METHOD AND DEVICE FOR VISCOSITY-REDUCING AND UPGRADING OF LOW-GRADE HEAVY OIL

Abstract

Provided is a method and device for viscosity-reducing and upgrading of low-grade heavy oil. The method comprises: (a) performing visbreaking reaction on low-grade heavy oil raw material and controlling the content of toluene insolubles in the produced oil; (b) mixing the produced oil in step (a) with hydrogen in a gas-liquid mixer to obtain a hydrogen-oil mixture in liquid state, or mixing the produced oil in step (a) with hydrogen to obtain hydrogen-oil mixture in gas-liquid state; in the presence of a hydrogenation catalyst, performing hydrogenation reaction on the hydrogen-oil mixture in liquid state or the hydrogen-oil mixture in gas-liquid state in the reactor, and obtaining a viscosity-reduced and upgraded oil after the reaction. It is viscosity-reducing and upgrading method by combining thermal visbreaking and fixed-bed hydrogenation, which can solve the problems of high viscosity, high density and poor stability of low-grade heavy oil products in the prior art.

Claims

1. A method for viscosity-reducing and upgrading of low-grade heavy oil, comprising: (a) performing a visbreaking reaction on the low-grade heavy oil raw material and controlling the content of toluene insolubles in the produced oil; (b) mixing the produced oil obtained in step (a) with hydrogen in a gas-liquid mixer to obtain a hydrogen-oil mixture in liquid state, or mixing the produced oil obtained in step (a) with hydrogen to obtain a hydrogen-oil mixture in gas-liquid state; in the presence of a hydrogenation catalyst, performing a hydrogenation reaction on the hydrogen-oil mixture in liquid state or the hydrogen-oil mixture in gas-liquid state in the reactor, and obtaining a viscosity-reduced and upgraded oil after the reaction.

2. The method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 1, wherein in step (a), the low-grade heavy oil raw material includes at least one selected from the group consisting of heavy crude oil, oil sand bitumen, atmospheric residuum and vacuum residuum.

3. The method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 1, wherein in step (a), the mass content of toluene insolubles in the produced oil is controlled to be less than 1.0%.

4. The method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 1, wherein in step (a), the visbreaking reaction is thermal visbreaking reaction, and the operating process conditions are: a reaction temperature ranging from 360 to 500° C., a reaction pressure ranging from 0.1 to 6.0 MPa, a residence time ranging from 1 to 120 minutes, and a mass conversion rate of the visbreaking reaction ranging from 1 to 80%.

5. The method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 1, wherein the method fluffier comprises: fractionating the produced oil obtained in step (a) to obtain a light distillate oil and a heavy distillate oil; and then mixing the light distillate oil and hydrogen in a gas-liquid mixer to obtain a hydrogen-oil mixture in liquid state, or mixing the light distillate oil and hydrogen to obtain a hydrogen-oil mixture in gas-liquid state; in the presence of a hydrogenation catalyst, performing a hydrogenation reaction on the hydrogen-oil mixture in liquid state or the hydrogen-oil mixture in gas-liquid state in the reactor, and obtaining a viscosity-reduced and upgraded oil after the reaction.

6. The method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 5, wherein the cut point of the light distillate oil and the heavy distillate oil is 400 to 565° C.

7. The method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 5, wherein the method further comprises: mixing the hydrogenated liquid product obtained by the hydrogenation reaction with the heavy distillate oil to obtain a viscosity-reduced and upgraded oil.

8. The method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 1, wherein in step (b), the hydrogenation reaction is carried out in a fixed-bed reactor, and the hydrogen-oil mixture enters the fixed-bed reactor from the top or bottom of the fixed-bed reactor.

9. The method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 1, wherein in step (b), the hydrogenation reaction process conditions are: a reaction pressure ranging from 1.0 to 20.0 MPa, a reaction temperature ranging from 260 to 450° C., and a liquid hourly volumetric space velocity ranging from 0.1 to 10.0 h.sup.−1; and in the hydrogen-oil mixture in gas-liquid state, the volume ratio of hydrogen to oil is in the range of 20 to 2000.

10. The method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 8, wherein in step (b), the hydrogenation reaction process conditions are: a reaction pressure ranging from 1.0 to 20.0 MPa, a reaction temperature ranging from 260 to 450° C., and a liquid hourly volumetric space velocity ranging from 0.1 to 10.0 h.sup.−1; and in the hydrogen-oil mixture in gas-liquid state, the volume ratio of hydrogen to oil is in the range of 20 to 2000.

11. The method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 8, wherein there are one or more fixed-bed reactors; when there are two fixed-bed reactors, the setting mode and operation steps of the two fixed-bed reactors are either of the following two instances: the first instance: the two fixed-bed reactors being arranged in parallel, and the inlet pipelines of the two fixed-bed reactors being respectively provided with feed valves; (S1) closing the feed valve of the second fixed-bed reactor, opening the feed valve of the first fixed-bed reactor, and using the first fixed-bed reactor for hydrogenation reaction; (S2) when the hydrogenation catalyst in the first fixed-bed reactor is deactivated, opening the feed valve of the second fixed-bed reactor, using the second fixed-bed reactor for hydrogenation reaction, closing the feed valve of the first fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the first fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst; (S3) when the hydrogenation catalyst in the second fixed-bed reactor is deactivated, opening the feed valve of the first fixed-bed reactor, using the first fixed-bed reactor for hydrogenation reaction, closing the feed valve of the second fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the second fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst; (S4) repeating steps (S1) to (S3) for hydrogenation reaction; the second instance: the inlet and outlet pipelines of the two fixed-bed reactors being provided with a feed valve and a discharge valve respectively; a pipeline with a one-way valve being connected before the discharge valve of each fixed-bed reactor, and being connected behind the feed valve of the other fixed-bed reactor, so that materials can be introduced from the outlet of one fixed-bed reactor to the inlet of the other reactor; S1) in the initial stage of the reaction, using the two fixed-bed reactors together, the hydrogen-oil mixture first entering the first fixed-bed reactor, and then entering the second fixed-bed reactor through the pipeline with a one-way valve for hydrogenation reaction; S2) after a period of reaction, when the activity of the hydrogenation catalyst in the first fixed-bed reactor is close to the mid-to-late stage, changing the flow direction of the hydrogen-oil mixture so that the hydrogen-oil mixture first enters the second fixed-bed reactor, and then enters the first fixed-bed reactor through the pipeline with a one-way valve; S3) when the hydrogenation catalyst in the first fixed-bed reactor is in the deactivation stage, closing the feed valve of the first fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the first fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst, and at this time, the hydrogen-oil mixture only entering the second fixed-bed reactor; S4) after the catalyst in the first fixed-bed reactor is replaced, the hydrogen-oil mixture first entering the second fixed-bed reactor, and then entering the first fixed-bed reactor where the catalyst has been replaced, through the pipeline with a one-way valve; S5) when the hydrogenation catalyst in the second fixed-bed reactor is in the deactivation stage, closing the feed valve of the second fixed-bed reactor, and replacing the hydrogenation catalyst in the second fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst, and at this time, the hydrogen-oil mixture only entering the first fixed-bed reactor; and S6) after the catalyst in the second fixed-bed reactor is replaced, repeating steps (S1) to (S5) for hydrogenation reaction.

12. The method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 1, wherein in step (b), the hydrogenation catalyst contains at least one of Mo, Ni, Co, and W, the pore volume of the hydrogenation catalyst is in the range of 0.6-1.8 mL/g, the specific surface area is in the range of 40 to 280 m.sup.2/g, and the volume of pores with a pore diameter greater than 50 nm in the hydrogenation catalyst accounts for more than 20% of total pore volume.

13. The method for viscosity-reducing upgrading of low-grade heavy oil according to claim 12, wherein the pore structure of the hydrogenation catalyst presents a bimodal distribution or a trimodal distribution; and when the pore structure of the hydrogenation catalyst presents a bimodal distribution, the most probable pore diameter of the small pores is 10 to 50 nm, and the most probable pore diameter of the large pores is 50 to 5000 nm; when the pore structure of the hydrogenation catalyst presents a trimodal distribution, the most probable pore diameters are 10 to 50 nm, 50 to 500 nm, and 500 to 5000 nm, respectively.

14. The method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 12, wherein the hydrogenation catalyst is a sulfided catalyst.

15. The method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 1, wherein in step (b), the viscosity-reduced and upgraded oil has a kinematic viscosity at 20° C. of less than 1200 cSt and an API degree of greater than 14.

16. A device for viscosity-reducing and upgrading of low-grade heavy oil, for carrying out the method for viscosity-reducing and upgrading of low-grade heavy oil according to claim 1, wherein: when the raw material for the hydrogenation reaction in the method for viscosity-reducing and upgrading of low-grade heavy oil is a hydrogen-oil mixture in gas-liquid state, the device for viscosity-reducing and upgrading of low-grade heavy oil includes: a visbreaking device and a fixed-bed reactor, wherein the liquid outlet is connected to the inlet of the fixed-bed reactor through a pipeline; when the raw material for the hydrogenation reaction in the method for viscosity-reducing and upgrading of low-grade heavy oil is a hydrogen-oil mixture in liquid state, the device for viscosity-reducing and upgrading of low-grade heavy oil includes: a visbreaking device, a gas-liquid mixer and a fixed-bed reactor, wherein the gas-liquid mixer is provided with at least a gas inlet, a liquid inlet and a liquid outlet; the liquid outlet of the visbreaking device is connected to the liquid inlet of the gas-liquid mixer through a pipeline, and the liquid outlet of the gas-liquid mixer is connected to the inlet of the fixed-bed reactor through a pipeline.

17. The device for viscosity-reducing and upgrading of low-grade heavy oil according to claim 16, wherein the device further comprises a fractionation column; when the raw material for the hydrogenation reaction in the method for viscosity-reducing and upgrading of low-grade heavy oil is a hydrogen-oil mixture in gas-liquid state, the liquid outlet of the visbreaking device is connected to the liquid inlet of the fractionation column through a pipeline, and the light distillate oil outlet of the fractionation column is connected to the inlet of the fixed-bed reactor through a pipeline; when the raw material for the hydrogenation reaction in the method for viscosity-reducing and upgrading of low-grade heavy oil is a hydrogen-oil mixture in liquid state, the liquid outlet of the visbreaking device is connected to the liquid inlet of the fractionation column through a pipeline, the light distillate oil outlet of the fractionation column is connected to the liquid inlet of the gas-liquid mixer through a pipeline, and the liquid outlet of the gas-liquid mixer is connected to the inlet of the fixed-bed reactor through a pipeline.

18. The device for viscosity-reducing and upgrading of low-grade heavy oil according to claim 17, wherein the device further comprises a storage tank for the viscosity-reduced and upgraded oil, and the heavy distillate oil outlet of the fractionation column and the outlet of the fixed-bed reactor are respectively connected to the storage tank for the viscosity-reduced and upgraded oil through pipelines.

19. The device for viscosity-reducing and upgrading of low-grade heavy oil according to claim 16, wherein there are one or more fixed-bed reactors; and when there are two fixed-bed reactors, the two fixed-bed reactors are arranged in parallel, each of the inlet pipelines of the two fixed-bed reactors is provided with a feed valve.

20. The device for viscosity-reducing and upgrading of low-grade heavy oil according to claim 16, wherein there are one or more fixed-bed reactor; and when there are two fixed-bed reactors, the inlet and outlet pipelines of the two fixed-bed reactors are respectively provided with a feed valve and a discharge valve; a pipeline with a one-way valve is connected before the discharge valve of each fixed-bed reactor, and is connected behind the feed valve of the other fixed-bed reactor, so that materials can be introduced from the outlet of one fixed-bed reactor to the inlet of the other reactor.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0071] In order to explain the embodiments of the present disclosure or the technical solutions in the prior art more clearly, the drawings needed in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are some examples of the present disclosure. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.

[0072] FIG. 1 is a structural schematic diagram of a device for viscosity-reducing and upgrading of low-grade heavy oil as provided in Example 1 of the present disclosure.

[0073] FIG. 2 is a structural schematic diagram of a device for viscosity-reducing and upgrading of low-grade heavy oil as provided in Example 2 of the present disclosure.

[0074] FIG. 3 is a structural schematic diagram of a device for viscosity-reducing and upgrading of low-grade heavy oil as provided in Example 3 of the present disclosure.

[0075] FIG. 4 is a structural schematic diagram of a device for viscosity-reducing and upgrading of low-grade heavy oil as provided in Example 4 of the present disclosure.

[0076] FIG. 5 is a structural schematic diagram of a device for viscosity-reducing and upgrading of low-grade heavy oil as provided in Example 5 of the present disclosure.

[0077] FIG. 6 is a structural schematic diagram of a device for viscosity-reducing and upgrading of low-grade heavy oil as provided in Example 6 of the present disclosure.

[0078] FIG. 7 is a structural schematic diagram of a device for viscosity-reducing and upgrading of low-grade heavy oil as provided in Example 7 of the present disclosure.

[0079] FIG. 8 is a structural schematic diagram of a device for viscosity-reducing and upgrading of low-grade heavy oil as provided in Example 8 of the present disclosure.

[0080] FIG. 9 is a structural schematic diagram of a device for viscosity-reducing and upgrading of low-grade heavy oil as provided in Example 9 of the present disclosure.

[0081] FIG. 10 is a structural schematic diagram of a device for viscosity-reducing and upgrading of low-grade heavy oil as provided in Example 10 of the present disclosure.

[0082] FIG. 11 is a structural schematic diagram of a device for viscosity-reducing and upgrading of low-grade heavy oil as provided in Example 11 of the present disclosure.

[0083] FIG. 12 is a structural schematic diagram of a device for viscosity-reducing and upgrading of low-grade heavy oil as provided in Example 12 of the present disclosure.

DESCRIPTION OF MAIN REFERENCE SIGNS

[0084] 1. visbreaking device; [0085] 2. gas-liquid mixer; [0086] 3. fixed-bed reactor; [0087] 31. first fixed-bed reactor; [0088] 32. second fixed-bed reactor; [0089] 4. fractionation column; [0090] 5. storage tank for the viscosity-reduced and upgraded oil.

DESCRIPTION OF EMBODIMENTS

[0091] In order to have a clearer understanding of the technical features, objectives and beneficial effects of the present disclosure, the technical solutions of the present disclosure are described in detail below in conjunction with the following specific examples, but they cannot be understood as limiting the scopes of the present disclosure.

Example 1

[0092] This example provides a device for viscosity-reducing and upgrading of low-grade heavy oil, of which the structural schematic diagram is shown in FIG. 1. As can be seen from FIG. 1, the device includes: a visbreaking device 1; a gas-liquid mixer 2; and a fixed-bed reactor 3. The gas-liquid mixer 2 is provided with at least a gas inlet, a liquid inlet and a liquid outlet. The liquid outlet of the visbreaking device 1 is connected to the liquid inlet of the gas-liquid mixer 2 through a pipeline, and the liquid outlet of the gas-liquid mixer 2 is connected to the inlet of the fixed-bed reactor 3 through a pipeline.

Example 2

[0093] This example provides a device for viscosity-reducing and upgrading of low-grade heavy oil, of which the structural schematic diagram is shown in FIG. 2. As can be seen from FIG. 2, the device includes: a visbreaking device 1; a gas-liquid mixer 2; and two fixed-bed reactors, a first fixed-bed reactor 31 and a second fixed-bed reactor 32, which are arranged in parallel. The gas-liquid mixer 2 is provided with at least a gas inlet, a liquid inlet, and a liquid outlet. The liquid outlet of the visbreaking device 1 is connected to the liquid inlet of the gas-liquid mixer 2 through a pipeline, and the liquid outlet of the gas-liquid mixer 2 is connected to the inlets of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 through a first feed valve and a second feed valve respectively through pipelines.

Example 3

[0094] This example provides a device for viscosity-reducing and upgrading of low-grade heavy oil, of which the structural schematic diagram is shown in FIG. 3. As can be seen from FIG. 3, the device includes: a visbreaking device 1; a gas-liquid mixer 2; and two fixed-bed reactors, a first fixed-bed reactor 31 and a second fixed-bed reactor 32. The gas-liquid mixer 2 is provided with at least a gas inlet, a liquid inlet, and a liquid outlet. The liquid outlet of the visbreaking device 1 is connected to the liquid inlet of the gas-liquid mixer 2 through a pipeline, and the liquid outlet of the gas-liquid mixer 2 is connected to the inlets of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 via a first feed valve and a second feed valve respectively through pipelines.

[0095] The outlet pipes of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 are provided with a first discharge valve and a second discharge valve respectively.

[0096] A pipeline with a first one-way valve and a pipeline with a second one-way valve are connected before the discharge valves of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 respectively, and are connected behind the feed valves of the second fixed-bed reactor 32 and the first fixed-bed reactor 31 respectively in the back, so that materials can be introduced from the outlet of one fixed-bed reactor to the inlet of the other reactor.

Example 4

[0097] This example provides a device for viscosity-reducing and upgrading of low-grade heavy oil, of which the structural schematic diagram is shown in FIG. 4. As can be seen from FIG. 4, the device includes: a visbreaking device 1; a gas-liquid mixer 2; a fixed-bed reactor 3; and a fractionation column 4. The gas-liquid mixer 2 is provided with at least a gas inlet, a liquid inlet and a liquid outlet. The liquid outlet of the visbreaking device 1 is connected to the liquid inlet of the fractionation column 4 through a pipeline. The light distillate oil outlet of the fractionation column 4 is connected to the liquid inlet of the gas-liquid mixer 2 through a pipeline, and the liquid outlet of the gas-liquid mixer 2 is connected to the inlet of the fixed-bed reactor 3 through a pipeline.

[0098] In this example, the device further comprises a storage tank for the viscosity-reduced and upgraded oil (not shown in the figure), and the heavy distillate oil outlet of the fractionation column 4 and the outlet of the fixed-bed reactor 3 are respectively connected to the storage tank for the viscosity-reduced and upgraded oil through pipelines.

Example 5

[0099] This example provides a device for viscosity-reducing and upgrading of low-grade heavy oil, of which the structural schematic diagram is shown in FIG. 5. As can be seen from FIG. 5, the device includes: a visbreaking device 1; a gas-liquid mixer 2; two fixed-bed reactors, a first fixed-bed reactor 31 and a second fixed-bed reactor 32, which are arranged in parallel; and a fractionation column 4. The gas-liquid mixer 2 is provided with at least a gas inlet, a liquid inlet and a liquid outlet. The liquid outlet of the visbreaking device 1 is connected to the liquid inlet of the fractionation column 4 through a pipeline. The light distillate oil outlet of the fractionation column 4 is connected to the liquid inlet of the gas-liquid mixer 2 through a pipeline, and the liquid outlet of the gas-liquid mixer 2 is connected to the inlets of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 via a first feed valve and a second feed valve respectively through pipelines.

[0100] In this example, the device further comprises a storage tank for the viscosity-reduced and upgraded oil (not shown in the figure), and the heavy distillate oil outlet of the fractionation column 4 and the outlets of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 are respectively connected to the storage tank for the viscosity-reduced and upgraded oil through pipelines.

Example 6

[0101] This example provides a device for viscosity-reducing and upgrading of low-grade heavy oil. of which the structural schematic diagram is shown in FIG. 6. As can be seen from FIG. 6, the device includes: a visbreaking device 1; a gas-liquid mixer 2; two fixed-bed reactors, a first fixed-bed reactor 31 and a second fixed-bed reactor 32; and a fractionation column 4. The gas-liquid mixer 2 is provided with at least a gas inlet, a liquid inlet and a liquid outlet. The liquid outlet of the visbreaking device 1 is connected to the liquid inlet of the fractionation column 4 through a pipeline. The light distillate oil outlet of the fractionation column 4 is connected to the liquid inlet of the gas-liquid mixer 2 through a pipeline, and the liquid outlet of the gas-liquid mixer 2 is connected to the inlets of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 via a first feed valve and a second feed valve respectively through pipelines.

[0102] The outlet pipes of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 are provided with a first discharge valve and a second discharge valve respectively.

[0103] A pipeline with a first one-way valve and a pipeline with a second one-way valve are connected before the discharge valves of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 respectively, and are connected behind the feed valves of the second fixed-bed reactor 32 and the first fixed-bed reactor 31 respectively in the back, so that materials can be introduced from the outlet of one fixed-bed reactor to the inlet of the other reactor.

[0104] In this example, the device further comprises a storage tank for the viscosity-reduced and upgraded oil (not shown in the figure), and the heavy distillate oil outlet of the fractionation column 4 and the outlets of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 are respectively connected to the storage tank for the viscosity-reduced and upgraded oil through pipelines.

Example 7

[0105] This example provides a device for viscosity-reducing and upgrading of low-grade heavy oil, of which the structural schematic diagram is shown in FIG. 7. As can be seen from FIG. 7, the device includes: a visbreaking device 1; and a fixed-bed reactor 3. The liquid outlet of the visbreaking device 1 is connected to the liquid inlet of the fixed-bed reactor 3 through a pipeline, and the outlet of the hydrogen storage tank is also connected to the liquid inlet of the fixed-bed reactor 3 through a pipeline.

Example 8

[0106] This example provides a device for viscosity-reducing and upgrading of low-grade heavy oil, of which the structural schematic diagram is shown in FIG. 8. As can be seen from FIG. 8, the device includes: a visbreaking device 1; and two fixed-bed reactors, a first fixed-bed reactor 31 and a second fixed-bed reactor 32, which are arranged in parallel. The liquid outlet of the visbreaking device 1 is connected to the inlets of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 via a first feed valve and a second feed valve respectively through pipelines.

Example 9

[0107] This example provides a device for viscosity-reducing and upgrading of low-grade heavy oil, of which the structural schematic diagram is shown in FIG. 9. As can be seen from FIG. 9, the device includes: a visbreaking device 1; and two fixed-bed reactors, a first fixed-bed reactor 31 and a second fixed-bed reactor 32. The liquid outlet of the visbreaking device 1 is connected to the inlets of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 via a first feed valve and a second feed valve respectively through pipelines.

[0108] The outlet pipes of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 are provided with a first discharge valve and a second discharge valve respectively.

[0109] A pipeline with a first one-way valve and a pipeline with a second one-way valve are connected before the discharge valves of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 respectively, and are connected behind the feed valves of the second fixed-bed reactor 32 and the first fixed-bed reactor 31 respectively in the back, so that materials can be introduced from the outlet of one fixed-bed reactor to the inlet of the other reactor.

Example 10

[0110] This example provides a device for viscosity-reducing and upgrading of low-grade heavy oil, of which the structural schematic diagram is shown in FIG. 10. As can be seen from FIG. 10, the device includes: a visbreaking device 1; a fixed-bed reactor 3; and a fractionation column 4. The liquid outlet of the visbreaking device 1 is connected to the liquid inlet of the fractionation column 4 through a pipeline. The light distillate oil outlet of the fractionation column 4 is connected to the inlet of the fixed-bed reactor 3 through a pipeline, and the outlet of the hydrogen storage tank is also connected to the inlet of the fixed-bed reactor 3 through a pipeline.

[0111] In this example, the device further comprises a storage tank for the viscosity-reduced and upgraded oil 5, and the heavy distillate oil outlet of the fractionation column 4 and the outlet of the fixed-bed reactor 3 are respectively connected to the storage tank for the viscosity-reduced and upgraded oil 5 through pipelines.

Example 11

[0112] This example provides a device for viscosity-reducing and upgrading of low-grade heavy oil, of which the structural schematic diagram is shown in FIG. 11. As can be seen from FIG. 11, the device includes: a visbreaking device 1; two fixed-bed reactors, a first fixed-bed reactor 31 and a second fixed-bed reactor 32, which are arranged in parallel; and a fractionation column 4; the liquid outlet of the visbreaking device 1 is connected to the liquid inlet of the fractionation column 4 through a pipeline. The light distillate oil outlet of the fractionation column 4 is connected to the inlets of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 via a first feed valve and a second feed valve respectively through pipelines.

[0113] In this example, the device further comprises a storage tank for the viscosity-reduced and upgraded oil (not shown in the figure), and the heavy distillate oil outlet of the fractionation column 4 and the outlets of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 are respectively connected to the storage tank for the viscosity-reduced and upgraded oil through pipelines.

Example 12

[0114] This example provides a device for viscosity-reducing and upgrading of low-grade heavy oil, of which the structural schematic diagram is shown in FIG. 12. As can be seen from FIG. 12, the device includes: a visbreaking device 1; two fixed-bed reactors, a first fixed-bed reactor 31 and a second fixed-bed reactor 32; and a fractionation column 4. The liquid outlet of the visbreaking device 1 is connected to the liquid inlet of the fractionation column 4 through a pipeline. The light distillate oil outlet of the fractionation column 4 is connected to the inlets of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 via a first feed valve and a second feed valve respectively through pipelines.

[0115] The outlet pipes of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 are provided with a first discharge valve and a second discharge valve respectively.

[0116] A pipeline with a first one-way valve and a pipeline with a second one-way valve are connected before the discharge valves of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 respectively, and are connected behind the feed valves of the second fixed-bed reactor 32 and the first fixed-bed reactor 31 respectively in the back, so that materials can be introduced from the outlet of one fixed-bed reactor to the inlet of the other reactor.

[0117] In this example, the device further comprises a storage tank for the viscosity-reduced and upgraded oil (not shown in the figure), and the heavy distillate oil outlet of the fractionation column 4 and the outlets of the first fixed-bed reactor 31 and the second fixed-bed reactor 32 are respectively connected to the storage tank for the viscosity-reduced and upgraded oil through pipelines.

Example 13

[0118] This example provides a method for viscosity-reducing and upgrading of low-grade heavy oil, wherein the method for viscosity-reducing and upgrading of low-grade heavy oil utilizes the device for viscosity-reducing and upgrading of low-grade heavy oil provided in Example 1, and the method includes the following steps:

[0119] In this example, the low-grade heavy oil is oil sand bitumen with a kinematic viscosity (80° C.) of 8520 cSt and an API degree of 8.3. Its properties are shown in Table 1 below.

[0120] As shown in FIG. 1, the oil sand bitumen enters the visbreaking device for visbreaking reaction. The operating process conditions are: a reaction temperature of 415° C., a reaction pressure of 0.6 MPa, a residence time of 5 minutes, a mass conversion rate of visbreaking reaction of 20%, and the mass content of toluene insolubles in the produced oil of 0.05%.

[0121] The produced oil and hydrogen are mixed in a gas-liquid mixer to form a hydrogen-oil mixture in liquid state. The hydrogen-oil mixture enters a fixed-bed reactor filled with a hydrogenation catalyst for hydrogenation. The hydrogenation catalyst contains Ni and Mo. The hydrogenation catalyst has a pore volume of 1.0 mL/g and a specific surface area of 160 m.sup.2/g, and the volume of pores with a pore diameter greater than 50 nm in the hydrogenation catalyst accounts for 32% of the total pore volume. The pores of the hydrogenation catalyst present a bimodal distribution. The most probable pore diameter of the small pores is 20 nm, and the most probable pore diameter of the large pores is 800 nm. The hydrogenation catalyst is a sulfided catalyst. The process conditions of fixed-bed hydrogenation reaction are: a reaction pressure of 4.0 MPa; a reaction temperature of 320° C.; and a liquid hourly volumetric space velocity of 4.0 h.sup.−1. After the hydrogenation reaction is completed, a viscosity-reduced and upgraded oil with a kinematic viscosity (20° C.) of 324 cSt and an API degree of 19.5 is obtained. The properties of the viscosity-reduced and upgraded oil are shown in Table 1.

[0122] Table 1

TABLE-US-00001 TABLE 1 Example 13 Raw material Product Kinematic viscosity, cSt 8520 (80° C.) 324 (20° C.) API degree 8.3 19.5 Olefin, % — 0.02 CCR, % 17.8 18.0 Ni, μg/g 95.5 78.6 V, μg/g 255.6 211.9 Visbreaking Reaction temperature, ° C. 415 Reaction pressure, MPa 0.6 Residence time, min 5 Fixed-bed Reaction pressure, MPa 4.0 hydrogena- Reaction temperature, ° C. 320 tion Liquid hourly volumetric 4.0 space velocity, h.sup.−1

Example 14

[0123] This example provides a method for viscosity-reducing and upgrading of low-grade heavy oil, wherein the method for viscosity-reducing and upgrading of low-grade heavy oil utilizes the device for viscosity-reducing and upgrading of low-grade heavy oil provided in Example 2, and the method includes the following steps:

[0124] In this example, the low-grade heavy oil is heavy oil with a kinematic viscosity (80° C.) of 7668 cSt and an API degree of 8.1. Its properties are shown in Table 2 below.

[0125] As shown in FIG. 2, the heavy oil enters the visbreaking device for visbreaking reaction. The operating process conditions are: a reaction temperature of 435° C., a reaction pressure of 0.6 MPa, a residence time of 10 minutes, a mass conversion rate of visbreaking reaction of 40%, and the mass content of toluene insolubles in the produced oil of 0.03%.

[0126] The produced oil and hydrogen are mixed in a gas-liquid mixer to form a hydrogen-oil mixture in liquid state. The hydrogen-oil mixture enters a fixed-bed reactor filled with a hydrogenation catalyst for hydrogenation. The hydrogenation catalyst contains Co and Mo. The hydrogenation catalyst has a pore volume of 1.2 mL/g and a specific surface area of 132 m.sup.2/g, and the volume of pores with a pore diameter greater than 50 mu in the hydrogenation catalyst accounts for 44% of the total pore volume. The pores of the hydrogenation catalyst present a trimodal distribution. The most probable pore diameters are 24 nm, 280 nm, 1160 nm, respectively. The hydrogenation catalyst is a sulfided catalyst. The process conditions of fixed-bed hydrogenation reaction are: a reaction pressure of 8.0 MPa, a reaction temperature of 360° C., and a liquid hourly volumetric space velocity of 2.0 h.sup.−1. After the hydrogenation reaction is completed, a viscosity-reduced and upgraded oil with a kinematic viscosity (20° C.) of 66 cSt and an API degree of 19.6 is obtained. The properties of the viscosity-reduced and upgraded oil are shown in Table 2.

[0127] In this example, the operation steps of the fixed-bed reactors are as follows:

[0128] (S1) closing the feed valve of the second fixed-bed reactor, opening the feed valve of the first fixed-bed reactor, and using the first fixed-bed reactor for hydrogenation reaction;

[0129] (S2) when the hydrogenation catalyst in the first fixed-bed reactor is deactivated, opening the feed valve of the second fixed-bed reactor, using the second fixed-bed reactor for hydrogenation reaction, closing the feed valve of the first fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the first fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst;

[0130] (S3) when the hydrogenation catalyst in the second fixed-bed reactor is deactivated, opening the feed valve of the first fixed-bed reactor, using the first fixed-bed reactor for hydrogenation reaction, closing the feed valve of the second fixed-bed reactor, and replacing the hydrogenation catalyst in the second fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst;

[0131] (S4) repeating steps (S1) to (S3) for hydrogenation reaction.

TABLE-US-00002 TABLE 2 Example 14 Raw material Product Kinematic viscosity, cSt 7668 (80° C.) 66 (20° C.) API degree 8.1 19.6 Olefin, % — 0.01 CCR, % 16.7 16.8 Ni, μg/g 76.0 64.9 V, μg/g 482.3 430.6 Visbreaking Reaction 435 temperature, ° C. Reaction pressure, MPa 0.6 Residence time, min 10 fixed-bed Reaction pressure, MPa 8.0 hydrogenation Reaction 360 temperature, ° C. Liquid hourly 2.0 volumetric space velocity, h.sup.−1

Example 15

[0132] This example provides a method for viscosity-reducing and upgrading of low-grade heavy oil, wherein the method for viscosity-reducing and upgrading of low-grade heavy oil utilizes the device for viscosity-reducing and upgrading of low-grade heavy oil provided in Example 3, and the method includes the following steps:

[0133] In this example, the low-grade heavy oil is vacuum residuum with a kinematic viscosity (80° C.) of 4457 cSt and an API degree of 7.8. Its properties are shown in Table 3 below.

[0134] As shown in FIG. 3, the vacuum residuum enters the visbreaking device for visbreaking reaction. The operating process conditions are: a reaction temperature of 420° C., a reaction pressure of 0.8114 Pa, a residence time of 20 minutes, a mass conversion rate of visbreaking reaction of 30%, and the mass content of toluene insolubles in the produced oil of 0.02%;

[0135] The produced oil and hydrogen are mixed in a gas-liquid mixer to form a hydrogen-oil mixture in liquid state. The hydrogen-oil mixture enters a fixed-bed reactor filled with a hydrogenation catalyst for hydrogenation. The hydrogenation catalyst contains Co and W. The hydrogenation catalyst has a pore volume of 1.1 mL/g and a specific surface area of 151 m.sup.2/g, and the volume of pores with a pore diameter greater than 50 nm in the hydrogenation catalyst accounts for 38% of the total pore volume. The pores of the hydrogenation catalyst present a bimodal distribution. The most probable pore diameter of the small pores is 30 nm, and the most probable pore diameter of the large pores is 1086 nm. The hydrogenation catalyst is a sulfided catalyst. The process conditions of fixed-bed hydrogenation reaction are: a reaction pressure of 6.0 MPa, a reaction temperature of 340° C., and a liquid hourly volumetric space velocity of 6.0 h.sup.−1. After the hydrogenation reaction is completed, a viscosity-reduced and upgraded oil with a kinematic viscosity (20° C.) of 158 cSt and an API degree of 19.3 is obtained. The properties of the viscosity-reduced and upgraded oil are shown in Table 3.

[0136] In this example, the operation steps of the fixed-bed reactor are as follows:

[0137] S1) in the initial stage of the reaction, using the two fixed-bed reactors together, the hydrogen-oil mixture first entering one of the fixed-bed reactors (such as the first fixed-bed reactor), and then entering the other fixed-bed reactor (such as the second fixed-bed reactor) through the pipeline with a one-way valve for hydrogenation reaction;

[0138] S2) after a period of reaction, when the activity of the hydrogenation catalyst in the first fixed-bed reactor is close to the mid-to-late stage, changing the flow direction of the hydrogen-oil mixture so that the hydrogen-oil mixture first enters the second fixed-bed reactor, and then enters the first fixed-bed reactor through the pipeline with a one-way valve;

[0139] S3) when the hydrogenation catalyst in the first fixed-bed reactor is in the deactivation stage, closing the feed valve of the first fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the first fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst, and at this time, the hydrogen-oil mixture only entering the second fixed-bed reactor;

[0140] S4) after the catalyst in the first fixed-bed reactor is replaced, the hydrogen-oil mixture first entering the second fixed-bed reactor, and then entering the first fixed-bed reactor where the catalyst has been replaced, through the pipeline with a one-way valve;

[0141] S5) when the hydrogenation catalyst in the second fixed-bed reactor is in the deactivation stage, closing the feed valve of the second fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the second fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst, and at this time, the hydrogen-oil mixture only entering the first fixed-bed reactor; and

[0142] S6) after the catalyst in the second fixed-bed reactor is replaced, repeating steps (S1) to (S5) for hydrogenation reaction.

TABLE-US-00003 TABLE 3 Example 15 Raw material Product Kinematic viscosity, cSt 4457 (80° C.) 158 (20° C.) API degree 7.8 19.3 Olefin, % — 0.01 CCR, % 19.2 19.2 Ni, μg/g 88.6 66.1 V, μg/g 182.4 153.7 Visbreaking Reaction 420 temperature, ° C. Reaction pressure, MPa 0.8 Residence time, min 20 fixed-bed Reaction pressure, MPa 6.0 hydrogenation Reaction 340 temperature, ° C. Liquid hourly 6.0 volumetric space velocity, h.sup.−1

Example 16

[0143] This example provides a method for viscosity-reducing and upgrading of low-grade heavy oil, wherein the method for viscosity-reducing and upgrading of low-grade heavy oil utilizes the device for viscosity-reducing and upgrading of low-grade heavy oil provided in Example 4, and the method includes the following steps:

[0144] In this example, the low-grade heavy oil is oil sand bitumen with a kinematic viscosity (80° C.) of 8510 cSt and an API degree of 8.4;

[0145] As shown in FIG. 4, the oil sand bitumen enters the visbreaking device for visbreaking reaction. The operating process conditions are: a reaction temperature of 414° C., a reaction pressure of 0.6 MPa, a residence time of 4.5 minutes, a mass conversion rate of visbreaking reaction of 18%, and the mass content of toluene insolubles in the produced oil of 0.04%.

[0146] The produced oil is cut at 500° C. in a fractionation column to obtain a light distillate oil and a heavy distillate oil. The light distillate oil and hydrogen are mixed in a gas-liquid mixer to form a hydrogen-oil mixture in liquid state, and the hydrogen-oil mixture enters a fixed-bed reactor filled with a hydrogenation catalyst for hydrogenation reaction. The hydrogenation catalyst contains Ni and Mo. The hydrogenation catalyst contains Ni and Mo. The hydrogenation catalyst has a pore volume of 1.05 mL/g and a specific surface area of 162 m.sup.2/g, and the volume of pores with a pore diameter greater than 50 nm in the hydrogenation catalyst accounts for 30% of the total pore volume. The pores of the hydrogenation catalyst present a bimodal distribution. The most probable pore diameter of the small pores is 22 nm, and the most probable pore diameter of the large pores is 750 nm. The hydrogenation catalyst is a sulfided catalyst. The process conditions of fixed-bed hydrogenation reaction are: a reaction pressure of 4.2 MPa, a reaction temperature of 325° C., and a liquid hourly volumetric space velocity of 4.3 h.sup.−1. After the hydrogenation reaction, a hydrogenated liquid product is obtained. The hydrogenated liquid product is then mixed with the heavy distillate oil, to obtain a viscosity-reduced and upgraded oil with a kinematic viscosity (20° C.) of 320 cSt and an API degree of 19.6.

Example 17

[0147] This example provides a method for viscosity-reducing and upgrading of low-grade heavy oil, wherein the method for viscosity-reducing and upgrading of low-grade heavy oil utilizes the device for viscosity-reducing and upgrading of low-grade heavy oil provided in Example 5, and the method includes the following steps:

[0148] In this example, the low-grade heavy oil is heavy oil with a kinematic viscosity (80° C.) of 7638 cSt and an API degree of 8.2.

[0149] As shown in FIG. 5, the heavy oil enters the visbreaking device for visbreaking reaction. The operating process conditions are: a reaction temperature of 436° C., a reaction pressure of 0.6 MPa, a residence time of 9 minutes, a mass conversion rate of visbreaking reaction of 40%, and the mass content of toluene insolubles in the produced oil of 0.03%.

[0150] The produced oil is cut at 480° C. in a fractionation column to obtain a light distillate oil and a heavy distillate oil. The light distillate oil and hydrogen are mixed in a gas-liquid mixer to form a hydrogen-oil mixture in liquid state. The hydrogenation catalyst contains Co and Mo. The hydrogenation catalyst has a pore volume of 1.1 mL/g and a specific surface area of 146 m.sup.2/g, and the volume of pores with a pore diameter greater than 50 nm in the hydrogenation catalyst accounts for 43% of the total pore volume. The pores of the hydrogenation catalyst are distributed in a trimodal pattern. The most probable pore diameters are 25 nm, 290 nm, 1245 nm, respectively. The hydrogenation catalyst is a sulfided catalyst. The process conditions of fixed-bed hydrogenation reaction are: a reaction pressure of 8.2 MPa, a reaction temperature of 358° C., and liquid hourly volumetric space velocity of 2.2 h.sup.−1. After the hydrogenation reaction, a hydrogenated liquid product is obtained. The hydrogenated liquid product is then mixed with the heavy distillate oil, to obtain a viscosity-reduced and upgraded oil with a kinematic viscosity (20° C.) of 64 cSt and an API degree of 19.5.

[0151] In this example, the operation steps of the fixed-bed reactor are as follows:

[0152] (S1) closing the feed valve of the second fixed-bed reactor, opening the feed valve of the first fixed-bed reactor, and using the first fixed-bed reactor for hydrogenation reaction;

[0153] (S2) when the hydrogenation catalyst in the first fixed-bed reactor is deactivated, opening the feed valve of the second fixed-bed reactor, using the second fixed-bed reactor for hydrogenation reaction, closing the feed valve of the first fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the first fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst;

[0154] (S3) when the hydrogenation catalyst in the second fixed-bed reactor is deactivated, opening the feed valve of the first fixed-bed reactor, using the first fixed-bed reactor for hydrogenation reaction, closing the feed valve of the second fixed-bed reactor, and replacing the hydrogenation catalyst in the second fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst;

[0155] (S4) repeating steps (S1) to (S3) for hydrogenation reaction.

Example 18

[0156] This example provides a method for viscosity-reducing and upgrading of low-grade heavy oil, wherein the method for viscosity-reducing and upgrading of low-grade heavy oil utilizes the device for viscosity-reducing and upgrading of low-grade heavy oil provided in Example 6, and the method includes the following steps:

[0157] In this example, the low-grade heavy oil is vacuum residuum with a kinematic viscosity (80° C.) of 5455 cSt and an API degree of 7.7.

[0158] As shown in FIG. 6, the vacuum residuum enters the visbreaking device for visbreaking reaction. The operating process conditions are: a reaction temperature of 418° C., a reaction pressure of 0.8 MPa, a residence time of 23 minutes, a mass conversion rate of visbreaking reaction of 31%, and the mass content of toluene insolubles in the produced oil of 0.03%.

[0159] The produced oil is cut at 520° C. in a fractionation column to obtain a light distillate oil and a heavy distillate oil. The light distillate oil and hydrogen are mixed in a gas-liquid mixer to form a hydrogen-oil mixture in liquid state. The hydrogenation catalyst contains Co and W. The hydrogenation catalyst contains Co and W. The hydrogenation catalyst has a pore volume of 1.2 mL/g and a specific surface area of 139 m.sup.2/g, and the volume of pores with a pore diameter greater than 50 nm in the hydrogenation catalyst accounts for 35% of the total pore volume. The pores of the hydrogenation catalyst present a bimodal distribution. The most probable pore diameter of the small pores is 33 nm, and the most probable pore diameter of the large pores is 1368 nm. The hydrogenation catalyst is a sulfided catalyst. The process conditions of fixed-bed hydrogenation reaction are: a reaction pressure of 6.6 MPa, a reaction temperature of 344° C., and a liquid hourly volumetric space velocity of 6.7 h.sup.−1. After the hydrogenation reaction, a hydrogenated liquid product is obtained. The hydrogenated liquid product is then mixed with the heavy distillate oil, to obtain a viscosity-reduced and upgraded oil with a kinematic viscosity (20° C.) of 167 cSt and an API degree of 19.2.

[0160] In this example, the operation steps of the fixed-bed reactor are as follows:

[0161] S1) in the initial stage of the reaction, using the two fixed-bed reactors together, the hydrogen-oil mixture first entering one of the fixed-bed reactors (such as the first fixed-bed reactor), and then entering the other fixed-bed reactor (such as the second fixed-bed reactor) through the pipeline with a one-way valve for hydrogenation reaction;

[0162] S2) after a period of reaction, when the activity of the hydrogenation catalyst in the first fixed-bed reactor is close to the mid-to-late stage, changing the flow direction of the hydrogen-oil mixture so that the hydrogen-oil mixture first enters the second fixed-bed reactor, and then enters the first fixed-bed reactor through the pipeline with a one-way valve;

[0163] S3) when the hydrogenation catalyst in the first fixed-bed reactor is in the deactivation stage, closing the feed valve of the first fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the first fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst, and at this time, the hydrogen-oil mixture only entering the second fixed-bed reactor;

[0164] S4) after the catalyst in the first fixed-bed reactor is replaced, the hydrogen-oil mixture first entering the second fixed-bed reactor, and then entering the first fixed-bed reactor where the catalyst has been replaced, through the pipeline with a one-way valve;

[0165] S5) when the hydrogenation catalyst in the second fixed-bed reactor is in the deactivation stage, closing the feed valve of the second fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the second fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst, and at this time, the hydrogen-oil mixture only entering the first fixed-bed reactor; and

[0166] S6) after the catalyst in the second fixed-bed reactor is replaced, repeating steps (S1) to (S5) for hydrogenation reaction.

Example 19

[0167] This example provides a method for viscosity-reducing and upgrading of low-grade heavy oil, wherein the method for viscosity-reducing and upgrading of low-grade heavy oil utilizes the device for viscosity-reducing and upgrading of low-grade heavy oil provided in Example 7, and the method includes the following steps:

[0168] In this example, the low-grade heavy oil is oil sand bitumen with a kinematic viscosity (80° C.) of 9652 cSt and an API degree of 7.9. Its properties are shown in Table 4;

[0169] As shown in FIG. 7, the oil sand bitumen enters the visbreaking device for visbreaking reaction. The operating process conditions are: a reaction temperature of 417° C., a reaction pressure of 0.5 MPa, a residence time of 4 minutes, a mass conversion rate of visbreaking reaction of 22%, and the mass content of toluene insolubles in the produced oil of 0.06%.

[0170] The produced oil and hydrogen are mixed to form a hydrogen-oil mixture in gas-liquid state. The hydrogen-oil mixture enters a fixed-bed reactor filled with a hydrogenation catalyst for hydrogenation. The hydrogenation catalyst contains Ni and Mo. The hydrogenation catalyst has a pore volume of 1.1 mL/g and a specific surface area of 173 m.sup.2/g, and the volume of pores with a pore diameter greater than 50 nm in the hydrogenation catalyst accounts for 34% of the total pore volume. The pores of the hydrogenation catalyst present a bimodal distribution. The most probable pore diameter of the small pores is 24 nm, and the most probable pore diameter of the large pores is 930 nm. The hydrogenation catalyst is a sulfided catalyst. The process conditions of fixed-bed hydrogenation reaction are: a reaction pressure of 4.8 MPa, a reaction temperature of 346° C., a liquid hourly volumetric space velocity of 5.2 h.sup.−1, and a volume ratio of hydrogen to oil of 1200. After the hydrogenation reaction is completed, a viscosity-reduced and upgraded oil with a kinematic viscosity (20° C.) of 297 cSt and an API degree of 19.5 is obtained. The properties of the viscosity-reduced and upgraded oil are shown in Table 4.

TABLE-US-00004 TABLE 4 Example 19 Raw material Product Kinematic viscosity, cSt 9652 (80° C.) 297 (20° C.) API degree 7.9 19.5 Olefin, % — 0.02 CCR, % 17.8 18.0 Ni, μg/g 95.5 78.6 V, μg/g 255.6 211.9 Visbreaking Reaction 417 temperature, ° C. Reaction pressure, MPa 0.5 Residence time, min 4 fixed-bed Reaction pressure, MPa 4.8 hydrogenation Reaction 346 temperature, ° C. Liquid hourly 5.2 volumetric space velocity, h.sup.−1 Volume ratio of 1200 hvdrogen to oil

Example 20

[0171] This example provides a method for viscosity-reducing and upgrading of low-grade heavy oil, wherein the method for viscosity-reducing and upgrading of low-grade heavy oil utilizes the device for viscosity-reducing and upgrading of low-grade heavy oil provided in Example 8, and the method includes the following steps:

[0172] In this example, the low-grade heavy oil is heavy oil with a kinematic viscosity (80° C.) of 9563 cSt and an API degree of 8.0, its properties are shown in Table 5 below.

[0173] As shown in FIG. 8, the heavy oil enters the visbreaking device for visbreaking reaction. The operating process conditions are: a reaction temperature of 439° C., a reaction pressure of 0.6 MPa, a residence time of 8 minutes, a mass conversion rate of visbreaking reaction of 42%, and the mass content of toluene insolubles in the produced oil of 0.04%.

[0174] The produced oil and hydrogen are mixed to form a hydrogen-oil mixture in gas-liquid state. The hydrogen-oil mixture enters a fixed-bed reactor filled with a hydrogenation catalyst for hydrogenation. The hydrogenation catalyst contains Co and Mo. The hydrogenation catalyst has a pore volume of 1.4 mL/g and a specific surface area of 118 m.sup.2/g, and the volume of pores with a pore diameter greater than 50 nm in the hydrogenation catalyst accounts for 46% of the total pore volume. The pores of the hydrogenation catalyst present a trimodal distribution. The most probable pore diameters are 21 nm, 260 nm, 1050 nm, respectively. The hydrogenation catalyst is a sulfided catalyst. The process conditions of fixed-bed hydrogenation reaction are: a reaction pressure of 9.2 MPa, a reaction temperature of 373° C., a liquid hourly volumetric space velocity of 2.8 h.sup.−1, and a volume ratio of hydrogen to oil of 280. After the hydrogenation reaction is completed, a viscosity-reduced and upgraded oil with a kinematic viscosity (20° C.) of 59 cSt and an API degree of 19.6 is obtained. The properties of the viscosity-reduced and upgraded oil are shown in Table 5.

[0175] In this example, the operation steps of the fixed-bed reactors are as follows:

[0176] (S1) closing the feed valve of the second fixed-bed reactor, opening the feed valve of the first fixed-bed reactor, and using the first fixed-bed reactor for hydrogenation reaction;

[0177] (S2) when the hydrogenation catalyst in the first fixed-bed reactor is deactivated, opening the feed valve of the second fixed-bed reactor, using the second fixed-bed reactor for hydrogenation reaction, closing the feed valve of the first fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the first fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst;

[0178] (S3) when the hydrogenation catalyst in the second fixed-bed reactor is deactivated, opening the feed valve of the first fixed-bed reactor, using the first fixed-bed reactor for hydrogenation reaction, closing the feed valve of the second fixed-bed reactor, and replacing the hydrogenation catalyst in the second fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst;

[0179] (S4) repeating steps (S1) to (S3) for hydrogenation reaction.

TABLE-US-00005 TABLE 5 Example 20 Raw material Product Kinematic viscosity, cSt 9563 (80° C.) 59 (20° C.) API degree 8.0 19.6 Olefin, % — 0.01 CCR, % 16.7 16.8 Ni, μg/g 76.0 64.9 V, μg/g 482.3 430.6 Visbreaking Reaction 439 temperature, ° C. Reaction pressure, MPa 0.6 Residence time, min 8 fixed-bed Reaction pressure, MPa 9.2 hydrogenation Reaction 373 temperature, ° C. Liquid hourly 2.8 volumetric space velocity, h.sup.−1 Volume ratio of 280 hydrogen to oil

Example 21

[0180] This example provides a method for viscosity-reducing and upgrading of low-grade heavy oil, wherein the method for viscosity-reducing and upgrading of low-grade heavy oil utilizes the device for viscosity-reducing and upgrading of low-grade heavy oil provided in Example 9, and the method includes the following steps:

[0181] In this example, the low-grade heavy oil is vacuum residuum with a kinematic viscosity (80° C.) of 6369 cSt and an API degree of 7.8, Its properties are shown in Table 6.

[0182] As shown in FIG. 9, the vacuum residuum enters the visbreaking device for visbreaking reaction. The operating process conditions are: a reaction temperature of 426° C., a reaction pressure of 0.7 MPa, a residence time of 17 minutes, a mass conversion rate of visbreaking reaction of 30%, and the mass content of toluene insolubles in the produced oil of 0.04%;

[0183] The produced oil and hydrogen are mixed to form a hydrogen-oil mixture in gas-liquid state. The hydrogen-oil mixture enters a fixed-bed reactor filled with a hydrogenation catalyst for hydrogenation. The hydrogenation catalyst contains Co and W. The hydrogenation catalyst has a pore volume of 1.1 mL/g and a specific surface area of 153 m.sup.2/g, and the volume of pores with a pore diameter greater than 50 nm in the hydrogenation catalyst accounts for 39% of the total pore volume. The pores of the hydrogenation catalyst present a bimodal distribution. The most probable pore diameter of the small pores is 31 nm, and the most probable pore diameter of the large pores is 997 nm. The hydrogenation catalyst is a sulfided catalyst. The process conditions of fixed-bed hydrogenation reaction are: a reaction pressure of 7.2 MPa, a reaction temperature of 352° C., a liquid hourly volumetric space velocity of 7.6 h.sup.−1, and a volume ratio of hydrogen to oil of 600. After the hydrogenation reaction is completed, a viscosity-reduced and upgraded oil with a kinematic viscosity (20° C.) of 129 cSt and an API degree of 19.3 is obtained. The properties of the viscosity-reduced and upgraded oil are shown in Table 6.

[0184] In this example, the operation steps of the fixed-bed reactor are as follows:

[0185] S1) in the initial stage of the reaction, using the two fixed-bed reactors together, the hydrogen-oil mixture first entering one of the fixed-bed reactors (such as the first fixed-bed reactor), and then entering the other fixed-bed reactor (such as the second fixed-bed reactor) through the pipeline with a one-way valve for hydrogenation reaction;

[0186] S2) after a period of reaction, when the activity of the hydrogenation catalyst in the first fixed-bed reactor is close to the mid-to-late stage, changing the flow direction of the hydrogen-oil mixture so that the hydrogen-oil mixture first enters the second fixed-bed reactor, and then enters the first fixed-bed reactor through the pipeline with a one-way valve;

[0187] S3) when the hydrogenation catalyst in the first fixed-bed reactor is in the deactivation stage, closing the feed valve of the first fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the first fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst, and at this time, the hydrogen-oil mixture only entering the second fixed-bed reactor;

[0188] S4) after the catalyst in the first fixed-bed reactor is replaced, the hydrogen-oil mixture first entering the second fixed-bed reactor, and then entering the first fixed-bed reactor where the catalyst has been replaced, through the pipeline with a one-way valve;

[0189] S5) when the hydrogenation catalyst in the second fixed-bed reactor is in the deactivation stage, closing the feed valve of the second fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the second fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst, and at this time, the hydrogen-oil mixture only entering the first fixed-bed reactor; and

[0190] S6) after the catalyst in the second fixed-bed reactor is replaced, repeating steps (S1) to (S5) for hydrogenation reaction.

TABLE-US-00006 TABLE 6 Example 21 Raw material Product Kinematic viscosity, cSt 6369 (80° C.) 129 (20° C.) API degree 7.8 19.3 Olefin, % — 0.01 CCR, % 19.2 19.2 Ni, μg/g 88.6 66.1 V, μg/g 182.4 153.7 Visbreaking Reaction 426 temperature, ° C. Reaction pressure, MPa 0.7 Residence time, min 17 fixed-bed Reaction pressure, MPa 7.2 hydrogenation Reaction 352 temperature, ° C. Liquid hourly 7.6 volumetric space velocity, h.sup.−1 Volume ratio of 600 hydrogen to oil

Example 22

[0191] This example provides a method for viscosity-reducing and upgrading of low-grade heavy oil, wherein the method for viscosity-reducing and upgrading of low-grade heavy oil utilizes the device for viscosity-reducing and upgrading of low-grade heavy oil provided in Example 10, and the method includes the following steps:

[0192] In this example, the low-grade heavy oil is oil sand bitumen with a kinematic viscosity (80° C.) of 1048 cSt and an API degree of 8.1.

[0193] As shown in FIG. 10, the oil sand bitumen enters the visbreaking device for visbreaking reaction. The operating process conditions are: a reaction temperature of 418° C., a reaction pressure of 0.8 MPa, a residence time of 7 minutes, a mass conversion rate of visbreaking reaction of 27%, and the mass content of toluene insolubles in the produced oil of 0.07%.

[0194] The produced oil is cut at 500° C. in the fractionation column to obtain a light distillate oil and a heavy distillate oil. The light distillate oil and hydrogen are mixed to form a hydrogen-oil mixture in gas-liquid state, and the hydrogen-oil mixture enters a fixed-bed reactor filled with a hydrogenation catalyst for hydrogenation reaction. The hydrogenation catalyst contains Ni and Mo. The hydrogenation catalyst has a pore volume of 1.3 mL/g and a specific surface area of 144 m.sup.2/g, and the volume of pores with a pore diameter greater than 50 nm in the hydrogenation catalyst accounts for 37% of the total pore volume. The pores of the hydrogenation catalyst present a bimodal distribution. The most probable pore diameter of the small pores is 29 nm, and the most probable pore diameter of the large pores is 990 nm. The hydrogenation catalyst is a sulfided catalyst. The process conditions of fixed-bed hydrogenation reaction are: a reaction pressure of 5.6 MPa, a reaction temperature of 338° C., a liquid hourly volumetric space velocity of 4.9 h.sup.−1, and a volume ratio of hydrogen to oil of 1280. After the hydrogenation reaction, a hydrogenated liquid product is obtained. The hydrogenated liquid product is then mixed with the heavy distillate oil, to obtain a viscosity-reduced and upgraded oil with a kinematic viscosity (20° C.) of 308 cSt and an API degree of 19.8.

Example 23

[0195] This example provides a method for viscosity-reducing and upgrading of low-grade heavy oil, wherein the method for viscosity-reducing and upgrading of low-grade heavy oil utilizes the device for viscosity-reducing and upgrading of low-grade heavy oil provided in Example 11, and the method includes the following steps:

[0196] In this example, the low-grade heavy oil is heavy oil with a kinematic viscosity (80° C.) of 8126 cSt and an API degree of 8.2.

[0197] As shown in FIG. 11, the heavy oil enters the visbreaking device for visbreaking reaction. The operating process conditions are: a reaction temperature of 427° C., a reaction pressure of 0.6 MPa, a residence time of 13 minutes, a mass conversion rate of visbreaking reaction of 37%, and the mass content of toluene insolubles in the produced oil of 0.03%.

[0198] The produced oil is cut at 480° C. in a fractionation column to obtain a light distillate oil and a heavy distillate oil. The light distillate oil and hydrogen are mixed to form a hydrogen-oil mixture in gas-liquid state, and the hydrogen-oil mixture enters a fixed-bed reactor filled with a hydrogenation catalyst for hydrogenation. The hydrogenation catalyst contains Co and Mo. The hydrogenation catalyst has a pore volume of 1.3 mL/g and a specific surface area of 125 m.sup.2/g, and the volume of pores with a pore diameter greater than 50 nm in the hydrogenation catalyst accounts for 41% of the total pore volume. The pores of the hydrogenation catalyst present a trimodal distribution. The most probable pore diameters are 22 nm, 215 nm, 1363 nm, respectively. The hydrogenation catalyst is a sulfided catalyst. The process conditions of fixed-bed hydrogenation reaction are: a reaction pressure of 9.6 MPa, a reaction temperature of 382° C., a liquid hourly volumetric space velocity of 4.1 h.sup.−1, and a volume ratio of hydrogen to oil of 270. After the hydrogenation reaction, a hydrogenated liquid product is obtained. The hydrogenated liquid product is then mixed with the heavy distillate oil, to obtain a viscosity-reduced and upgraded oil with a kinematic viscosity (20° C.) of 48 cSt and an API degree of 19.8.

[0199] In this example, the operation steps of the fixed-bed reactors are as follows:

[0200] (S1) closing the feed valve of the second fixed-bed reactor, opening the feed valve of the first fixed-bed reactor, and using the first fixed-bed reactor for hydrogenation reaction;

[0201] (S2) when the hydrogenation catalyst in the first fixed-bed reactor is deactivated, opening the feed valve of the second fixed-bed reactor, using the second fixed-bed reactor for hydrogenation reaction, closing the feed valve of the first fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the first fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst;

[0202] (S3) when the hydrogenation catalyst in the second fixed-bed reactor is deactivated, opening the feed valve of the first fixed-bed reactor, using the first fixed-bed reactor for hydrogenation reaction, closing the feed valve of the second fixed-bed reactor, and replacing the hydrogenation catalyst in the second fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst;

[0203] (S4) repeating steps (S1) to (S3) for hydrogenation reaction.

Example 24

[0204] This example provides a method for viscosity-reducing and upgrading of low-grade heavy oil, wherein the method for viscosity-reducing and upgrading of low-grade heavy oil utilizes the device for viscosity-reducing and upgrading of low-grade heavy oil provided in Example 12, and the method includes the following steps:

[0205] In this example, the low-grade heavy oil is vacuum residuum with a kinematic viscosity (80° C.) of 5682 cSt and an API degree of 7.7.

[0206] As shown in FIG. 12, the vacuum residuum enters the visbreaking device for visbreaking reaction. The operating process conditions are: a reaction temperature of 424° C., a reaction pressure of 0.8 MPa, a residence time of 18 minutes, a mass conversion rate of visbreaking reaction of 33%, and the mass content of toluene insolubles in the produced oil of 0.02%;

[0207] The produced oil is cut at 520° C. in a fractionation column to obtain a light distillate oil and a heavy distillate oil. The light distillate oil and hydrogen are mixed to form a hydrogen-oil mixture in gas-liquid state, and the hydrogen-oil mixture enters a fixed-bed reactor filled with a hydrogenation catalyst for hydrogenation. The hydrogenation catalyst contains Co and W. The hydrogenation catalyst has a pore volume of 1.2 mL/g and a specific surface area of 147 m.sup.2/g, and the volume of pores with a pore diameter greater than 50 nm in the hydrogenation catalyst accounts for 36% of the total pore volume. The pores of the hydrogenation catalyst present a bimodal distribution. The most probable pore diameter of the small pores is 32 nm, and the most probable pore diameter of the large pores is 1368 nm. The hydrogenation catalyst is a sulfided catalyst. The process conditions of fixed-bed hydrogenation reaction are: a reaction pressure of 6.8 MPa, a reaction temperature of 348° C., a liquid hourly volumetric space velocity of 6.6 h.sup.−1, and a volume ratio of hydrogen to oil of 660. After the hydrogenation reaction, a hydrogenated liquid product is obtained. The hydrogenated liquid product is mixed with the heavy distillate oil, to obtain a viscosity-reduced and upgraded oil with a kinematic viscosity (20° C.) of 140 cSt and an API degree of 19.2.

[0208] In this example, the operation steps of the fixed-bed reactor are as follows:

[0209] S1) in the initial stage of the reaction, using the two fixed-bed reactors together, the hydrogen-oil mixture first entering one of the fixed-bed reactors (such as the first fixed-bed reactor), and then entering the other fixed-bed reactor (such as the second fixed-bed reactor) through the pipeline with a one-way valve for hydrogenation reaction;

[0210] S2) after a period of reaction, when the activity of the hydrogenation catalyst in the first fixed-bed reactor is close to the mid-to-late stage, changing the flow direction of the hydrogen-oil mixture so that the hydrogen-oil mixture first enters the second fixed-bed reactor, and then enters the first fixed-bed reactor through the pipeline with a one-way valve;

[0211] S3) when the hydrogenation catalyst in the first fixed-bed reactor is in the deactivation stage, closing the feed valve of the first fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the first fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst, and at this time, the hydrogen-oil mixture only entering the second fixed-bed reactor;

[0212] S4) after the catalyst in the first fixed-bed reactor is replaced, the hydrogen-oil mixture first entering the second fixed-bed reactor, and then entering the first fixed-bed reactor where the catalyst has been replaced, through the pipeline with a one-way valve;

[0213] S5) when the hydrogenation catalyst in the second fixed-bed reactor is in the deactivation stage, closing the feed valve of the second fixed-bed reactor, and replacing the deactivated hydrogenation catalyst in the second fixed-bed reactor with the regenerated hydrogenation catalyst and/or fresh hydrogenation catalyst, and at this time, the hydrogen-oil mixture only entering the first fixed-bed reactor; and

[0214] S6) after the catalyst in the second fixed-bed reactor is replaced, repeating steps (S1) to (S5) for hydrogenation reaction.

[0215] The above descriptions are only specific examples of the present disclosure and cannot be used to limit the scope of implementation of the present disclosure. Therefore, the replacement of equivalent components, or equivalent changes and modifications made according to the scope of protection of the present disclosure, should still belong to the scope of this patent. In addition, it can be freely combined and used between the technical features and technical features, between technical features and technical inventions, and between technical inventions and technical inventions in the present disclosure.