CN110734783A - Processing method of inferior heavy oil - Google Patents

Abstract

The invention discloses a processing method of poor heavy oils, which comprises the steps of deasphalting an inferior heavy oil raw material by a solvent to obtain deasphalted oil and deoiled asphalt, mixing the deoiled asphalt with hydrocarbon oil containing monocyclic aromatic hydrocarbon to be used as hydrogenation feed, carrying out hydrogenation treatment in the presence of hydrogen to obtain a th hydrogenation treatment product, mixing the th hydrogenation treatment product with the deasphalted oil to carry out second hydrogenation treatment to obtain a second hydrogenation treatment product.

Description

A kind of processing method of inferior heavy oil

technical field

The invention relates to a processing method of inferior heavy oil, in particular to a processing method of inferior heavy oil with high metal impurity content and high residual carbon content.

Background technique

With the increasing weight and quality of oil, it brings more and more difficulties to oil processing. Heavy oil contains a large amount of metal impurities such as Ni, V, etc. Most of the metal impurities exist in asphaltenes, which are difficult to remove.

The processing technology is usually selected according to the content of metal impurities in the heavy oil. When the metal impurity V+Ni content is below 200 μg/g and the residual carbon value is below 15%, the fixed bed process can be used. The process of the fixed bed is simple, the investment is small, and the maintenance is easy. It is the first choice for the hydrogenation process of heavy oil. When the metal impurity V+Ni content is more than 200μg/g and the residual carbon value is more than 15%, the fluidized bed or suspended bed process is generally used. However, the fluidized bed process is extremely complicated, the equipment investment is large, and it is difficult to maintain, which is an important reason for the difficulty in popularizing the process. The suspended bed process is also relatively complex, and there are many problems in the process, which is not easy to promote.

Solvent deasphalting is the extraction of gums and asphaltenes from heavy oil to produce deasphalted oil and deoiled asphalt. At present, the main purpose of solvent deasphalting in processing heavy oil is to obtain deasphalted oil, which can be used as a raw material for catalytic cracking, fixed bed hydroprocessing and other processes. However, for deoiled asphalt, since its main component is asphaltene, the basic structural unit of asphaltene is a fused aromatic ring system composed of multiple aromatic rings, surrounded by several naphthenic rings and aromatic rings, and the ring With several alkyl side chains of different lengths, there are S, N, O hetero atom groups in the aromatic nucleus structure, and also contains complex V, Ni and other metals. Asphaltene is composed of several such structural units connected by bridge bonds formed by alkyl groups or heteroatoms, and exists in an associative state. It is the main coking precursor in the hydrogenation reaction. Therefore, it is limited by the existing hydrogenation process. , it is difficult to efficiently convert asphaltene components into light fuel oil. Therefore, the ability to cost-effectively convert high asphaltene feedstocks to light fuel oils is a challenge in the art.

CN200910162163.9 discloses a method for processing inferior crude oil by combined process. The method is to first deasphalt the inferior crude oil by solvent to obtain deasphalted oil; the deasphalted oil enters the first reaction zone of the catalytic conversion reactor after preheating, and the oil and gas generated by the reaction and the used catalyst are optionally mixed with the light raw material. After the oil is mixed, it enters the second reaction zone for cracking reaction, hydrogen transfer reaction and isomerization reaction. After liquid-solid separation, the reaction products are further separated into dry gas, liquefied gas, gasoline, diesel oil and catalytic wax oil. The first reaction The reaction conditions of the second reaction zone and the second reaction zone are sufficient to obtain the catalytic wax oil which accounts for 12% to 60% of the raw oil. gasoline. This method mainly converts deasphalted oil into light fuel oil, and does not involve the subsequent processing of deoiled asphalt.

CN 201110352418.5 discloses a processing method of inferior heavy oil. The method comprises: (1) entering the raw material of inferior heavy oil into a solvent deasphalting unit to obtain deasphalted oil and deoiled asphalt; (2) entering the deoiled asphalt obtained in step (1) into a fluidized bed hydrotreating unit, where hydrogen and boiling In the presence of the bed hydrotreating catalyst, the ebullated bed hydrotreating is carried out; (3) the ebullating bed hydrotreating reaction effluent obtained in step (2) is mixed with the deasphalted oil into the fixed bed hydrotreating device, and the hydrogen and the fixed bed are mixed with the hydrotreating oil. In the presence of the bed hydrotreating catalyst, the fixed bed hydrotreating is carried out, and the generated oil obtained from the reaction effluent of the fixed bed hydrotreating is used as the raw material of the catalytic cracking unit. The fluidized bed process is complex, the equipment is expensive, and the investment in fixed assets is large.

CN200410050788.3 discloses a treatment method for inferior heavy oil or residual oil. The method includes: the heavy oil or residual oil raw material first enters a solvent extraction device; the obtained deasphalted oil enters a fixed bed hydrotreating device for hydrotreating; the obtained hydrogenated tail oil enters a catalytic cracking device, wherein the obtained oil slurry and The deoiled asphalt enters the suspended bed hydrogenation unit together, and the product is separated to obtain light fractions and unconverted tail oil, wherein the unconverted tail oil is recycled to the solvent extraction unit. The method can also use the light naphtha produced by the suspended bed hydrogenation as the solvent of the solvent extraction device. The suspended bed hydrogenation catalyst is a homogeneous catalyst, and it is easy to make the coke adsorbed on the active center of the catalyst, so that it is quickly deactivated.

SUMMARY OF THE INVENTION

Aiming at the deficiencies in the prior art, the present invention provides a processing method of inferior heavy oil. The method of the invention can convert the whole fraction of inferior heavy oil into light fuel oil and heavy fuel oil, and the heavy fuel oil has good properties and long operation period.

The processing method of inferior heavy oil provided by the invention comprises:

(1) Deasphalted oil and deoiled asphalt are obtained by solvent deasphalting of inferior heavy oil raw materials;

(2), the deoiled pitch obtained in step (1) is mixed with the hydrocarbon oil containing monocyclic aromatic hydrocarbons as hydrogenation feed, and the first hydroprocessing is carried out in the presence of hydrogen to obtain the first hydroprocessing product;

(3), mixing the first hydrotreated product obtained in step (2) with the deasphalted oil obtained in step (1) to carry out a second hydrotreatment to obtain a second hydrotreated product.

The inferior heavy oil described in step (1) is a heavy oil containing asphaltene, which can be derived from petroleum hydrocarbons and/or other mineral oils, wherein the petroleum hydrocarbons can be derived from residual oil and/or crude oil, and wherein the residual oil can be selected from vacuum residues One or more of oil and atmospheric residual oil, and crude oil can be selected from heavy oil. Other mineral oils are one or more of coal liquefied oil, oil sands oil, and shale oil.

In the inferior heavy oil, the content of metal impurities V and Ni can be more than 150 μg/g, and can also be more than 200 μg/g, generally can be 150-900 μg/g, and can also be 200 μg/g-900 μg/g. The weight content of the powder can be more than 10%, and it can also be more than 15%, generally it can be 10% to 28%, and it can also be 15% to 28%. In the inferior heavy oil, the weight content of sulfur may be more than 3%, more than 4%, and more than 5%.

The hydrogenation feed in step (2) may also include pitch components from other sources, such as one or more of coal tar pitch, straight-run pitch, and natural pitch.

The solvent deasphalting described in step (1) refers to the process of using inferior heavy oil as raw material, mainly using solvent to extract asphaltene, and recycling the solvent.

In the solvent deasphalting of step (1), the solvent used is at least one of alkane, wax and gasoline, wherein the carbon number of the alkane is 3-22, preferably 3-12, and it can be a straight-chain alkane, It can also be a branched alkane, and the alkane can be selected from at least one of propane, butane, pentane, hexane, heptane, octane, and decane. The number of carbon atoms of the wax is preferably 40 or less, and may be derived from at least one of Fischer-Tropsch synthesis, isomerization dewaxing, synthetic wax, polyethylene wax, solvent dewaxing, and polymer wax. The gasoline can be selected from low-boiling gasoline, such as gasoline with a dry point below 120°C. The extraction equipment used for solvent deasphalting can be carried out with conventional extraction equipment, such as packed extraction column, sieve tray extraction column or rotating disk extraction column. The solvent in solvent deasphalting can be recovered by conventional methods such as distillation, and the recovered solvent can be recycled.

In the solvent deasphalting of step (1), the volume ratio of the solvent to the raw material of the inferior heavy oil is (3-13):1, preferably (3-8):1.

In step (1), the solvent deasphalting is carried out in an extraction tower, and the pressure and temperature at the top of the extraction tower are as follows: the pressure at the top of the tower can be 2.0～4.5MPa, preferably 2.5～3.9MPa, and the temperature at the top of the tower is 50～90 ℃, Preferably it is 54-82 degreeC.

In step (1), the feeding temperature of the solvent can be 30-80°C, and the feeding temperature of the inferior heavy oil can be 120-150°C.

The described hydrocarbon oil containing monocyclic aromatic hydrocarbons in step (2), wherein the monocyclic aromatic hydrocarbons can be at least one of benzene and alkylbenzene, wherein the carbon number of the alkylbenzene is 7 to 12, preferably the carbon number is 7 ~9, and the alkyl group is selected from 1 to 3, which can be a straight-chain alkyl group or a branched-chain alkyl group, such as one of benzene, toluene, ethylbenzene, p-xylene, m-xylene, and mesitylene. One or more, the mass content of monocyclic aromatic hydrocarbons in the hydrocarbon oil containing monocyclic aromatic hydrocarbons is 40%-100%, preferably 50%-100%, more preferably 85%-100%. The hydrocarbon oil containing monocyclic aromatic hydrocarbons can be derived from the heavy components of reformate gasoline.

The volume ratio of the monocyclic aromatic hydrocarbon-containing hydrocarbon oil to the deoiled asphalt in step (2) is 1-10:1, preferably 2-9:1.

The mass content of monocyclic aromatic hydrocarbons in the hydrocarbon oil containing monocyclic aromatic hydrocarbons in step (2) is more than 85%, and the volume ratio of the hydrocarbon oil containing monocyclic aromatic hydrocarbons to the deoiled asphalt is 1-6:1, preferably 2- 5:1.

The first hydrotreating catalyst used in the first hydrotreating described in step (2) includes a carrier and a hydrogenation active metal component. Based on the weight of the catalyst, the content of the hydrogenation active metal is 38% to 70%. , preferably 40% to 65%. In the first hydrotreating catalyst, the carrier adopts an alumina-based carrier, the hydrogenation active metal component adopts the metal component of Group VIB and/or Group VIII, and the metal of Group VIB is at least one of W and Mo. , the Group VIII metal is at least one of Ni and Co, more preferably the ratio of the weight content of the Group VIB metal in terms of oxide to the weight content of Group VIII metal in terms of oxide is 1 to 8:1, preferably 1 to 6:1, more preferably 3 to 6:1.

The properties of the first hydrotreating catalyst are as follows: the bulk density is 0.45-0.64 g/cm ³ , the lateral pressure strength is greater than 10 N/mm, generally 10-80 N/mm, and the pore volume is 0.5-1.2 mL/g, preferably It is 0.7 to 1.1 mL/g, the specific surface area is 60 to 200 m ² /g, and the pore distribution is as follows: the pore volume occupied by pores with a pore diameter of 20 nm or less is 30% or less of the total pore volume, preferably 10% or less. The pore volume occupied by pores with a diameter of 20 to 100 nm is 55% to 80% of the total pore volume, and the pore volume occupied by pores with a diameter of 100 nm or more is less than 40% of the total pore volume, preferably 5% to 40%. %.

The shape and particle size of the first hydrotreating catalyst can be the shape and size used for the conventional fixed bed and residue hydrotreating catalyst, for example, the shape can be a strip, a sphere, a clover, a four-leaf clover or a pentadentate ball. , the particle size is 2 ~ 8mm.

The first hydrotreating catalyst of the present invention can be prepared by conventional methods, such as pore-enlarging agent method, molten salt supersolubilizing micelle method, etc. for the carrier, and impregnation method, co-precipitation method, etc. for the supported active metal.

The operating conditions used in the first hydrotreating described in step (2) are as follows: the reaction pressure is 10.0-17.5 MPa, the liquid hourly volume space velocity is 0.1-2.0 h ^-1 , and the volume ratio of hydrogen to oil is 380-1000:1 , the reaction temperature is 350～411℃, and the preferred operating conditions are as follows: the reaction pressure is 12.0～17.0MPa, the liquid hourly volume space velocity is 0.1～0.6h ^-1 , the volume ratio of hydrogen to oil is 500～1000:1, and the reaction temperature is 375～390℃.

The second hydrotreating catalyst used in the second hydrotreating in the step (3) can be a conventional hydrotreating catalyst, which is mainly used for removing impurities such as sulfur, such as a residue hydrodesulfurization catalyst and the like. The second hydroprocessing catalyst includes a support component and a hydrogenation active metal component. The carrier generally adopts an alumina-based carrier. The hydrogenation active metal component is generally a Group VIB metal and/or a Group VIII metal, the Group VIB metal is generally selected from at least one of Mo and W, and the Group VIII metal is generally selected from Co and Ni at least one of them. Based on the weight of the catalyst, the content of the hydrogenation active metal oxide is 20% to 35%, preferably, the ratio of the metal of Group VIB to the metal of Group VIII in terms of oxide is 1 to 6:1 . The properties of the second hydrotreating catalyst are as follows: the pore volume is 0.2-0.6 mL/g, the specific surface area is 100-250 m ² /g, and the bulk density is 0.65-0.95 g/mL.

The operating conditions of the second hydrotreating described in step (3) are as follows: the reaction pressure is 5-10 MPa, the liquid hourly volume space velocity is 0.5-2.0 h ^-1 , the volume ratio of hydrogen to oil is 500-1000:1, the reaction temperature It is 350～390 ℃.

The shape and particle size of the second hydrotreating catalyst can be the shape and size used for the conventional fixed bed and residue hydrotreating catalyst, for example, the shape can be a strip, a sphere, a clover, a four-leaf clover or a pentadentate ball. , the particle size is 2 ~ 8mm.

In the second hydroprocessing product described in step (3), the sulfur content is below 0.5 wt%, the carbon residue value is below 5 wt%, and the content of metal impurities (calculated in terms of Ni and V content) is below 40 μg/g.

The second hydroprocessing product obtained in step (3) is separated to obtain liquid light hydrocarbons, gasoline, diesel oil and hydrogenated heavy distillate oil. Among them, hydrogenated heavy distillate oil meets the requirements of marine fuel and can be used as marine fuel.

The gas phase product obtained by the separation of the second hydroprocessing product obtained in step (3) can remove H ₂ S and NH ₃ , and the recovered hydrogen can be recycled. Among them, the removal of H ₂ S and NH ₃ generally adopts the lye absorption method.

Compared with the prior art, the method of the present invention has the following advantages:

1. In the method of the present invention, the combination of solvent deasphalting and two-stage hydrotreating process not only can handle inferior heavy oil, but also has a long operation period of the device, the obtained hydrogenated product has good performance, and the hydrogenated heavy fraction can be used as marine fuel oil.

2. In the method of the present invention, the first hydrotreating the deoiled asphalt from the solvent deasphalting unit, and adding the hydrocarbon oil containing monocyclic aromatic hydrocarbons as the mixed hydrogenation feed, under the condition of high pressure hydrogenation, is beneficial to improve the deoiling. The conversion rate of asphalt, especially the reduction of metal content and residual carbon content in the asphaltene component; the deasphalted oil is mixed with the first hydrotreating product to carry out the second hydrotreating, and further mainly removes under medium pressure hydrogenation conditions. The sulfur in it can improve the properties of the product to obtain light fuel oil and heavy fuel oil with excellent properties.

Detailed ways

The technical solutions of the present invention will be described in further detail below with reference to the examples, but the protection scope of the present invention is not limited by the following examples. In the present invention, wt% is a mass fraction.

In the present invention, the specific surface area and pore properties (such as pore volume, average pore diameter, and pore distribution) of the hydrotreating catalyst are analyzed by mercury intrusion.

The properties of the raw materials used in the examples of the present invention and the comparative examples are shown in Table 1.

Table 1 Properties of raw materials

Raw material A Raw material B Density (20℃), g/cm³ 0.985 0.993 Carbon residue, wt% 17.60 19.02 Metal (V+Ni) content, μg/g 243 550 Sulfur, wt% 4.78 5.02 Nitrogen, μg/g 5119 5312

Example 1

Raw material A (see Table 1 for properties) was subjected to solvent deasphalting with an extraction tower, the solvent was butane, the temperature was 70°C, and the volume ratio of butane to vacuum residue raw material was 6:1, stirring uniformly, and precipitation for 20 minutes. The top pressure and temperature of the extraction tower are as follows: the top pressure is 2.8MPa, and the top temperature is 60°C. The feed temperature is 70°C, the feed temperature of the vacuum residue is 120°C, and the deasphalted oil and deoiled asphalt are obtained by separating the upper and lower layers and evaporating the solvent.

The obtained deoiled pitch is mixed with toluene, and the volume ratio of toluene and deoiled pitch is 2:1, and mixed with hydrogen to carry out the first hydrotreating reaction. The first hydrotreating catalyst used in the first hydrotreating is as follows: the hydrogenation active metals are Mo and Ni, in terms of oxides, Mo+Ni is 45wt%, and the weight ratio of Mo:Ni in terms of oxides is 4.5: 1. The carrier is made of alumina, with a strip shape of 3-8 mm. The properties of the catalyst are shown in Table 2. The operating conditions of the first hydrotreating are as follows: the liquid hourly volume space velocity is 0.15h ^-1 , the hydrogen oil volume ratio is 800:1, the reaction temperature is 385°C, and the reaction pressure is 16.5MPa.

The mixture of the first hydrotreating product and the deasphalted oil obtained above was used as the raw material for the second hydrotreating, and the process conditions of the second hydrotreating were as follows: the liquid hourly volumetric space velocity was 1h ^-1 , and the hydrogen oil volume ratio was 800 : 1, the reaction temperature was 385°C, and the reaction pressure was 7.5MPa. The second hydrotreating catalyst uses alumina as a carrier, and the hydrogenation active metals are Mo and Ni, in which, in terms of oxides, Mo+Ni is 35%, and Mo:Ni is 3:1. The properties of the catalyst are as follows: pore volume It is 0.45cm ³ /g, the specific surface area is 120m ² /g, the bulk density is 0.74g/cm ³ , and the strip shape is 3-8mm. The properties of the hydrogenated heavy distillate (boiling point above 350° C.) obtained by the separation of the product obtained by the second hydroprocessing are shown in Table 3. It can be seen from Table 3 that the hydrogenated heavy distillate oil meets the index requirements of marine fuel.

Example 2

Raw material B (see Table 1 for properties) was solvent deasphalted with pentane at a temperature of 70° C., under the condition that the volume ratio of pentane and vacuum residue raw material was 4:1, stirred evenly, and precipitated for 20 minutes. The top pressure and temperature of the extraction tower were as follows: the top pressure was 3.0 MPa, and the top temperature was 80°C. The feed temperature is 50°C, the feed temperature of the vacuum residue is 120°C, and the deasphalted oil and deoiled asphalt are obtained by separating the upper and lower layers and evaporating the solvent.

The obtained deoiled pitch is dissolved in toluene, and the volume ratio of xylene to deoiled pitch is 3:1, and mixed with hydrogen to carry out the first hydrotreating reaction. The first hydrotreating catalyst used in the first hydrotreating is as follows: the active metals for hydrogenation are Mo and Ni, in terms of oxides, Mo+Ni is 50wt%, and the weight ratio of Mo:Ni in terms of oxides is 5: 1. The carrier is made of alumina, with a strip shape of 3-8 mm. The properties of the catalyst are shown in Table 2. The operating conditions of the first hydrotreating are as follows: the liquid hourly volume space velocity is 0.15h ^-1 , the hydrogen oil volume ratio is 800:1, the reaction temperature is 385°C, and the reaction pressure is 17.0MPa.

The mixture of the first hydrotreating product and the deasphalted oil obtained above was used as the raw material for the second hydrotreating, and the process conditions of the second hydrotreating were as follows: the liquid hourly volumetric space velocity was 1h ^-1 , and the hydrogen oil volume ratio was 800 : 1, the reaction temperature was 390°C, and the reaction pressure was 8MPa. The second hydrotreating catalyst is the same as that in Example 1. The properties of the hydrogenated heavy distillate (boiling point above 350° C.) obtained by the separation of the product obtained by the second hydroprocessing are shown in Table 4. It can be seen from Table 4 that the hydrogenated heavy distillate oil meets the index requirements of marine fuel.

Example 3

Raw material A (see Table 1 for properties) was solvent deasphalted with heptane at a temperature of 70° C., under the condition that the volume ratio of heptane to vacuum residue raw material was 4:1, stirred evenly, and precipitated for 40 minutes. The top pressure and temperature of the extraction tower are as follows: the top pressure is 3.2MPa, and the top temperature is 83°C. The feed temperature is 70°C, the feed temperature of the vacuum residue is 120°C, and the deasphalted oil and deoiled asphalt are obtained by separating the upper and lower layers and evaporating the solvent.

The obtained deoiled pitch is dissolved in toluene, and the volume ratio of toluene to deoiled pitch is 2:1, and mixed with hydrogen to carry out the first hydrotreating reaction. The first hydrotreating catalyst used in the first hydrotreating is as follows: the hydrogenation active metals are Mo and Ni, in terms of oxides, Mo+Ni is 48wt%, and the weight ratio of Mo:Ni in terms of oxides is 4: 1. The carrier is made of alumina, with a strip shape of 3-8 mm. The properties of the catalyst are shown in Table 2. The operating conditions of the first hydrotreating are as follows: the liquid hourly volume space velocity is 0.15h ^-1 , the hydrogen oil volume ratio is 1000:1, the reaction temperature is 385°C, and the reaction pressure is 16.5MPa.

The mixture of the first hydrotreating product and the deasphalted oil obtained above was used as the raw material for the second hydrotreating, and the process conditions of the second hydrotreating were as follows: the liquid hourly volumetric space velocity was 1h ^-1 , and the hydrogen oil volume ratio was 750 : 1, the reaction temperature was 385°C, and the reaction pressure was 7.5MPa. The second hydrotreating catalyst is the same as that in Example 1. The properties of the hydrogenated heavy distillate (boiling point above 350° C.) obtained by the separation of the product obtained by the second hydroprocessing are shown in Table 3. It can be seen from Table 3 that the hydrogenated heavy distillate oil meets the index requirements of marine fuel.

Example 4

Raw material B (see Table 1 for properties) was solvent deasphalted with butane at a temperature of 70° C., under the condition that the volume ratio of butane to vacuum residue raw material was 4:1, stirred evenly, and precipitated for 30 minutes. The top pressure and temperature of the extraction tower are as follows: the top pressure is 2.8MPa, and the top temperature is 60°C. The feed temperature is 70°C, the feed temperature of the vacuum residue is 120°C, and the deasphalted oil and deoiled asphalt are obtained by separating the upper and lower layers and evaporating the solvent.

The obtained deoiled asphalt is dissolved with mixed xylene, and the volume ratio of the mixed xylene to the deoiled asphalt is 2:1, and mixed with hydrogen to carry out the first hydrotreating reaction. The first hydrotreating catalyst used in the first hydrotreating is as follows: the active metals for hydrogenation are Mo and Ni, in terms of oxides, Mo+Ni is 54wt%, and the weight ratio of Mo:Ni in terms of oxides is 4: 1. The carrier is made of alumina, with a strip shape of 3-8 mm. The properties of the catalyst are shown in Table 2. The operating conditions of the first hydrotreating are as follows: the liquid hourly volume space velocity is 0.15h ^-1 , the hydrogen oil volume ratio is 800:1, the reaction temperature is 385°C, and the reaction pressure is 17.0MPa.

The mixture of the first hydrotreating product and the deasphalted oil obtained above was used as the raw material for the second hydrotreating, and the process conditions of the second hydrotreating were as follows: the liquid hourly volumetric space velocity was 1h ^-1 , and the hydrogen oil volume ratio was 800 : 1, the reaction temperature was 387°C, and the reaction pressure was 8MPa. The second hydrotreating catalyst is the same as that in Example 1. The properties of the hydrogenated heavy distillate (boiling point above 350° C.) obtained by the separation of the product obtained by the second hydroprocessing are shown in Table 4. It can be seen from Table 4 that the hydrogenated heavy distillate oil meets the index requirements of marine fuel.

Comparative Example 1

The raw material A is directly used as the feed of the residual oil hydrotreating unit, and the first hydrotreating and the second hydrotreating are carried out, wherein the first hydrotreating and the second hydrotreating are the same as in Example 1, and the process is as follows:

Raw material A (see Table 1 for properties) is mixed with hydrogen to carry out the first hydrotreating reaction. The first hydrotreating catalyst and operating conditions are the same as those in Example 1.

The first hydrotreating product is subjected to the second hydrotreating, and the second hydrotreating catalyst and operating conditions are the same as those in Example 1. The properties of the hydrogenated heavy distillate (boiling point above 350° C.) obtained by the separation of the product obtained by the second hydroprocessing are shown in Table 3. It can be seen from Table 3 that the sulfur content in the hydrogenated heavy distillate oil is high and cannot be used as marine fuel. Furthermore, the operation cycle is short.

Comparative Example 2

The raw material B is directly used as the feed of the residual oil hydrotreating unit, and the first hydrotreating and the second hydrotreating are carried out, wherein the first hydrotreating and the second hydrotreating are the same as in Example 3, and the process is as follows:

Raw material B (see Table 1 for properties) is mixed with hydrogen to carry out the first hydrotreating reaction. The first hydrotreating catalyst and operating conditions were the same as in Example 3.

The first hydrotreating product is subjected to the second hydrotreating, and the second hydrotreating catalyst and operating conditions are the same as those in Example 3. The properties of the hydrogenated heavy distillate (boiling point above 350° C.) obtained by the separation of the product obtained by the second hydroprocessing are shown in Table 4. It can be seen from Table 4 that the sulfur content in the hydrogenated heavy distillate is high and cannot be used as marine fuel. Furthermore, the operation cycle is short.

Table 2 Properties of the first hydrotreating catalyst used in the examples and comparative examples of the present invention

catalyst Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Hole volume, cm³/g 0.51 0.58 0.52 0.55 0.51 Specific surface area, m²/g 104 101 106 103 104 Average pore diameter, nm 62 65 60 66 62 Pore distribution, % Below 20nm 9 7 8 9 9 20-100nm 76 75 71 72 76 Above 100nm 15 18 twenty one 19 15 Bulk density, g/cm³ 0.52 0.47 0.54 0.48 0.52 Strength, N/mm twenty four twenty two twenty three twenty two twenty four

Table 3 Properties and yields of hydrogenated heavy distillates

*Deposited metal content is the weight percent of V and Ni deposited in the spent first hydrotreating catalyst to the spent first hydrotreating catalyst, where the amount of V and Ni was determined by plasma emission spectrometry (ICP).

Table 4 Properties and yields of hydrogenated heavy distillates

*Deposited metal content is the weight percent of V and Ni deposited in the spent first hydrotreating catalyst to the spent first hydrotreating catalyst, where the amount of V and Ni was determined by plasma emission spectrometry (ICP).

It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the technical solutions of the present invention; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand: Various changes in form and details of the above embodiments may be made without departing from the spirit and scope defined by the claims and their equivalents.

Claims (10)

1. A processing method of inferior heavy oil, comprising: (1) Deasphalted oil and deoiled asphalt are obtained by solvent deasphalting of inferior heavy oil raw materials; (2), the deoiled pitch obtained in step (1) is mixed with the hydrocarbon oil containing monocyclic aromatic hydrocarbons as hydrogenation feed, and the first hydroprocessing is carried out in the presence of hydrogen to obtain the first hydroprocessing product; (3), mixing the first hydrotreated product obtained in step (2) with the deasphalted oil obtained in step (1) to carry out a second hydrotreatment to obtain a second hydrotreated product. 2. according to the described method of claim 1, it is characterized in that: the described solvent deasphalting of step (1), the solvent that adopts is at least one in alkane, wax, gasoline, and wherein the carbon number of alkane is 3～ 22, preferably 3 to 12; the carbon number of the wax is below 40; the gasoline is selected from gasoline with a dry point below 120°C; Preferably, in step (1), the solvent deasphalting is carried out in an extraction tower, and the volume ratio of the solvent to the low-quality heavy oil raw material is (3-13):1, preferably (3-8):1; the top pressure of the extraction tower and the temperature are as follows: the pressure at the top of the tower is 2.0～4.5MPa, preferably 2.5～3.9MPa, the temperature at the top of the tower is 50～90 ℃, preferably 54～82 ℃; in step (1), the feed temperature of the solvent is 30～90 ℃ 80 ℃, the feed temperature of inferior heavy oil is 120-150 ℃. 3. according to the described method of claim 1, it is characterized in that: the described hydrocarbon oil of step (2) contains monocyclic aromatic hydrocarbon, wherein monocyclic aromatic hydrocarbon is at least one in benzene, alkylbenzene, wherein alkylbenzene The carbon number is 7 to 12, preferably the carbon number is 7 to 9, more preferably one or more of benzene, toluene, ethylbenzene, p-xylene, m-xylene, and mesitylene; Preferably, the mass content of monocyclic aromatic hydrocarbons in the hydrocarbon oil containing monocyclic aromatic hydrocarbons in step (2) is 40% to 100%, preferably 50% to 100%, and more preferably 85% to 100%. The volume ratio of aromatic hydrocarbon oil to deoiled asphalt is 1-10:1; Preferably, the mass content of monocyclic aromatic hydrocarbons in the hydrocarbon oil containing monocyclic aromatic hydrocarbons in step (2) is more than 85%, and the volume ratio of the hydrocarbon oil containing monocyclic aromatic hydrocarbons to the deoiled asphalt is 1 to 6:1, preferably It is 2 to 5:1. 4. The method according to claim 1, characterized in that: the first hydrotreating catalyst used in the first hydrotreating described in step (2) comprises a carrier and a hydrogenation active metal component, and the weight of the catalyst is based on the weight of the catalyst. As a benchmark, the content of hydrogenation active metal is 38% to 70%, preferably 40% to 65%; the carrier adopts alumina-based carrier, and the hydrogenation active metal component adopts Group VIB and/or Group VIII metal component , the metal of Group VIB is at least one of W and Mo, the metal of Group VIII is at least one of Ni and Co, and the metal of Group VIB is at least one of oxides and the metals of Group VIII are more preferably oxides. The weight content ratio is 1 to 8:1, preferably 1 to 6:1, and more preferably 3 to 6:1. 5. The method according to claim 1 or 4, wherein the properties of the first hydrotreating catalyst used in the first hydrotreating described in step (2) are as follows: the bulk density is 0.45 to 0.64 g/cm ^3. The lateral pressure strength is greater than 10N/mm, generally 10-80N/mm, the pore volume is 0.5-1.2mL/g, preferably 0.7-1.1mL/g, the specific surface area is 60-200m ² /g, and the pore distribution is as follows : The pore volume occupied by pores with a pore diameter of 20 nm or less is 30% or less of the total pore volume, preferably 10% or less, and the pore volume occupied by pores with a pore diameter of 20 to 100 nm is 55% to 80% of the total pore volume. %, the pore volume occupied by pores with a pore diameter of 100 nm or more is 40% or less of the total pore volume, preferably 5% to 40%. 6. The method according to claim 1, characterized in that: the operating conditions adopted in the first hydroprocessing described in step (2) are as follows: the reaction pressure is 10.0～17.5MPa, and the liquid hourly volume space velocity is 0.1～17.5MPa 2.0h ^-1 , the volume ratio of hydrogen to oil is 380～1000:1, the reaction temperature is 350～411℃, and the preferred operating conditions are as follows: the reaction pressure is 12.0～17.0MPa, and the liquid hourly volume space velocity is 0.1～0.6h ^-1 , the volume ratio of hydrogen to oil is 500～1000:1, and the reaction temperature is 375～390℃; The operating conditions of the second hydrotreating described in step (3) are as follows: the reaction pressure is 5-10 MPa, the liquid hourly volume space velocity is 0.5-2.0 h ^-1 , the volume ratio of hydrogen to oil is 500-1000:1, the reaction temperature It is 350～390 ℃. 7. The method according to claim 1, characterized in that: the second hydrotreating catalyst used in the second hydrotreating described in step (3) is a residue hydrodesulfurization catalyst, preferably, the second hydrotreating catalyst The treatment catalyst includes a carrier and a hydrogenation active metal component, wherein the carrier adopts an alumina-based carrier, and the hydrogenation active metal component is a metal of Group VIB and/or a metal of Group VIII, and the metal of Group VIB is selected From at least one of Mo and W, the Group VIII metal is selected from at least one of Co and Ni; preferably, based on the weight of the catalyst, the content of the hydrogenation active metal oxide is 20% to 35%, Preferably, the ratio of Group VIB metal in oxide to Group VIII metal in oxide is 1 to 6:1. 8. The method according to claim 1 or 7, wherein the properties of the second hydrotreating catalyst used in the second hydrotreating described in step (3) are as follows: the pore volume is 0.2 to 0.6 mL/g , the specific surface area is 100～250m ² /g, and the bulk density is 0.65～0.95g/mL. 9. The method according to claim 1, characterized in that: in the second hydroprocessing product described in step (3), the sulfur content is below 0.5 wt %, the residual carbon value is below 5 wt %, and metal impurities are The content of Ni and V is 40 μg/g or less. 10. The method according to any one of claims 1 to 9, wherein the inferior heavy oil described in step (1) is heavy oil containing asphaltenes, derived from petroleum hydrocarbons and/or other mineral oils, wherein petroleum hydrocarbon sources For residual oil and/or crude oil, wherein the residual oil is selected from one or more of vacuum residual oil and atmospheric pressure residual oil, and the crude oil is selected from heavy oil; other mineral oils are coal liquefied oil, oil sand oil and shale oil Preferably, in the inferior heavy oil, the content of metal impurities V and Ni is more than 150 μg/g, the weight content of carbon residue is more than 10%, and the weight content of sulfur is more than 3wt%.