A heavy oil processing technology and processing system

Abstract

The present invention discloses a heavy oil processing process and a processing system. The heavy oil processing process includes the following steps: The heavy oil raw material enters the first fluidized bed reaction zone for reaction, and the reaction products are separated to obtain a first gas-phase stream and a first liquid-phase stream; the obtained first liquid-phase stream enters the second fluidized bed reaction zone for reaction, and the reaction products are separated to obtain a second gas-phase stream and a second liquid-phase stream; the second liquid-phase stream is separated to obtain a light fraction and a heavy fraction; the obtained heavy fraction enters the first extraction zone, and after contacting with the extraction solvent, a first extraction phase stream and a first raffinate phase stream are obtained; the first extraction phase stream enters the second extraction zone, and after contacting with the extraction solvent, a second extraction phase stream and a second raffinate phase stream are obtained; the second extraction phase stream enters the separation unit, and after recovering the extraction solvent, an oil-phase stream is obtained. A heavy oil processing system adopting the above processing process is also provided. The heavy oil processing process and the processing system provided by the present invention can realize the operation of fluidized bed heavy oil hydrogenation at a high conversion rate, and at the same time ensure the long-term stable operation of the device.

Description

Technical Field

[0001] The present invention belongs to the technical field of petrochemical engineering, and particularly relates to a heavy oil ebullated bed processing technology and processing system. Background Art

[0002] In recent years, the deep processing of inferior heavy oil has become the focus of the technical development of the refining industry, mainly including hydrogenation technology and decarbonization technology. Among them, the ebullated bed heavy oil hydrogenation technology has significant advantages in heavy oil lightening. It has the advantages of online catalyst replacement, high utilization rate, long operation cycle, and flexible unit operation, etc., and can meet the requirements of unit large-scale and long-term operation, playing a crucial role in the existing refining transformation process.

[0003] At present, the world's ebullated bed hydrocracking technologies mainly include the H-Oil process and T-Star process of Axens Company in France, and the LC-Fining process of CLG Company in the United States. There are nearly 30 sets of ebullated bed hydrocracking units globally. Currently, 3 sets of H-Oil ebullated bed hydrocracking units have been introduced in China, which are built in Hengli Petrochemical and Sinopec Zhenhai Refining & Chemical respectively, with a total residue oil processing capacity of 9 million tons per year. With the heavy quality of the processed crude oil, as a crucial link in the refinery, the ebullated bed hydrocracking technology becomes more prominent in its advantages.

[0004] CN 106947523 A discloses a method for ebullated bed residue oil hydrocracking. This method includes two series-connected ebullated bed reactors. A residue oil hydrotreating catalyst is used in the first ebullated bed reactor, and a residue oil hydrocracking catalyst is used in the second ebullated bed reactor. Under this catalyst configuration, the sediment is relatively high at high conversion rates, making it difficult to ensure the stable long-term operation of the unit.

[0005] USP3809644 discloses a multi-stage ebullated bed hydrogenation process, which is used to produce low-sulfur fuel oil from petroleum residua with high sulfur and high metal contents. This process includes three reactors. The first reactor is filled with a demetallization catalyst, the second reactor is filled with a demetallization and desulfurization catalyst, and the third reactor is filled with a desulfurization catalyst. This method uses conventional residue oil hydrotreating catalysts, with a relatively low conversion rate for residua. If the conversion rate is increased, the formation of sediment in the product oil will increase, thus affecting the operation cycle of the unit.

[0006] CN103102944A discloses an integrated method for residue oil hydrocracking and solvent deasphalting. After the residue oil hydrocarbon fraction and hydrogen react in the first ebullated bed hydroconversion reactor system, they enter the fractionation system. The vacuum residue enters the solvent deasphalting system to obtain deoiled asphalt and deasphalted oil. The deoiled asphalt and deasphalted oil are respectively subjected to hydrotreating, and the product oil enters the fractionation system. In this process, a vacuum fractionation unit is configured in the fractionation system, and there is still a risk of coking.

[0007] CN108102706A discloses a heavy oil hydrotreating method. The heavy oil feedstock is fractionated to obtain a light fraction and a heavy fraction. The heavy fraction enters a solvent deasphalting unit, and after treatment, deasphalted oil and deoiled asphalt are obtained. The deasphalted oil is subjected to fixed-bed hydrotreating, and the product oil obtained from the fixed-bed hydrotreating enters a fluidized-bed hydrocracking reaction zone. The reaction effluent from the fluidized-bed hydrocracking reaction zone is separated to obtain gas, gasoline, diesel, wax oil, and unconverted oil. In this heavy oil treatment method, the coking tendency of the subsequent fractionation system of the fluidized-bed is very low, mainly due to the high quality of the processing feedstock. The conversion rate of the heavy fraction in this process flow is relatively low. At the same time, the fluidized-bed hydrotreating does not give full play to its strong adaptability to inferior feedstocks, and it is difficult to achieve efficient conversion of heavy feedstocks. Summary of the Invention

[0008] During the research process, the applicant found that the core factor restricting the long-term stable operation of the fluidized-bed heavy oil hydrotreating unit is the coking problem in the fractionation system. In particular, the coking of the vacuum fractionation tower in the fractionation system seriously affects the long-term stable operation of the entire unit. The vacuum fractionation tower needs to be decoked regularly. At the same time, the heat exchanger of the bottom oil of the vacuum tower (usually a spiral plate heat exchanger) is prone to blockage, and it needs to be cleaned regularly and a spare heat exchanger is set for switching use, which greatly increases the investment cost and operating cost of the unit. Research shows that the subsequent fractionation unit of the fluidized-bed is prone to coking because the stable colloidal structure in petroleum is destroyed during the hydroconversion process. The stability of petroleum colloid depends on the hydrocarbon composition and content of petroleum, and the stability is in a dynamic equilibrium. Only when the content and composition of the four components in the oil phase match, the system can exist stably. After hydrogenation, the stability of the residue colloid decreases and the stability coefficient decreases. Compared with the fixed-bed residue hydrotreating process, the fluidized-bed residue hydrotreating process generally operates at a higher residue conversion rate, which will inevitably cause the residue system to be more easily damaged, and the content of sediments reflecting the stability parameters in the hydrogenated product oil is relatively high. However, the fluidized-bed hydrotreating technology can convert more heavy components in the residue into light oil products and chemical raw materials, and can realize the on-line addition and discharge of catalysts to ensure the long-term operation of the unit. It is a very advantageous hydrotreating technology in the current refinery structure transformation process.

[0009] Aiming at the deficiencies in the prior art, the main object of the present invention is to provide a heavy oil processing process and a processing system, which can realize the operation of the fluidized-bed heavy oil hydrotreating at a high conversion rate while ensuring the long-term stable operation of the unit.

[0010] The first aspect of the present invention provides a heavy oil processing process, including the following steps:

[0011] (1) The heavy oil feedstock enters the first fluidized-bed reaction zone and reacts under the action of hydrogen and the first hydrogenation catalyst. The reaction product is separated to obtain a first gas-phase stream and a first liquid-phase stream;

[0012] (2) The first liquid-phase feed stream obtained in step (1) enters the second fluidized-bed reaction zone and reacts under the action of hydrogen and the second hydrogenation catalyst. After separation of the reaction products, a second gas-phase feed stream and a second liquid-phase feed stream are obtained.

[0013] (3) The second liquid-phase feed stream obtained in step (2) is separated to obtain a light fraction and a heavy fraction.

[0014] (4) The heavy fraction obtained in step (3) enters the first extraction zone and contacts with the extraction solvent to obtain a first extraction-phase feed stream and a first raffinate-phase feed stream.

[0015] (5) The first extraction-phase feed stream obtained in step (4) enters the second extraction zone and contacts with the extraction solvent to obtain a second extraction-phase feed stream and a second raffinate-phase feed stream.

[0016] (6) The second extraction-phase feed stream obtained in step (5) enters the separation unit, and after recovering the extraction solvent, an oil-phase feed stream is obtained.

[0017] Further, in the above heavy oil processing process, the heavy oil raw material in step (1) can be selected from one or more of atmospheric residue, vacuum residue, oilfield heavy oil, heavy fuel oil, oil sand, coal tar, ethylene tar, etc., and at the same time, one or more of catalytic slurry, vacuum gas oil, and furfural extract oil can be optionally blended.

[0018] Further, in the above heavy oil processing process, at least one fluidized-bed hydrotreating reactor is provided in the first fluidized-bed reaction zone. The fluidized-bed reactor can adopt at least one of the existing fluidized-bed reactors. Specifically, a fluidized-bed reactor with a recycle cup, a STRONG fluidized-bed reactor with an internal three-phase separator developed by Dalian Petrochemical Research Institute of Sinopec can be adopted. Preferably, a STRONG fluidized-bed reactor with an internal three-phase separator developed by Dalian Petrochemical Research Institute of Sinopec is adopted. When a fluidized-bed reactor with a recycle cup is used, a unit with gas-liquid separation function needs to be provided between the first fluidized-bed reaction zone and the second fluidized-bed reaction zone. For example, a high-pressure separation unit is adopted. Its main purpose is to separate hydrogen and light hydrocarbon components from the heavy fraction in the reaction products of the first fluidized-bed reactor. When a STRONG fluidized-bed reactor with an internal three-phase separator developed by Dalian Petrochemical Research Institute of Sinopec is used, since the STRONG fluidized-bed reactor has an internal three-phase separator, gas-liquid separation can be directly achieved in the reactor, and a unit with gas-liquid separation function does not need to be provided.

[0019] Further, in the above heavy oil processing technology, the operating conditions of the first fluidized bed reaction zone are as follows: the reaction temperature is 350 - 450°C, preferably 380 - 430°C; the reaction pressure is 10.0 - 20.0 MPa, preferably 15.0 - 18.0 MPa; the hydrogen-oil volume ratio is 400 - 2000, preferably 500 - 1500; and the liquid hourly space velocity is 0.1 - 5.0 h -1 , preferably 0.2 - 2.0 h -1 .

[0020] Further, in the above heavy oil processing technology, at least one fluidized bed hydrotreating reactor is provided in the second fluidized bed reaction zone. The fluidized bed reactor can adopt at least one of the existing fluidized bed reactors. Specifically, it can adopt a fluidized bed reactor with a recycle cup, or a STRONG fluidized bed reactor with an internal three-phase separator developed by Dalian Petrochemical Research Institute, Sinopec. Preferably, it adopts a STRONG fluidized bed reactor with an internal three-phase separator developed by Dalian Petrochemical Research Institute, Sinopec.

[0021] Further, in the above heavy oil processing technology, the first hydrotreating catalyst loaded in the first fluidized bed reaction zone can adopt a commercial catalyst or be prepared according to the preparation methods disclosed in the prior art. For example, it can adopt a series of fluidized bed hydrodemetallization catalysts developed by Dalian Petrochemical Research Institute, Sinopec. Generally, the first catalyst includes a carrier and an active metal component. The active metal is a metal of Group VIB and / or Group VIII. Specifically, it can be one or several of nickel, cobalt, molybdenum, or tungsten. The carrier can be one or several of alumina, silica, alumina-silica, or titanium oxide.

[0022] Further, in the above heavy oil processing technology, the second hydrotreating catalyst loaded in the second fluidized bed reaction zone can adopt a commercial catalyst or be prepared according to the preparation methods disclosed in the prior art. For example, it can adopt a series of fluidized bed hydrotreating catalysts developed by Dalian Petrochemical Research Institute, Sinopec. Generally, the first catalyst includes a carrier and an active metal component. The active metal is a metal of Group VIB and / or Group VIII. Specifically, it can be one or several of nickel, cobalt, molybdenum, or tungsten. The carrier can be one or several of alumina, silica, alumina-silica, or titanium oxide.

[0023] Further, in the above heavy oil processing technology, the operating conditions of the second fluidized bed reaction zone are as follows: the reaction temperature is 350 - 450°C, preferably 380 - 430°C; the reaction pressure is 10.0 - 20.0 MPa, preferably 15.0 - 18.0 MPa; the hydrogen-oil volume ratio is 400 - 2000, preferably 500 - 1500; and the liquid hourly space velocity is 0.1 - 5.0 h -1 , preferably 0.2 - 2.0 h-1 。

[0024] Furthermore, in the above heavy oil processing technology, the cutting point between the light fraction and the heavy fraction is 180 - 450°C, preferably 260 - 400°C.

[0025] Furthermore, in the above heavy oil processing technology, the first gas-phase stream and the second gas-phase stream enter the hydrogen recovery unit for treatment. The hydrogen recovery unit can adopt any one of the existing hydrogen recovery devices in the art, and those skilled in the art can make a choice according to the actual situation. Generally, it includes a hot high-pressure separator, a cold high-pressure separator, a hydrocarbon recovery unit, a recycle hydrogen desulfurization unit, and a membrane separation unit. After treatment, recycle hydrogen and light hydrocarbons are obtained. Among them, the recycle hydrogen can be recycled back to the first fluidized bed reaction zone and / or the second fluidized bed reaction zone for use.

[0026] Furthermore, in the above heavy oil processing technology, the light fraction obtained after separation of the second liquid-phase stream mainly includes naphtha fraction and diesel fraction. Among them, according to the difference in its hydrocarbon composition, the naphtha fraction can be used as a raw material for producing olefins in a steam cracking device or as a raw material for producing aromatics in a reforming device. The diesel fraction can enter a hydrofining unit to produce clean diesel products or be used as a raw material in a hydrocracking unit to produce raw materials for light chemical products.

[0027] Furthermore, in the above heavy oil processing technology, the extraction solvent used in the first extraction zone can be at least one of alkanes and naphtha, and the alkane is at least one of C3 - C7.

[0028] Furthermore, in the above heavy oil processing technology, the operating conditions of the first extraction zone are as follows: the temperature is 80 - 200°C, preferably 100 - 160°C; the pressure is 2.0 - 6.0 MPa, preferably 3.0 - 5.0 MPa; the solvent volume ratio is 1.0 - 10.0, preferably 3.0 - 8.0. The yield of the first raffinate stream is controlled at 20wt% - 70wt%, preferably 30wt% - 55wt%.

[0029] Furthermore, in the above heavy oil processing technology, all or part of the first raffinate stream can be returned to the first fluidized bed reaction zone for treatment. When part of it is returned to the first fluidized bed reaction zone, the remaining part of the stream can be used as a coking raw material to produce low-sulfur petroleum coke or as a hydrogen production raw material; or the first raffinate stream can also not be returned to the first fluidized bed reaction zone for treatment and be directly used as a coking material to produce low-sulfur petroleum coke or as a hydrogen production raw material.

[0030] Further, in the above heavy oil processing process, the first raffinate stream is preferably mixed with an oil-soluble catalyst and then returned to the first ebullated bed reaction zone. The addition amount of the oil-soluble catalyst is 0.05 wt% to 5 wt% of the weight of the first raffinate stream, preferably 0.5 wt% to 2 wt%. The oil-soluble catalyst can be a slurry bed residue hydrotreating catalyst.

[0031] Further, in the above heavy oil processing process, the extraction solvent used in the second extraction zone can be at least one of alkane and naphtha, wherein the alkane is at least one of C3 - C7.

[0032] Further, in the above heavy oil processing process, the operating conditions of the second extraction zone are as follows: the temperature is 80 - 200 °C, preferably 120 - 160 °C, the pressure is 2.0 - 6.0 MPa, preferably 3.0 - 5.0 MPa, and the solvent volume ratio is 1.0 - 10.0, preferably 3.0 - 8.0. The yield of the second raffinate stream is controlled at 10 wt% - 50 wt%, preferably 10 wt% - 30 wt%.

[0033] Further, in the above heavy oil processing process, the second raffinate stream can be wholly or partly returned to the first ebullated bed reaction zone and / or the second ebullated bed reaction zone. When partly returned, the remaining part can be used as the feed for units such as catalytic cracking, hydrocracking, and delayed coking, or as the blending component for asphalt and low-sulfur marine fuel.

[0034] Further, in the above heavy oil processing process, the second raffinate stream can also not be returned to the first ebullated bed reaction zone and / or the second ebullated bed reaction zone, and can be directly used as the feed for units such as catalytic cracking, hydrocracking, and delayed coking, or as the blending component for asphalt and low-sulfur marine fuel.

[0035] Further, in the above heavy oil processing process, the separation unit adopts supercritical solvent separation. After separation, the extracted solvent is returned to the first extraction zone and / or the second extraction zone for use, and the oil-phase stream is directly discharged from the device as a product. The oil-phase stream can be used as the feed for a hydrocracking unit or a catalytic cracking unit, and can also be used as the conveying oil or quenching oil during the on-line replacement of the hydrocatalyst used in the ebullated bed reaction zone.

[0036] The second aspect of the present invention provides a heavy oil processing system, including the following:

[0037] A first ebullated bed reaction zone, which is used to receive a heavy oil raw material and react under the action of hydrogen and a first hydrocatalyst, and the reaction product is obtained after the reaction;

[0038] A first separation unit, which is used to receive the reaction product of the first ebullated bed reaction zone and obtain a first gas-phase stream and a first liquid-phase stream after separation;

[0039] The second fluidized bed reaction zone, which is used to receive the first liquid-phase feed stream from the first separation unit, reacts under the action of hydrogen and a second hydrogenation catalyst to obtain reaction products;

[0040] The second separation unit, which is used to receive the reaction products of the second fluidized bed reaction zone, and after separation, obtains a second gas-phase feed stream and a second liquid-phase feed stream;

[0041] The third separation unit, which is used to receive the second liquid-phase feed stream from the second separation unit, and after separation, obtains a light fraction and a heavy fraction;

[0042] The first extraction zone, which is used to receive the heavy fraction from the third separation unit, and after contacting with an extraction solvent, obtains a first extract phase feed stream and a first raffinate phase feed stream;

[0043] The second extraction zone, which is used to receive the first extract phase feed stream from the first extraction zone, and after contacting with an extraction solvent, obtains a second extract phase feed stream and a second raffinate phase feed stream;

[0044] The fourth separation unit, which is used to receive the second extract phase feed stream from the second extraction zone, and after separation, obtains an extraction solvent and an oil-phase feed stream.

[0045] Furthermore, in the above heavy oil processing system, the first raffinate phase feed stream returns to the first fluidized bed reaction zone through a pipeline.

[0046] Furthermore, in the above heavy oil processing system, the second raffinate phase feed stream returns to the first fluidized bed reaction zone and / or the second fluidized bed reaction zone through a pipeline.

[0047] Furthermore, in the above heavy oil processing system, at least one fluidized bed hydroprocessing reactor is provided in the first fluidized bed reaction zone. The fluidized bed reactor can adopt at least one of the existing fluidized bed reactors. Specifically, it can adopt a fluidized bed reactor with a recycle cup or a STRONG fluidized bed reactor with an in-built three-phase separator developed by Dalian Petrochemical Research Institute of Sinopec. Preferably, it adopts a STRONG fluidized bed reactor with an in-built three-phase separator developed by Dalian Petrochemical Research Institute of Sinopec.

[0048] Furthermore, in the above heavy oil processing system, the first separation unit is a device with gas-liquid separation function, such as a gas-liquid separator. When a STRONG fluidized bed reactor with an in-built three-phase separator developed by Dalian Petrochemical Research Institute of Sinopec is adopted, the first separation unit can be omitted, and the three-phase separator in the reactor itself can realize the separation of gas-liquid two phases.

[0049] Furthermore, in the above heavy oil processing system, at least one ebullated bed hydroprocessing reactor is provided in the second ebullated bed reaction zone. The ebullated bed reactor can adopt at least one of the existing ebullated bed reactors. Specifically, it can adopt an ebullated bed reactor with a recycle cup or a STRONG ebullated bed reactor with an in-built three-phase separator developed by Dalian Petrochemical Research Institute, SINOPEC. Preferably, it adopts a STRONG ebullated bed reactor with an in-built three-phase separator developed by Dalian Petrochemical Research Institute, SINOPEC.

[0050] Furthermore, in the above heavy oil processing system, the second separation unit is a device with gas-liquid separation function, such as a gas-liquid separator. When a STRONG ebullated bed reactor with an in-built three-phase separator developed by Dalian Petrochemical Research Institute, SINOPEC is adopted, the first separation unit can be omitted, and the three-phase separator in the reactor itself can achieve the separation of gas-liquid two phases.

[0051] Furthermore, in the above heavy oil processing system, the third separation unit can adopt any one of devices such as an atmospheric fractionating column, a flash tank, etc.

[0052] Furthermore, in the above heavy oil processing system, the first extraction zone can adopt an existing extraction column. According to the internal structure of the extraction column, a rotary disk column or a packed column can be selected. Preferably, it is a packed column. The packing generally can be selected from one or several of grid, Raschig ring, Pall ring, etc. Preferably, it is a grid.

[0053] Furthermore, in the above heavy oil processing system, the second extraction zone can adopt an existing extraction column. According to the internal structure of the extraction column, a rotary disk column or a packed column can be selected. Preferably, it is a packed column. The packing generally can be selected from one or several of grid, Raschig ring, Pall ring, etc. Preferably, it is a grid.

[0054] Furthermore, in the above heavy oil processing system, the fourth separation unit includes an existing conventional solvent recovery column. Internals can be provided in the column. The internals can be trays or packings. Preferably, they are packings. The packing generally is selected from one or several of grid, Raschig ring, Pall ring, etc. Preferably, it is a grid.

[0055] Compared with the prior art, the heavy oil processing process and processing system provided by the present invention have the following advantages:

[0056] 1. The heavy oil processing system of the present invention cancels the vacuum fractionation unit after the ebullated bed conversion, and adopts a solvent deasphalting unit to achieve the fraction separation function, thereby avoiding the coking problem of the vacuum fractionation unit caused by the poor stability of the ebullated bed product oil. At the same time, by skillfully utilizing the characteristic of poor stability of the ebullated bed product oil, the solvent extraction method can better promote the fraction separation and greatly improve the separation efficiency.

[0057] 2. In the heavy oil processing process of the present invention, the different fractions separated from the oil solvent generated by ebullated bed hydrogenation are cleverly returned to different ebullated bed reaction units for processing based on their properties. The first raffinate phase stream obtained in the first extraction zone is primarily enriched in larger colloid and asphaltene molecules, contains a high concentration of aromatic components, and has a high sulfur content. However, its molecular size is significantly reduced compared to the residual oil molecules. Returning it to the first ebullated bed reaction zone fully utilizes the pore structure and hydrogenation performance of the catalyst in the first ebullated bed reaction zone, achieving efficient conversion of this fraction. Simultaneously, the second raffinate phase stream obtained in the second extraction zone, which contains a high concentration of aromatic and colloid components, enters the second ebullated bed reaction zone, further improving the stability of the reaction system. Furthermore, the relatively smaller aromatic components can be freed between the larger molecules, promoting their hydrogenation reaction and thereby increasing the residual oil conversion rate. Furthermore, the second extract phase stream can also enter the first ebullated bed reaction zone, reducing the viscosity of the feed residual oil and improving the impurity removal rate.

[0058] 3. The heavy oil processing process of the present invention is more flexible, with a flexible and adaptable product structure. The first and second raffinate phases from the extraction unit can be returned to the ebullated-bed hydrogenation unit for direct processing or can serve as feedstock for subsequent processing units. For example, the first raffinate phase can be used as a hydrogen production feedstock, while the second raffinate phase can be used as a low-sulfur marine fuel blending component or a feedstock for low-sulfur petroleum coke. The oil phase stream from the extraction unit can be used as a feedstock for hydrocracking or catalytic cracking (cracking). When the first raffinate phase from the extraction unit is returned to the first reaction zone of the ebullated-bed hydrogenation process, the use of a dispersed oil-soluble catalyst can further promote the conversion of heavy components. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 is a schematic diagram of the heavy oil processing process and processing system of the present invention;

[0060] Among them, 1-raw oil; 2-first ebullated bed reaction zone; 3-first separation unit; 4-first liquid phase feed stream; 5-second ebullated bed reaction zone; 6-first gas phase feed stream; 7-second separation unit; 8-second liquid phase feed stream; 9-third separation unit; 10-second gas phase feed stream; 11-hydrogen recovery unit; 12-circulating hydrogen; 13-heavy fraction; 14-first extraction zone; 15-first extraction phase feed stream; 16-second extraction zone; 17-second extraction phase feed stream; 18-fourth separation unit; 19-regenerated extraction solvent; 20-first raffinate phase feed stream; 21-second raffinate phase feed stream; 22-oil phase feed stream; 23-light hydrocarbon components; 24-light fraction.

[0061] Figure 2 This is a process flow chart of Comparative Example 1 of the present invention;

[0062] 1 - Feedstock oil; 2 - First ebullated bed reaction zone; 3 - First separation unit; 4 - First liquid-phase stream; 5 - Second ebullated bed reaction zone; 6 - First gas-phase stream; 7 - Second separation unit; 8 - Second gas-phase stream; 9 - Hydrogen recovery unit; 10 - Recycle hydrogen; 11 - Light hydrocarbon components; 12 - Second liquid-phase stream; 13 - Atmospheric distillation unit; 14 - Hydrotreated naphtha fraction; 15 - Hydrotreated diesel fraction; 16 - Hydrotreated atmospheric residue fraction; 17 - Vacuum distillation unit; 18 - Hydrotreated wax oil fraction; 19 - Hydrotreated vacuum residue.

[0063] Figure 3 Process flow diagram adopted in Comparative Example 2 of the present invention;

[0064] 1 - Feedstock oil; 2 - First ebullated bed reaction zone; 3 - First separation unit; 4 - First liquid-phase stream; 5 - Second ebullated bed reaction zone; 6 - First gas-phase stream; 7 - Second separation unit; 8 - Second gas-phase stream; 9 - Hydrogen recovery unit; 10 - Recycle hydrogen; 11 - Light hydrocarbon components; 12 - Second liquid-phase stream; 13 - Atmospheric distillation unit; 14 - Hydrotreated naphtha fraction; 15 - Hydrotreated diesel fraction; 16 - Hydrotreated atmospheric residue fraction; 17 - Vacuum distillation unit; 18 - Hydrotreated wax oil fraction; 19 - Hydrotreated vacuum residue; 20 - Extraction zone; 21 - Raffinate stream; 22 - Extract stream; 23 - Solvent recovery unit; 24 - Oil-phase stream; 25 - Regenerated solvent. Detailed implementation manners

[0065] The technical features of the present invention will be further described below through specific examples in combination with the accompanying drawings, but these examples shall not limit the present invention.

[0066] Such as Figure 1As shown in the figure, the heavy oil processing technology provided by the present invention includes the following: The feedstock oil 1 is mixed with hydrogen 12 and enters the first fluidized bed reaction zone 2. After the reaction, the product stream enters the first separation zone 3 and is separated into a first gas-phase stream 6 and a first liquid-phase stream 4. Among them, the first liquid-phase stream 4 is mixed with hydrogen 12 and then enters the second fluidized bed reaction zone 5. The reaction products enter the second separation zone 7 and are separated to obtain a second gas-phase stream 10 and a second liquid-phase stream 8. Among them, the second gas-phase stream 10 and the first gas-phase stream 6 enter the hydrogen recovery unit 11, and after treatment, recycled hydrogen 12 and light hydrocarbon components 23 are obtained; the second liquid-phase stream 8 enters the third separation unit 9 and is separated to obtain light fractions 24 and heavy fractions 13; the heavy fractions 13 enter the first extraction zone 14, and after contacting with the extraction solvent, a first extraction phase stream 15 and a first raffinate phase stream 20 are obtained. Among them, the first extraction phase stream 15 enters the second extraction zone 16, and after contacting with the extraction solvent, a second extraction phase stream 17 and a second raffinate phase stream 21 are obtained. The second extraction phase stream 17 enters the fourth separation unit 18, and after separation, a regenerated extraction solvent 19 and an oil-phase stream 22 are obtained. The regenerated extraction solvent 19 is returned to the first extraction zone 14 and the second extraction zone 16 for recycling.

[0067] In the examples and comparative examples of the present invention, vacuum residue obtained from the current atmospheric and vacuum distillation unit was used, with a density (20 °C) of 1.105 g / cm 3 , a sulfur content of 4.3 wt%, a nitrogen content of 5200 mg / kg, a carbon residue of 26.4 wt%, metals (nickel and vanadium) of 293.5 mg / kg, and an asphaltene content of 8.6%. It is a high-nitrogen and high-metal difficult-to-process residue, and it is relatively difficult to process this residue by the conventional fluidized bed process route. Table 1 lists the operating conditions under different examples and comparative examples.

[0068] Example 1

[0069] Example 1 adopts the Figure 1 shown process flow. Among them, the entire first raffinate phase stream 20 is returned to the first fluidized bed reaction zone 2, and the entire second raffinate phase stream 21 is returned to the second fluidized bed reaction zone 5. The FEM-10 catalyst developed by Dalian Petrochemical Research Institute is used in the first fluidized bed reaction zone; the FEM-31 catalyst developed by Dalian Petrochemical Research Institute is used in the second fluidized bed reaction zone; the third separation unit adopts an atmospheric distillation unit, where the temperature cut-off points for light and heavy fractions are controlled at 300 °C; butane solvent is selected as the solvent in the first extraction zone and the second extraction zone; the temperatures of the first fluidized bed reaction zone and the second reaction zone are 425 °C and 430 °C respectively, the reaction pressure is 17 MPa, the hydrogen-oil volume ratio is 500, and the liquid volume hourly space velocity is 0.25 h -1 . The temperatures of the first and second extraction zones are 110 °C and 125 °C respectively, the extraction pressure is 4.2 MPa, and the solvent-oil volume ratio is 5.0.

[0070] Example 2

[0071] Example 1 uses Figure 1 the process flow shown, which is basically the same as that of Example 1. The difference is that a part of the first raffinate stream 20 is returned to the first fluidized bed reaction zone 2, which is 10 wt% relative to the fresh feed. The second raffinate stream 21 is not returned to the second fluidized bed reaction zone 5. The first fluidized bed reaction zone uses the FEM-10 catalyst developed by Dalian Petrochemical Research Institute; the second fluidized bed reaction zone uses the FEM-31 catalyst developed by Dalian Petrochemical Research Institute; the third separation unit uses an atmospheric distillation unit, where the temperature cut points of the light and heavy fractions are controlled at 300 °C; the solvents selected for the first extraction zone and the second extraction zone are butane solvents; the temperatures of the first fluidized bed reaction zone and the second reaction zone are 425 °C and 430 °C respectively, the reaction pressure is 17 MPa, the hydrogen-oil volume ratio is 500, and the liquid volume hourly space velocity is 0.25 h -1 . The temperatures of the first and second extraction zones are 110 °C and 125 °C respectively, the extraction pressure is 4.2 MPa, and the solvent-oil volume ratio is 5.0.

[0072] Example 3

[0073] Example 2 uses Figure 1 the process flow shown, which is basically the same as that of Example 1. The difference is that the first raffinate stream 20 is not returned to the first fluidized bed reaction zone 2, and a part of the second raffinate stream 21 is returned to the second fluidized bed reaction zone 5, which is 10 wt% relative to the fresh feed. The first fluidized bed reaction zone uses the FEM-10 catalyst developed by Dalian Petrochemical Research Institute; the second fluidized bed reaction zone uses the FEM-31 catalyst developed by Dalian Petrochemical Research Institute; the third separation unit uses an atmospheric distillation unit, where the temperature cut points of the light and heavy fractions are controlled at 300 °C; the solvents selected for the first extraction zone and the second extraction zone are butane solvents; the temperatures of the first fluidized bed reaction zone and the second reaction zone are 415 °C and 420 °C respectively, the reaction pressure is 15 MPa, the hydrogen-oil volume ratio is 500, and the liquid volume hourly space velocity is 0.18 h -1 . The temperatures of the first and second extraction zones are 113 °C and 130 °C respectively, the extraction pressure is 4.2 MPa, and the solvent-oil volume ratio is 5.0.

[0074] Example 4

[0075] Example 3 uses Figure 1The process flow shown is basically the same as that of Example 1, except that neither the first raffinate stream 20 nor the second raffinate stream 21 is returned to the fluidized bed reaction zone, but instead serves as feedstock for other subsequent units. The first fluidized bed reaction zone uses the FEM-10 catalyst developed by Dalian Petrochemical Research Institute; the second fluidized bed reaction zone uses the FEM-31 catalyst developed by Dalian Petrochemical Research Institute; the third separation unit uses an atmospheric distillation unit, where the temperature cut-off points for the light and heavy fractions are controlled at 300 °C; the solvent selected for the first extraction zone and the second extraction zone is butane solvent; the temperatures of the first fluidized bed reaction zone and the second reaction zone are 420 °C and 425 °C respectively, the reaction pressure is 17 MPa, the hydrogen-oil volume ratio is 500, and the liquid volume hourly space velocity is 0.2 h -1 . The temperatures of the first and second extraction zones are 110 °C and 125 °C respectively, the extraction pressure is 4.2 MPa, and the solvent-oil volume ratio is 5.0.

[0076] Example 5

[0077] Example 2 uses Figure 1 The process flow shown is basically the same as that of Example 1, except that the first raffinate stream 20 is not returned to the first fluidized bed reaction zone 2, but instead serves as feedstock for other subsequent units. Part of the second raffinate stream 21 is returned to the first fluidized bed reaction zone 2, which is 10 wt% relative to the fresh feed. The temperatures of the first fluidized bed reaction zone and the second fluidized bed reaction zone are 415 °C and 420 °C respectively, the reaction pressure is 15 MPa, the hydrogen-oil volume ratio is 500, and the liquid volume hourly space velocity is 0.18 h -1 . The temperatures of the first and second extraction zones are 113 °C and 130 °C respectively, the extraction pressure is 4.2 MPa, and the solvent-oil volume ratio is 5.0.

[0078] Comparative Example 1

[0079] Comparative Example 1 uses Figure 2 The process flow shown, as Figure 2As shown in the figure, the feedstock oil 1 is mixed with hydrogen 10 and enters the first ebullated bed reaction zone 2. After the reaction, the product stream enters the first separation zone 3 and is separated into a first gas-phase stream 6 and a first liquid-phase stream 4. The first liquid-phase stream 4 is mixed with hydrogen 10 and then enters the second ebullated bed reaction zone. The reaction products enter the second separation zone 7 and are separated to obtain a second gas-phase stream 8 and a second liquid-phase stream 12. The second gas-phase stream 8 and the first gas-phase stream 6 enter the hydrogen recovery unit 9, and after treatment, recycled hydrogen 10 and light hydrocarbon components 11 are obtained. The second liquid-phase stream 12 and the light hydrocarbon components 11 are mixed and enter the atmospheric distillation unit 13, where they are separated to obtain a hydrotreated naphtha fraction 14, a hydrotreated diesel fraction 15, and a hydrotreated atmospheric residue fraction 16. The hydrotreated atmospheric residue fraction 16 enters the vacuum distillation unit 17 and is separated to obtain a hydrotreated wax oil fraction 18 and a hydrotreated vacuum residue fraction 19. The first ebullated bed reaction zone uses the FEM-10 catalyst developed by Dalian Petrochemical Research Institute; the second ebullated bed reaction zone uses the FEM-31 catalyst developed by Dalian Petrochemical Research Institute. The temperatures of the first ebullated bed reaction zone and the second reaction zone are 415 °C and 420 °C respectively, the reaction pressure is 15 MPa, the hydrogen-oil volume ratio is 500, and the liquid hourly space velocity is 0.18 h -1 .

[0080] Comparative Example 2

[0081] Comparative Example 2 uses the Figure 3 process flow shown in the figure. As Figure 3 shown in the figure, the feedstock oil 1 is mixed with hydrogen 10 and enters the first ebullated bed reaction zone to obtain a first gas-phase stream 6 and a first liquid-phase stream 4 after the reaction product stream enters the first separation zone 3 and is separated. The first liquid-phase stream 4 is mixed with hydrogen 10 and then enters the second ebullated bed reaction zone 5. The reaction products enter the second separation zone 7 to obtain a second gas-phase stream 8 and a second liquid-phase stream 12. The second gas-phase stream 8 and the first gas-phase stream 6 enter the hydrogen recovery unit 9 to obtain hydrogen 10 and light hydrocarbon components 11. The second liquid-phase stream 12 and the light hydrocarbon components 11 are mixed and enter the atmospheric distillation unit 13 to obtain a hydrotreated naphtha fraction 14, a hydrotreated diesel fraction 15, and a hydrotreated atmospheric residue fraction 16. The hydrotreated atmospheric residue fraction 16 enters the vacuum distillation unit 17 to obtain a hydrotreated wax oil fraction 18 and a hydrotreated vacuum residue fraction 19. The hydrotreated vacuum residue fraction 19 and the extraction solvent enter the extraction zone 20 to obtain a raffinate stream 21 and an extract stream 22. The extract stream 22 enters the solvent recovery unit 23 and is separated to obtain an oil-phase stream 24 and a regenerated solvent 25. The first ebullated bed reaction zone uses the FEM-10 catalyst developed by Dalian Petrochemical Research Institute; the second ebullated bed reaction zone uses the FEM-31 catalyst developed by Dalian Petrochemical Research Institute; the temperatures of the first ebullated bed reaction zone and the second reaction zone are 415 °C and 420 °C respectively, the reaction pressure is 15 MPa, the hydrogen-oil volume ratio is 500, and the liquid hourly space velocity is 0.18 h -1。The temperature in the extraction zone is 110 °C, the extraction pressure is 4.2 MPa, and the solvent-to-oil volume ratio is 5.0.

[0082] Table 1 Reaction results of the examples

[0083]

[0084] Note: The yield of light oil products is mainly the liquid phase yield after removing the first raffinate stream, hydrocracked vacuum residue or raffinate stream.

[0085] Table 2 Reaction results of the comparative examples

[0086]

Claims

1. A heavy oil processing process, comprising the following steps: (1) The heavy oil raw material enters the first fluidized bed reaction zone and reacts under the action of hydrogen and the first hydrogenation catalyst. After separation of the reaction products, a first gas-phase stream and a first liquid-phase stream are obtained; (2) The first liquid-phase stream obtained in step (1) enters the second fluidized bed reaction zone and reacts under the action of hydrogen and the second hydrogenation catalyst. After separation of the reaction products, a second gas-phase stream and a second liquid-phase stream are obtained; (3) The second liquid-phase stream obtained in step (2) is separated to obtain a light fraction and a heavy fraction; (4) The heavy fraction obtained in step (3) enters the first extraction zone and contacts with the extraction solvent to obtain a first extract phase stream and a first raffinate phase stream; all or part of the first raffinate phase stream is returned to the first fluidized bed reaction zone for treatment; (5) The first extract phase stream obtained in step (4) enters the second extraction zone and contacts with the extraction solvent to obtain a second extract phase stream and a second raffinate phase stream; all or part of the second raffinate phase stream is returned to the second fluidized bed reaction zone; (6) The second extract phase stream obtained in step (5) enters the separation unit, and after recovering the extraction solvent, an oil-phase stream is obtained.

2. The heavy oil processing process according to claim 1, characterized in that: The heavy oil raw material in step (1) is selected from one or more of atmospheric residue, vacuum residue, oilfield heavy oil, oil sand, coal tar, and ethylene tar.

3. The heavy oil processing process according to claim 1 or 2, characterized in that: In step (1), one or more of catalytic oil slurry, vacuum gas oil, and furfural extract oil are blended.

4. The heavy oil processing process according to claim 1, characterized in that: The operating conditions of the first fluidized bed reaction zone are as follows: the reaction temperature is 350 - 450 °C, the reaction pressure is 10.0 - 20.0 MPa, the hydrogen-oil volume ratio is 400 - 2000, and the liquid hourly space velocity is 0.1 - 5.0 h -1 .

5. The heavy oil processing process according to claim 1, characterized in that: The operating conditions of the first fluidized bed reaction zone are as follows: the reaction temperature is 380 - 430 °C, the reaction pressure is 15.0 - 18.0 MPa, the hydrogen-oil volume ratio is 500 - 1500, and the liquid hourly space velocity is 0.2 - 2.0 h -1 .

6. The heavy oil processing process according to claim 1, characterized in that: The operating conditions of the second fluidized bed reaction zone are as follows: the reaction temperature is 350 - 450 °C, the reaction pressure is 10.0 - 20.0 MPa, the hydrogen-oil volume ratio is 400 - 2000, and the liquid hourly space velocity is 0.1 - 5.0 h -1 .

7. The heavy oil processing process according to claim 1, characterized in that: The operating conditions of the second fluidized bed reaction zone are as follows: the reaction temperature is 380 - 430 °C, the reaction pressure is 15.0 - 18.0 MPa, the hydrogen-oil volume ratio is 500 - 1500, and the liquid hourly space velocity is 0.2 - 2.0 h -1 .

8. The heavy oil processing process according to claim 1, characterized in that: The cut point between the light fraction and the heavy fraction is 180 - 450 °C.

9. The heavy oil processing process according to claim 1, characterized in that: The cut point between the light fraction and the heavy fraction is 260 - 400 °C.

10. The heavy oil processing process according to claim 1, characterized in that: The extraction solvent used in the first extraction zone is at least one of alkane and naphtha, wherein the alkane is at least one of C3 - C7 alkanes.

11. The heavy oil processing process according to claim 1, characterized in that: The operating conditions of the first extraction zone are: temperature is 80 - 200 °C, pressure is 2.0 - 6.0 MPa, and solvent volume ratio is 1.0 - 10.

0.

12. The heavy oil processing process according to claim 1, characterized in that: The operating conditions of the first extraction zone are: temperature is 100 - 160 °C, pressure is 3.0 - 5.0 MPa, and solvent volume ratio is 3.0 - 8.

0.

13. The heavy oil processing process according to claim 1, characterized in that: The yield of the first raffinate phase stream is 20wt% - 70wt%.

14. The heavy oil processing process according to claim 1, characterized in that: The yield of the first raffinate phase stream is 30wt% - 55wt%.

15. The heavy oil processing process according to claim 1, characterized in that: The first raffinate phase stream is mixed with an oil-soluble catalyst and then returned to the first fluidized bed reaction zone. The addition amount of the oil-soluble catalyst is 0.05wt% - 5wt% of the weight of the first raffinate phase stream.

16. The heavy oil processing process according to claim 1, characterized in that: The first raffinate phase stream is mixed with an oil-soluble catalyst and then returned to the first fluidized bed reaction zone. The addition amount of the oil-soluble catalyst is 0.5wt% - 2wt% of the weight of the first raffinate phase stream.

17. The heavy oil processing process according to claim 1, characterized in that: The extraction solvent used in the second extraction zone is at least one of alkane and naphtha, wherein the alkane is at least one of C3 - C7 alkanes.

18. The heavy oil processing process according to claim 1, characterized in that: The operating conditions of the second extraction zone are: temperature is 80 - 200 °C, pressure is 2.0 - 6.0 MPa, and solvent volume ratio is 1.0 - 19. The heavy oil processing process according to claim 1, wherein: ​ 20. The heavy oil processing process according to claim 1, characterized in that: ​ 21. The heavy oil processing process according to claim 1, characterized in that: The recovery rate of the second raffinate phase material flow is 10 wt% to 30 wt%.

22. The heavy oil processing process according to claim 1, characterized in that: The separation unit in step (6) uses supercritical solvent separation, and the extracted solvent obtained after separation is returned to the first extraction zone and / or the second extraction zone for use.

23. A heavy oil processing system for implementing the heavy oil processing process described in any one of claims 1-22, including the following: A first fluidized bed reaction zone, which is used to receive a heavy oil raw material and react under the action of hydrogen and a first hydrogenation catalyst to obtain a reaction product after the reaction; A first separation unit, which is used to receive the reaction product of the first fluidized bed reaction zone and obtain a first gas-phase material flow and a first liquid-phase material flow after separation; A second fluidized bed reaction zone, which is used to receive the first liquid-phase material flow from the first separation unit and react under the action of hydrogen and a second hydrogenation catalyst to obtain a reaction product; A second separation unit, which is used to receive the reaction product of the second fluidized bed reaction zone and obtain a second gas-phase material flow and a second liquid-phase material flow after separation; A third separation unit, which is used to receive the second liquid-phase material flow from the second separation unit and obtain a light fraction and a heavy fraction after separation; A first extraction zone, which is used to receive the heavy fraction from the third separation unit, contact with an extraction solvent to obtain a first extraction phase material flow and a first raffinate phase material flow; the first raffinate phase material flow returns to the first fluidized bed reaction zone through a pipeline; A second extraction zone, which is used to receive the first extraction phase material flow from the first extraction zone, contact with an extraction solvent to obtain a second extraction phase material flow and a second raffinate phase material flow; the second raffinate phase material flow returns to the second fluidized bed reaction zone through a pipeline; A fourth separation unit, which is used to receive the second extraction phase material flow from the second extraction zone and obtain an extraction solvent and an oil-phase material flow after separation.

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