500.

[0074] More preferably, the reaction temperature of the fixed bed hydroprocessing reaction zone is 350-420°C, the reaction pressure is 12-20 MPa, and the liquid hourly volume space velocity is 0.15-0.4 h -1 , the volume ratio of hydrogen to oil is 300-1000.

[0075] Preferably, the viscosity of the high viscosity residual oil at 100°C is greater than 800 mm 2 / s.

[0076] Preferably, the high-viscosity residual oil is selected from at least one of atmospheric residual oil, vacuum residual oil and heavy oil.

[0077] The following combination Figure 1 A preferred process flow of a specific embodiment of the method for hydrogenating residual oil of the present invention is provided:

[0078] The high viscosity residue 1 and at least part of the hydrogenated distillate 9-3 from the second separation unit 9 are mixed and introduced into a fixed bed hydrogenation viscosity reduction reaction zone for hydrogenation viscosity reduction reaction. The fixed bed hydrogenation viscosity reduction reaction zone contains two fixed bed reactors arranged in parallel, namely, a fixed bed reactor 2-1 and a fixed bed reactor 2-2. The two reactors are online in turn to react and obtain a first stream 3;

[0079] Introducing the first stream 3 into the first separation unit 4 for gas-liquid separation to obtain a first gas phase stream 5-1 and a liquid phase stream 5-2;

[0080] The liquid phase stream 5-2 and hydrogen 6 are mixed and introduced into a fixed bed hydroprocessing reaction zone for hydrogenation reaction, wherein the fixed bed hydroprocessing reaction zone contains two fixed bed reactors arranged in series, namely, a fixed bed reactor 7-1 and a fixed bed reactor 7-2, to obtain a second stream 8;

[0081] The second logistics 8 is introduced into the second separation unit 9 for gas-liquid separation to obtain a second gas phase logistics 9-1, hydrogenated naphtha 9-2, hydrogenated distillate oil 9-3 and hydrogenated heavy oil 9-4; at least a portion of the hydrogenated distillate oil 9-3 is recycled back to the fixed bed hydrogenation viscosity reduction reaction zone.

[0082] In a preferred embodiment of the present invention, compared with the prior art, the method provided by the present invention can effectively reduce the viscosity of the liquid phase flow entering the fixed bed hydroprocessing reaction zone without significantly destroying the colloid stability of the residual oil feedstock, thereby effectively improving the reaction performance of the fixed bed hydroprocessing reaction zone and extending its operation cycle.

[0083] As mentioned above, the second aspect of the present invention provides a system for hydrogenating residual oil, the system comprising:

[0084] A fixed bed hydrogenation and viscosity reduction reaction zone, wherein the fixed bed hydrogenation and viscosity reduction reaction zone comprises a replaceable reactor, wherein the replaceable reactor is loaded with at least one hydrogenation protective agent and at least one hydrogenation and viscosity reduction catalyst; the fixed bed hydrogenation and viscosity reduction reaction zone is used to carry out a hydrogenation and viscosity reduction reaction on high viscosity residual oil and at least part of the hydrogenated distillate oil from the second separation unit to obtain a first stream;

[0085] a first separation unit, the first separation unit being in fluid communication with the fixed bed hydroviscosity reduction reaction zone and used for performing gas-liquid separation on the first stream therein to obtain a first gas phase stream and a liquid phase stream;

[0086] A fixed bed hydroprocessing reaction zone, which is in fluid communication with the first separation unit and is used for hydrogenating the liquid phase stream therein to obtain a second stream;

[0087] and a second separation unit, the second separation unit being in fluid communication with the fixed-bed hydroprocessing reaction zone and the fixed-bed hydrogenation viscosity-reducing reaction zone, for performing gas-liquid separation on the second stream therein to obtain a second gas phase stream, hydrogenated naphtha, hydrogenated distillate oil and hydrogenated heavy oil, and recycling at least a portion of the hydrogenated distillate oil back to the fixed-bed hydrogenation viscosity-reducing reaction zone.

[0088] Preferably, in the fixed bed hydrogenation and viscosity-reducing reaction zone, the replaceable reactor satisfies at least one of the conditions (I), (II) or (III):

[0089] (I) the hydrogenation protective agent and the hydrogenation viscosity-reducing catalyst loaded in the replaceable reactor are configured to be replaceable online;

[0090] (II) the replaceable reactor comprises at least two fixed bed reactors arranged in parallel, and at least one of the fixed bed reactors arranged in parallel is online;

[0091] (III) The replaceable reactor is partially or completely removed during operation.

[0092] Preferably, the fixed bed hydroprocessing reaction zone contains at least two fixed bed reactors arranged in series.

[0093] In the method provided by the present invention, a hydrogenation viscosity-reducing reaction zone is arranged before a fixed-bed hydroprocessing reaction zone. The hydrogenation viscosity-reducing reaction zone adopts a fixed-bed reactor and has a high catalyst concentration. Hydrogenated distillate oil is used as a diluent oil product and a hydrogen donor and mixed with high-viscosity residual oil in the fixed-bed hydrogenation viscosity-reducing reaction zone. At the same time, by loading a hydrogenation viscosity-reducing catalyst with a certain cracking function and controlling the process conditions of the hydrogenation viscosity-reducing reaction zone, the proportion of thermal cracking reaction in the hydrogenation viscosity-reducing reaction is reduced as much as possible. Under the premise of not greatly destroying the colloidal stability of the residual oil raw material, the viscosity of the liquid phase flow entering the fixed-bed hydroprocessing reaction zone can be effectively reduced, thereby effectively improving the reaction performance of the fixed-bed hydroprocessing reaction zone and extending its operation cycle.

[0094] In the method provided by the present invention, the fixed bed hydrogenation and viscosity reduction reaction zone adopts a replaceable reactor, which can avoid the long-term operation of the fixed bed hydroprocessing reaction zone being affected by the increase in the reactor pressure drop in the hydrogenation and viscosity reduction reaction zone.

[0095] The present invention uses hydrogenated distillate oil as diluent oil for high-viscosity residue oil and hydrogen supply agent for hydrogenation and viscosity reduction reaction zone, which can more effectively reduce the viscosity of raw materials in the fixed-bed hydroprocessing reaction zone and reduce equipment investment in the hydrogenation and viscosity reduction reaction zone.

[0096] The present invention will be described in detail below by way of examples.

[0097] In the following examples, all raw materials used are commercially available unless otherwise specified.

[0098] The composition and properties of the catalysts used in the following examples are shown in Table 1, wherein G represents a hydrogenation protective agent, V represents a hydrogenation viscosity-reducing catalyst, M represents a hydrogenation demetallizing agent, and S represents a hydrodesulfurizing agent, wherein the contents are calculated based on the total weight of the catalyst, and the remainder is a carrier.

[0099] The properties of the raw material high viscosity residual oil used in the following examples are as follows:

[0100] The density at 20°C is 1.024 g / cm 3 , the viscosity at 100℃ is 1278mm 2 / s, the residual carbon content was 20.1% by mass, the sulfur content was 5.44% by mass, the metal (Ni+V) content was 201 μg / g, and the asphaltene content was 9.5% by mass.

[0101] The properties of the hydrogenated distillate oil in the following example are as follows:

[0102] The density at 20°C is 0.86 g / cm 3 , the viscosity at 100℃ is 1.92mm 2 / s, and the sulfur content is 0.015 mass%.

[0103] Table 1

[0104] project G V M S <![CDATA[MO3 / (wt%)]]> 5.6 11.5 8.4 15.2 NiO / (weight%) 1.1 2.0 1.5 3.5 <![CDATA[P2O5 / (wt%)]]> - 1.0 1.0 2.0 <![CDATA[SiO2 / (wt%)]]> - 5.0 - - Pore ​​volume / (mL / g) 0.85 0.65 0.68 0.60 <![CDATA[Specific surface area / (m 2 / g)]]> 110 150 165 180 Average particle size / mm 3.0 1.8 1.3 1.0 Average pore size / nm 25 15 14 11

[0105] Example 1

[0106] In this embodiment, a fixed bed hydrogenation viscosity reduction reaction zone is provided, wherein a fixed bed reactor is provided in the fixed bed hydrogenation viscosity reduction reaction zone, and a hydrogenation protective agent G and a hydrogenation viscosity reduction catalyst V are sequentially loaded in the fixed bed reactor according to the flow direction of the liquid phase material;

[0107] The high viscosity residual oil and the hydrogenated distillate oil (distillation range is 180-350° C.) from the second separation unit are mixed and introduced into the fixed bed hydrogenation viscosity reduction reaction zone for hydrogenation viscosity reduction reaction to obtain a first logistics; the first logistics is introduced into the separation unit for gas-liquid separation to obtain a gas phase logistics and a liquid phase logistics.

[0108] The loading amount of the catalyst is shown in Table 2, the reaction conditions are shown in Table 3, and the properties of the high viscosity residual oil and the liquid phase flow are shown in Table 4.

[0109] Example 2

[0110] This example is carried out using a method similar to that of Example 1, except that the reaction conditions are different.

[0111] The loading amount of the catalyst is shown in Table 2, the reaction conditions are shown in Table 3, and the properties of the high viscosity residual oil and the liquid phase flow are shown in Table 4.

[0112] Example 3

[0113] This example is carried out in a similar manner to Example 1, except that: the fixed bed reactor is sequentially loaded with a hydrogenation protective agent G and a hydrogenation demetallization agent M according to the flow direction of the liquid phase material; and the reaction conditions are different.

[0114] The loading amount of the catalyst is shown in Table 2, the reaction conditions are shown in Table 3, and the properties of the high viscosity residual oil and the liquid phase flow are shown in Table 4.

[0115] Comparative Example 1

[0116] This comparative example was carried out in a similar manner to Example 2, except that only porcelain balls were loaded in the fixed bed reactor to simulate hydrovisbreaking.

[0117] Among them, the loading amount is shown in Table 2, the reaction conditions are shown in Table 3, and the properties of the high-viscosity residual oil and the liquid phase flow are shown in Table 4.

[0118] Example 4

[0119] In this embodiment, a fixed-bed hydrogenation viscosity-reducing reaction zone and a fixed-bed hydroprocessing reaction zone are provided. A fixed-bed reactor is provided in each of the fixed-bed hydrogenation viscosity-reducing reaction zone and the fixed-bed hydroprocessing reaction zone. According to the flow direction of the liquid phase material, the fixed-bed reactor in the fixed-bed hydrogenation viscosity-reducing reaction zone is sequentially filled with a hydrogenation protective agent G and a hydrogenation viscosity-reducing catalyst V, and the fixed-bed reactor in the fixed-bed hydroprocessing reaction zone is sequentially filled with a hydrogenation protective agent G, a hydrogenation demetallization agent M, and a hydrogenation desulfurization agent S;

[0120] The high-viscosity residual oil and the hydrogenated distillate oil (distillation range is 180-350° C.) from the second separation unit are mixed and introduced into the fixed-bed hydrogenation viscosity-reducing reaction zone for hydrogenation viscosity-reducing reaction to obtain a first stream; the first stream is introduced into the first separation unit for gas-liquid separation to obtain a first gas phase stream and a liquid phase stream; the liquid phase stream and hydrogen are mixed and introduced into the fixed-bed hydroprocessing reaction zone for hydrogenation reaction to obtain a second stream; the second stream is introduced into the second separation unit for gas-liquid separation to obtain a second gas phase stream, hydrogenated naphtha, hydrogenated distillate oil (distillation range is 180-350° C.) and hydrogenated heavy oil; part of the hydrogenated distillate oil is recycled back to the fixed-bed hydrogenation viscosity-reducing reaction zone.

[0121] This example conducts a long-term stability test. In which, the fixed bed hydrogenation viscosity reduction reaction zone controls the viscosity of the liquid phase flow at 100°C to ≯200mm by increasing the reaction temperature. 2 / s, the fixed bed hydroprocessing reaction zone controls the sulfur content of the hydrogenated heavy oil to not exceed 0.5 weight % by increasing the reaction temperature;

[0122] The standard for replacing the catalyst in the fixed-bed hydrogenation viscosity reduction reaction zone is that the reactor pressure drop reaches 0.7 MPa or the reaction temperature reaches 410°C, and the standard for shutting down the fixed-bed hydroprocessing reaction zone is that the reactor pressure drop reaches 0.7 MPa or the reaction temperature reaches 410°C.

[0123] The loading amount of the catalyst is shown in Table 2, the reaction conditions are shown in Table 3, and the properties of the high-viscosity residual oil, the liquid phase stream and the hydrogenated heavy oil are shown in Table 4.

[0124] Test results: After 5000 hours of operation, the pressure drop in the fixed bed hydrogenation viscosity reduction reaction zone of this embodiment increased to 0.70 MPa. After replacing the catalyst, the operation continued. After 9200 hours of operation, the reaction temperature of the fixed bed hydroprocessing reaction zone increased to 410°C, and the system was shut down.

[0125] Example 5

[0126] This example is carried out in a similar manner to Example 4, except that: the fixed bed hydrogenation viscosity reduction reaction zone controls the viscosity of the liquid phase stream at 100°C to ≯100 mm by increasing the reaction temperature. 2 / s.

[0127] The loading amount of the catalyst is shown in Table 2, the reaction conditions are shown in Table 3, and the properties of the high-viscosity residual oil, the liquid phase stream and the hydrogenated heavy oil are shown in Table 4.

[0128] Test results: After 4300 hours of operation, the pressure drop in the fixed bed hydrogenation viscosity reduction reaction zone of this embodiment rose to 0.70 MPa. After replacing the catalyst, the operation was continued. After 8500 hours of operation, the pressure drop in the fixed bed hydrogenation viscosity reduction reaction zone rose to 0.70 MPa. After replacing the catalyst again, the operation was continued. After 10800 hours of operation, the reaction temperature of the fixed bed hydroprocessing reaction zone rose to 410°C, and the system was shut down.

[0129] Comparative Example 2

[0130] In this comparative example, a fixed bed hydroprocessing reaction zone is set, and a fixed bed reactor is set in the fixed bed hydroprocessing reaction zone. According to the flow direction of the liquid phase material, the fixed bed reactor is filled with a hydrogenation protective agent G, a hydrodemetallization agent M, and a hydrodesulfurization agent S in sequence;

[0131] The high viscosity residual oil and hydrogen are mixed and introduced into a fixed bed hydroprocessing reaction zone for hydrogenation reaction to obtain a second logistics; the second logistics is introduced into a second separation unit for gas-liquid separation to obtain a second gas phase logistics, hydrogenated naphtha, hydrogenated distillate oil (distillation range is 180-350°C) and hydrogenated heavy oil.

[0132] This comparative example is subjected to a long-term stability test. In which, the fixed-bed hydroprocessing reaction zone controls the sulfur content of the hydrogenated heavy oil to be no more than 0.5% by weight by increasing the reaction temperature;

[0133] The shutdown criteria for the fixed bed hydroprocessing reaction zone are that the reactor pressure drop reaches 0.7 MPa or the reaction temperature reaches 410°C.

[0134] The loading amount of the catalyst is shown in Table 2, the reaction conditions are shown in Table 3, and the properties of the high-viscosity residual oil and the hydrogenated heavy oil are shown in Table 4.

[0135] Test results: After the comparative example was run for 5100 h, the pressure drop in the fixed bed hydroprocessing reaction zone rose to 0.70 MPa and the system was shut down.

[0136] Table 2

[0137]

[0138] Table 3

[0139]

[0140] Table 4

[0141]

[0142]

[0143] It can be seen from the results in Table 4 that in Examples 1-3, the fixed bed hydrogenation viscosity reduction reaction zone effectively reduces the viscosity of the inferior residue oil. In addition, the viscosity of the liquid phase stream can be adjusted as needed by controlling the blending ratio of the hydrogenated distillate oil, the graded catalyst in the fixed bed hydrogenation viscosity reduction zone and the reaction conditions.

[0144] Compared with Example 2, on the one hand, the viscosity reduction effect of hydrovisbreaking is worse than that of the fixed-bed hydrovisbreaking reaction zone provided in the present invention, and on the other hand, hydrovisbreaking also leads to an increase in the asphaltene content of the liquid phase stream, that is, its colloidal stability becomes poor.

[0145] Examples 4-5 were shut down after running for 9200 h and 10800 h respectively, while Comparative Example 2 without a fixed bed hydrogenation viscosity reduction reaction zone was shut down after running for only 5100 h, indicating that setting a fixed bed hydrogenation viscosity reduction reaction zone can significantly extend the operating cycle of the fixed bed hydroprocessing reaction zone.

[0146] It can be seen from the above results that the method provided by the present invention can effectively reduce the viscosity of the liquid phase flow entering the fixed bed hydroprocessing reaction zone without significantly destroying the colloidal stability of the residual oil feedstock, thereby effectively improving the reaction performance of the fixed bed hydroprocessing reaction zone when processing residual oil feedstock with high viscosity and extending its operation cycle; at the same time, the fixed bed hydroprocessing viscosity reduction reaction zone adopts a replaceable reactor, which can avoid the long-term operation of the fixed bed hydroprocessing reaction zone being affected by the increase in the reactor pressure drop of the hydroprocessing viscosity reduction reaction zone; and the use of hydrogenated distillate oil as a diluent oil for high-viscosity residual oil and a hydrogen supply agent for the hydroprocessing viscosity reduction reaction zone can more effectively reduce the viscosity of the feedstock in the fixed bed hydroprocessing reaction zone.

[0147] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for hydrogenating residual oil, characterized in that: The method includes: (1) introducing high viscosity residual oil and at least a portion of the hydrogenated distillate oil from the second separation unit into a fixed bed hydrogenation and viscosity reduction reaction zone for hydrogenation and viscosity reduction reaction to obtain a first stream; (2) introducing the first logistics into a first separation unit for gas-liquid separation to obtain a first gas phase logistics and a liquid phase logistics; (3) In the presence of hydrogen, introducing the liquid phase stream into a fixed bed hydroprocessing reaction zone for hydrogenation reaction to obtain a second stream; (4) introducing the second stream into a second separation unit for gas-liquid separation to obtain a second gas phase stream, hydrogenated naphtha, hydrogenated distillate oil and hydrogenated heavy oil; recycling at least a portion of the hydrogenated distillate oil back to the fixed bed hydrogenation viscosity-reducing reaction zone; The fixed bed hydrogenation and viscosity reduction reaction zone comprises a replaceable reactor, and the replaceable reactor is sequentially loaded with at least one hydrogenation protective agent and at least one hydrogenation and viscosity reduction catalyst according to the flow direction of the liquid phase material; The operating conditions in the fixed bed hydrogenation and viscosity reduction reaction zone are controlled so that the viscosity of the liquid phase stream obtained in step (2) at 100°C is ≯200 mm 2 / s; And, the viscosity of the high viscosity residual oil at 100°C is greater than 500 mm 2 / s; The initial boiling point of the hydrogenated distillate oil is 160-200°C, and the final boiling point is 320-540°C; In the fixed bed hydrogenation and viscosity reduction reaction zone, the weight ratio of the high viscosity residual oil to the hydrogenated distillate oil is 1:0.01-1.

2. The method according to claim 1, wherein: The operating conditions in the fixed bed hydrogenation and viscosity reduction reaction zone are controlled so that the viscosity of the liquid phase stream obtained in step (2) at 100°C is ≯100 mm 2 / s.

3. The method according to claim 1 or 2, wherein: The initial boiling point of the hydrogenated distillate oil is 170-190°C, and the final boiling point is 350-400°C.

4. The method according to claim 1 or 2, wherein: The weight ratio of the high viscosity residual oil to the hydrogenated distillate oil is 1:0.05-0.

5.

5. The method according to claim 1 or 2, wherein: Based on the total volume of the catalyst loaded in the fixed bed hydrogenation viscosity-reducing reaction zone, the loading amount of the hydrogenation protective agent is 5-95% by volume, and the loading amount of the hydrogenation viscosity-reducing catalyst is 5-95% by volume.

6. The method according to claim 1 or 2, wherein: The hydrogenation protective agent contains a carrier and an active component loaded on the carrier, the carrier is selected from at least one of aluminum oxide, silicon dioxide, and titanium oxide, the active component contains at least one of metal elements of Group VIB and Group VIII, and the content of the active component in terms of oxide is 0-12% by weight based on the total weight of the hydrogenation protective agent.

7. The method according to claim 1 or 2, wherein: The average particle size of the hydrogenation protective agent is 3-50 mm, and the average pore size is 18-400 nm.

8. The method according to claim 1 or 2, wherein: The hydrogenation and visbreaking catalyst contains a carrier and an active component supported on the carrier, the carrier is selected from at least one of aluminum oxide, silicon dioxide, and titanium oxide, the active component contains at least one of Group VIB metal elements and Group VIII metal elements, and the content of the active component in terms of oxide is 3-30% by weight based on the total weight of the hydrogenation and visbreaking catalyst.

9. The method according to claim 8, wherein: In the hydrogenation and visbreaking catalyst, the content of the silicon dioxide is 0.1-10 wt % based on the total weight of the hydrogenation and visbreaking catalyst.

10. The method according to claim 1 or 2, wherein: The average particle size of the hydrogenation and viscosity-reducing catalyst is 0.8-3 mm, and the average pore size is 10-30 nm.

11. The method according to claim 1 or 2, wherein: In the fixed bed hydrogenation and viscosity reduction reaction zone, the replaceable reactor satisfies one of the conditions (I), (II) or (III): (I) the hydrogenation protective agent and the hydrogenation viscosity-reducing catalyst loaded in the replaceable reactor are configured to be replaceable online; (II) the replaceable reactor comprises at least two fixed bed reactors arranged in parallel, and at least one of the fixed bed reactors connected in parallel is online; (III) The replaceable reactor is partially or completely removed during operation.

12. The method according to claim 1 or 2, wherein: The fixed bed hydroprocessing reaction zone is filled with at least one residual oil hydroprocessing catalyst, the residual oil hydroprocessing catalyst contains a carrier and an active component loaded on the carrier, the carrier is selected from at least one of aluminum oxide, silicon dioxide, and titanium oxide, the active component contains at least one selected from Group VIB metal elements and Group VIII metal elements, and based on the total weight of the residual oil hydroprocessing catalyst, the content of the active component in terms of oxide is 1-35% by weight.

13. The method according to claim 12, wherein: The active component is selected from at least one of nickel-tungsten, nickel-tungsten-cobalt, nickel-molybdenum or cobalt-molybdenum.

14. The method according to claim 12, wherein: The average particle size of the residue oil hydroprocessing catalyst is 0.8-50 mm, and the average pore size is 7-400 nm.

15. The method according to claim 12, wherein: The bulk density of the residue hydroprocessing catalyst is 0.3-1.2 g / cm 3 , with a specific surface area of ​​50-400m 2 / g.

16. The method according to claim 1 or 2, wherein: The fixed bed hydroprocessing reaction zone contains at least two fixed bed reactors arranged in series.

17. The method according to claim 1 or 2, wherein: The reaction temperature of the fixed bed hydrogenation and viscosity reduction reaction zone is 300-450°C, and the liquid hourly volume space velocity is 0.10-10.0h -1 , the reaction pressure is 0.1-5MPa.

18. The method according to claim 17, wherein: The reaction temperature of the fixed bed hydrogenation and viscosity reduction reaction zone is 350-420°C, and the liquid hourly volume space velocity is 0.5-5.0h -1 , the reaction pressure is 0.5-3MPa.

19. The method according to claim 1 or 2, wherein: The reaction temperature of the fixed bed hydroprocessing reaction zone is 300-460°C, the reaction pressure is 6-25MPa, and the liquid hourly volume space velocity is 0.1-1h -1 , the volume ratio of hydrogen to oil is 250-1500.

20. The method according to claim 19, wherein: The reaction temperature of the fixed bed hydroprocessing reaction zone is 350-420°C, the reaction pressure is 12-20MPa, and the liquid hourly volume space velocity is 0.15-0.4h -1 , the volume ratio of hydrogen to oil is 300-1000.

21. The method according to claim 1 or 2, wherein: The viscosity of the high viscosity residual oil at 100°C is greater than 800 mm 2 / s.

22. The method according to claim 1 or 2, wherein: The high-viscosity residual oil is atmospheric residual oil and / or vacuum residual oil.

23. A system for the method for hydrogenating residual oil according to any one of claims 1 to 22, characterized in that: The system includes: A fixed bed hydrogenation and viscosity reduction reaction zone, wherein the fixed bed hydrogenation and viscosity reduction reaction zone comprises a replaceable reactor, wherein the replaceable reactor is loaded with at least one hydrogenation protective agent and at least one hydrogenation and viscosity reduction catalyst; the fixed bed hydrogenation and viscosity reduction reaction zone is used to carry out a hydrogenation and viscosity reduction reaction on high viscosity residual oil and at least part of the hydrogenated distillate oil from the second separation unit to obtain a first stream; a first separation unit, the first separation unit being in fluid communication with the fixed bed hydroviscosity reduction reaction zone and used for performing gas-liquid separation on the first stream therein to obtain a first gas phase stream and a liquid phase stream; a fixed bed hydroprocessing reaction zone, which is in fluid communication with the first separation unit and is used for hydrogenating the liquid phase stream therein to obtain a second stream; and a second separation unit, the second separation unit being in fluid communication with the fixed-bed hydroprocessing reaction zone and the fixed-bed hydrogenation viscosity-reducing reaction zone, for performing gas-liquid separation on the second stream therein to obtain a second gas phase stream, hydrogenated naphtha, hydrogenated distillate oil and hydrogenated heavy oil, and recycling at least a portion of the hydrogenated distillate oil back to the fixed-bed hydrogenation viscosity-reducing reaction zone.

24. The system of claim 23, wherein: In the fixed bed hydrogenation and viscosity reduction reaction zone, the replaceable reactor satisfies one of the conditions (I), (II) or (III): (I) the hydrogenation protective agent and the hydrogenation viscosity-reducing catalyst loaded in the replaceable reactor are configured to be replaceable online; (II) the replaceable reactor comprises at least two fixed bed reactors arranged in parallel, and at least one of the fixed bed reactors arranged in parallel is online; (III) The replaceable reactor is partially or completely removed during operation.

25. A system according to claim 23 or 24, wherein: The fixed bed hydroprocessing reaction zone contains at least two fixed bed reactors arranged in series.

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