Heavy oil slurry bed hydrogenation device and heavy oil slurry bed hydrogenation method

Abstract

The invention discloses a heavy oil slurry bed hydrogenation device, which comprises a pre-mixing unit, a preheating unit, a feeding unit and a slurry bed hydrogenation reaction unit which are sequentially communicated, and the pre-mixing unit is arranged to slow down the generation of a green coke precursor in heavy oil in the preheating process; the feeding unit is arranged at the bottom of the slurry bed hydrogenation reaction unit, and the feeding unit and the slurry bed hydrogenation reaction unit are completely separated, so that coking caused by the fact that a feeding structure arranged in a slurry bed reactor provides a green coke surface or possibly causes a flow dead zone can be avoided; a second hydrogen inlet and a hydrogen outlet are formed in the feeding unit, a mixture of heavy oil and hydrogen in the feeding unit does not make contact with second hydrogen, and deposition of a catalyst or green coke is avoided through the disturbance effect of hydrogen on the bottom of the slurry bed hydrogenation reaction unit; meanwhile, liquid phase circulation in the slurry bed reactor is enhanced, the inner wall of the slurry bed reactor is scoured, and green coke is further reduced.

Description

Technical Field

[0001] The invention relates to the field of heavy oil slurry bed hydrogenation, and relates to a heavy oil slurry bed hydrogenation device and a heavy oil slurry bed hydrogenation method. Background Art

[0002] Oil resources are becoming heavier and inferior, but the demand for clean and light energy is still growing, and the clean transformation of inferior energy is an inevitable trend in energy development. The existing fixed bed technology cannot meet the processing needs of heavy and inferior heavy oil, and the fluidized bed reactor also faces the problem of raw material applicability. Moreover, the fluidized bed reactor has a complex structure, a large amount of catalyst, and severe wear. The slurry bed reactor can theoretically process any heavy and inferior heavy oil, and the reactor has a simple structure. It has good application prospects in dealing with the problem of increasingly heavy and inferior oil resources.

[0003] At present, heavy oil slurry bed hydrogenation technology is still in the early stage of industrial promotion, but no good news has been reported. The coking process is one of the main factors restricting the application of slurry bed reactors in heavy oil hydrogenation. Therefore, how to effectively inhibit the coking process in the heavy oil slurry bed hydrogenation process is one of the key issues for the widespread application of slurry bed reactors in the heavy oil hydrogenation process.

[0004] Chinese patent document CN206418078U discloses a heavy oil hydrogenation external circulation slurry bed reactor, which is suitable for heavy oil hydrogenation process. By providing an external circulation of the reactor, the slurry forms a directional circulation flow in the reactor, thereby flushing the inner wall of the reactor, which can effectively inhibit the adhesion of solid particles, inhibit the generation of coking particles in the heavy oil reaction system, and effectively extend the operation cycle of the reactor. However, the fluid distributor of the bottom facility of the slurry bed reactor proposed in the utility model is a certain distance away from the bottom of the spherical head of the reactor, and may not be able to disturb the bottom of the spherical head well, so that there may be a flow dead zone, which is not conducive to inhibiting coking.

[0005] Chinese patent document CN211754831U discloses a heavy oil hydrogenation slurry bed reactor, which is suitable for heavy oil hydrogenation process. By arranging a guide tube and a baffle in the reactor, and arranging a slurry separator composed of inner and outer tubes on the top of the reactor, the slurry is continuously filled in the reactor, and there is no need to control the liquid level of the slurry phase, avoiding the problems of system emulsification and solid impurity enrichment at the gas-liquid main phase interface at the liquid level, thereby achieving the purpose of long-term continuous and stable operation. However, the slurry bed reactor proposed in the utility model has many internal components, which may provide a surface for the coking reaction to adhere to, causing serious coking.

[0006] Chinese patent document CN102416307B discloses an internal circulation slurry bed reactor, in which 1 to 160 built-in cylinders are arranged in the reactor cylinder, and the ratio of the height of the built-in cylinder to the height of the reactor cylinder is 0.1 to 1.0, and a gas distributor is arranged at the bottom of each built-in cylinder. The slurry circulates continuously in the reactor, and no external circulation of the slurry is required, and no external circulation pump is required. However, the reactor structure is complex, and there are many internal component structures inside the reactor. Due to the coking reaction in the heavy oil hydrogenation process, the wall surfaces of the internal components may become the coking center, which is not conducive to the stable operation of the device; and the bottom structure of the reactor is complex, and the liquid phase circulation at the bottom of the reactor may be affected, resulting in a flow dead zone, resulting in serious local coking, which is not conducive to the stable operation of the device.

[0007] Chinese patent document CN110339786B discloses a slurry bed liquid feeding method and device for enhancing hydrogenation mass transfer. After the liquid enters the reactor, it first enters a series of parallel vortex components. The liquid outlet of the feeding vortex components forms a rotating jet shape. The liquid in the rotating jet shape has a certain kinetic energy dissipation rate. The gas distribution plate is set in the rotating jet area, and the bubbles are broken and evenly distributed by the rotating jet kinetic energy dissipation. However, the liquid phase feeding method has high liquid phase kinetic energy loss, large pressure drop, and may cause pulse feeding and unstable operation.

[0008] In summary, the internal components of the existing slurry bed reactor are all located inside the slurry bed reactor and have a certain spatial structure, which has a certain influence on the material flow process in the slurry bed reactor, and the internal component structure will become the wall surface for the coke to adhere to, which is not conducive to inhibiting coke formation. Summary of the invention

[0009] In view of this, the present invention provides a heavy oil slurry bed hydrogenation device, comprising a premixing unit, a preheating unit, a feeding unit and a slurry bed hydrogenation reaction unit which are connected in sequence. By arranging a premixing unit for heavy oil and hydrogen, the premixing process of heavy oil and hydrogen is strengthened, the hydrogen content in the heavy oil is increased, and then the generation of coke precursors in the heavy oil during the preheating process is slowed down; by arranging the feeding unit at the bottom of the slurry bed hydrogenation reaction unit, the feeding unit and the slurry bed hydrogenation reaction unit are completely separated, and coking caused by the feeding structure arranged in the slurry bed reactor providing a coke surface or a flow dead zone that may be caused can be avoided; by arranging a gas pipeline and a mixed material pipeline in the feeding unit, and the mixture of heavy oil and hydrogen and hydrogen in the feeding unit are not in contact, the disturbance effect of the hydrogen entering the feeding unit at the bottom of the slurry bed reaction unit is utilized to avoid the deposition of catalysts or coke precursors; at the same time, the liquid phase circulation in the slurry bed reactor is strengthened, the inner wall of the slurry bed reactor is flushed, and the coke formation is further reduced, which is conducive to the stable operation of the device.

[0010] To achieve the above object, the present invention provides the following technical solutions:

[0011] A heavy oil slurry bed hydrogenation device comprises a premixing unit, a preheating unit, a feeding unit and a slurry bed hydrogenation reaction unit which are connected in sequence, and the feeding unit is located at the bottom of the slurry bed hydrogenation reaction unit;

[0012] Wherein, the premixing unit comprises a stirring device (such as a stirring tank, etc.) for strengthening the premixing process of heavy oil and hydrogen;

[0013] The feed unit comprises a gas pipeline and a mixed material pipeline which are not connected or independent of each other, the gas pipeline comprises a second hydrogen inlet and a hydrogen outlet; the mixed material pipeline comprises a first mixed material inlet and at least one second mixed material outlet;

[0014] The slurry bed hydrogenation reaction unit comprises a slurry bed reactor, the interior of the slurry bed reactor is a cavity, and the slurry bed reactor is provided with a product outlet;

[0015] The second mixed material outlet and the hydrogen outlet are respectively connected to the cavity of the slurry bed reactor, that is, the second mixed material outlet and the hydrogen outlet are the corresponding mixed material inlet and hydrogen inlet on the slurry bed reactor.

[0016] Optionally, in the heavy oil slurry bed hydrogenation device provided by the present invention, when there is one second mixed material outlet, the second mixed material outlet is located at the center of the top of the feeding unit.

[0017] Optionally, in the heavy oil slurry bed hydrogenation device provided by the present invention, when the number of the second mixed material outlets is two or more, the second mixed material outlets are evenly distributed at the top of the feed unit.

[0018] Optionally, in the heavy oil slurry bed hydrogenation device provided by the present invention, the hydrogen outlet is composed of evenly distributed small holes, and the diameter of each small hole can be adjusted according to actual conditions and needs. For example, the diameter of each small hole can be set to 1-3 mm.

[0019] Optionally, in the heavy oil slurry bed hydrogenation device provided by the present invention, the feed unit is a cylinder, the cross-sectional area of ​​the cylinder is recorded as A1, the total cross-sectional area of ​​the second mixed material outlet is recorded as A2, the total cross-sectional area of ​​each small hole in the hydrogen outlet is recorded as A3, A3 / (A1-A2)=90%-98%, A2 / A1=30%-80%. Specifically A1, A2 and A3 can be adjusted according to actual needs.

[0020] Optionally, in the heavy oil slurry bed hydrogenation device provided by the present invention, the equipment with stirring is provided with a heavy oil inlet, a first hydrogen inlet and a first mixed material outlet; preferably, the heavy oil inlet and the first hydrogen inlet are respectively located at the bottom of the equipment with stirring and are axially symmetrically distributed.

[0021] Optionally, in the heavy oil slurry bed hydrogenation device provided by the present invention, the first mixture material outlet is located at the upper part of the stirring device; preferably, the first mixture material outlet is located at the top side wall of the stirring device.

[0022] Optionally, in the heavy oil slurry bed hydrogenation device provided by the present invention, the preheating unit comprises an inlet and an outlet, the inlet of the preheating unit is connected to the outlet of the first mixed material; the outlet of the preheating unit is connected to the inlet of the first mixed material.

[0023] During use of the heavy oil slurry bed hydrogenation device provided by the present invention, the pressure of the feed unit is always kept greater than the pressure of the slurry bed hydrogenation reaction unit, ensuring that the material can enter the slurry bed hydrogenation reaction unit and avoiding the backflow of the material in the slurry bed hydrogenation reaction unit. That is, the feed unit always maintains a slightly positive pressure compared to the slurry bed hydrogenation reaction unit.

[0024] The present invention also provides a heavy oil slurry bed hydrogenation method, which uses the above-mentioned heavy oil slurry bed hydrogenation device and comprises the following steps:

[0025] S1: adding the catalyst-containing heavy oil and the first hydrogen into a premixing unit for premixing, and the obtained mixed material enters a preheating unit for preheating;

[0026] S2: the preheated mixed material enters the feed unit through the first mixed material inlet, and then enters the slurry bed hydrogenation reaction unit through the second mixed material outlet; the second hydrogen enters the feed unit through the second hydrogen inlet, and then enters the slurry bed hydrogenation reaction unit through the hydrogen outlet, and the preheated mixed material and the second hydrogen do not contact in the feed unit;

[0027] S3: the preheated mixed material is mixed with the second hydrogen in the slurry bed hydrogenation reaction unit for hydrogenation reaction, and the obtained product is discharged through the product outlet to enter the subsequent process (unreacted hydrogen is discharged together with the product);

[0028] Wherein, in step S1, the premixing temperature is 100-180°C, and the preheating temperature is 280-320°C.

[0029] Optionally, in step S1 of the heavy oil slurry bed hydrogenation method provided by the present invention, the premixing temperature is 120-150°C, and in step S3, the hydrogenation reaction temperature is 380-480°C, preferably 400-450°C.

[0030] Optionally, in step S3 of the heavy oil slurry bed hydrogenation method provided by the present invention, the pressure of the hydrogenation reaction is 8-22 MPa, preferably 14-20 MPa;

[0031] The hydrogen-to-oil ratio of the hydrogenation reaction is 400-2000, preferably 800-1600.

[0032] Optionally, in the heavy oil slurry bed hydrogenation method provided by the present invention, the catalyst in the catalyst-containing heavy oil has a catalyst concentration of 100-1000 ppm based on metal mass.

[0033] Optionally, in the heavy oil slurry bed hydrogenation method provided by the present invention, the volume ratio of the first hydrogen to the second hydrogen is 5:1-1:1, preferably 3:1-1:1.

[0034] Optionally, in the heavy oil slurry bed hydrogenation method provided by the present invention, the heavy oil containing the catalyst and the first hydrogen are added to the premixing unit through the heavy oil inlet and the first hydrogen inlet in the premixing unit respectively for premixing; preferably, the heavy oil with the catalyst is added to the premixing unit along a tangential direction through the heavy oil inlet, and the first hydrogen is added to the premixing unit along a tangential direction through the first hydrogen inlet; more preferably, the addition direction of the heavy oil and the addition direction of the first hydrogen are respectively opposite to the stirring direction in the premixing unit.

[0035] The heavy oil slurry bed hydrogenation device provided by the present invention is provided with a premixing unit, a preheating unit, a feeding unit and a slurry bed hydrogenation reaction unit which are connected in sequence, and the feeding unit is limited to be located at the bottom of the slurry bed hydrogenation reaction unit (that is, the feeding unit and the slurry bed hydrogenation reaction unit are separated into two independent and connected devices); the heavy oil containing the catalyst is first intensively mixed with hydrogen in the premixing unit to increase the hydrogen content in the heavy oil and prevent the aggregation of the catalyst; then it is preheated in the preheating unit, and finally enters the slurry bed hydrogenation reaction unit through the feeding unit, and the hydrogen introduced from the feeding unit is used to disturb the bottom of the slurry bed hydrogenation reaction unit to strengthen the liquid phase circulation in the slurry bed reactor and flush the wall of the slurry bed reactor, and the units cooperate with each other, thereby slowing down the coking in the heavy oil hydrogenation process, which is beneficial to the stable operation of the device. Specifically, compared with the prior art, the present invention has the following advantages:

[0036] Beneficial effect 1: The heavy oil slurry bed hydrogenation device provided by the present invention is provided with a premixing unit, and the heavy oil containing a certain concentration of catalyst and hydrogen are first intensively mixed in the premixing unit. On the one hand, a certain amount of hydrogen can be dissolved in the heavy oil; on the other hand, the catalyst aggregation in the heavy oil can be avoided by stirring, and the catalyst can be well dispersed in the heavy oil. The above effect can well alleviate the formation of a large amount of coke precursors by the heavy oil in the subsequent preheating unit and feeding unit, and further alleviate the coking in the slurry bed hydrogenation reaction process.

[0037] Beneficial effect 2: The heavy oil slurry bed hydrogenation device provided by the present invention can effectively avoid coking due to the feed structure inside the slurry bed reactor providing a coking surface or a flow dead zone that may be caused by providing a completely separated and independent feed unit and slurry bed hydrogenation reaction unit; moreover, part of the raw hydrogen is supplemented by the feed unit, and the feed unit is arranged at the bottom of the slurry bed hydrogenation reaction unit. On the one hand, it can cause a significant disturbance to the flow at the bottom of the slurry bed reactor to avoid the deposition of catalysts or coking materials; on the other hand, it can strengthen the liquid phase circulation in the slurry bed reactor and flush the wall of the slurry bed reactor. The above effects can avoid a large amount of coking and are conducive to the long-term stable operation of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A schematic diagram of a heavy oil slurry bed hydrogenation device provided by the present invention;

[0039] Figure 2 for Figure 1 The schematic diagram of the feed unit and the slurry bed hydrogenation reaction unit in the heavy oil slurry bed hydrogenation unit shown;

[0040] Figure 3 for Figure 2 A left side view of the feed unit shown in ;

[0041] Figure 4 for Figure 2 A top view of the feed unit is shown.

[0042] Figure 5 Schematic diagram of the medium slurry bed hydrogenation reactor used in Comparative Example 1 of the present invention;

[0043] Figure 6 for Figure 5 Schematic diagram of a hydrogen feed distributor in a slurry bed hydrogenation reactor;

[0044] In the figure, 1: stirred tank; 2: preheating unit; 3: feeding unit and slurry bed hydrogenation reaction unit; 4: heavy oil with catalyst; 5-1: first hydrogen; 5-2: second hydrogen; 6: heavy oil hydrogenation product; 3-1: slurry bed reactor; 3-2: feeding unit; 3-4: preheated mixture of heavy oil and hydrogen; 3-2-1: first mixture inlet; 3-2-2: second hydrogen inlet; 3-2-3: second mixture outlet; 3-2-4: hydrogen outlet. DETAILED DESCRIPTION

[0045] The present invention is described in detail below by way of examples. It is necessary to point out that the following examples are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Those skilled in the art in this field can make some non-essential improvements and adjustments to the present invention based on the above content of the present invention.

[0046] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "top", "bottom", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0047] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] In order to better illustrate the technical solution of the present invention, specific embodiments are provided below for illustration, but the following embodiments do not constitute a limitation of the present invention.

[0049] Example 1

[0050] This embodiment provides a heavy oil slurry bed hydrogenation device, comprising a premixing unit, a preheating unit, a feeding unit and a slurry bed hydrogenation reaction unit connected in sequence, and the feeding unit is located at the bottom of the slurry bed hydrogenation reaction unit;

[0051] The premixing unit includes a stirring device for mixing the heavy oil with the hydrogen; the stirring device is not specifically limited, as long as it can mix the heavy oil and the hydrogen by stirring, such as a stirring kettle, etc.;

[0052] The feed unit includes a gas pipeline and a mixed material pipeline that are not connected or independent of each other, the gas pipeline includes a second hydrogen inlet and a hydrogen outlet; the mixed material pipeline includes a first mixed material inlet and at least one second mixed material outlet; the feed unit is not specifically limited, as long as it can accommodate the mixed material pipeline and the gas pipeline to prevent the mixed material and the second hydrogen from mixing in the feed unit;

[0053] The slurry bed hydrogenation reaction unit comprises a slurry bed reactor, wherein the interior of the slurry bed reactor is a cavity, and a product outlet is arranged on the slurry bed reactor; and the slurry bed reactor does not have any built-in components;

[0054] The second mixed material outlet and the hydrogen outlet are respectively connected to the cavity of the slurry bed reactor, that is, the second mixed material outlet and the hydrogen outlet are the corresponding mixed material inlet and the hydrogen inlet on the slurry bed reactor.

[0055] In an optional embodiment, when there is one second mixed material outlet, the second mixed material outlet is located at the center of the top of the feeding unit.

[0056] In another optional embodiment, when there are two or more second mixed material outlets, the second mixed material outlets are evenly distributed on the top of the feeding unit to ensure uniform feeding.

[0057] In an optional embodiment, the hydrogen outlet is composed of evenly distributed small holes, each of which has a diameter of 1-3 mm, which can be adjusted according to actual conditions, such as 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2.0 mm, 2.1 mm, 2.3 mm, 2.5 mm, 2.7 mm, 2.9 mm, etc.

[0058] In an optional embodiment, the feeding unit is a cylinder, the cross-sectional area of ​​the cylinder is recorded as A1, the total cross-sectional area of ​​the second mixed material outlet is recorded as A2, the total cross-sectional area of ​​the small holes in the hydrogen outlet is recorded as A3, A3 / (A1-A2)=90%-98%, such as 91%, 93%, 95%, 97%, etc., which can be adjusted according to actual needs, A2 / A1=30%-80%, such as 32%, 35%, 37%, 39%, 40%, 41%, 43%, 45%, 47%, 49%, 51%, 53%, 55%, 58%, 61%, 63%, 65%, 67%, 69%, 71%, 73%, 75%, 77%, 79%, etc., which can be adjusted according to actual needs.

[0059] In an optional embodiment, the stirring device is provided with a heavy oil inlet, a first hydrogen inlet and a first mixed material outlet; in a preferred embodiment, the heavy oil inlet and the first hydrogen inlet are respectively located at the bottom of the stirring device and are axially symmetrically distributed.

[0060] In an optional embodiment, the first mixed material outlet is located at the upper part of the stirring device; in a preferred embodiment, the first mixed material outlet is located at the top side wall of the stirring device.

[0061] In an optional embodiment, the preheating unit comprises an inlet and an outlet, the inlet of the preheating unit is connected to the outlet of the first mixed material; the outlet of the preheating unit is connected to the inlet of the first mixed material.

[0062] Specifically, when the heavy oil slurry bed hydrogenation device is used for hydrogenation reaction, the heavy oil and hydrogen are first introduced into the premixing unit through the heavy oil inlet and the first hydrogen inlet on the premixing unit, respectively, and premixed under stirring conditions (when the adding direction of the heavy oil and the hydrogen is opposite to the stirring direction, the mixing effect is better), the obtained mixed material is discharged through the first mixed material outlet, and then enters the preheating unit through the inlet of the preheating unit, and is preheated in the preheating unit. The preheated mixed material enters the feeding unit through the outlet of the preheating unit and the first mixed material inlet in turn; at the same time , hydrogen enters the feed unit from the second hydrogen inlet, and the mixed material in the feed unit does not contact the hydrogen entering through the second hydrogen inlet, the mixed material and hydrogen in the feed unit enter the slurry bed hydrogenation reaction unit through the second mixed material outlet and the hydrogen outlet respectively (the disturbance effect of the hydrogen added to the feed unit when entering the slurry bed hydrogenation reaction unit is utilized to strengthen the liquid phase circulation in the slurry bed reactor), and the mixed materials are hydrogenated in the slurry bed hydrogenation reaction unit for hydrogenation reaction, and the obtained hydrogenated product is discharged through the product outlet of the slurry bed hydrogenation reaction unit to enter the subsequent process.

[0063] Example 2

[0064] This embodiment provides a heavy oil slurry bed hydrogenation method, using Figure 1 The device shown, Figure 1 The structure of the medium feed unit and the slurry bed hydrogenation reaction unit is as follows: Figure 2 , Figure 3 and Figure 4 As shown, the following steps are included:

[0065] S1: Add the heavy oil 4 with catalyst and the first hydrogen 5-1 into the stirring tank 1 through the heavy oil inlet and the first hydrogen inlet in a tangential direction respectively (the heavy oil inlet and the first hydrogen inlet are respectively located at the bottom of the stirring tank 1 and are axially symmetrically distributed), and premix them at 120° C. under stirring. The adding direction of the heavy oil 4 with catalyst and the first hydrogen 5-1 is opposite to the stirring direction. The obtained mixed material enters the preheating unit 2 (a heating furnace is used in this embodiment) through the first mixed material outlet located on the top side wall of the stirring tank 1 for preheating;

[0066] S2: The preheated mixture 3-4 of heavy oil and hydrogen enters the feed unit and the slurry bed hydrogenation reaction unit 3. Specifically, the mixture of heavy oil and hydrogen preheated to 320°C enters the feed unit 3-2 through the first mixture inlet 3-2-1, and then directly enters the slurry bed reactor 3-1 through a second mixture outlet 3-2-3; at the same time, the second hydrogen 5-2 enters the feed unit 3-2 through the second hydrogen inlet 3-2-2, and then directly enters the slurry bed reactor 3-1 through the hydrogen outlet 3-2-4 composed of evenly distributed small holes with a diameter of 2.5 mm, and the preheated mixture 3-4 of heavy oil and hydrogen does not contact the second hydrogen 5-2 in the feed unit 3-2;

[0067] S3: The preheated mixture 3-4 of heavy oil and hydrogen and the second hydrogen 5-2 flow from bottom to top in the slurry bed reactor 3-1 and are mixed and hydrogenated at 450°C, 20MPa, and a hydrogen-to-oil ratio of 800. The catalyst concentration in the heavy oil is 100ppm (calculated by the mass of metal in the heavy oil). The obtained heavy oil hydrogenation product 6 is discharged from the product outlet at the top of the slurry bed reactor 3-1 and enters the subsequent process (unreacted hydrogen is discharged together with the product);

[0068] The above-mentioned feeding unit 3-2 is a cylinder, and the cross-sectional area of ​​the cylinder is denoted as A1, the cross-sectional area of ​​the second mixed material outlet is denoted as A2, and the total cross-sectional area of ​​the small holes in the hydrogen outlet is denoted as A3, then A3 / (A1-A2)=90%, A2 / A1=60%.

[0069] The volume ratio of the first hydrogen gas to the second hydrogen gas is 2:1.

[0070] Example 3

[0071] This embodiment provides a heavy oil slurry bed hydrogenation method, using a device similar to that in Example 2 (compared with the device used in Example 2, the only difference is the number of second mixed material outlets in the feed unit. The number of second mixed material outlets in the device used in this embodiment is 3, which are evenly distributed on the top of the feed unit), comprising the following steps:

[0072] S1: adding the heavy oil with catalyst and the first hydrogen into the stirring kettle through the heavy oil inlet and the first hydrogen inlet in a tangential direction respectively, and premixing at 150° C. under stirring, and the adding direction of the heavy oil with catalyst and the first hydrogen is opposite to the stirring direction, and the obtained mixed material enters the preheating unit for preheating;

[0073] S2: The mixture of heavy oil and hydrogen preheated to 280°C enters the feed unit through the first mixture inlet, and then directly enters the slurry bed reactor through the three second mixture outlets; at the same time, the second hydrogen enters the feed unit through the second hydrogen inlet, and then directly enters the slurry bed reactor through the hydrogen outlet composed of evenly distributed small holes with a diameter of 1 mm, and the preheated mixture of heavy oil and hydrogen does not contact the second hydrogen in the feed unit;

[0074] S3: The preheated mixture of heavy oil and hydrogen and the second hydrogen flow from bottom to top in a slurry bed reactor and are mixed and hydrogenated at 400°C, 14 MPa, and a hydrogen-to-oil ratio of 1600. The catalyst concentration in the heavy oil is 1000 ppm (calculated by the mass of metal in the heavy oil). The obtained heavy oil hydrogenation product is discharged from the product outlet at the top of the slurry bed reactor and enters the subsequent process (unreacted hydrogen is discharged together with the product);

[0075] The feed unit is a cylinder, the cross-sectional area of ​​the cylinder is recorded as A1, the cross-sectional area of ​​the second mixed material outlet is recorded as A2, and the total cross-sectional area of ​​the small holes in the hydrogen outlet is recorded as A3, then A3 / (A1-A2)=98% ， A2 / A1=40%.

[0076] The volume ratio of the first hydrogen to the second hydrogen is 3:1.

[0077] Example 4

[0078] This embodiment provides a heavy oil slurry bed hydrogenation method, using the same device as in Example 2, including the following steps:

[0079] S1: adding the heavy oil with catalyst and the first hydrogen into the stirring kettle through the heavy oil inlet and the first hydrogen inlet in a tangential direction respectively, and premixing at 130° C. under stirring, and the adding direction of the heavy oil with catalyst and the first hydrogen is opposite to the stirring direction, and the obtained mixed material enters the preheating unit for preheating;

[0080] S2: The mixture of heavy oil and hydrogen preheated to 300°C enters the feed unit through the first mixture inlet, and then directly enters the slurry bed reactor through a second mixture outlet; at the same time, the second hydrogen enters the feed unit through the second hydrogen inlet, and then directly enters the slurry bed reactor through the hydrogen outlet composed of evenly distributed small holes with a diameter of 1.2 mm, and the preheated mixture of heavy oil and hydrogen does not contact the second hydrogen in the feed unit;

[0081] S3: The preheated mixture of heavy oil and hydrogen and the second hydrogen flow from bottom to top in a slurry bed reactor and are mixed and hydrogenated at 430°C, 16 MPa, and a hydrogen-to-oil ratio of 1200. The catalyst concentration in the heavy oil is 300 ppm (calculated by the mass of metal in the heavy oil). The obtained heavy oil hydrogenation product is discharged from the product outlet at the top of the slurry bed reactor and enters the subsequent process (unreacted hydrogen is discharged together with the product);

[0082] The feed unit is a cylinder, the cross-sectional area of ​​the cylinder is recorded as A1, the cross-sectional area of ​​the second mixed material outlet is recorded as A2, and the total cross-sectional area of ​​the small holes in the hydrogen outlet is recorded as A3, then A3 / (A1-A2)=95% ， A2 / A1=50%.

[0083] The volume ratio of the first hydrogen gas to the second hydrogen gas is 1:1.

[0084] Example 5

[0085] This embodiment provides a heavy oil slurry bed hydrogenation method, using the same device as in Example 2, including the following steps:

[0086] S1: adding the heavy oil with catalyst and the first hydrogen into the stirring tank through the heavy oil inlet and the first hydrogen inlet respectively in a direction perpendicular to the side wall of the stirring tank, premixing at 170° C. under stirring, and the obtained mixed material enters the preheating unit for preheating;

[0087] S2: The mixture of heavy oil and hydrogen preheated to 310°C enters the feed unit through the first mixture inlet, and then directly enters the slurry bed reactor through a second mixture outlet; at the same time, the second hydrogen enters the feed unit through the second hydrogen inlet, and then directly enters the slurry bed reactor through the hydrogen outlet composed of evenly distributed small holes with a diameter of 1.4 mm, and the preheated mixture of heavy oil and hydrogen does not contact the second hydrogen in the feed unit;

[0088] S3: The preheated mixture of heavy oil and hydrogen and the second hydrogen flow from bottom to top in a slurry bed reactor and are mixed and hydrogenated at 380°C, 10 MPa, and a hydrogen-to-oil ratio of 1800. The catalyst concentration in the heavy oil is 600 ppm (calculated by the mass of metal in the heavy oil). The obtained heavy oil hydrogenation product is discharged from the product outlet at the top of the slurry bed reactor and enters the subsequent process (unreacted hydrogen is discharged together with the product);

[0089] The feed unit is a cylinder, the cross-sectional area of ​​the cylinder is recorded as A1, the cross-sectional area of ​​the second mixed material outlet is recorded as A2, and the total cross-sectional area of ​​the small holes in the hydrogen outlet is recorded as A3, then A3 / (A1-A2)=93% ， A2 / A1=75%.

[0090] The volume ratio of the first hydrogen gas to the second hydrogen gas is 5:1.

[0091] Comparative Example 1

[0092] The heavy oil slurry bed hydrogenation method provided in this comparative example is similar to that in Example 2, except that the premixing unit is omitted in the device used, and the heavy oil with catalyst and the first hydrogen are directly mixed in the pipeline before entering the preheating unit. The heavy oil slurry bed hydrogenation method provided in this comparative example specifically includes the following steps:

[0093] S1: The heavy oil with catalyst and the first hydrogen are mixed in the pipeline at 120° C. through a tee, and then enter the preheating unit 2 (a heating furnace is used in this comparative example) for preheating;

[0094] S2: The preheated mixture of heavy oil and hydrogen enters the feed unit and the slurry bed hydrogenation reaction unit. Specifically, the mixture of heavy oil and hydrogen preheated to 320°C enters the feed unit through the first mixture inlet, and then directly enters the slurry bed reactor through a second mixture outlet; at the same time, the second hydrogen enters the feed unit through the second hydrogen inlet, and then directly enters the slurry bed reactor through the hydrogen outlet composed of evenly distributed small holes with a diameter of 2 mm, and the preheated mixture of heavy oil and hydrogen does not contact the second hydrogen in the feed unit;

[0095] S3: The preheated mixture of heavy oil and hydrogen and the second hydrogen flow from bottom to top in a slurry bed reactor and are mixed and hydrogenated at 450°C, 20 MPa, and a hydrogen-to-oil ratio of 800. The catalyst concentration in the heavy oil is 100 ppm (calculated by the mass of metal in the heavy oil). The obtained heavy oil hydrogenation product is discharged from the product outlet at the top of the slurry bed reactor and enters the subsequent process (unreacted hydrogen is discharged together with the product);

[0096] The above-mentioned feeding unit is a cylinder, with the cross-sectional area of ​​the cylinder denoted as A1, the cross-sectional area of ​​the second mixed material outlet denoted as A2, and the total cross-sectional area of ​​the small holes in the hydrogen outlet denoted as A3, then A3 / (A1-A2)=90%, A2 / A1=60%.

[0097] The volume ratio of the first hydrogen gas to the second hydrogen gas is 2:1.

[0098] Comparative Example 2

[0099] This comparative example provides a heavy oil slurry bed hydrogenation method, using a device similar to the device in Example 4, the only difference is that the feed unit and the slurry bed hydrogenation reaction unit are set differently. The feed unit is omitted in this comparative example, and a hydrogen feed distributor is provided at the lower part of the slurry bed hydrogenation reaction unit, such as Figure 5 and Figure 6 As shown, the specific steps include:

[0100] S1: Add the heavy oil 4 with catalyst and the first hydrogen 5-1 into the stirring kettle 1 through the heavy oil inlet and the first hydrogen inlet in a tangential direction respectively, and premix them at 130° C. under stirring, and the adding direction of the heavy oil 4 with catalyst and the first hydrogen 5-1 is opposite to the stirring direction, and the obtained mixed material enters the preheating unit 2 for preheating;

[0101] S2: The mixture 3-4 of heavy oil and hydrogen preheated to 300°C directly enters the slurry bed reactor through the bottom of the slurry bed reactor; at the same time, the second hydrogen 5-2 enters the hydrogen feed distributor through the second hydrogen inlet 3-2-2, and directly enters the slurry bed reactor through the hydrogen outlet 3-2-4 composed of evenly distributed small holes with a diameter of 3 mm;

[0102] S3: The preheated mixture of heavy oil and hydrogen and the second hydrogen flow from bottom to top in a slurry bed reactor and are mixed and hydrogenated at 430°C, 16 MPa, and a hydrogen-to-oil ratio of 1200. The catalyst concentration in the heavy oil is 300 ppm (calculated by the mass of metal in the heavy oil). The obtained heavy oil hydrogenation product is discharged from the product outlet at the top of the slurry bed reactor and enters the subsequent process (unreacted hydrogen is discharged together with the product);

[0103] The volume ratio of the first hydrogen gas to the second hydrogen gas is 1:1.

[0104] The coking rate of the heavy oil slurry bed hydrogenation method in the above-mentioned embodiments and comparative examples after running for 500 hours is shown in the following table.

[0105] Table 1

[0106] Coke production rate after 500h operation % Example 2 0.73 Example 3 0.54 Example 4 0.67 Example 5 0.92 Comparative Example 1 1.64 Comparative Example 2 1.32

[0107] It can be seen from the data in the above table that the heavy oil slurry bed hydrogenation method provided by the present invention adopts a premixing unit, a preheating unit, a feeding unit and a slurry bed hydrogenation reaction unit comprising a stirring device connected in sequence, and the gas and the material in the feeding unit are not in contact, so that the enhanced mixing and hydrogen dissolution process of the heavy oil containing the catalyst and the hydrogen before preheating can significantly slow down the coking during the heavy oil hydrogenation process; moreover, no components are arranged in the slurry bed reactor, which also significantly slows down the generation of coke in the slurry bed reactor.

[0108] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, technicians familiar with the field may make various corresponding changes and deformations based on the present invention, but these corresponding changes and deformations should all fall within the scope of protection of the claims of the present invention.

Claims

1. A heavy oil slurry bed hydrogenation device, characterized in that: It comprises a premixing unit, a preheating unit, a feeding unit and a slurry bed hydrogenation reaction unit which are connected in sequence, and the feeding unit is located at the bottom of the slurry bed hydrogenation reaction unit; Wherein, the premixing unit comprises a device with stirring; The feed unit comprises a gas pipeline and a mixed material pipeline which are not connected or independent of each other, the gas pipeline comprises a second hydrogen inlet and a hydrogen outlet; the mixed material pipeline comprises a first mixed material inlet and at least one second mixed material outlet; The slurry bed hydrogenation reaction unit comprises a slurry bed reactor, the interior of the slurry bed reactor is a cavity, and the slurry bed reactor is provided with a product outlet; The second mixed material outlet and the hydrogen outlet are respectively communicated with the cavity of the slurry bed reactor.

2. The heavy oil slurry bed hydrogenation device according to claim 1, characterized in that: When there is one second mixed material outlet, the second mixed material outlet is located at the center of the top of the feeding unit.

3. The heavy oil slurry bed hydrogenation device according to claim 1, characterized in that: When there are two or more second mixed material outlets, the second mixed material outlets are evenly distributed on the top of the feeding unit.

4. The heavy oil slurry bed hydrogenation device according to claim 1, characterized in that: The hydrogen outlet is composed of evenly distributed small holes, and the diameter of each small hole is 1-3 mm.

5. The heavy oil slurry bed hydrogenation device according to claim 4, characterized in that: The feeding unit is a cylinder, the cross-sectional area of ​​the cylinder is denoted as A1, the total cross-sectional area of ​​the second mixed material outlet is denoted as A2, the total cross-sectional area of ​​the small holes in the hydrogen outlet is denoted as A3, A3 / (A1-A2)=90%-98%, A2 / A1=30%-80%.

6. The heavy oil slurry bed hydrogenation device according to claim 1, characterized in that: The stirring device is provided with a heavy oil inlet, a first hydrogen inlet and a first mixed material outlet; preferably, the heavy oil inlet and the first hydrogen inlet are respectively located at the bottom of the stirring device and are axially symmetrically distributed.

7. The heavy oil slurry bed hydrogenation device according to claim 5, characterized in that: The first mixed material outlet is located at the upper part of the stirring device; preferably, the first mixed material outlet is located at the top side wall of the stirring device.

8. A heavy oil slurry bed hydrogenation method, characterized in that: The heavy oil slurry bed hydrogenation device according to any one of claims 1 to 7 comprises the following steps: S1: adding the catalyst-containing heavy oil and the first hydrogen into a premixing unit for premixing, and the obtained mixed material enters a preheating unit for preheating; S2: the preheated mixed material enters the feed unit through the first mixed material inlet, and then enters the slurry bed hydrogenation reaction unit through the second mixed material outlet; After the second hydrogen enters the feed unit through the second hydrogen inlet, it enters the slurry bed hydrogenation reaction unit through the hydrogen outlet, and the preheated mixed material does not contact the second hydrogen in the feed unit; S3: the preheated mixed material is mixed with the second hydrogen in the slurry bed hydrogenation reaction unit for hydrogenation reaction, and the obtained product is discharged through the product outlet; Wherein, in step S1, the premixing temperature is 100-180°C, and the preheating temperature is 280-320°C.

9. The heavy oil slurry bed hydrogenation method according to claim 8, characterized in that: In step S1, the premixing temperature is 120-150°C; in step S3, the hydrogenation reaction temperature is 380-480°C, preferably 400-450°C.

10. The heavy oil slurry bed hydrogenation method according to claim 8, characterized in that: In step S3, the pressure of the hydrogenation reaction is 8-22 MPa, preferably 14-20 MPa; the hydrogen-to-oil ratio of the hydrogenation reaction is 400-2000, preferably 800-1600.

11. The heavy oil slurry bed hydrogenation method according to claim 8, characterized in that: In the catalyst-containing heavy oil, the catalyst concentration in the catalyst-containing heavy oil is 100-1000 ppm based on the metal mass of the catalyst.

12. The heavy oil slurry bed hydrogenation method according to claim 8, characterized in that: The volume ratio of the first hydrogen gas to the second hydrogen gas is 5:1-1:1, preferably 3:1-1:

1.

13. The heavy oil slurry bed hydrogenation method according to claim 8, characterized in that: The catalyst-containing heavy oil and the first hydrogen are added to the premixing unit through the heavy oil inlet and the first hydrogen inlet in the premixing unit respectively for premixing; preferably, the catalyst-containing heavy oil is added to the premixing unit along a tangential direction through the heavy oil inlet, and the first hydrogen is added to the premixing unit along a tangential direction through the first hydrogen inlet; more preferably, the adding directions of the heavy oil and the first hydrogen are respectively opposite to the stirring direction in the premixing unit.

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