A liquid phase selective hydrogenation device for petroleum products and a stacked reactor

Abstract

The present invention discloses a liquid phase selective hydrogenation device for petroleum products, which relates to the technical field of hydrofining of petroleum hydrocarbon products, and solves the technical problems of large reaction depth and large aromatic loss in the hydrodeolefination reaction in the related technology. The device includes a micro-channel hydrogen dissolving mechanism, a central tube and a catalyst bed. The micro-channel hydrogen dissolving mechanism is connected with a raw material inlet and a hydrogen inlet. A plurality of hydrogen-mixed oil holes are arranged at intervals along the circumference and axially at intervals on the peripheral wall of the central tube. One axial end of the central tube is connected to the micro-channel hydrogen dissolving mechanism. The raw material inlet and the hydrogen inlet are arranged at intervals from the central tube. The catalyst bed is arranged outside the peripheral wall of the central tube, and the hydrogen-mixed oil holes are connected to the catalyst bed. The hydrogen-mixed oil specifically enters the catalyst bed along the radial direction of the central tube to carry out the hydrogenation deolefination reaction. The flow in the radial direction is conducive to the balanced distribution of the fluid, without a reaction dead zone, and the hydrogen is fully in contact with the reforming product oil.

Description

Technical Field

[0001] The invention relates to the technical field of hydrogenation refining of petroleum hydrocarbon products, and in particular to a liquid phase selective hydrogenation device for petroleum products and a stacked reactor. Background Art

[0002] Catalytic reforming is a key technology in the oil refining industry chain. With the commissioning of large-scale continuous reforming aromatics units, the depth of reaction has increased, and the olefin content in the reformed oil has increased. In a high-severity continuous catalytic reforming unit, the olefin content of the generated oil can reach up to 2.0wt%. Trace olefin impurities in the reformed oil are very likely to undergo polymerization to form colloids, which will not only affect the bromine index and acid wash colorimetry of the aromatic products, but also polymerize in the aromatic extraction solvent to contaminate the extraction solvent and cause corrosion to the extraction system equipment. In addition, olefins are also poisons for downstream disproportionation and isomerization reaction catalysts and adsorbents for adsorption separation units, which will affect their selectivity and accelerate their deactivation rate.

[0003] The conventional method for removing olefins in continuous reforming units is clay / molecular sieve adsorption refining, but the refining depth is not high and the product quality is unstable. In particular, clay is easily deactivated, difficult to regenerate, and needs to be replaced frequently to meet product quality requirements. If waste clay is not properly disposed of, it will also cause serious environmental pollution, which puts companies under tremendous environmental pressure and is gradually being replaced by hydrogenation deolefination solutions.

[0004] In the hydrodeolefination technology, the traditional fixed bed reactor is used, but the hydrogenation depth is difficult to fully cover the wide-fraction aromatic products, the operating conditions are relatively harsh, the reaction depth is large, the selectivity of the catalyst is reduced, and some aromatics will be saturated by hydrogenation. It is difficult to simultaneously meet the requirements of the bromine index of the hydroreforming oil being less than 100mgBr / 100g and the aromatic loss being less than 0.5w%, and a kaolin tank is required for deep treatment. In addition, the hydrogenation reaction pressure is relatively high, and the equipment investment cost is also high. Summary of the invention

[0005] The present application provides a liquid phase selective hydrogenation device for petroleum products and a stacked reactor, which solve the technical problems of high reaction depth and large aromatic loss in the hydrogenation deolefination reaction in the related art.

[0006] The present application provides a liquid phase selective hydrogenation device for petroleum products, the device comprising a micro-channel hydrogen dissolving mechanism, a central tube and a catalyst bed, the micro-channel hydrogen dissolving mechanism being conductively connected with a raw material inlet and a hydrogen inlet, a peripheral wall of the central tube being provided with a plurality of hydrogen-overmixed oil holes which are distributed at intervals in the circumferential direction and at intervals in the axial direction, one axial end of the central tube being connected with the micro-channel hydrogen dissolving mechanism, the raw material inlet and the hydrogen inlet being both arranged at intervals from the central tube, the catalyst bed being arranged outside the peripheral wall of the central tube, and the hydrogen-overmixed oil holes being conductively connected to the catalyst bed.

[0007] Optionally, the device further comprises:

[0008] An outer net is arranged outside the central tube and is enclosed with the peripheral wall of the central tube to form a first chamber, and the catalyst bed is accommodated in the first chamber; and

[0009] The outer shell is arranged outside the outer net and encloses the outer net to form a second chamber. The outer shell is also provided with a reaction product outlet which is communicated with the second chamber.

[0010] Optionally, the device further comprises:

[0011] The filter is arranged between the catalyst bed and the peripheral wall of the central tube.

[0012] Optionally, the microchannel hydrogen dissolving mechanism is arranged at the bottom of the shell, and the reaction product outlet is opened at the top of the shell.

[0013] Optionally, the device further comprises:

[0014] The inert support body is arranged inside the outer shell and at the bottom side of the catalyst bed.

[0015] Optionally, the hydrogenation reaction temperature of the device is controlled to be 80 to 200°C.

[0016] Optionally, the hydrogenation reaction pressure of the device is controlled to be 1.2 to 2.0 MPa.

[0017] Optionally, the hydrogenation reaction volume space velocity of the device is controlled to be 4.0 to 20.0 hr -1 .

[0018] Optionally, the volume ratio of hydrogen to raw material in the device is controlled to be 2 to 10.

[0019] A stacked reactor comprises the above-mentioned device. The stacked reactor comprises at least two devices arranged in sequence, and the reaction product outlet of one of the two adjacent devices is connected to the raw material inlet of the other device.

[0020] The beneficial effects of the present application are as follows: the present application provides a liquid phase selective hydrogenation device for petroleum products, wherein raw materials and hydrogen are input into a micro-channel hydrogen dissolving mechanism, and the hydrogen can be dispersed into micro-bubbles through the micro-channel hydrogen dissolving mechanism to form a fully dissolved mixed hydrogen oil, and the micro-channel hydrogen dissolving mechanism is conducive to increasing the mass transfer area, increasing the residence time, and shortening the contact time with the catalyst, greatly reducing the saturation reaction of aromatics, and significantly reducing the loss of aromatics; the mixed hydrogen oil enters the catalyst bed from the hydrogen-mixed oil holes on the peripheral wall of the central tube, specifically enters the catalyst bed along the radial direction of the central tube, and performs a hydrogenation and deolefination reaction, and the flow in the radial direction is conducive to balanced fluid distribution, and there is no reaction dead zone, and hydrogen and The reforming product oil is fully in contact, the catalyst bed temperature is evenly distributed, there is no hot spot, the bed pressure drop is small, the reaction efficiency is high, and the catalyst service life is long; the device has no hydrogen circulation system and liquid phase circulation system, the process is simple, the required reaction hydrogen partial pressure is low, the operating pressure can be significantly reduced, and the equipment investment and operating costs are reduced; the catalyst suitable for this device has a wide selection; compared with the traditional axial fixed bed reactor, the device is conducive to increasing the reaction space velocity, reducing the reaction pressure, reducing the bed pressure drop, reducing energy consumption, reducing equipment investment, and the obtained reforming product oil guarantees that the bromine index can be below 20mgBr / 100g, and the loss of aromatics is small. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention.

[0022] Figure 1 A schematic diagram of the structure of a liquid phase selective hydrogenation device for petroleum products provided in Example 1;

[0023] Figure 2 This is a schematic diagram of the structure of a stacked reactor provided in Example 2.

[0024] The attached drawings are marked with: 1-central tube, 2-external net, 3-catalyst bed, 4-micro-channel hydrogen dissolving mechanism, 5-reaction medium flow direction, 6-inert support, A-raw material inlet, B-hydrogen inlet, C-reaction product outlet, D-hydrogen supplementary feed port. DETAILED DESCRIPTION

[0025] The embodiments of the present application provide a liquid phase selective hydrogenation device for petroleum products and a stacked reactor, thereby solving the technical problems of high reaction depth and large aromatic loss in the hydrogenation deolefination reaction in the related art.

[0026] The technical solution in the embodiment of the present application is to solve the above technical problems, and the overall idea is as follows:

[0027] A liquid phase selective hydrogenation device for petroleum products comprises a micro-channel hydrogen dissolving mechanism, a central tube and a catalyst bed. The micro-channel hydrogen dissolving mechanism is connected with a raw material inlet and a hydrogen inlet. A plurality of hydrogen-mixed oil holes which are distributed at intervals in the circumferential direction and at intervals in the axial direction are provided on the peripheral wall of the central tube. One axial end of the central tube is connected with the micro-channel hydrogen dissolving mechanism. Both the raw material inlet and the hydrogen inlet are arranged at intervals from the central tube. The catalyst bed is arranged outside the peripheral wall of the central tube, and the hydrogen-mixed oil holes are connected to the catalyst bed.

[0028] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0029] Example 1

[0030] Please refer to Figure 1 The present embodiment discloses a liquid phase selective hydrogenation device for petroleum products, the device comprises a micro-channel hydrogen dissolving mechanism 4, a central tube 1 and a catalyst bed 3, the micro-channel hydrogen dissolving mechanism 4 is conductively connected with a raw material inlet A and a hydrogen inlet B, a peripheral wall of the central tube 1 is provided with a plurality of hydrogen-mixed oil holes which are distributed at intervals in the circumferential direction and at intervals in the axial direction, one axial end of the central tube 1 is connected with the micro-channel hydrogen dissolving mechanism 4, the raw material inlet A and the hydrogen inlet B are both arranged at intervals from the central tube 1, the catalyst bed 3 is arranged outside the peripheral wall of the central tube 1, and the hydrogen-mixed oil holes are conductively connected to the catalyst bed 3.

[0031] The inventors have found that the reactor type and hydrogen dissolution facility used in the liquid-phase hydrogenation deolefination process of the reformed oil have completely different effects on the operating conditions and the hydrogenation effect achieved; the reformed oil hydrogenation reactor of the related art adopts a traditional fixed-bed axial reactor, which has problems such as uneven distribution of the reaction materials in the catalyst bed 3 and poor gas-liquid mass transfer between hydrogen and the reformed oil. It is difficult to process raw materials with high olefin content, and the aromatics loss of the reformed oil after hydrogenation treatment is large. The olefins cannot meet the quality requirements of downstream aromatic products, and white clay needs to be set for further treatment.

[0032] Therefore, the inventor invented a petroleum product liquid phase selective hydrogenation device, such as Figure 1 As shown, Figure 1 The reaction medium flow direction 5 is shown. Specifically, the raw material and hydrogen are input into the micro-channel hydrogen dissolving mechanism 4. The hydrogen can be dispersed into micro bubbles through the micro-channel hydrogen dissolving mechanism 4 to form a fully dissolved hydrogen mixed oil. The hydrogen mixed oil flows into the central tube 1. The hydrogen mixed oil enters the catalyst bed 3 from the hydrogen mixed oil holes on the peripheral wall of the central tube 1, and specifically enters the catalyst bed 3 along the radial direction of the central tube 1 to perform a hydrogenation and deolefination reaction. The reaction products pass through the catalyst bed 3 to be collected and flowed out. The entire reaction is a liquid phase reaction.

[0033] Among them, the micro-channel hydrogen dissolving mechanism 4 can optionally adopt a micron-level porous plate structure to disperse the hydrogen into micro bubbles with a diameter of 100-300 microns; the micro-channel hydrogen dissolving mechanism 4 can also adopt other schemes, such as a hydrogen dissolving pipeline is provided, the raw material is passed into one end of the hydrogen dissolving pipeline, and a plurality of vents are evenly arranged on the wall of the hydrogen dissolving pipeline for hydrogen to flow through.

[0034] In this device, the raw material enters the micro-channel hydrogen dissolving mechanism 4 through the raw material inlet A, and the hydrogen enters the micro-channel hydrogen dissolving mechanism 4 through the hydrogen inlet B. The raw material may be reforming oil from a reforming device, or other petroleum products.

[0035] In the device, the micro-porous hydrogen dissolving mechanism 4 is beneficial to increase the mass transfer area, increase the residence time, shorten the contact time with the catalyst, greatly reduce the aromatic saturation reaction, and significantly reduce the aromatic loss.

[0036] In the device, the mixed hydrogen oil enters the catalyst bed 3 radially along the central tube 1. The flow in the radial direction is conducive to balanced fluid distribution, no reaction dead zone, full contact between hydrogen and reforming oil, uniform temperature distribution of the catalyst bed 3, no hot spots, small bed pressure drop, high reaction efficiency and long catalyst service life.

[0037] In the device, there is no hydrogen circulation system and liquid phase circulation system, the process is simple, and the required reaction hydrogen partial pressure is low, which can significantly reduce the operating pressure, reduce equipment investment and operating costs; the catalysts suitable for this device are widely selected.

[0038] Compared with the traditional axial fixed bed reactor, the device is conducive to increasing the reaction space velocity, reducing the reaction pressure, reducing the bed pressure drop, reducing energy consumption, and reducing equipment investment. The bromine index of the reformed oil obtained can be guaranteed to be below 20 mgBr / 100g, and the loss of aromatics is small, which may not exceed 0.1wt%.

[0039] Alternatively, if Figure 1 As shown, the device also includes an outer net 2 and an outer shell. The outer net 2 is arranged outside the central tube 1, and the outer net 2 and the peripheral wall of the central tube 1 form a first chamber, and the catalyst bed 3 is accommodated in the first chamber; the outer shell is arranged outside the outer net 2, and the outer shell and the outer net 2 form a second chamber. The outer shell also has a reaction product outlet C, and the reaction product outlet C is connected to the second chamber.

[0040] The outer net 2 can be a cylindrical net, a fan-shaped cylinder, etc. In the present device, the reaction product passes through the catalyst bed 3 and flows into the outer annular space of the outer net 2, that is, flows into the second chamber, and is collected and flows out from the reaction product outlet C. Optionally, the reaction product outlet C is opened at the top of the shell.

[0041] Optionally, the device further includes a filter screen, which is arranged between the catalyst bed 3 and the peripheral wall of the central tube 1. In this solution, the diameter of the hydrogen-mixed oil hole is limited by the size of the catalyst particles and the peripheral wall of the central tube 1, so a filter screen is added, specifically: the filter hole of the filter screen is smaller than the size of the catalyst particles, and the hydrogen-mixed oil hole is larger than the size of the catalyst particles. Optionally, the filter screen is a Johnson screen.

[0042] Alternatively, if Figure 1 As shown, the micro-channel hydrogen dissolving mechanism 4 is arranged at the bottom of the shell, and the reaction product outlet C is opened at the top of the shell, so that when the mixed hydrogen oil flows into the central tube 1, it is realized from bottom to top, which is conducive to fully entering the catalyst bed 3 through the multiple distributed mixed hydrogen oil holes along the peripheral wall of the central tube 1.

[0043] Optionally, the plurality of hydrogen-mixed oil holes are evenly distributed on the peripheral wall of the central tube 1 , including a plurality of hydrogen-mixed oil holes distributed along the circumference of the central tube 1 and a plurality of hydrogen-mixed oil holes distributed along the axial direction of the central tube 1 .

[0044] Alternatively, if Figure 1 As shown, the device further includes an inert support 6, which is disposed inside the housing and disposed at the bottom side of the catalyst bed 3. Lifting the catalyst bed 3 by the inert support 6 is conducive to fully utilizing the catalyst and avoiding waste of catalyst by setting up extra catalyst storage space, especially when the catalyst is of high value.

[0045] Optionally, the device is suitable for reforming oil with an aromatic content of 60 to 95 wt% and a bromine value of 1000 to 7000 mgBr / 100 g oil.

[0046] Optionally, the hydrogenation reaction temperature of the device is controlled to be 80 to 200°C, preferably 100 to 150°C.

[0047] Optionally, the hydrogenation reaction pressure of the device is controlled to be 1.2 to 2.0 MPa, preferably 1.2 to 1.6 MPa.

[0048] Optionally, the hydrogenation reaction volume space velocity of the device is controlled to be 4.0 to 20.0 hr-1, preferably 6.0 to 10.0 hr-1.

[0049] Optionally, the volume ratio of hydrogen to raw material in the device is controlled to be 2 to 10, preferably 2 to 5.

[0050] Accordingly, the operating conditions of the device are mild, the reaction pressure is low, only 1.2 to 1.6 MPa, and the reaction temperature is only 100 to 150°C; the reaction space velocity is high, the reactor size is small, the catalyst dosage is small, and investment is saved.

[0051] Example 2

[0052] like Figure 2 As shown, combined Figure 1 This embodiment discloses a stacked reactor, including the petroleum product liquid phase selective hydrogenation device of embodiment 1. Specifically, the stacked reactor includes at least two petroleum product liquid phase selective hydrogenation devices arranged in sequence, and the reaction product outlet C of one of the two adjacent devices is connected to the raw material inlet A of the other device. The hydrogen inlet B of the other device can be used as Figure 2 The hydrogen supplement feed port D is used to supplement the hydrogen consumed in the reaction and improve the reaction depth.

[0053] The stacked reactor of this embodiment can also be composed of 3, 4, etc. petroleum product liquid phase selective hydrogenation units, and is used to process high-olefin reforming oil.

[0054] The stacked reactor of this embodiment can reduce the floor space and save equipment investment; a micro-channel hydrogen dissolving mechanism 4 is provided at the bottom of each reactor stage, and a hydrogen supplement line is provided to ensure the depth of olefin hydrogenation.

[0055] Example 3

[0056] Using Example 1 Figure 1 The petroleum product liquid phase selective hydrogenation unit shown in the figure uses reformed oil produced by a continuous reforming unit in a refinery as raw material, with a flow rate of 60714 kg / h, an aromatic content of 72.6 wt%, and a bromine index of 1980 mgBr / 100 g. The catalyst is a commercially available FDO-18 hydrogenation catalyst, and the reaction operating conditions and products are shown in Table 1 below.

[0057] Table 1

[0058] Reaction temperature, °C 120 Reaction pressure, MPa 1.2 Volume space velocity, h-1 8 Hydrogen to oil volume ratio 2 Bromine index, mgBr / 100g 17 Aromatic loss, wt% 0.05

[0059] Example 4

[0060] The reactor, raw materials and catalyst are the same as those in Example 3, but the reaction pressure is increased. The reaction operating conditions and products are shown in Table 2 below.

[0061] Table 2

[0062] Reaction temperature, °C 120 Reaction pressure, MPa 1.6 Volume space velocity, h-1 8 Hydrogen to oil volume ratio 2 Bromine index, mgBr / 100g 10 Aromatic loss, wt% 0.08

[0063] Example 5

[0064] Using Example 2 Figure 2 The stacked reactor shown in the figure uses reforming oil produced by a continuous reforming unit in a refinery as the raw material, with a flow rate of 69100 kg / h, an aromatic content of 85.2 wt%, and a bromine index of 5220 mgBr / 100 g. The catalyst is a commercially available FDO-18 hydrogenation catalyst, and the reaction operating conditions and products are shown in Table 3 below.

[0065] Table 3

[0066] Reaction temperature, °C 140 Reaction pressure, MPa 1.6 Volume space velocity, h-1 8 Total hydrogen to oil volume ratio 3 (including hydrogen replenishment between reactors) Bromine index, mgBr / 100g 8 Aromatic loss, wt% 0.1

[0067] Example 6

[0068] The reactor, raw materials and catalyst are the same as those in Example 5. The feed rate is 100% load, i.e. 101100 kg / h. The operating conditions are changed. The reaction operating conditions and products are shown in Table 4 below.

[0069] Table 4

[0070] Reaction temperature, °C 150 Reaction pressure, MPa 1.8 Volume space velocity, h-1 12 Total hydrogen to oil volume ratio 4 (including hydrogen replenishment between reactors) Bromine index, mgBr / 100g 20 Aromatic loss, wt% 0.09

[0071] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0072] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A liquid phase selective hydrogenation device for petroleum products, characterized in that: The device comprises: A micro-channel hydrogen dissolving mechanism, wherein the micro-channel hydrogen dissolving mechanism is conductively connected to a raw material inlet and a hydrogen inlet; A central tube, wherein a plurality of hydrogen-mixed oil holes are arranged at intervals in the circumferential direction and in the axial direction on the peripheral wall of the central tube, an axial end of the central tube is connected to the micro-channel hydrogen dissolving mechanism, and the raw material inlet and the hydrogen inlet are arranged at intervals from the central tube; and A catalyst bed is arranged outside the peripheral wall of the central tube, and the supermixed hydrogen oil hole is connected to the catalyst bed; The hydrogenation reaction temperature of the device is controlled to be 80 to 200°C, the hydrogenation reaction pressure of the device is controlled to be 1.2 to 2.0 MPa, and the hydrogenation reaction volume space velocity of the device is controlled to be 4.0 to 20.0 hr -1 The volume ratio of hydrogen to raw material in the device is controlled to be 2 to 10, so as to obtain a reaction product with a bromine index of less than 20 mgBr / 100 g and an aromatic hydrocarbon loss of no more than 0.1 wt%.

2. The device according to claim 1, characterized in that The device also includes: an outer net, arranged outside the central tube, and enclosing with the peripheral wall of the central tube to form a first chamber, wherein the catalyst bed is accommodated in the first chamber; and The outer shell is arranged outside the outer net and encloses the outer net to form a second chamber. The outer shell is also provided with a reaction product outlet, and the reaction product outlet is communicated with the second chamber.

3. The device according to claim 2, characterized in that The device also includes: The filter screen is arranged between the catalyst bed and the peripheral wall of the central tube.

4. The device according to claim 2, characterized in that The microchannel hydrogen dissolving mechanism is arranged at the bottom of the shell, and the reaction product outlet is opened at the top of the shell.

5. The device according to claim 4, characterized in that The device also includes: An inert support body is arranged inside the shell and at the bottom side of the catalyst bed.

6. A stacked reactor, characterized in that: The device comprises any one of claims 2 to 5, wherein the stacked reactor comprises at least two devices arranged in sequence, and the reaction product outlet of one of the two adjacent devices is connected to the raw material inlet of the other device.

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