Background
Hydrogenation is a reaction process in which hydrogen interacts with compounds, usually in the presence of a catalyst. Hydrogenation processes have been one of the most important reaction processes in the chemical industry and petroleum refining industry. The hydrogenation reaction is reversible, exothermic and the number of molecules is reduced, and the chemical equilibrium is favorably shifted to the direction of the hydrogenation reaction at low temperature and high pressure. The temperature required for the hydrogenation process depends on the activity of the catalyst used, and temperatures at which the activity is high may be lower. For the hydrogenation reaction with a small equilibrium constant under the reaction temperature condition, the reaction process needs to be carried out under high pressure in order to increase the equilibrium conversion rate, and is also favorable for increasing the reaction speed. In addition, excessive hydrogen is adopted, so that the reaction speed can be accelerated, the conversion rate of hydrogenated substances can be improved, and the reaction heat can be led out. The excess hydrogen can be recycled.
Hydrogenation reactors are classified into various types, such as fixed bed hydrogenation reactors, suspended bed hydrogenation reactors, ebullated bed hydrogenation reactors, and the like, and the fixed bed hydrogenation reactor is most widely applied. The upflow fixed bed reactor can treat various types of oil products, and has unique advantages in the oil product hydrogenation process, such as poor oil product residual oil and coal liquefied oil, which are easily poisoned by hydrogenation catalysts or quickly inactivated by catalyst pore channel blockage due to high impurity content, and the impurities may block the bed layer to quickly raise the pressure drop to cause the working condition of the reactor to be worsened, even the normal operation cannot be realized, if the upflow hydrogenation process is adopted to cause the gas-liquid cocurrent upward movement to cause the expansion of the catalyst bed layer, the void ratio of the bed layer can be increased, and the blockage of the catalyst bed layer is avoided. In the hydrogenation process, compared with the traditional fixed bed gas/liquid/solid three-phase hydrogenation process, the liquid phase hydrogenation process has the advantages of high hydrogenation reaction rate, high reaction efficiency, low energy consumption, low investment and the like, and is widely accepted and applied, so that the up-flow liquid phase hydrogenation process integrates the advantages of an up-flow hydrogenation reactor and the advantages of a liquid phase hydrogenation process, and has certain advantages when being applied to the hydrogenation process. However, the following problems still exist in the conventional upflow liquid phase hydrogenation reactor and reaction process: (1) The contact between the reaction materials and the catalyst is more sufficient, the reaction rate is high, the reaction efficiency is high, and the problems of long reaction residence time, side reaction or severe cracking and catalyst coking still exist; (2) Especially in the section with high reaction temperature in the final stage, because the contact between the materials and the catalyst is sufficient, the side reaction or the cracking reaction is serious and far exceeds the positive reaction, a large amount of undesired reactions occur in the final stage of the reaction, and the yield and the production efficiency are reduced; (3) Along with the flow of materials in the hydrogenation reactor and the consumption of hydrogen in the reaction process, the dissolution and dispersion state of hydrogen in oil products is gradually changed, so that hydrogen bubbles dissolved around oil product molecules are reacted, and the bubbles which do not react are gradually agglomerated into large bubbles, so that the hydrogen can not be continuously provided in the hydrogenation reaction process of the oil products, and side reactions or cracking reactions can also be increased; (4) At the end of the reaction, some hydrogenation reactions have an inhibitory effect on the positive reaction of the product or one or more components in the product, making it difficult to achieve the desired depth of hydrogenation reaction. Therefore, for the conventional upflow liquid phase hydrogenation reaction process, effective means such as development of a new hydrogenation method and a new reactor form are adopted, the hydrogenation reaction rate and the reaction depth are improved, and the side reaction or the cracking reaction at a high temperature section is inhibited, so that the method has important significance.
CN202063881U discloses a liquid phase hydrogenation reactor, wherein a mixer is arranged in a top head of the reactor, the mixer is provided with a mixed oil feeding hole and a hydrogen inlet, a dissolved hydrogen mixture outlet and a gas outlet, and the mixture dissolved hydrogen mixture outlet is inserted into the liquid phase of the reactor. The purpose of this patent is through the structure of hydrogen mixer in the reactor, to increase the gas-liquid phase contact area, make hydrogen dissolve in the miscella, improve hydrogenation efficiency.
CN105713659A proposes a continuous liquid phase hydrogenation process for hydrocarbons, in which hydrocarbon raw materials and hydrogen are fully mixed by a gas-liquid mixer to form a liquid phase material flow saturated with dissolved hydrogen, hydrogen is injected into a reactor containing at least two stages of catalysts from top to bottom in sequence with a hydrogen distributor at the lower part of each stage of catalyst, and the product is led out of the reactor for subsequent treatment. The aim of the method is to reduce the amount of fresh hydrogen in the catalyst bed, i.e. to increase the reaction efficiency.
CN200810117101.1 proposes an upflow reactor and application thereof, the upflow reactor comprises an initial distributor positioned at the bottom of the reactor and a middle distributor positioned above the initial distributor, the initial distributor consists of a conical baffle plate and a sieve plate positioned above the conical baffle plate; the intermediate distributor is composed of an open-pore sieve plate and a sieve plate string structure, and the upflow reactor provided by the invention aims to realize uniform distribution of gas, thereby improving the utilization rate of the catalyst. CN201110353672.7 provides a gas-liquid distributor of an upflow reactor and application thereof, and the gas-liquid distributor comprises a distribution disc tower plate and a cap type gas collection distributor. CN201510697566.9 proposes an upflow distributor and an upflow reactor, and the purpose of the invention is that the fluid can be uniformly distributed and uniformly mixed after passing through the upflow distributor by the technical scheme.
In summary, in the upflow hydrogenation reactor and the liquid phase hydrogenation reactor in the prior art, hydrogen dissolution is generally performed by a hydrogen dissolution method or a hydrogen dissolution component, and the reaction efficiency is improved by a hydrogen supplementation method, so that the problems of high catalytic activity in the early stage and the middle stage of the reaction, low reaction rate in the final stage, serious side reaction and cracking reaction of the upflow liquid phase hydrogenation reactor, inhibition of reaction products on reaction raw materials, and the like are not solved.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a hydrogenation reactor and a hydrogenation method, wherein the inner cylinder with a conical structure is arranged in the upflow hydrogenation reactor, so that the contact time of materials and different active catalysts in different temperature sections of the hydrogenation reaction can be effectively controlled, the purposes of realizing rapid reaction in low and medium temperature sections and inhibiting side reaction in a high temperature section are realized, and the hydrogenation reaction rate and the reaction depth are improved.
The hydrogenation reactor comprises an inner cylinder and a reactor shell, wherein the inner cylinder is conical, and an annular space with a gradually reduced cross-sectional area is formed between the inner cylinder and the reactor shell from top to bottom; the top and the bottom of the inner cylinder are open, and the edge of the bottom is hermetically connected with the inner wall of the reactor; the inner cylinder is filled with a hydrogenation catalyst I, the annular space is filled with a hydrogenation catalyst II, and the activity of the hydrogenation catalyst I is higher than that of the hydrogenation catalyst II; the middle part of the reactor is horizontally provided with a hydrogen replenishing component, the hydrogen replenishing component penetrates through the annular space and the cross section where the inner cylinder is located, and the hydrogen replenishing component is communicated with external hydrogen; the reactor raw material inlet is communicated with the bottom of the inner cylinder, and the reactor product outlet is communicated with the lower part of the annular space; the material flows from bottom to top in the inner cylinder; the material flows from top to bottom in the annular space.
The ratio of the diameter of the top plane of the inner cylinder to the diameter of the reactor is (1.05-1), preferably (1.5-1).
The hydrogenation reactor comprises a hydrogen supplementing assembly and a hydrogen distribution or gas-liquid mixing assembly, wherein the hydrogen supplementing assembly comprises a pipeline communicated with external hydrogen and the hydrogen distribution or gas-liquid mixing assembly. The component with the gas distribution function, such as a distribution pipe, a distribution plate and the like, can also be equipment with the gas-liquid mixing function, such as a static mixer filled with any one of a spiral plate, a corrugated plate, a rotating blade, a flat blade, a bent blade or a porous plate, or a microporous plate nano/micron hydrogen dispersion component, a ceramic membrane nano/micron hydrogen dispersion component and the like. And the hydrogen replenishing assembly of the inner barrel part and the hydrogen replenishing assembly of the annular space part are respectively communicated with an external hydrogen pipeline.
In the hydrogenation reactor, the hydrogen supplement component is preferably a ceramic membrane nano/micron dispersion component which is of an integrated tube-shell structure and generally comprises a plurality of ceramic membrane tubes and a shell, wherein the ceramic membrane tubes are perpendicular to the cross section of the reactor, two ends of each membrane tube are fixed on a tube plate, and the shell is fixed on the inner surface of the reactor; the ceramic membrane nano/micron dispersion component of the inner cylinder part, the membrane tube is communicated with the material flowing upwards in the inner cylinder, and the cavity outside the membrane tube is communicated with an external hydrogen pipeline; a ceramic membrane nano/micron dispersion component in the annular space, wherein a membrane tube is communicated with an external hydrogen pipeline, and a cavity outside the membrane tube is communicated with a material flowing downwards in the annular space; the ceramic membrane nano/micro hydrogen dispersion module is capable of forming nano/micro bubble hydrogen with a size of generally 10 to 1000nm, preferably 50 to 500nm.
According to the hydrogenation reactor, the ceramic membrane nano/micron dispersion assembly at the inner cylinder part and the ceramic membrane nano/micron hydrogen dispersion assembly positioned at the inner cylinder mainly have the functions of hydrogen supplement and hydrogen re-dissolution, materials at the lower part of the inner cylinder enter the inside of the membrane tube, hydrogen enters the outside of the membrane tube through an external hydrogen pipeline, the hydrogen permeates and diffuses into the inside of the tube through the outside of the membrane tube and is mixed and dissolved with the materials in the inner cylinder to be hydrogen-containing materials, and the hydrogen flows out of the membrane tube, so that the driving force of the hydrogenation reaction process at low and medium temperature sections is enhanced to maintain higher reaction rate; the ceramic membrane nano/micron hydrogen dispersion assembly in the annular space has the main functions of hydrogen supplement and stripping, materials flowing downwards in the upper part of the annular space enter the outside of the membrane tube, hydrogen enters the inside of the membrane tube through an external hydrogen pipeline, and in the process that the hydrogen permeates and diffuses to the outside of the membrane tube through the outside of the tube, the materials are mixed and dissolved with the materials outside the membrane tube to form the materials containing the hydrogen, and the stripping effect is performed on the materials through the external diffusion of the hydrogen, so that the hydrogen can be supplemented in the final reaction stage, the coking of the surface of a catalyst in the high-temperature section in the final reaction stage is inhibited, and meanwhile, a surface coking precursor and the generated gas in a reactor can be timely stripped and separated, and the reaction depth is improved.
In the hydrogenation reactor, the top is a reactor upper end enclosure, the bottom is a reactor lower end enclosure, and a material distributor is preferably arranged at a raw material inlet and used for uniformly distributing materials to enter the inner cylinder.
The hydrogenation method comprises the following steps: the raw material containing hydrogen enters the conical inner cylinder through a feed inlet at the bottom of the reactor, and is subjected to hydrogenation reaction with the hydrogenation catalyst I filled in the inner cylinder, the material is subjected to hydrogen supplementation and hydrogen re-dissolution through the hydrogen supplementation component, flows out from the top of the inner cylinder, passes through the top of the reactor, enters the annular space from top to bottom, is subjected to further hydrogenation reaction with the hydrogenation catalyst II filled in the annular space, the material flow is subjected to hydrogen supplementation and steam stripping through the hydrogen supplementation component, and the final reaction product is discharged from a discharge outlet at the bottom of the reactor.
In the method, the hydrogen replenishing amount of the inner cylinder and the annular space is regulated according to the requirement of the reaction process, and the ratio of the hydrogen replenishing amount of the inner cylinder to the hydrogen replenishing amount of the annular space is (1-1), preferably (1).
In the method, the retention time ratio of the materials in the inner cylinder and the annular space is 100 to 1, preferably 30.
In the method, the top of the reactor is provided with a gas space, and the highest point of the head at the top of the reactor is provided with a gas outlet for continuously or discontinuously discharging the reaction gas stripped in the reaction process.
In the method, the upper part of the reactor is discharged by liquid level control, so that the hydrogenation reaction process is ensured to be full liquid phase hydrogenation.
In the method, the hydrogenation reaction conditions of the inner cylinder are as follows: the reaction temperature is 60-360 ℃, preferably 180-340 ℃; the reaction pressure is 0.5MPa to 20.0MPa, preferably 2.0MPa to 6.0MPa; fresh feed liquid hourly space velocity of 0.5h -1 ~10.0h -1 Preferably 1.0h -1 ~6.0h -1 。
In the method of the invention, the hydrogenation reaction conditions of the annular space are as follows: the reaction temperature is 120-400 ℃, preferably 220-380 ℃; the reaction pressure is 0.5MPa to 20.0MPa, preferably 2.0MPa to 6.0MPa; fresh feed liquid hourly space velocity of 0.5h -1 ~15.0h -1 Preferably 3.0h -1 ~10.0h -1
The hydrogenation reactor can be used for various raw materials which can be subjected to hydrogenation reaction with hydrogen in the field of petrochemical industry, and can be crude oil and secondary processing oil such as crude oil, gasoline, kerosene, diesel oil, residual oil, heavy oil, wax oil, lubricating oil, deasphalted oil, biodiesel, animal oil or vegetable oil, coal tar, anthracene oil and the like, wherein reactions such as hydrogenation conversion of sulfur/nitrogen/oxygen/metal and the like, olefin and diene hydrogenation saturation, aromatic hydrocarbon partial hydrogenation saturation, hydrocracking and the like are performed in the hydrogenation process; the catalyst can also be various raw materials capable of undergoing hydrogenation reaction in the chemical field, and can be raw materials containing carbon-carbon double bonds, carbon-carbon triple bonds and organic functional groups, such as olefin hydrogenation, alkyne hydrogenation, aldehyde compound hydrogenation, ketone compound hydrogenation, ester compound hydrogenation, nitro compound hydrogenation, nitrile compound hydrogenation and the like.
In the method of the present invention, the activity of the hydrogenation catalyst I is higher than that of the hydrogenation catalyst II, and preferably, the ratio of the activity of the hydrogenation catalyst I to the activity of the hydrogenation catalyst II is 1.05 to 10. The level of activity is expressed by the amount of reactants converted into raw materials per unit volume (or mass) of the catalyst in unit time, and can be selected or regulated in the preparation process through the specific surface area of the catalyst carrier, the nature of active centers on the surface, the amount of active centers on the unit surface area and the like.
The catalyst activity was evaluated as follows: under the same raw material composition and reaction conditions, the same volume of catalyst is subjected to hydrogenation reaction on the same set of device, the product composition data is determined after the same retention time, and the conversion rate is calculated and compared to be used as the basis for judging the activity.
In the method of the invention, the catalyst adopted by the hydrogenation reactor can use proper hydrogenation catalyst according to the reaction requirement to realize different hydrogenation purposes, such as hydrofining catalyst, prehydrogenation refining catalyst, hydrogenation modification catalyst, selective hydrogenation catalyst, hydrotreating catalyst, hydrocracking catalyst, supplementary hydrogenation catalyst and the like, and various catalysts can be selected from commercial catalysts and can also be prepared according to the prior art. The catalytic reaction can remove the impurities such as sulfur, nitrogen, oxygen, arsenic, metal, carbon residue and the like in part or all of the hydrocarbon raw materials, or saturated/partially saturated olefin, aromatic hydrocarbon and diene, or the reactions such as hydrocarbon molecular isomerization, alkylation, cyclization, aromatization, cracking and the like; the catalyst active component includes but is not limited to one or more combinations of noble metals, co, mo, ni, W, mg, zn, rare earth elements and the like.
In the method, the annular space can be filled with a hydrogenation catalyst with activity which is wholly or partially lower than that of the inner cylinder, and the catalyst can be a commercially available product or prepared according to conventional knowledge in the field; for example, a catalyst with high hydrodesulfurization activity can be used, which generally uses alumina or silicon-containing alumina as a carrier and Mo and Co as hydrogenation active components. Based on the weight of the catalyst, the content of the metal Mo is 6-20 wt% calculated by oxide, and the content of the metal Co is 1-12 wt% calculated by oxide.
For a conventional hydrogenation reaction process, firstly, most of the hydrogenation reaction processes are exothermic reactions, that is, the temperature is gradually increased along with the reaction, although the higher the temperature is, the faster the reaction rate is, when the temperature is higher, the material is more prone to coking on the surface of the catalyst, so that a cracking reaction occurs or the activity of the catalyst is reduced, therefore, along with the increase of the hydrogenation reaction temperature, the contact time of the raw material and the high-efficiency catalyst should be gradually shortened, and the coking on the surface of the catalyst is slowed or controlled while the higher reaction is maintained; in the second aspect, in the later stage of the hydrogenation reaction, the reaction temperature is high, the high-activity catalyst is more prone to coking under the condition of high temperature, and the cracking reaction is more serious, so that a catalyst with proper activity or even slightly low activity is filled in the last stage of the reaction, the hydrogenation reaction rate is controlled as much as possible, the high reaction rate in the later stage of the reaction is inhibited, and in the later stage of the reaction, along with the increase of the hydrogenation reaction temperature, the retention time of the raw material on the surface of the catalyst is gradually shortened to control the coking on the surface of the catalyst; in the third aspect, some byproduct reaction gases have a certain inhibiting effect on hydrogenation reaction, and the byproduct reaction gases cannot be removed out of the system in time and are not beneficial to deep hydrogenation reaction, so that in-situ stripping in the reaction process plays an important role in realizing deep hydrogenation; in the fourth aspect, in the low and medium temperature stages, the hydrogenation reaction rate is high, the hydrogen consumption is high, the dissolution dispersion state of the hydrogen in the raw material has been gradually changed, so that the hydrogen bubbles dissolved around the oil molecules have been reacted, and those bubbles which have not reacted gradually coalesce into large bubbles, so that the oil cannot continuously provide hydrogen in the hydrogenation reaction process, the continuous driving force of the reaction hydrogen is reduced, and the reaction rate is reduced, therefore, the dissolved hydrogen in the high dispersion state needs to be timely supplemented in the low and medium temperature stages of the reaction.
According to the invention, through a special hydrogenation reactor structure and a hydrogenation reaction method, the contact time of materials and different active catalysts in different temperature sections of the hydrogenation reaction is effectively controlled, the purposes of quick reaction in low and medium temperature sections and inhibition of side reaction in a high temperature section are realized, and the hydrogenation reaction rate and the reaction depth are improved. The hydrogenation reactor comprises a conical inner cylinder, an annular space with the cross sectional area gradually reduced from bottom to top and a hydrogen replenishing assembly penetrating through the inner cylinder and the annular space, wherein the material flows from bottom to top in the conical inner cylinder, and the contact time of the raw material and the high-activity catalyst is controlled to be gradually shortened along with the rise of the reaction temperature by utilizing the characteristic that the cross sectional area of a conical structure is gradually reduced from bottom to top, so that the coking on the surface of the catalyst is slowed or controlled while the high reaction is kept, and the side reaction is reduced; the flowing mode of the material in the annular space is from top to bottom, and the characteristic that the sectional area of the annular space is gradually reduced from top to bottom is utilized, so that the contact time of the control raw material and the catalyst with low activity is gradually shortened when the temperature at the final stage of reaction is higher, and the high-temperature coking on the surface of the catalyst can be further inhibited and slowed or controlled, and the side reaction is reduced. In addition, a high-activity catalyst is adopted at the low and medium temperature reaction stages of the conical inner cylinder, rapid hydrogenation reaction occurs, hydrogen is supplemented through a hydrogen supplementing component in the reaction process, when high hydrogen consumption in the reaction process is achieved, high-dispersion hydrogen is supplemented in time, the driving force of the hydrogenation reaction process is increased, and the medium and low temperature hydrogenation reaction rates are further improved; and a catalyst with slightly low activity is filled in the annular space at a high temperature stage to perform a slow hydrogenation reaction, and hydrogen is supplemented through the hydrogen supplementing component in the reaction process to play roles of supplementing hydrogen and stripping, so that the coking of the catalyst at the high temperature reaction stage is inhibited, and the reaction gas for inhibiting the hydrogenation reaction is stripped to achieve a deep hydrogenation reaction.
Detailed Description
The invention is described in detail below with reference to the figures and examples, but the invention is not limited thereby.
The hydrogenation reactor and hydrogenation process of the present invention are illustrated in FIG. 1:
raw oil 1 and hydrogen 2 are mixed by a hydrogen-oil mixer 3, and then enter a hydrogenation reactor 5 from the bottom of the hydrogenation reactor 5 as a hydrogenation reactor feed 4, firstly enter a conical inner cylinder 12 of the hydrogenation reactor 5, sequentially pass through a hydrogenation catalyst I from bottom to top for hydrogenation reaction, enter a region where the top of the reactor is communicated with the inner cylinder, and carry out hydrogen supplementation and hydrogen re-dissolution by a hydrogen supplementation component (ceramic membrane nano/micron hydrogen dispersion component) 16 in the reaction process of the conical inner cylinder 12; the material leaving the conical inner cylinder 12 enters an annular space 14, and is subjected to further hydrogenation reaction with a hydrogenation catalyst II15 in the annular space from top to bottom, and in the reaction process, hydrogen supplement and stripping reaction gas are performed through a hydrogen supplement component (ceramic membrane nano/micron hydrogen dispersion component) 16, so that the reaction gas in the reaction product is stripped while the coking of the high-temperature catalyst is prevented; the final reaction product 6 leaves the hydrogenation reactor 5 under the control of a reaction product discharge valve 8; the reaction gas stripped from the annular space 14 is discharged as an exhaust gas 7 by the reactor top exhaust control valve 9. The hydrogen supplement component (ceramic membrane nano/micron dispersion component) 16 is an integrated tube shell structure and generally comprises a plurality of ceramic membrane tubes and a shell, wherein the ceramic membrane tubes generally comprise a plurality of ceramic membranes perpendicular to the cross section of the reactor, two ends of each membrane tube are fixed on a tube plate, and the shell is fixed on the inner surface of the reactor; a ceramic membrane nano/micron dispersion component 16 at the inner cylinder part, a membrane tube 16 is communicated with materials flowing upwards in the inner cylinder, and a cavity at the outer side of the membrane tube is communicated with an external hydrogen pipeline 20; a ceramic membrane nano/micron dispersion component 16 at the annular space part, a membrane tube 19 is communicated with an external hydrogen pipeline 17, and a cavity at the outer side of the membrane tube is communicated with a material flowing downwards in the annular space; in the hydrogenation reaction process, the ceramic membrane nano/micron dispersion component 16 at the inner cylinder part is a material from the lower part of the inner cylinder enters the membrane tube, hydrogen enters the outside of the membrane tube through an external hydrogen pipeline, and the hydrogen permeates and diffuses into the tube through the outside of the tube and is mixed with the material in the inner cylinder to be dissolved into a material containing the hydrogen and flows out of the membrane tube and flows downwards to generate the hydrogenation reaction; the ceramic membrane nanometer/micrometer dispersion assembly 16 of the annular space is that the supplies from the annular space enter the outside of the tube of membrane tube, hydrogen enters the tube of the tube 19 of membrane tube through the outside hydrogen pipeline 17, in the course that the hydrogen permeates and diffuses outside the tube through the tube, mix and dissolve with the supplies outside the tube as the supplies comprising hydrogen, carry on the stripping action to the supplies through the outer diffusion of hydrogen, can supplement hydrogen for the reaction later stage, inhibit the catalyst surface coking of high-temperature section of later stage from coking, can separate surface coking precursor and inhibit the timely stripping of the reactor forming gas at the same time, improve and strengthen the depth of reaction.
The raw oil used in the comparative example and the example of the invention is straight-run diesel oil and catalytic diesel oil from a certain plant, and the specific properties are shown in Table 1.
TABLE 1 Properties of the raw materials
Comparative example 1
A conventional fixed bed hydrogenation reactor and a hydrogenation method are adopted, and a static mixer is adopted as hydrogen-oil mixing equipment, wherein the model is as follows: SX-2.3-10.0-500; the hydrogen feed in the reactor feed was 0.63% by mass of the feed oil (sum of fresh feed oil and cycle oil). The hydrogenation reactor adopts a catalyst FHUDS-5 of the comforting petrochemical research institute.
The fixed bed hydrogenation reaction conditions were as follows: the reaction temperature is 340-388 ℃, the reaction pressure is 6.5MPaG, the liquid hourly space velocity is 3.0h < -1 >, and the circulation ratio is 1.5-2.0.
The straight-run diesel oil and the catalytic diesel oil in the table 1 are respectively used as raw materials, and reaction products are obtained after fixed bed liquid phase hydrogenation, and the reaction conditions and the product properties are shown in tables 2 and 3.
Example 1
By adopting the method shown in the attached figure 1, the catalyst adopted by the conical inner cylinder of the hydrogenation reactor is FHUDS-5 of the comforting petrochemical research institute, and the catalyst adopted by the annular space is FH-40C; the hydrogen contained in the feeding material of the hydrogenation reactor is 0.31 percent of the mass of the raw oil (the sum of the fresh raw oil and the circulating oil), the hydrogen supplement amount in the conical inner cylinder of the hydrogenation reactor is 0.24 percent of the mass of the raw oil (the sum of the fresh raw oil and the circulating oil), and the hydrogen supply amount in the annular space is 0.05 percent of the mass of the raw oil (the sum of the fresh raw oil and the circulating oil). The reaction conditions of the conical inner cylinder of the hydrogenation reactor are as follows: the reaction temperature is 300-340 ℃, the reaction pressure is 6.0MPaG, and the liquid hourly space velocity is 5.0h -1 (ii) a The reaction conditions of the annular space are as follows: the reaction temperature is 330-358 ℃, the reaction pressure is 5.9MPaG, and the liquid hourly space velocity is 6.0h -1 . The ratio of the top plane diameter of the inner tapered cylinder in the reactor to the diameter of the reactor was 1.
The straight-run diesel oil and catalytic diesel oil in table 1 are used as raw materials, and reaction products are obtained after fixed bed liquid phase hydrogenation, and the reaction conditions and the product properties are shown in tables 2 and 3.
Example 2
The method shown in the attached figure 1 is adopted, wherein a catalyst adopted by the conical inner cylinder of the hydrogenation reactor is FHUDS-2 of the comforting petrochemical research institute, and a catalyst adopted by the annular space is FH-40C; the hydrogen contained in the feeding material of the hydrogenation reactor is 0.26 percent of the mass of the raw oil (the sum of the fresh raw oil and the circulating oil), the hydrogen supplement amount in the conical inner cylinder of the hydrogenation reactor is 0.28 percent of the mass of the raw oil (the sum of the fresh raw oil and the circulating oil), and the hydrogen supply amount in the annular space is 0.06 percent of the mass of the raw oil (the sum of the fresh raw oil and the circulating oil). The reaction conditions of the conical inner cylinder of the hydrogenation reactor are as follows: the reaction temperature is 315-352 ℃, the reaction pressure is 6.0MPaG, and the liquid hourly space velocity is 4.5h -1 (ii) a The reaction conditions of the annular space are as follows: the reaction temperature is 340-372 ℃, the reaction pressure is 5.9MPaG, and the liquid hourly space velocity is 7.5h -1 . The ratio of the top plane diameter of the inner tapered cylinder in the reactor to the diameter of the reactor was 1.
The straight-run diesel oil and the catalytic diesel oil in the table 1 are used as raw materials, and reaction products are obtained after fixed bed liquid phase hydrogenation, and the reaction conditions and the product properties are shown in tables 2 and 3.
Example 3
Adopting the method shown in the attached figure 1, the catalyst adopted by the conical inner cylinder of the hydrogenation reactor is FHUDS-5 of the comforting petrochemical research institute, and the catalyst adopted by the annular space is FHUDS-2; the hydrogen contained in the feeding of the hydrogenation reactor is 0.22 percent of the mass of the raw oil (the sum of the fresh raw oil and the circulating oil), the hydrogen supplement amount in the conical inner cylinder of the hydrogenation reactor is 0.31 percent of the mass of the raw oil (the sum of the fresh raw oil and the circulating oil), and the hydrogen supply amount in the annular space is 0.07 percent of the mass of the raw oil (the sum of the fresh raw oil and the circulating oil). The reaction conditions of the conical inner cylinder of the hydrogenation reactor are as follows: the reaction temperature is 318-348 ℃, the reaction pressure is 5.5MPaG,the liquid hourly space velocity is 5.0h -1 (ii) a The reaction conditions of the annular space are as follows: the reaction temperature is 338-375 ℃, the reaction pressure is 5.4MPaG, and the liquid hourly space velocity is 9.0h -1 . The ratio of the top plane diameter of the inner tapered cylinder in the reactor to the diameter of the reactor was 1.5.
TABLE 2 reaction conditions and product Properties (straight run diesel feedstock)
TABLE 3 reaction conditions and product Properties (catalytic Diesel feedstock)
As can be seen from the hydrogenation reaction effects of the examples and the comparative examples, the hydrogenation reactor and the hydrogenation method can realize rapid reaction at low and medium temperature sections, inhibit side reaction at high temperature section, and improve hydrogenation reaction rate and reaction depth. The method is mainly characterized in that the characteristic that the sectional area of a conical structure in the reactor is gradually reduced from bottom to top is utilized, the contact time of the raw material and the catalyst is controlled to be gradually shortened along with the rise of the reaction temperature, the coking on the surface of the catalyst is slowed down or controlled while the high-activity catalyst shows higher reaction rate, the flowing mode of the material in an annular space is from top to bottom, the characteristic that the sectional area of the annular space is gradually reduced from top to bottom is utilized, the contact time of the raw material and the catalyst is controlled to be gradually shortened when the temperature at the later stage of reaction is higher, the high-temperature coking on the surface of the catalyst can be further inhibited and slowed down or controlled during the reaction on the surface of the catalyst with slightly lower activity, and side reactions are reduced; the hydrogen is supplemented through the hydrogen supplementing component in the reaction process of the conical inner barrel, when the high consumption hydrogen in the reaction process is reached, the high dispersion hydrogen is timely supplemented, the driving force in the hydrogenation reaction process is increased, the medium and low temperature hydrogenation reaction rates are further improved, the hydrogen is supplemented through the hydrogen supplementing component in the annular space, the effects of hydrogen supplementation and steam stripping are achieved, reaction gas for inhibiting the hydrogenation reaction is stripped, and the deep hydrogenation reaction is achieved.