A process for processing low quality residual oil

Abstract

The present application relates to the field of processing inferior residual oil, and discloses a method for processing inferior residual oil, which comprises the following steps: (1) performing a mild catalytic cracking reaction on inferior residual oil I to obtain a mild catalytic cracking reaction product; (2) separating the mild catalytic cracking reaction product to obtain catalytic cracking heavy oil; (3) performing a hydrodesulfurization reaction on the catalytic cracking heavy oil to obtain a hydrodesulfurization reaction product; and (4) separating the hydrodesulfurization reaction product to obtain hydrogenated heavy oil. The method for processing inferior residual oil provided by the present application combines catalytic cracking heavy oil hydroprocessing and catalytic cracking, can maximize the production of light oil and low-sulfur marine fuel oil from inferior residual oil, and thus reduces the production cost of the light oil and low-sulfur marine fuel oil prepared by the method.

Description

Technical Field

[0001] This invention relates to the field of processing inferior residual oil, and more specifically, to a method for processing inferior residual oil. Background Technology

[0002] Increasingly stringent environmental regulations worldwide have led to the widespread use of clean fuels. Following the clean production of bulk oils such as gasoline and diesel, low-sulfur clean marine fuel oil (referred to as marine fuel) has become one of the key oil products that the refining industry will focus on in the coming years.

[0003] Prior to 2020, marine fuel primarily consisted of high-sulfur fuel oil, which produced pollutants such as sulfur oxides, nitrogen oxides, and particulate matter during combustion. To control pollution, the International Maritime Organization (IMO) announced the mandatory implementation of new sulfur emission limits starting January 1, 2020. my country is also currently imposing increasingly stringent requirements on the sulfur content of marine fuel.

[0004] However, it is difficult to directly produce low-sulfur marine fuel with a sulfur content of no more than 0.5% by weight using the current blending components.

[0005] To produce low-sulfur marine fuel, most refineries currently remove sulfur from residue oil through hydrotreating to obtain the blending components for low-sulfur marine fuel. However, because residue hydrotreating units are high-pressure hydrotreating units, their investment is large and operating costs are high, resulting in high production costs for low-sulfur marine fuel.

[0006] In addition, the viscosity of residual oil is significantly reduced after hydrotreating, making it difficult to produce high-viscosity (RMG) marine fuel via the residual oil hydrotreating route.

[0007] After hydrotreating, high-sulfur residual oil can be used to produce low-sulfur marine fuel or blending components for low-sulfur marine fuel. For example, CN112300833A discloses a method for producing low-sulfur residual marine fuel. This method involves sequentially loading a hydrotreating protective catalyst, a hydrodemetallization catalyst, and a hydrodemetallization desulfurization protective agent along the stream flow direction in a residual oil hydrotreating unit. This method exhibits good hydrotreating activity and better reaction stability, enabling long-term production of high-quality low-sulfur marine fuel.

[0008] Catalytic slurry oil is rich in polycyclic aromatic hydrocarbons, with high carbon content and low hydrogen content. After desolidification and desulfurization pretreatment, it can be used as a blending component for low-sulfur marine fuel. For example, CN111088068A discloses a method for producing low-sulfur marine fuel oil. In this method, catalytic slurry oil is mixed with a first additive, and after mixing, it is subjected to sedimentation separation to obtain a first material and residue. The first material enters a hydrotreating unit, where a hydrotreating reaction is carried out under the action of a hydrotreating catalyst and hydrogen. The liquid effluent obtained from the reaction enters a clarification unit, and the clarified oil obtained after separation is further subjected to solid-liquid separation to obtain purified slurry oil. The purified slurry oil is mixed with the hydrotreating tail oil of high-sulfur feedstock to obtain low-sulfur marine fuel oil.

[0009] For example, CN101531923A discloses a method for combined catalytic cracking and hydrotreating of inferior feedstock oil. The inferior feedstock oil is hydrotreated, and the resulting hydrotreated residue is then subjected to catalytic cracking to obtain propylene, gasoline, catalytic cracked heavy oil, and other products. The catalytic cracked heavy oil enters the hydrotreating unit, and the hydrotreated catalytic cracked heavy oil is recycled to the catalytic cracking unit for further reaction to obtain the target products propylene and gasoline. This method employs moderate catalytic cracking technology, which can reduce the yield of coke and dry gas during catalytic cracking. Furthermore, this method generates some unconverted catalytic cracked heavy oil. Catalytic cracked heavy oil is also rich in polycyclic aromatic hydrocarbons, but compared to catalytic slurry oil, it has lower viscosity and lower sulfur content, making it easier to remove solids and allowing it to be used as a blending component for low-sulfur marine fuel without desulfurization.

[0010] Most existing technologies achieve desulfurization of residual oil through residual oil hydrotreating units to obtain the main blending components for low-sulfur heavy marine fuel. However, residual oil hydrotreating units have high pressure, large investment, and high operating costs, which increases the production cost of low-sulfur heavy marine fuel. Moreover, most residual oil hydrotreating units are currently matched with downstream catalytic cracking units, resulting in a waste of the processing capacity of the catalytic cracking unit after the production of low-sulfur marine fuel. Summary of the Invention

[0011] The purpose of this invention is to overcome the shortcomings of existing technologies in producing light oil products and low-sulfur marine fuel oil with high yields from inferior residual oil.

[0012] To achieve the above objectives, the present invention provides a method for processing inferior residual oil, the method comprising the following steps:

[0013] (1) In the presence of a catalytic cracking catalyst, inferior residue oil I is subjected to a moderate catalytic cracking reaction to obtain the moderate catalytic cracking reaction product;

[0014] (2) The mild catalytic cracking reaction products are separated to obtain catalytic cracked gasoline, catalytic cracked diesel and catalytic cracked heavy oil;

[0015] (3) In the presence of a selective hydrodesulfurization catalyst, the catalytic cracking heavy oil is subjected to a hydrodesulfurization reaction to obtain the hydrodesulfurization reaction product;

[0016] (4) Separate the hydrodesulfurization reaction products to obtain hydrotreated gasoline and hydrotreated heavy oil that can be blended with the inferior residue oil I to form low-sulfur marine fuel; the mass content of the hydrotreated heavy oil in the low-sulfur marine fuel is 10%-90%;

[0017] In the aforementioned inferior residual oil I, the sulfur content is 0.6%-3.0% by mass, and the density of the inferior residual oil I at 20°C is not greater than 0.97 g / cm³. 3.

[0018] The method for processing inferior residue oil provided by this invention combines catalytic cracking heavy oil hydrotreating with catalytic cracking, which can maximize the production of light oil products and low-sulfur marine fuel oil from inferior residue oil, thereby reducing the production cost of the light oil products and low-sulfur marine fuel oil obtained therefrom.

[0019] In addition, the method for processing inferior residual oil provided by the present invention has the following specific advantages:

[0020] (1) The method provided by the present invention can give full play to the conversion function of the catalytic cracking unit and the desulfurization function of the catalytic cracking heavy oil hydrotreating unit. The process is simple and reasonable and can improve the utilization efficiency of petroleum resources.

[0021] (2) In the method provided by the present invention, the hydrodesulfurization reaction is preferably carried out in the catalytic cracking heavy oil hydrodesulfurization unit, and the selective hydrodesulfurization process can reduce hydrogen consumption.

[0022] (3) The method provided by the present invention can avoid the construction of high pressure residue hydrogenation equipment, save investment and operating costs, and is also more suitable for producing high viscosity low sulfur marine fuel oil. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the process flow of a preferred embodiment of the present invention for processing inferior residual oil.

[0024] Explanation of reference numerals in the attached figures

[0025] 1. Inferior residual oil; I2. Pipelines

[0026] 3. Moderate catalytic cracking unit

[0027] 4. Dry gas 5. Liquefied petroleum gas

[0028] 6. Catalytic cracked gasoline 7. Catalytic cracked diesel

[0029] 8. Catalytic cracking heavy oil 9. Filtration unit

[0030] 10. Filtered catalytic cracking heavy oil 11. Catalytic cracking heavy oil hydrotreating unit

[0031] 12. Hydrodesulfurization reaction products 13. Second separation system

[0032] 14. Gases 15. Hydrogenated gasoline

[0033] 16. Hydrogenated heavy oil 17. Pipeline

[0034] 18. Low-sulfur marine fuel Detailed Implementation

[0035] The endpoints and any values ​​of the ranges 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 endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0036] As mentioned above, the present invention provides a method for processing inferior residual oil, the method comprising the following steps:

[0037] (1) In the presence of a catalytic cracking catalyst, inferior residue oil I is subjected to a moderate catalytic cracking reaction to obtain the moderate catalytic cracking reaction product;

[0038] (2) The mild catalytic cracking reaction products are separated to obtain catalytic cracked gasoline, catalytic cracked diesel and catalytic cracked heavy oil;

[0039] (3) In the presence of a selective hydrodesulfurization catalyst, the catalytic cracking heavy oil is subjected to a hydrodesulfurization reaction to obtain the hydrodesulfurization reaction product;

[0040] (4) Separate the hydrodesulfurization reaction products to obtain hydrotreated gasoline and hydrotreated heavy oil that can be blended with the inferior residue oil I to form low-sulfur marine fuel; the mass content of the hydrotreated heavy oil in the low-sulfur marine fuel is 10%-90%;

[0041] In the aforementioned inferior residual oil I, the sulfur content is 0.6%-3.0% by mass, and the density of the inferior residual oil I at 20°C is not greater than 0.97 g / cm³. 3 .

[0042] Preferably, the density of the inferior residual oil I at 20°C is 0.90-0.97 g / cm³. 3 More preferably, the density of the inferior residual oil I at 20°C is 0.93-0.97 g / cm³. 3 More preferably, the density of the inferior residual oil I at 20°C is 0.936-0.96 g / cm³. 3 .

[0043] In a preferred embodiment, the kinematic viscosity of the inferior residual oil I at 100°C is 50 mmHg. 2 / s -5000mm 2 / s, residual carbon content is 5%-50%, nitrogen content is 0.05%-2.0%, asphaltene content is 0.1%-10.0%, nickel content is 2ppm-200ppm, and vanadium content is 2ppm-200ppm.

[0044] Preferably, in step (1), the conditions for the moderate catalytic cracking reaction are at least satisfied as follows: volume hourly space velocity (VHSV) of 25 h⁻¹. -1 -100h -1 The reaction temperature is 450℃-600℃.

[0045] Preferably, in step (1), the catalytic cracking catalyst is selected from at least one of zeolite, inorganic oxide and clay.

[0046] More preferably, in step (1), the catalytic cracking catalyst is a waste equilibrium catalyst with a cracking activity of not less than 45.

[0047] In this invention, the cracking activity can be measured by the method specified in NB / SH / T 0952-2017.

[0048] Preferably, the mild catalytic cracking reaction is carried out in a mild catalytic cracking unit.

[0049] According to a particularly preferred embodiment, step (1) of the present invention includes: introducing inferior residue oil I into a mild catalytic cracking unit in the presence of a catalytic cracking catalyst to carry out a mild catalytic cracking reaction, thereby obtaining mild catalytic cracking reaction products.

[0050] The method of the present invention may further include: preheating the inferior residue oil I before introducing it into the mild catalytic cracking unit to obtain preheated inferior residue oil I; and then introducing the preheated inferior residue oil I into the mild catalytic cracking unit to carry out the mild catalytic cracking reaction.

[0051] This invention does not impose any special requirements on the specific conditions of the preheating treatment. Those skilled in the art can perform the preheating operation in conjunction with known preheating operations in the art. There are also no special requirements on the temperature of the material after preheating, which those skilled in the art can determine based on their known knowledge.

[0052] For example, the mild catalytic cracking device of the present invention may include a first reaction zone and a second reaction zone arranged sequentially along the liquid phase flow direction. The mild catalytic cracking device does not specifically contain two reaction zones. The main point is that in the mild catalytic cracking device, as the mild catalytic cracking reaction proceeds, the catalytic cracking activity of the catalytic cracking catalyst continuously decreases. As the catalytic cracking activity of the catalytic cracking catalyst continuously decreases, the mass content of the catalytic cracked heavy oil continuously increases, thereby achieving the effect of mild catalytic cracking.

[0053] Preferably, the preheated inferior residue oil I described in this invention is introduced into the mild catalytic cracking unit under the lifting action of steam to react with the catalytic cracking catalyst contained therein. Through this contact, a macromolecular cracking reaction is carried out to remove at least one impurity from the inferior residue oil I, including metals, sulfur, and nitrogen.

[0054] Preferably, in this invention, after the preheated inferior residue oil I undergoes the macromolecular cracking reaction, the resulting reaction stream is further subjected to cracking, hydrogen transfer, and isomerization reactions.

[0055] Preferably, in step (2), the separation conditions are controlled such that the cutting point between the catalytic cracked diesel and the catalytic cracked heavy oil is 260°C-380°C.

[0056] Preferably, at least one of dry gas and liquefied gas can also be obtained in the separation of step (2) of the present invention.

[0057] According to a particularly preferred embodiment, in step (2), the separation conditions are controlled to obtain dry gas, propylene, propane, C4 hydrocarbons, the catalytic cracked gasoline, the catalytic cracked diesel, and the catalytic cracked heavy oil.

[0058] Preferably, in step (3), the conditions of the hydrodesulfurization reaction are such that the mass content of sulfur in the obtained hydrodesulfurization reaction product is 0.001%-0.50%, the mass content of silicon is 0ppm-50ppm, the mass content of aluminum is 0ppm-50ppm, and the density of the hydrodesulfurization reaction product at 20°C is 0.85g / cm³. 3 -0.95g / cm 3 The kinematic viscosity at 50°C is 2 mm. 2 / s-200mm 2 / s.

[0059] More preferably, the conditions for the hydrodesulfurization reaction are at least: a reaction temperature of 330℃-430℃, a reaction pressure of 0.5MPa-8.0MPa, and a volume hourly space velocity of 0.1h. -1 -5.0h -1 The hydrogen-to-oil volume ratio is 200-2000:1.

[0060] Preferably, in step (3), the selective hydrodesulfurization catalyst contains a support and an active metal component supported on the support, wherein the active metal element in the active metal component is a combination of at least one group VIB metal element and at least one group VIII metal element; the support is selected from at least one of alumina, silica and amorphous silica-alumina.

[0061] In a preferred embodiment, the content of the active metal component, calculated as oxide, in the selective hydrodesulfurization catalyst is 0.05-0.30% by weight, and the content of the support is 0.70-0.95% by weight, based on the total weight of the selective hydrodesulfurization catalyst.

[0062] More preferably, in the selective hydrodesulfurization catalyst, the active metal elements are molybdenum and cobalt, and the support is alumina.

[0063] According to a particularly preferred embodiment, in the selective hydrodesulfurization catalyst, the active metal elements are molybdenum and cobalt, the support is alumina, and based on the total weight of the selective hydrodesulfurization catalyst, the content of molybdenum, calculated as oxide, is 0.05-0.20% by weight, the content of cobalt, calculated as oxide, is 0.05-0.20% by weight, and the content of alumina as support is 0.60-0.90% by weight.

[0064] Preferably, in step (3), the selective hydrodesulfurization catalyst is in the shape of a gear with a central hole or a butterfly extrusion strip.

[0065] Preferably, in the hydrodesulfurization reaction, a hydroprotective catalyst and a hydrotransition catalyst are sequentially loaded upstream of the selective hydrodesulfurization catalyst. That is, preferably, in the hydrodesulfurization reaction, the catalytic cracking heavy oil is contacted sequentially with the hydroprotective catalyst, the hydrotransition catalyst, and the selective hydrodesulfurization catalyst.

[0066] According to a preferred embodiment, in the hydrodesulfurization reaction, the loading volume ratio of the hydroprotective catalyst, the hydrotransition catalyst, and the selective hydrodesulfurization catalyst is 0.05-0.10:0.05-0.40:1.

[0067] This invention does not impose any particular requirements on the specific types of the hydrogenation protection catalyst and the hydrogenation transition catalyst. Those skilled in the art can use various hydrogenation protection catalysts and hydrogenation transition catalysts known in the art in this invention. The examples provided in this invention illustrate specific types of hydrogenation protection catalysts and hydrogenation transition catalysts, which should not be construed as limiting the invention.

[0068] Preferably, in step (3), the selective hydrodesulfurization catalyst has a desulfurization selectivity of more than 90%, and the desulfurization selectivity = (sulfur content in inferior residue oil I - sulfur content in hydrodesulfurization reaction product) * (hydrogen content in hydrodesulfurization reaction product - hydrogen content in inferior residue oil I) / sulfur content in inferior residue oil I * 100%.

[0069] More preferably, the selective hydrodesulfurization catalyst has a desulfurization selectivity of over 95%.

[0070] Preferably, in step (3), the method further includes: before carrying out the hydrodesulfurization reaction, filtering the catalytic cracking heavy oil to obtain pretreated catalytic cracking heavy oil with a solid content of less than 100 ppm, and then carrying out the hydrodesulfurization reaction on the pretreated catalytic cracking heavy oil.

[0071] This invention does not impose special requirements on the equipment and processes used for the filtration process; any commercially available filtration technology can be employed. However, preferably, to achieve better filtration results, the filtration process utilizes a flexible desolvation technique.

[0072] Preferably, the hydrodesulfurization reaction is carried out in a catalytic cracking heavy oil hydrotreating unit.

[0073] According to a particularly preferred embodiment, step (3) of the present invention includes: introducing the catalytic cracking heavy oil into a catalytic cracking heavy oil hydrotreating unit in the presence of a selective hydrodesulfurization catalyst to carry out a hydrodesulfurization reaction, thereby obtaining a hydrodesulfurization reaction product.

[0074] In a preferred embodiment, the catalytic cracking heavy oil hydrotreating unit adopts a pressure-switching operation mode. During the first 6 months of unit operation, the first reaction pressure of the unit is 3MPa-6MPa to improve the selectivity of hydrodesulfurization. After 6 months of unit operation, as catalyst coking increases and hydrodesulfurization selectivity improves, the second reaction pressure of the unit is adjusted to 6MPa-8MPa to reduce the catalyst coking rate and further extend the unit's operating cycle.

[0075] In a further preferred embodiment, the second reaction pressure is higher than the first reaction pressure.

[0076] Preferably, in step (4), the separation conditions are controlled such that the cutting point between the hydrogenated gasoline and the hydrogenated heavy oil is 160°C-210°C.

[0077] Preferably, in step (4), the separation conditions are controlled such that the final boiling point of the hydrotreated heavy oil is 240°C-380°C.

[0078] Preferably, in step (4), the method can also obtain gas by controlling the separation conditions.

[0079] Preferably, in step (4), the mass content of the hydrogenated heavy oil in the low-sulfur marine fuel is 30%-50%.

[0080] The following combination Figure 1Preferred embodiments of the present invention will be described in detail, but are not intended to limit the invention.

[0081] exist Figure 1 In this invention, the method includes:

[0082] S1: In the presence of a catalytic cracking catalyst, a portion of the inferior residue oil I1 is preheated to obtain preheated inferior residue oil I. The preheated inferior residue oil I is then introduced via pipeline 2 into a mild catalytic cracking unit 3 containing a mild catalytic cracking device and a first separation system for mild catalytic cracking reaction and separation. Specifically, the preheated inferior residue oil I undergoes a mild catalytic cracking reaction in the mild catalytic cracking device to obtain mild catalytic cracking reaction products. Then, the mild catalytic cracking reaction products are introduced into the first separation system for separation to obtain dry gas 4, liquefied petroleum gas 5, catalytic cracked gasoline 6, catalytic cracked diesel 7, and catalytic cracked heavy oil 8, respectively.

[0083] S2: The catalytic cracking heavy oil 8 is introduced into the filtration device 9 for filtration treatment, and the solid particles are filtered out to obtain the filtered catalytic cracking heavy oil 10; in the presence of the hydroprotection catalyst, the hydrotransition catalyst, and the selective hydrodesulfurization catalyst, the filtered catalytic cracking heavy oil 10 is introduced into the catalytic cracking heavy oil hydrotreating device 11 for hydrodesulfurization reaction to obtain the hydrodesulfurization reaction product 12;

[0084] S3: The hydrodesulfurization reaction product 12 is introduced into the second separation system 13 for separation to obtain gas 14, hydrotreated gasoline 15 and hydrotreated heavy oil 16 respectively.

[0085] S4: The hydrotreated heavy oil 16 is blended with another portion of inferior residue oil I from pipeline 17 to serve as low-sulfur marine fuel 18.

[0086] The present invention will be described in detail below through examples, but this does not limit the invention. In the following examples, unless otherwise specified, the raw materials used are all commercially available products.

[0087] Unless otherwise specified, the following examples all use Figure 1 The process flow shown is as described below, and the process flow in each example will not be described in detail in the following embodiments.

[0088] The inferior residue feedstocks used in the example are residue oil A and residue oil B, whose main properties are shown in Table 1. The catalysts with the following grades RG-202, RDM-33B, and RFS-100 are all produced by Changling Catalyst Plant of Sinopec Catalyst Branch, and their main properties are shown in Table 2.

[0089] The catalytic cracking catalyst used in the following examples is MLC-500, produced by Sinopec Catalyst Changling Branch.

[0090] Table 1

[0091]

[0092] Table 2

[0093]

[0094] Example 1

[0095] S1: In the presence of a catalytic cracking catalyst, a portion of the inferior residue oil I is preheated to obtain preheated inferior residue oil I; under the lifting action of steam, the preheated inferior residue oil I is introduced via pipeline into a mild catalytic cracking unit containing a mild catalytic cracking device and a first separation system for mild catalytic cracking reaction and separation in sequence; specifically, the preheated inferior residue oil I is contacted with the catalytic cracking catalyst in the mild catalytic cracking device (fluidized bed, the same below) to carry out a mild catalytic cracking reaction to obtain mild catalytic cracking reaction products; then the mild catalytic cracking reaction products are introduced into the first separation system for separation to obtain dry gas, liquefied petroleum gas, catalytic cracked gasoline, catalytic cracked diesel, and catalytic cracked heavy oil, respectively;

[0096] The conditions for the moderate catalytic cracking reaction in the moderate catalytic cracking unit are: a volume hourly space velocity (VHSV) of 30 h⁻¹. -1 The reaction temperature is 520℃;

[0097] The initial boiling point of the catalytic cracking heavy oil is 280°C;

[0098] S2: The catalytic cracking heavy oil is introduced into a filtration device for filtration treatment. After filtering out solid particles, the filtered catalytic cracking heavy oil with properties as shown in Table 3 is obtained. In the presence of a hydroprotective catalyst, a hydrotransition catalyst, and a selective hydrodesulfurization catalyst, the filtered catalytic cracking heavy oil is introduced into a catalytic cracking heavy oil hydrotreating unit for hydrodesulfurization reaction to obtain hydrodesulfurization reaction products.

[0099] In the hydrodesulfurization reaction, the loading volume ratio of the hydroprotective catalyst, the hydrotransition catalyst, and the selective hydrodesulfurization catalyst is 6:10:100.

[0100] The conditions for the catalytic cracking hydrodesulfurization reaction are shown in Table 3;

[0101] S3: The hydrodesulfurization reaction products are introduced into the second separation system for separation to obtain gas, hydrotreated gasoline and hydrotreated heavy oil, respectively.

[0102] The hydrogenated gasoline has a distillation range of 30℃-170℃, and the hydrogenated heavy oil has an initial boiling point of 170℃.

[0103] Other properties of the hydrotreated heavy oil are listed in Table 3;

[0104] S4: The hydrotreated heavy oil is blended with another portion of inferior residue oil I from the pipeline to serve as a low-sulfur ship combustion device. Specific property parameters are shown in Table 3.

[0105] Example 2

[0106] This embodiment uses the same process as Embodiment 1, except that the inferior residue oil I used in this embodiment is residue oil B, and the process parameters are different.

[0107] Specifically, the main operating conditions and main product properties of the catalytic cracking heavy oil hydrotreating unit in this embodiment are shown in Table 3.

[0108] Table 3

[0109]

[0110] As shown in Table 3, the method of the present invention can produce high-viscosity, low-sulfur marine fuel. The blended low-sulfur marine fuel meets all the performance requirements of RMG380 (RMG380 marine fuel specifications are listed in Table 3). Specifically, the low-sulfur marine fuels obtained in Examples 1 and 2 have a sulfur content of 0.49% and a viscosity (50°C) of 371 mm⁻¹. 2 / s and 361mm 2 / s.

[0111] Example 3

[0112] This embodiment uses the same process flow as Example 2. The difference is that the catalytic cracking catalyst used in this embodiment is a waste equilibrium catalyst from the catalytic cracking unit, and its cracking activity is 55.

[0113] The remaining parameters, conditions, and results of this embodiment are shown in Table 3.

[0114] Using the method of Example 3, the low-sulfur marine fuel obtained through blending met all the performance requirements of RMG380 (RMG380 marine fuel specifications are listed in Table 3). Specifically, the low-sulfur marine fuel obtained in Example 3 had a sulfur content of 0.49% by mass and a viscosity (50°C) of 355 mm. 2 / s.

[0115] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for processing inferior residual oil, characterized in that, The method includes the following steps: (1) subjecting the inferior residue I to a mild catalytic cracking reaction in the presence of a catalytic cracking catalyst to obtain a mild catalytic cracking reaction product; the mild catalytic cracking reaction is at least under the following conditions: a volume space velocity of 25 h -1 -100 h -1 -1, and a reaction temperature of 450°C-600°C; (2) Separate the mild catalytic cracking reaction products to obtain catalytic cracking gasoline, catalytic cracking diesel and catalytic cracking heavy oil; control the separation conditions so that the cutting point between the catalytic cracking diesel and the catalytic cracking heavy oil is 260℃-380℃; (3) The catalytic cracking heavy oil is first filtered to obtain pretreated catalytic cracking heavy oil with a solid content of less than 100 ppm. In the presence of a selective hydrodesulfurization catalyst, the pretreated catalytic cracking heavy oil is subjected to a hydrodesulfurization reaction to obtain a hydrodesulfurization reaction product. The hydrodesulfurization reaction is performed under conditions such that the mass content of sulfur in the obtained hydrodesulfurization reaction product is 0.001%-0.5%, the mass content of silicon is 0 ppm-50 ppm, the mass content of aluminum is 0 ppm-50 ppm, and the density of the hydrodesulfurization reaction product at 20°C is 0.85 g / cm³. 3 -0.95g / cm 3 The kinematic viscosity at 50°C is 2 mm. 2 / s-200mm 2 / s; upstream of the selective hydrodesulfurization catalyst, a hydroprotective catalyst and a hydrotransition catalyst are sequentially loaded; in the hydrodesulfurization reaction, the loading volume ratio of the hydroprotective catalyst, the hydrotransition catalyst, and the selective hydrodesulfurization catalyst is 0.05-0.10:0.05-0.40:1; the desulfurization selectivity of the selective hydrodesulfurization catalyst is higher than 95%, and the desulfurization selectivity = (sulfur content in inferior residue oil I - sulfur content in hydrodesulfurization reaction product) * (hydrogen content in hydrodesulfurization reaction product - hydrogen content in inferior residue oil I) / sulfur content in inferior residue oil I * 100%; (4) Separate the hydrodesulfurization reaction products to obtain hydrotreated gasoline and hydrotreated heavy oil; control the separation conditions so that the cutting point between the hydrotreated gasoline and the hydrotreated heavy oil is 160℃-210℃ and the final boiling point of the hydrotreated heavy oil is 240℃-380℃. The hydrotreated heavy oil and inferior residue oil I are blended to form low-sulfur marine fuel; the mass content of the hydrotreated heavy oil in the low-sulfur marine fuel is 30%-50%; In the aforementioned inferior residual oil I, the sulfur content is 0.6%-3.0% by mass, and the density of the inferior residual oil I at 20°C is not greater than 0.97 g / cm³. 3 The kinematic viscosity of the inferior residual oil I at 100°C is 3500 mm. 2 / s-5000mm 2 / s.

2. The method according to claim 1, wherein, In step (1), the catalytic cracking catalyst is selected from at least one of zeolite, inorganic oxide and clay.

3. The method according to claim 1 or 2, wherein, In step (1), the catalytic cracking catalyst is a waste equilibrium catalyst with a cracking activity of not less than 45.

4. The method according to claim 1 or 2, wherein, In step (3), the conditions for the hydrodesulfurization reaction must at least meet the following requirements: reaction temperature of 330℃-430℃, reaction pressure of 0.5MPa-8.0MPa, and volume hourly space velocity of 0.1h. -1 -5.0h -1 The hydrogen-to-oil volume ratio is 200-2000:

1.

5. The method according to claim 1 or 2, wherein, In step (3), the selective hydrodesulfurization catalyst contains a support and an active metal component supported on the support. The active metal element in the active metal component is a combination of at least one group VIB metal element and at least one group VIII metal element. The support is selected from at least one of alumina, silica and amorphous silica-alumina.

6. The method according to claim 5, wherein, In step (3), the active metal elements in the selective hydrodesulfurization catalyst are molybdenum and cobalt, and the support is alumina.

7. The method according to claim 1, wherein, In step (3), the filtration process is carried out using flexible desolidification technology.

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