Hydrogenation olefin removal device and process for reformate

Abstract

The invention discloses a hydrogenation olefin removal device and process for reformate. The device comprises a divided-wall rectifying tower and a hydrogenation reactor, wherein the hydrogenation reactor sequentially comprises a reaction zone I, an upper hydrogen mixing zone, a separation zone, a lower hydrogen mixing zone and a reaction zone II from top to bottom; the process comprises the following steps: separating raw materials through a divided-wall rectifying tower to obtain C7 and below light components, a side line C8 component and a tower bottom C9 + heavy component; wherein C7 and below light components and C8 components are mixed with hydrogen and enter a reaction zone I for a hydrogenation deolefination reaction, and light component products flow out from the top of the hydrogenation reactor; and the tower bottom C9 + heavy component and the residual component are mixed with hydrogen and then enter a reaction zone II for hydrogenation olefin removal reaction, and a heavy component product flows out from the bottom of the hydrogenation reactor and is mixed with a light component product flowing out from the top to obtain a whole-fraction refined product. According to the invention, the olefin content in the reformate is effectively reduced, and the aromatic hydrocarbon saturation degree is reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of oil refining and chemical industry, and particularly relates to a reforming product oil hydrogenation deolefinization device and process. BACKGROUND

[0002] The reforming product oil is a main product of catalytic reforming process technology, and is a light distillate oil rich in aromatic hydrocarbons. Catalytic reforming / aromatic extraction is a main process for producing benzene, toluene, xylene (BTX) and C9+ aromatic hydrocarbons and other chemical raw materials. The reforming product oil selective hydrogenation deolefinization technology has benzene fraction, BTX fraction and full fraction. Due to the harsh reaction conditions of the catalytic reforming process, a certain amount of olefins is contained in the reforming product oil, especially the selective hydrogenation deolefinization of the full fraction is most difficult. The raw material is relatively complex, the hydrogenation treatment load is increased, and higher requirements are put forward for the catalyst and the treatment method. At the same time, the aromatic hydrocarbon content in the full fraction reforming product oil is between 50m% and 70m%, in order to improve the efficiency of the device, the loss of aromatic hydrocarbons is reduced while the olefins are saturated, and the treatment method is also required.

[0003] In view of the problem of olefins in the reforming product oil, in the early stage, China mainly adopts the clay refining process technology, which adsorbs olefins and causes polymerization and alkylation reaction through physical adsorption / chemical reaction. However, the clay refining technology has large loading capacity, fast deactivation speed, and after deactivation, it is a dangerous solid waste, which has high treatment cost and pollutes the environment. Combined with the market demand for deolefinization of catalytic reforming product oil, FRIPP (Sinopec (Dalian) Petroleum Chemical Research Institute Co., Ltd.) developed the FHDO reforming product oil liquid selective deolefinization process technology. HDO-18 noble metal catalyst is adopted, a small amount of new hydrogen is supplemented for the reaction through the hydrogen oil mixing mode under the condition that the main process is unchanged, the olefins in the full fraction of the reforming product oil can be flexibly and efficiently removed, the olefin removal under mild conditions is realized, and the aromatic hydrocarbon components are retained, so as to meet the requirements of the downstream device for the content of olefins.

[0004] In the existing reforming product oil selective hydrogenation deolefinization technology, the deolefinization catalyst is divided into noble metal catalyst and non-noble metal catalyst. The Pt-Pd catalyst is mostly used in the noble metal catalyst, and the deolefinization reaction is carried out under relatively mild reaction conditions of low temperature and low pressure. The initial activity of the catalyst is relatively high, but since the Pt-Pd is expensive, the loading capacity and the number of surface active sites are limited, which leads to the deactivation of the catalyst after carbon deposition.

[0005] As for the non-noble metal catalyst, Mo-Co or Mo-Ni in sulfided state is usually used as the active component, and the deolefinization reaction is carried out under high temperature (250℃-320℃) and low space velocity (1h -1 ~2h -1The deolefin reaction is carried out under the condition that the catalyst has a relatively high initial activity, but in the hydrogenation of the olefins in the reforming oil generated in the reactor, a certain degree of exothermic reaction occurs, which leads to the saturation of the deep olefins and the partial saturation of the aromatic hydrocarbons, thereby causing the loss of the aromatic hydrocarbons.

[0006] For the existing deolefin reaction system of the reforming oil, one hydrogenation reactor is usually provided and the full-range feedstock is once passed through the reactor. In the case that the catalyst has a relatively high initial activity and the hydrogenation of the olefins generates heat, a certain degree of loss of the aromatic hydrocarbons is caused, and the performance of the catalyst is limited. At the same time, the single reactor cannot be adjusted for the reaction of the olefins in each fraction, the reaction severity is set to be high, the efficiency of the removal of the olefins is limited, and the operation cycle of the device is shortened.

[0007] CN102911721A discloses a method for the selective hydrogenation deolefin of the reforming oil in liquid phase circulation. The method mixes part of the liquid products after the hydrogenation reaction with the fresh feedstock, and the mixed products are segmented into the hydrogenation reactor to realize the partial circulation of the liquid products, so as to improve the effect of the removal of the olefins in the products. However, the process flow of the method needs to be provided with a circulating pump, which increases the construction investment and energy consumption of the device and the loss of the aromatic hydrocarbons at the initial stage of the reaction is not obviously improved.

[0008] CN106311093A discloses a reactor for the hydrogenation deolefin of the reforming oil. The reactor is provided with a feedstock distribution zone, a reaction zone and a product collection zone for the deolefin reaction. The distribution device is arranged to improve the contact degree of the feedstock and hydrogen and increase the gas-liquid mass transfer effect. At the same time, the liquid seal effect of the product collection zone ensures that the reaction hydrogen stays in the reaction zone, and the hydrogen circulation equipment is omitted. Although the hydrogen utilization rate is improved, the single reaction condition and the arrangement of the catalyst cannot fully meet the reaction characteristics of the feedstock in different fractions, and the mutual interference of the different components of the olefins and the aromatic hydrocarbons in the reaction process is obvious, which will cause the insufficient hydrogenation of the components or the excessive hydrogenation of the different components, thereby causing the loss of the aromatic hydrocarbons, affecting the product quality and limiting the performance of the catalyst.

[0009] CN117126684A discloses a method for the deolefin of the reforming oil. The saturated hydrogen-dissolved reforming oil is sent into a first hydrogenation reactor, is first contacted with a nickel-containing catalyst, and the reaction products are then sent into a second hydrogenation reactor and are contacted with a noble metal catalyst, so as to effectively reduce the content of the olefins in the feedstock. However, the method cannot effectively control the saturation degree of the nickel catalyst to the aromatic hydrocarbons in the feedstock, and causes the loss of a large amount of the aromatic hydrocarbons. At the same time, the provision of two reactors increases the complexity of the flow, the equipment investment and the energy consumption. SUMMARY

[0010] In view of the deficiencies of the prior art, the present application provides a reforming oil hydrogenation deolefin device and process.

[0011] The reforming oil hydrogenation deolefin device of the present application comprises the following: a divided wall distillation column and a hydrogenation reactor; wherein the hydrogenation reactor comprises, from top to bottom, a reaction I zone, an upper hydrogen mixing zone, a separation zone, a lower hydrogen mixing zone and a reaction II zone; The divided wall distillation column is used to separate C7 and below light components, C8 components and C9+ heavy components in the raw material; the divided wall distillation column is provided with a vertical partition plate at the middle position of a conventional distillation column, and is provided with a common distillation section, a common stripping section, a distillation feed section on the two sides of the partition plate and a side line take-off section; the liquid phase outlets at the top, the side line and the bottom of the distillation column are connected to the upper hydrogen mixing zone, the separation zone and the lower hydrogen mixing zone of the hydrogenation reactor through pipelines; The reaction I zone is used for hydrogenation deolefin reaction of the first hydrogen mixing stream from the upper hydrogen mixing zone to obtain light component products; The upper hydrogen mixing zone is used for mixing C7 and below light components from the top of the divided wall distillation column, C8 components separated by the separation zone and hydrogen to obtain the first hydrogen mixing stream; The separation zone is used for further separating the C8 components from the side line of the divided wall distillation column, and the separated C8 components enter the upper hydrogen mixing zone upward, and the residual components (C9+ components) of the separation zone enter the lower hydrogen mixing zone downward; The lower hydrogen mixing zone is used for mixing C9+ heavy components from the bottom of the divided wall distillation column, the residual components of the separation zone and hydrogen to obtain the second hydrogen mixing stream, which pressurizes the liquid phase components on one hand and supplements the hydrogen required for the reaction to meet the reaction conditions and hydrogen consumption on the other hand; The reaction II zone is used for hydrogenation deolefin reaction of the second hydrogen mixing stream from the lower hydrogen mixing zone to obtain heavy component products.

[0012] In the device, the reaction I zone, the upper hydrogen mixing zone, the separation zone, the lower hydrogen mixing zone and the reaction II zone of the hydrogenation reactor are connected by pipelines between adjacent zones, and each zone is provided with a liquid phase inlet / outlet, a gas phase inlet / outlet and a flow control valve.

[0013] In the device, the reaction I zone is provided with a liquid phase outlet and a gas phase outlet at the upper portion, and is provided with a liquid phase inlet and a gas phase inlet at the lower portion and is connected to the upper hydrogen mixing zone through pipelines; the above inlets and outlets are provided with flow control valves; the gas phase inlet is provided with a hydrogen pipe distributor; and the liquid phase inlet is provided with a pressure spray distributor.

[0014] In the device, the reaction I zone adopts a Pt-Pd type catalyst with a hydrodeolefin function, γ-Al2O3 as a carrier, Pt and Pd as active components, the content of Pt is 0.01% to 0.2% and the content of Pd is 0.1% to 0.3% based on the total mass of the catalyst. The Pt-Pd type hydrodeolefin catalyst also contains an auxiliary component, such as at least one of boron, silicon, phosphorus, fluorine, sulfur, magnesium, titanium, calcium, etc., and the content of the auxiliary component is 6 wt% or less based on the total mass of the catalyst.

[0015] In the device, the top of the upper hydrogen mixing zone is provided with a liquid phase outlet and a gas phase outlet and connected to the reaction I zone through pipelines; the bottom is provided with a liquid phase inlet and connected to the separation zone through pipelines; one side of the upper hydrogen mixing zone (adjacent to the side of the divided wall column) is provided with a liquid phase inlet and connected to the top pipeline of the divided wall column through pipelines; the other side is provided with a gas phase inlet for hydrogen to enter; the above inlets and outlets are provided with flow control valves; a hydrogen tube distributor is arranged at the gas phase inlet; and a pressure spray distributor is arranged at the liquid phase inlet.

[0016] In the device, the separation zone adopts a narrow fraction separation mode, and the trays are arranged in the conventional plate type rectifying column, and the trays are arranged as narrow fraction extraction positions according to the requirements of the raw material reaction fraction section.

[0017] In the device, the top of the separation zone is provided with a liquid phase outlet and connected to the upper hydrogen mixing zone through pipelines; the bottom of the separation zone is provided with a liquid phase outlet and connected to the lower hydrogen mixing zone through pipelines; the side of the separation zone is provided with a liquid phase inlet and connected to the side line of the divided wall column through pipelines; the above inlets and outlets are provided with flow control valves, and the liquid phase inlet is provided with a pressure spray distributor.

[0018] In the device, the lower hydrogen mixing zone is used for mixing the C9+ heavy components from the bottom of the divided wall column and the residual components from the separation zone with hydrogen to obtain a second hydrogen mixing stream, which pressurizes the liquid phase components on one hand and supplements the hydrogen required for the reaction to meet the reaction conditions and hydrogen consumption on the other hand.

[0019] In the device, the top of the lower hydrogen mixing zone is provided with a liquid phase inlet and connected to the separation zone through pipelines; the bottom is provided with a liquid phase outlet and a gas phase outlet and connected to the reaction II zone through pipelines; one side of the lower hydrogen mixing zone (adjacent to the side of the divided wall column) is provided with a liquid phase inlet and connected to the bottom pipeline of the divided wall column through pipelines, and the other side is provided with a gas phase inlet for hydrogen to enter; the above inlets and outlets are provided with flow control valves, a hydrogen tube distributor is arranged at the gas phase inlet; and a pressure spray distributor is arranged at the liquid phase inlet.

[0020] In the device, the upper and lower hydrogen mixing zones are connected to the hydrogen inlet control valve through the interlocking control system to control the amount of hydrogen and the pressure in the hydrogen mixing zones; and hydrogen mixers are arranged in the upper and lower hydrogen mixing zones to realize gas-liquid mixing.

[0021] In the device, the upper part of the reaction II zone is provided with a liquid inlet and a gas inlet, and is connected to the lower hydrogen mixing zone through pipelines; the lower part of the reaction II zone is provided with a liquid outlet and a gas outlet; flow control valves are arranged on the inlets and outlets; and a hydrogen tube distributor is arranged on the gas inlet; and a pressure spray distributor is arranged on the liquid inlet.

[0022] In the device, the reaction II zone is provided with a non-noble metal NiO type hydrogenation catalyst with a hydrogenation and de-olefin function; the catalyst is supported on a porous oxide, preferably clover-shaped γ-Al2O3; the active metal component is selected from the group consisting of Group VIII metal oxides, preferably at least one selected from Co and Ni oxides, and preferably Ni-based oxides; the content of NiO is 10wt%-30wt% based on the total mass of the catalyst, preferably 15wt%-25wt%; and the non-noble metal NiO type hydrogenation catalyst preferably contains an auxiliary component, such as at least one selected from boron, silicon, phosphorus, fluorine, sulfur, magnesium, titanium, calcium, etc., and the content is 6wt% or less based on the total mass of the catalyst. Preferably, the content of the auxiliary component is 3wt%-5wt%.

[0023] The application also provides a reforming oil hydrogenation de-olefin process, which comprises the following steps: a reforming oil raw material is subjected to fractional distillation in a divided wall column to obtain C7 and below light components at the top of the column, C8 components in a side line, and C9+ heavy components at the bottom of the column; the C7 and below light components at the top of the column and the C8 components separated in a separation zone are subjected to hydrogenation in an upper hydrogen mixing zone and then enter a reaction I zone for hydrogenation de-olefin reaction, and light component products flow out from the top of the hydrogenation reactor; the C8 components in the side line enter the separation zone for narrow fraction secondary separation to obtain separation zone C8 components and residual components; the C9+ heavy components at the bottom of the column and the residual components separated in the separation zone are subjected to hydrogenation in a lower hydrogen mixing zone and then enter a reaction II zone for hydrogenation de-olefin reaction, and heavy component products flow out from the bottom of the hydrogenation reactor; and the light component products and the heavy component products are mixed to obtain a full fraction refined product.

[0024] In the process, the reforming oil raw material has the following properties: a distillation range of 70-200℃, a bromine index of ≯10000μg / g, a sulfur content of ≯0.5ppm, and a nitrogen content of ≯0.5ppm. The reforming oil raw material is generally reforming oil and / or aromatic gasoline.

[0025] In the process of this invention, the operating conditions of the wall-mounted distillation column are as follows: the operating pressure in the top zone is 0.5-1.5 MPa; the temperature is 80-110°C; the operating pressure in the bottom zone is 1.3-2.5 MPa; and the temperature is 120-140°C.

[0026] In the process of this invention, the operating conditions of the upper and lower hydrogen mixing zones of the hydrogenation reactor are as follows: feed temperature 30~180℃, preferably 50~160℃; pressure should be slightly higher than the pressure of the reaction zone to ensure that the reactant flows into the reaction zone, pressure 2.0~6.0MPa, preferably 3.0~5.0MPa, wherein the hydrogen partial pressure accounts for 100% of the total pressure.

[0027] In the process of this invention, the operating conditions of the separation zone of the hydrogenation reactor are as follows: the top temperature of the separation zone is 135℃~145℃, the top pressure is 0.08MPa~0.1MPa; the bottom temperature is 152℃~176℃, the bottom pressure is 0.11MPa~0.13MPa; and the reflux ratio is 2~5.

[0028] In the process of this invention, the operating conditions of reaction zone I of the hydrogenation reactor are as follows: reaction temperature 100℃~200℃, preferably 140℃~160℃; hydrogen partial pressure 1.0MPa~3.0MPa, preferably 1.5MPa~2.5MPa; volume hourly space velocity controlled at 1.0 h⁻¹. -1 ~15.0h -1 5.0h is preferred -1 ~10.0h -1 The hydrogen-to-oil volume ratio is controlled between 1:1 and 100:1, preferably between 30:1 and 80:1.

[0029] In the process of this invention, the operating conditions of the hydrogenation reactor in reaction zone II are as follows: reaction temperature 100℃~180℃; preferably 120~150℃; hydrogen partial pressure 2.0MPa~5.0MPa; preferably 2.5~4.0MPa; volume hourly space velocity controlled at 5.0h. -1 ~15.0h -1 Preferably 7.0h -1 ~12.0h -1 The hydrogen-to-oil volume ratio is controlled at 50:1 to 100:1, preferably 60:1 to 80:1.

[0030] In the process of this invention, the bromine index of the obtained whole fraction purified product is less than 300 mgBr / 100g, and the aromatic hydrocarbon loss is less than 0.1 wt%.

[0031] Compared with existing technologies, this method has the following advantages: The device and process can meet the industrial production requirement that C6-C8 fraction in full fraction reforming generated oil is "olefin is removed too much and aromatic is saturated too little" in the hydrogenation deolefin reaction process. The traditional flash separation technology will cause a small amount of C8 isomerized olefin in C7 and below component fraction, a small amount of C7 cyclic olefin in C8 fraction and C9+ heavy component, thereby increasing the competitive adsorption between components and increasing the reaction difficulty. The dividing wall column technology provided by the present application realizes the effective separation of C7 and below light component, C8 component and C9+ heavy component in the raw material by controlling the temperature and pressure in different areas of the column according to the raw material properties and reaction requirements, reduces the back mixing degree between the separated components and achieves the ideal separation purpose.

[0032] (2) The device and process of the present application separate the side line C8 component in the hydrogenation reactor separation zone to obtain a separation zone C8 component with a narrower distillation range and residual components, thereby further improving the separation degree between C8 and C9 components and avoiding the residual C9+ heavy component from entering the reaction I zone, thereby increasing the hydrogenation difficulty of the catalyst.

[0033] (3) The upper hydrogen mixing zone in the device and process of the present application is set according to the characteristics that the C7 and below light component at the top of the dividing wall rectifying column and the C8 component in the separation zone are fully hydrogenated and aromatic is avoided from being saturated in the hydrogenation process, the reaction conditions of the upper hydrogen mixing zone are reasonably set according to the raw material properties and product requirements, thereby providing the hydrogen amount required for the reaction of the light component raw material, avoiding the excessive hydrogenation of the raw material in this fraction to cause the excessive saturation of aromatic, thereby exerting the characteristics of the noble metal catalyst in reaction I zone, such as high activity and high selectivity, and realizing the reduction of chemical hydrogen consumption; the lower hydrogen mixing zone is set according to the characteristics that the C9+ heavy component at the bottom of the dividing wall rectifying column is difficult to process, the hydrogen is dissolved under pressure and the hydrogen required for the reaction is supplemented under the action of hydrogen, thereby improving the removal efficiency of olefin and aromatic in the heavy component.

[0034] (4) Compared with the processing mode of the traditional single-tower deolefin reaction device for full fraction reforming generated oil, the device and process of the present application set different zones in the hydrogenation reactor according to the reaction characteristics of different fraction raw materials, the back mixing degree between different fraction olefin and aromatic is effectively reduced by twice separation, the reaction conditions in the hydrogen mixing zone are reasonably set according to the olefin and aromatic content in light and heavy components and the processing difficulty, the hydrogen amount required for the reaction is provided and the reaction hydrogen partial pressure is met, different types of catalysts are set according to the raw material properties and the hydrogen amount required for the reaction, thereby avoiding the problem that the catalyst cannot be compatible with different component olefin reaction conditions and fully exerting the performance of the catalyst. At the same time, the hydrogenation reactor is set by function zoning and integrated, the amount of device equipment and the floor area in the traditional deolefin reaction process are reduced, the device energy consumption and usage are reduced, the production cost is effectively saved. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 A schematic diagram of a reforming generated oil hydrodeolefinization device and process of the present application.

[0036] Wherein, 1-reforming generated oil raw material, 2-new hydrogen, 3-dividing wall distillation column, 4-distillation column top C7 and below light components, 5-side line C8 components, 6-distillation column bottom C9+ heavy components, 7-reaction I zone, 8-upper mixed hydrogen zone, 9-separation zone, 10-lower mixed hydrogen zone, 11-reaction II zone, 12-separation zone C8 components, 13-separation zone residual components, 14-light component product, 15-heavy component product, 16-refined product. DETAILED DESCRIPTION

[0037] The present application is described in detail below in conjunction with the accompanying drawings and examples.

[0038] The reforming generated oil raw material 1 enters the dividing wall distillation column 3 after distillation treatment, and different distillate products enter different reaction zones of the hydrogenation reactor, wherein the distillation column top material C7 and below components 4 enter the upper mixed hydrogen zone 8 to be mixed with hydrogen 2 and then enter the reaction I zone 7 to undergo deolefinization reaction, obtaining the light component product 14; the side line C8 components 5 enter the separation zone 9 for narrow distillate secondary separation, and the separation zone C8 components 12 obtained by separation enter the upper mixed hydrogen zone 8 to be mixed with hydrogen and then enter the reaction I zone 7, and the separation zone residual components 13 flow out from the bottom of the separation zone to enter the lower mixed hydrogen zone 10 to be mixed with hydrogen and then enter the reaction II zone 11; the distillation column bottom material C9+ heavy components 6 enter the lower mixed hydrogen zone 10 to be mixed with hydrogen 2 and then enter the reaction II zone 11, and the heavy component product 15 is obtained by reaction, which is mixed with the light component product 14 to finally obtain the refined product 16.

[0039] In the actual use of the present application, the raw oil is reforming generated oil or aromatization gasoline, and a mixture of the two oil products.

[0040] The technical solutions of the present application will be described in detail below through specific examples. The present example test uses a set of small-sized dividing wall column micro device, a 100 mL fixed bed hydrogenation evaluation reaction device, and a hydrogenation reactor in which the reaction I zone, the upper mixed hydrogen zone, the separation zone, the lower mixed hydrogen zone, and the reaction II zone are sequentially arranged from top to bottom. The reaction I zone and the II zone are respectively filled with Pt-Pd noble metal catalyst and NiO hydrogenation catalyst, and the filling ratio is 1:3. The separation zone adopts a conventional plate-type distillation column structure. The mixed hydrogen zone is provided with a gas / liquid distributor, a gas flow control valve, and an interlocking system. The hydrogen source is externally supplied to evaluate the hydrogenation activity. The properties of the raw oil, the properties of the catalyst, the equipment parameters of the distillation column / separation zone / mixed hydrogen zone, the process conditions of the reaction zone, and the properties of the product are respectively shown in Tables 1, 2, 3, and 4.

[0041] Table 1 Feed oil product properties Item Reformate feedstock properties Density (20°C) kg / m 3 ]] 781.22 Distillation range °C 70～185 Bromine index mg / 100 g 3081 Olefin content m% 0.85 Aromatic content m% 63.18 Table 2 Catalyst physical and chemical parameters Name Pt-Pd catalyst NiO catalyst Shape Bar Clover shape Active metal Pt-Pd type NiO type Specific surface area m 2 / g]] 186.5 184.83 Pore volume mL / g 0.516 0.57 Diameter mm 1.3～1.6 1.0～1.5 Examples 1-2 This example is a set of small-scale divided wall column micro devices, a set of 100 mL fixed bed hydrogenation reaction devices, and the two devices are connected by pipelines. Pt-Pd type hydrogenation catalyst 20 mL is filled in reaction I zone for C8 and below component hydrogenation deolefin reaction, and 60 mL NiO type hydrogenation catalyst is filled in reaction II zone for liquid phase heavy component hydrogenation deolefin reaction. An outlet is provided above the hydrogenation reactor, which is connected to the reactor effluent, and then enters the high separator and low separator to obtain refined products.

[0042] Comparative Example 1 The existing method is used to carry out deolefin reaction on the reforming product oil. The raw material is mixed with hydrogen and directly introduced into a 100 mL fixed bed hydrogenation reactor for reaction. The raw material of this comparative example is the oil product of the example, and Pt-Pd type hydrogenation catalyst and NiO type hydrogenation catalyst are sequentially filled in the reactor, with a filling ratio of 1:3.

[0043] Comparative Example 2 The existing method is used to carry out deolefin reaction on the reforming product oil. Two 100 mL fixed bed hydrogenation reactors are connected in series, and the raw material is mixed with hydrogen and sequentially introduced into the 100 mL tubular hydrogenation reactor filled with NiO hydrogenation catalyst and Pt-Pd hydrogenation catalyst for reaction. The raw material of this comparative example is the oil product of the example, and the oil product is sequentially reacted through the two reactors, and then passes through the high separator, low separator and other processes to obtain refined products.

[0044] Comparative Example 3 The existing method is used to carry out deolefin reaction on the reforming product oil. The deolefin reaction is carried out as in the example. Compared with the example, the divided wall distillation column is replaced with a conventional flash separator and the separation zone in the hydrogenation reactor is removed in this comparative example. The raw material enters the separator, and the C8 / C9 fraction is used as the boundary. The C7 and below light components and C8 components are flashed and introduced into reaction I zone filled with Pt-Pd hydrogenation catalyst for reaction. The C9+ components are flashed and introduced into reaction II zone filled with NiO hydrogenation catalyst for reaction. The oil product is mixed and then sequentially passes through the high separator, low separator and other processes to obtain refined products.

[0045] Table 3 Fractionating column / separation zone / hydrogenation zone equipment parameters

[0046] Table 4 Performance comparison of examples and comparative examples

[0047] From the performance comparison in Table 4, it can be found that Comparative Example 1 and Comparative Example 2 adopt conventional fixed bed hydrogenation technology, and the pressure setting is relatively harsh. In the deolefin reaction, additional aromatic saturation is caused, and the presence of heavy aromatics in the whole distillate feedstock also has a certain adsorption effect on the olefin hydrogenation reaction. The olefin reaction in each distillate segment cannot be optimized, the reaction efficiency is reduced, the catalyst performance is wasted, and the service life is shortened.

[0048] From Table 4, it can be found that Comparative Examples 1 and 2 do not set the hydrogen mixer, and the hydrogen to oil volume ratio needs to be increased to meet the reaction hydrogen consumption, but it leads to insufficient oil liquefaction in the reactor, and the heavy components in the oil cannot completely enter the liquid phase components in the form of liquid to participate in the reaction, the reaction depth is insufficient, and the olefin removal is limited. In order to ensure product quality, the hydrogen to oil volume ratio must be increased, thereby increasing energy consumption and causing excessive saturation of aromatics.

[0049] From Table 4, it can be found that Comparative Example 1 limits the performance of each catalyst in the deolefin process by adopting a single reaction condition, and cannot target the reaction of olefins in each distillate segment of the feedstock. The reaction temperature and hydrogen make-up amount are relatively harsh, the aromatic loss in the feedstock is serious, and the olefin removal rate is poor. From Comparative Example 1 and Comparative Example 1, it can be found that the present method avoids the problem of insufficient processing of the feedstock caused by single reaction condition and insufficient performance of the catalyst by setting reaction zones. The setting of reaction zones optimizes the reaction conditions of each distillate feedstock, improves the adaptability of each catalyst, fully develops the performance, and reduces the harshness of the reaction.

[0050] From Table 4, it can be found that Comparative Example 2 sets reaction zones for processing the feedstock, but the light / heavy olefins and aromatic components in the feedstock are not separated, and the influence of each component olefin and aromatic and the competitive adsorption effect still exist. It is inevitable that there is insufficient olefin hydrogenation and excessive saturation of aromatics. The present example effectively separates the light / heavy olefins and aromatic components by setting a divided wall distillation column and a separation zone, taking the C8-C9 distillate as a boundary, and eliminates the influence of heavy component olefins and aromatics on the olefin hydrogenation reaction and the competitive adsorption effect.

[0051] From Table 4, under the same reaction device, reaction condition, and feed flow, and under the condition that ordinary flash separation is adopted and the hydrogenation reactor is not provided with a separation zone, it can be found from Comparative Example 1 and Comparative Example 3 that the C7 and below components and the C8 components obtained by flash separation enter reaction I zone, and there is residual C8+ heavy component interference, which leads to a decrease in the olefin removal rate and limits the catalyst performance, thereby affecting the overall olefin removal efficiency in the whole distillate feedstock. At the same time, due to the low separation accuracy, the feedstock of each distillate segment is severely mixed, causing the C7 and below components and the C8 components to flow into the heavy components, and the C7 and below components and the C8 components are excessively hydrogenated in the reaction II zone, causing excessive saturation of aromatics in the C7 and below components and the C8 components.

[0052] From the performance comparison in Table 4, it can be found that, under the same reaction conditions, compared with the conventional reformate selective hydrodeolefinization technology, the present method separates the raw material and sets partitions for the reactor, combines the olefin reaction characteristics of each fraction in the raw material, sets the reaction partitions and reaction conditions in a targeted manner, fully develops the reaction performance of the catalysts in each zone, improves the olefin removal efficiency in the raw material, and at the same time ensures the aromatic content in the product, providing ideas and methods for long-term stable operation of the subsequent device.

Claims

1. A reforming olefin hydrocracking unit characterized by The application relates to a hydrogenation reactor comprising a divided wall column and a hydrogenation reactor; wherein the hydrogenation reactor is sequentially provided with a reaction I zone, an upper mixed hydrogen zone, a separation zone, a lower mixed hydrogen zone and a reaction II zone from top to bottom. The divided wall column is used for separating C7 and below light components, C8 components and C9+ heavy components in raw materials; the top, side line and liquid phase outlet of the divided wall column are connected with the upper mixed hydrogen zone, the separation zone and the lower mixed hydrogen zone of the hydrogenation reactor through pipelines respectively. The reaction I zone is used for carrying out a hydrodeolefin reaction on a first mixed hydrogen stream from the upper mixed hydrogen zone to obtain light component products. The upper mixed hydrogen zone is used for mixing C7 and below light components from the top of the divided wall column, C8 components separated by the separation zone and hydrogen to obtain the first mixed hydrogen stream. The separation zone is used for further separating C8 components from the side line of the divided wall column; the separated C8 components enter the upper mixed hydrogen zone; the residual components (C9+ components) of the separation zone enter the lower mixed hydrogen zone. The lower mixed hydrogen zone is used for mixing C9+ heavy components from the bottom of the divided wall column, the residual components of the separation zone and hydrogen to obtain a second mixed hydrogen stream. The reaction II zone is used for carrying out a hydrodeolefin reaction on the second mixed hydrogen stream from the lower mixed hydrogen zone to obtain heavy component products.

2. The apparatus of claim 1, wherein: The reaction I zone, the upper mixed hydrogen zone, the separation zone, the lower mixed hydrogen zone and the reaction II zone of the hydrogenation reactor are connected through pipelines between adjacent zones; each zone is provided with a liquid phase inlet / outlet, a gas phase inlet / outlet and a flow control valve.

3. The apparatus of claim 1, wherein: The upper part of the reaction I zone is provided with a liquid phase outlet and a gas phase outlet; the lower part is provided with a liquid phase inlet and a gas phase inlet and is connected with the upper mixed hydrogen zone through pipelines; the inlets and outlets are provided with flow control valves; the gas phase inlet is provided with a hydrogen pipe type distributor; and the liquid phase inlet is provided with a pressure spray distributor.

4. The apparatus of claim 1, wherein: The reaction I zone adopts a Pt-Pd type catalyst with a hydrodeolefin function; gamma-Al2O3 is used as a carrier; Pt and Pd are used as active components; the content of Pt is 0.01% to 0.2% and the content of Pd is 0.1% to 0.3% based on the total mass of the catalyst; the Pt-Pd type hydrodeolefin catalyst preferably contains an additive component, which is at least one selected from boron, silicon, phosphorus, fluorine, sulfur, magnesium, titanium and calcium; and the content of the additive is less than 6wt% based on the total mass of the catalyst.

5. The apparatus of claim 1, wherein: The top of the upper mixed hydrogen zone is provided with a liquid phase outlet and a gas phase outlet and is connected with the reaction I zone through pipelines; the bottom is provided with a liquid phase inlet and is connected with the separation zone through pipelines; one side of the upper mixed hydrogen zone is provided with a liquid phase inlet and is connected with the pipeline of the top of the divided wall column through pipelines; the other side is provided with a gas phase inlet for hydrogen; the inlets and outlets are provided with flow control valves; the gas phase inlet is provided with a hydrogen pipe type distributor; and the liquid phase inlet is provided with a pressure spray distributor.

6. The apparatus of claim 1, wherein: The separation zone adopts a narrow fraction separation mode; trays are arranged in a conventional plate type rectifying column; and the trays are arranged as narrow fraction extraction positions according to the reaction fraction segment requirement of raw materials.

7. The apparatus of claim 1, wherein: The top of the separation zone is provided with a liquid phase outlet and is connected to the upper hydrogen mixing zone through a pipeline; the bottom of the separation zone is provided with a liquid phase outlet and is connected to the lower hydrogen mixing zone through a pipeline; the side of the separation zone is provided with a liquid phase inlet and is connected to the side line of the dividing wall column through a pipeline; the above inlets and outlets are provided with flow control valves, and the liquid phase inlet is provided with a pressure spray distributor.

8. The apparatus of claim 1, wherein: The top of the lower hydrogen mixing zone is provided with a liquid phase inlet and is connected to the separation zone through a pipeline; the bottom is provided with a liquid phase outlet and a gas phase outlet and is connected to the reaction II zone through a pipeline; one side of the lower hydrogen mixing zone is provided with a liquid phase inlet and is connected to the bottom pipeline of the dividing wall column through a pipeline, and the other side is provided with a gas phase inlet for hydrogen gas; the above inlets and outlets are provided with flow control valves, the gas phase inlet is provided with a hydrogen tube distributor, and the liquid phase inlet is provided with a pressure spray distributor.

9. The apparatus of claim 1, wherein: The pressure detection system in the upper and lower hydrogen mixing zones is connected to the opening degree control valve of the gas phase inlet to control the amount and pressure of hydrogen in the hydrogen mixing zone.

10. The apparatus of claim 1, wherein: The upper part of the reaction II zone is provided with a liquid phase inlet and a gas phase inlet and is connected to the lower hydrogen mixing zone through a pipeline, and the lower part is provided with a liquid phase outlet and a gas phase outlet; the above inlets and outlets are provided with flow control valves, the gas phase inlet is provided with a hydrogen tube distributor, and the liquid phase inlet is provided with a pressure spray distributor.

11. The apparatus of claim 1, wherein: The non-noble metal NiO type hydrogenation catalyst with hydrogenation and de-olefin function is used in the reaction II zone, the catalyst uses a porous oxide as a carrier, the porous oxide is preferably clover-shaped γ-Al2O3, the active metal component selects a Group VIII metal oxide, the Group VIII metal oxide is at least one selected from Co and Ni oxides, and is preferably a Ni-based oxide; the NiO content is 10wt%-30wt% based on the total mass of the catalyst, and is preferably 15wt%-25wt%; the non-noble metal NiO type hydrogenation catalyst preferably contains an auxiliary component, which is at least one selected from boron, silicon, phosphorus, fluorine, sulfur, magnesium, titanium and calcium, and the content is 6wt% or less based on the total mass of the catalyst.

12. A hydrodeoxygenation process for reforming a generated oil, characterized in that The following contents are included: the reforming generated oil raw material enters the dividing wall column and is subjected to fractionation treatment to obtain C7 and below light components at the top of the dividing wall column, C8 components at the side line and C9+ heavy components at the bottom of the dividing wall column; the C7 and below light components at the top of the dividing wall column and the C8 components separated in the separation zone enter the upper hydrogen mixing zone and are subjected to hydrogenation treatment to enter the reaction I zone for hydrogenation and de-olefin reaction, and light component products flow out from the top of the hydrogenation reactor; The C8 components at the side line enter the separation zone for narrow fraction secondary separation to obtain C8 components and residual components in the separation zone; the C9+ heavy components at the bottom of the dividing wall column and the residual components separated in the separation zone enter the lower hydrogen mixing zone and are subjected to hydrogenation to enter the reaction II zone for hydrogenation and de-olefin reaction, and heavy component products flow out from the bottom of the hydrogenation reactor, are mixed with the light component products flowing out from the top, and full-range refined products are obtained.

13. The process of claim 12, wherein: The reforming generated oil raw material has the following properties: the distillation range is 70-200℃, the bromine index is ≯10000μg / g, the sulfur content is ≯0.5ppm, and the nitrogen content is ≯0.5ppm.

14. The process of claim 12, wherein: The operating conditions of the divided wall rectification column are as follows: the operating pressure of the top zone is 0.5-1.5 MPa; the temperature is 80-110 ℃; the operating pressure of the bottom zone is 1.3-2.5 MPa; and the temperature is 120-140 ℃.

15. The process of claim 12, wherein: The operating conditions of the upper and lower hydrogen mixing zones of the hydrogenation reactor are as follows: the feed temperature is 30-180 ℃, preferably 50-160 ℃; the pressure should be slightly higher than that of the reaction zone to ensure that the reactant flow enters the reaction zone, and the pressure is 2.0-6.0 MPa, preferably 3.0-5.0 MPa, wherein the hydrogen partial pressure accounts for 100% of the total pressure.

16. The process of claim 12, wherein: The operating conditions of the separation zone of the hydrogenation reactor are as follows: the top temperature of the separation zone is 135-145 ℃, the top pressure is 0.08-0.1 MPa; the bottom temperature is 152-176 ℃, and the bottom pressure is 0.11-0.13 MPa; and the reflux ratio is 2-5.

17. The process of claim 12, wherein: The operating conditions of the reaction I zone of the hydrogenation reactor are as follows: reaction temperature 100-200°C, preferably 140-160°C; reaction hydrogen partial pressure 1.0-3.0 MPa, preferably 1.5-2.5 MPa; volume space velocity controlled at 1.0-15.0 h -1 -1 -1 0 h -1 -1 -1 0 h; hydrogen / oil volume ratio controlled at 1:1-100:1, preferably 30:1-80:

1.

18. The process of claim 12, wherein: The hydrogenation reactor reaction II zone operating conditions are: reaction temperature 100-180°C; preferably 120-150°C; reaction hydrogen partial pressure 2.0-5.0 MPa; preferably 2.5-4.0 MPa; volume space velocity controlled at 5.0-15.0 h -1 -1 -1 , preferably 7.0-12.0 h -1 -1 -1 , hydrogen oil volume ratio controlled at 50:1-100:1, preferably 60:1-80:1.

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