Liquid phase hydrogenation device, system device and method for synergistically enhancing mass transfer and reaction

Abstract

The invention discloses a liquid-phase hydrogenation device, system device and method for synergistically enhancing mass transfer and reaction. The liquid-phase hydrogenation device comprises a microbubble generator and a hydrogenation reactor, the microbubble generator comprises a liquid inlet, a gas inlet and a bubble outlet; a liquid flow meter is arranged at the liquid inlet, and a gas flow meter is arranged at the gas inlet; a bubble outlet of the microbubble generator is directly connected with an inlet end of the hydrogenation reactor through a flange; the internal structure of the hydrogenation reactor sequentially comprises a hydrogenation reactor inlet end, a first-section bed layer, a heat exchanger between the bed layers, a second-section bed layer and a hydrogenation reactor outlet end from bottom to top; a temperature measuring device, a pressure measuring device and an online monitoring device are respectively arranged; the device is systematically regulated and controlled by a mass transfer and reaction collaborative strengthening control system, and mass transfer and reaction in the liquid phase hydrogenation process can be synergistically strengthened and matched, so that the macroscopic reaction rate is maximized.

Description

Technical Field

[0001] This invention relates to the field of liquid-phase hydrogenation technology; specifically, it relates to a liquid-phase hydrogenation apparatus, system, and method for synergistically enhancing mass transfer and reaction. Background Technology

[0002] Hydrogenation is a common catalytic reaction process in modern chemical industry, widely used in petroleum refining, coal chemical industry, organic synthesis, and other fields. Taking petroleum refining as an example, hydrogenation can not only effectively remove impurities such as sulfur and nitrogen from raw materials to meet increasingly stringent environmental regulations, but also adjust the molecular structure of hydrocarbons and improve product performance. Therefore, achieving clean hydrogenation treatment of oil products has become a core link in the green transformation of refineries.

[0003] Traditional hydrogenation processes often employ trickle-bed technology, with a hydrogen circulation system to maintain hydrogen partial pressure and quench gas to control bed temperature rise. However, this process suffers from extremely high energy consumption of the hydrogen compressor and low catalyst utilization in the trickle bed. To address these issues, liquid-phase hydrogenation technology has emerged. For example, Chinese Patent Publication No. CN105647577A discloses a patented technology entitled "A Continuous Liquid-Phase Hydrocarbon Hydrogenation Process and Apparatus." This technology uses a gas-liquid mixer for premixing, allowing a hydrogen-saturated liquid stream to flow from the bottom to the top of the reactor. The final product is obtained from the reaction effluent. This method reduces the footprint and construction costs by eliminating the hydrogen circulation system. Furthermore, the continuous liquid phase in the reactor not only improves catalyst utilization efficiency but also facilitates reactor temperature control. Therefore, liquid-phase hydrogenation technology has extremely broad application prospects.

[0004] Hydrogenation reactions are often limited by mass transfer rates; therefore, finding suitable process intensification methods for liquid-phase hydrogenation is of great significance. Chinese Patent Publication No. CN105441125A discloses a patented technical solution entitled "A Method for Enhancing the Mixing Degree of Feed Oil and New Hydrogen in a Liquid-Phase Hydrorefining Unit for Oil Products." This solution utilizes a jet pump to achieve strong turbulent mixing of feed oil and new hydrogen, uniformly dispersing the new hydrogen in the feed oil to enhance the gas-liquid mass transfer process. However, this method has two significant drawbacks: first, using a jet pump to achieve strong turbulent mixing cannot dynamically adjust the bubble size at the reactor inlet according to the required hydrogenation depth, thus failing to adequately enhance mass transfer; second, as the reaction proceeds, the content of the target hydrogenated groups and the hydrogen partial pressure in the bed gradually decrease, leading to a shift from mass transfer control to reaction control, making it impossible to simultaneously intensify the reaction control section. Therefore, developing a liquid-phase hydrogenation device, system, and method that can synergistically enhance mass transfer and reaction has significant practical significance and industrial application value. Summary of the Invention

[0005] The first technical problem to be solved by the present invention is to provide a liquid-phase hydrogenation device that synergistically enhances mass transfer and reaction.

[0006] The second technical problem to be solved by the present invention is to provide a system device including the above-mentioned liquid-phase hydrogenation device with synergistic enhancement of mass transfer and reaction.

[0007] The third technical problem to be solved by the present invention is to provide a liquid-phase hydrogenation method that utilizes the above-mentioned system device to achieve synergistic enhancement of mass transfer and reaction.

[0008] To solve the first technical problem mentioned above, the present invention adopts the following technical solution:

[0009] A liquid-phase hydrogenation device that can synergistically enhance mass transfer and reaction includes a microbubble generator and a hydrogenation reactor;

[0010] The microbubble generator includes a liquid inlet, a gas inlet, and a bubble outlet; the liquid inlet is equipped with a liquid flow meter, and the gas inlet is equipped with a gas flow meter.

[0011] The bubble outlet of the microbubble generator is directly connected to the inlet of the hydrogenation reactor via a flange.

[0012] The internal structure of the hydrogenation reactor, from bottom to top, consists of the hydrogenation reactor inlet, the first bed, the interbed heat exchanger, the second bed, and the hydrogenation reactor outlet.

[0013] Temperature measuring devices, pressure measuring devices, and online monitoring devices for measuring the content of target hydrogenated groups and hydrogen partial pressure are respectively installed at three locations: the inlet end of the hydrogenation reactor, the bed layer, and the outlet end of the hydrogenation reactor.

[0014] Preferably, the microbubble generator is one of a Venturi microbubble generator, a jet flow bubble generator, a porous membrane bubble generator, and a supergravity microbubble generator.

[0015] Preferably, the liquid-phase hydrogenation device further includes a mass transfer and reaction synergistic enhancement control system for system regulation, which includes a data acquisition subsystem, a model calculation subsystem, and a parameter regulation subsystem.

[0016] Specifically, the data acquisition subsystem is used to acquire the feed liquid flow rate, feed hydrogen flow rate, and temperature, pressure, target hydrogenation group content, and hydrogen partial pressure at three locations: the inlet of the hydrogenation reactor, the bed between layers, and the outlet of the hydrogenation reactor.

[0017] Specifically, the model calculation subsystem first determines the average intrinsic reaction rate of the first bed layer and calculates the Sotter average diameter of the inlet bubbles of the first bed layer required to match the average mass transfer rate; then it determines the average mass transfer rate of the second bed layer and calculates the inlet temperature of the second bed layer required to match the average intrinsic reaction rate; finally, it limits the abrupt changes in the macroscopic reaction rate between the bed layers through the hot spot determination system to prevent the hot spot temperature from exceeding the limit range of the equipment design.

[0018] Specifically, the parameter control subsystem includes a first-stage bed inlet bubble size control device and a second-stage bed inlet temperature control device; the former adjusts the microbubble generator according to mass transfer requirements, and the latter adjusts the interbed heat exchanger according to intrinsic reaction requirements while limiting the hot spot temperature of the hydrogenation reactor.

[0019] Preferably, when the microbubble generator is a supergravity microbubble generator, the first-stage bed inlet bubble size control device dynamically controls the motor speed; the second-stage bed inlet temperature control device dynamically controls the flow rate of the heat transfer oil in the interbed heat exchanger.

[0020] To solve the second technical problem mentioned above, the present invention adopts the following technical solution:

[0021] A system apparatus including the above-mentioned synergistic enhancement of mass transfer and reaction liquid phase hydrogenation device includes a liquid phase feedstock conveying device, a hydrogen conveying device, a liquid phase hydrogenation device, and a separation and impurity removal device.

[0022] The liquid raw material conveying device includes a liquid raw material storage tank, a liquid raw material conveying pump, a liquid raw material control valve, and a liquid raw material flow meter;

[0023] The hydrogen delivery device includes a hydrogen storage tank, a hydrogen pressure reducing valve, a hydrogen control valve, and a hydrogen flow meter.

[0024] The liquid-phase hydrogenation device includes a microbubble generator and a hydrogenation reactor, and the liquid inlet of the microbubble generator is connected to a preheating device.

[0025] The separation and impurity removal device includes a separation device, a product storage tank, and a waste gas treatment device;

[0026] The liquid raw material storage tank, liquid raw material transfer pump, liquid raw material control valve, liquid raw material flow meter, and preheating device are connected in sequence via pipelines; the hydrogen storage tank, hydrogen pressure reducing valve, hydrogen control valve, hydrogen flow meter, and microbubble generator are connected in sequence via pipelines; the top outlet of the hydrogenation reactor is connected to the separation device; the liquid outlet of the separation device is connected to the product storage tank, and its gas outlet is connected to the waste gas treatment device.

[0027] Preferably, the preheating device is one or a combination of tubular furnace, thermal oil heat exchanger and high-pressure steam heat exchanger;

[0028] More preferably, the tubular furnace employs a feedforward-feedback control system for temperature regulation, placing the temperature measurement point of the feedback signal after the microbubble generator.

[0029] To solve the third technical problem mentioned above, the present invention adopts the following technical solution:

[0030] A liquid-phase hydrogenation method utilizing the above-mentioned system for synergistic enhancement of mass transfer and reaction includes the following steps:

[0031] S1. The pretreated liquid feedstock and hydrogen feedstock, which have reached the reaction pressure, enter the liquid phase hydrogenation unit under the regulation of the flow control system. After preheating, the liquid feedstock and hydrogen feedstock are premixed in a microbubble generator. The preheating temperature is controlled by the bubble outlet temperature of the microbubble generator.

[0032] S2. The bubble outlet of the microbubble generator is directly connected to the inlet of the hydrogenation reactor. The liquid feedstock carries H2 microbubbles into the first bed and undergoes a hydrogenation reaction under the action of the catalyst. The product from the outlet of the first bed is heated by the interbed heat exchanger and then enters the second bed to continue the reaction. An over-temperature interlock device is set for the outlet temperature of the hydrogenation reactor to strictly control the interbed heat exchanger to avoid over-temperature.

[0033] S3. As the reaction proceeds within the hydrogenation reactor, the content of the target hydrogenated groups and the partial pressure of hydrogen gradually decrease with increasing bed height, causing the intrinsic reaction rate of the hydrogenation reaction to gradually decrease, resulting in a transition from the mass transfer control section (first bed section) to the reaction control section (second bed section). To improve the macroscopic reaction rate within the hydrogenation reactor, a mass transfer and reaction synergistic enhancement control system is needed to systematically regulate the liquid-phase hydrogenation device. For the mass transfer control section, the feed liquid flow rate, feed hydrogen flow rate, and the temperature, pressure, target hydrogenated group content, and partial pressure at the inlet and outlet of the first bed section are first input through the data acquisition subsystem. Then, the model calculation subsystem determines the average intrinsic reaction rate of this bed section, and finally, the matching average mass transfer rate is calculated. The required Souter mean diameter of the bubble at the bed inlet for the mass transfer rate is determined. For the reaction control section, the feed liquid flow rate, feed hydrogen flow rate, and the temperature, pressure, target hydrogenation group content, and hydrogen partial pressure at the inlet and outlet of the second-stage bed are first input through the data acquisition subsystem. Then, the average mass transfer rate of this bed section is determined by the model calculation subsystem. Finally, the bed inlet temperature required to match the average intrinsic reaction rate is calculated. The hot spot determination system limits the abrupt changes in the macroscopic reaction rate between the beds to prevent the hot spot temperature from exceeding the limits of the equipment design. Based on this, the parameter control subsystem outputs from the bubble size control device at the inlet of the first-stage bed to the microbubble generator, and from the temperature control device at the inlet of the second-stage bed to the heat exchanger between the beds.

[0034] S4. The reaction product enters the separation device for purification and impurity removal; the product is collected from its liquid outlet to the product storage tank, and the separated impurities and a small amount of remaining H2 are discharged from its gas outlet and sent to the tail gas treatment device.

[0035] Preferably, in step S1, the preheating involves heating the liquid raw material to the reaction temperature; the microbubble generator is a supergravity microbubble generator used for premixing the liquid raw material and the hydrogen raw material.

[0036] More preferably, the operating temperature in the rotor region of the supergravity microbubble generator is 100–800℃ and the operating pressure is 1–30MPa; the rotational speed of the supergravity microbubble generator is 200–1500 r / min.

[0037] Preferably, in step S2, the operating temperature of the hydrogenation reactor is 100–800°C and the operating pressure is 1–30 MPa.

[0038] Preferably, in step S3, the target hydrogenation group is the corresponding group of the liquid phase hydrogenation product index, including but not limited to one or more of sulfur-containing groups, nitrogen-containing groups, oxygen-containing groups, unsaturated bonds, and aryl rings; in step S4, the separation device should be designed in conjunction with the specific hydrogenation task, including but not limited to one or more of heat exchangers, pressure reducing valves, gas-liquid separators, absorption towers, and distillation towers.

[0039] Any range described in this invention includes the endpoint, any value between the endpoints, and any subrange consisting of the endpoint or any value between the endpoints.

[0040] Unless otherwise specified, all raw materials used in this invention can be obtained commercially, and the equipment used in this invention can be conventional equipment in the relevant field or refer to existing technology in the relevant field.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] 1) This invention provides a liquid-phase hydrogenation device, system and method for synergistic enhancement of mass transfer and reaction. The method takes the inlet and outlet process parameters of the two bed sections as input quantities, and calculates and controls them through the mass transfer and reaction synergistic enhancement control system to achieve matching and synergistic enhancement of mass transfer and reaction in the two bed sections, which helps to alleviate the phenomenon of "uneven reaction rate" along the bed height in the fixed bed reactor.

[0043] 2) For the new process design, while completing the existing hydrogenation task, the device in this invention simultaneously enhances the mass transfer process in the mass transfer control section and the intrinsic reaction rate in the reaction control section. This not only shortens the residence time of reactants, thereby reducing the volume of the hydrogenation reactor and improving space utilization, but also improves hydrogen utilization and reduces hydrogen consumption, thereby saving raw material costs.

[0044] 3) For existing equipment, the method in this invention can increase the macroscopic reaction rate of the hydrogenation process, thereby significantly improving the hydrogenation depth and product quality. At the same time, the equipment upgrade only requires the addition of a microbubble generator, an interbed heat exchanger, and a mass transfer and reaction synergistic enhancement control system. The modular modification method has good engineering adaptability and scalability, which is convenient for industrial promotion. Attached Figure Description

[0045] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0046] Figure 1 This diagram shows a schematic of the liquid-phase hydrogenation apparatus for synergistic enhancement of mass transfer and reaction in this invention.

[0047] Figure 2 A flowchart illustrating the process of the mass transfer and reaction synergistic enhancement control system in this invention is shown.

[0048] Figure 3 This diagram illustrates the structure of the liquid-phase hydrogenation system device for synergistic enhancement of mass transfer and reaction in this invention. Detailed Implementation

[0049] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments and accompanying drawings, further explains the invention. Similar components in the drawings are indicated by the same reference numerals. Those skilled in the art should understand that the specific description below is illustrative rather than restrictive and should not be construed as limiting the scope of protection of the present invention.

[0050] For ease of description, the terms "first," "second," etc., used in this invention are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Furthermore, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of a person skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, such a combination should be considered non-existent and not within the scope of protection claimed by this invention.

[0051] See Figure 1 As shown, as one aspect of the present invention, a liquid-phase hydrogenation device 300 that can synergistically enhance mass transfer and reaction includes a microbubble generator 302 and a hydrogenation reactor 303.

[0052] The microbubble generator 302 includes a liquid inlet 1, a gas inlet 3, and a bubble outlet 4; the liquid inlet 1 is equipped with a liquid flow meter 19, and the gas inlet 3 is equipped with a gas flow meter 2;

[0053] The bubble outlet 4 of the microbubble generator is directly connected to the inlet 18 of the hydrogenation reactor via a flange, which can effectively prevent excessive bubble aggregation in the pipeline and reduce the mass transfer rate.

[0054] The internal structure of the hydrogenation reactor 303, from bottom to top, consists of the hydrogenation reactor inlet 18, the first bed 15, the interbed heat exchanger 14, the second bed 11, and the hydrogenation reactor outlet 8.

[0055] Temperature measuring devices (9, 12, 16), pressure measuring devices (10, 13, 17), and online monitoring devices (5, 6, 7) for measuring the content of target hydrogenated groups and hydrogen partial pressure are respectively installed at three locations: the inlet end 18 of the hydrogenation reactor, the bed between the layers, and the outlet end 8 of the hydrogenation reactor.

[0056] According to certain embodiments of the present invention, the microbubble generator 302 is one of a Venturi microbubble generator, a jet flow bubble generator, a porous membrane bubble generator, and a supergravity microbubble generator.

[0057] See Figure 2 As shown, according to some embodiments of the present invention, the liquid phase hydrogenation device 300 further includes a mass transfer and reaction synergistic enhancement control system for system regulation, the mass transfer and reaction synergistic enhancement control system including a data acquisition subsystem 20, a model calculation subsystem 21 and a parameter regulation subsystem 22;

[0058] See Figure 2 As shown, the data acquisition subsystem 20 is used to acquire the raw material liquid flow rate at the liquid inlet 1 of the microbubble generator, the raw material hydrogen flow rate at the gas inlet 3 of the microbubble generator, and the temperature, pressure, target hydrogenation group content, and hydrogen partial pressure at the inlet 18, bed interlayer, and outlet 8 of the hydrogenation reactor.

[0059] See Figure 2 As shown, the model calculation subsystem 21 first determines the average intrinsic reaction rate of the first bed layer 15 and calculates the Sotter average diameter of the inlet bubbles of the first bed layer 15 required to match the average mass transfer rate; then it determines the average mass transfer rate of the second bed layer 11 and calculates the inlet temperature of the second bed layer 11 required to match the average intrinsic reaction rate; finally, it limits the abrupt changes in the macroscopic reaction rate between the bed layers through the hot spot determination system to prevent the hot spot temperature from exceeding the limit range of the equipment design.

[0060] See Figure 2 As shown, the parameter control subsystem 22 includes a first-stage bed inlet bubble size control device and a second-stage bed inlet temperature control device; the former adjusts the microbubble generator 302 according to mass transfer requirements, and the latter adjusts the interbed heat exchanger 14 according to intrinsic reaction requirements while limiting the hot spot temperature of the hydrogenation reactor 303.

[0061] According to certain embodiments of the present invention, when the microbubble generator 302 is a supergravity microbubble generator, the first section bed inlet bubble size control device dynamically controls the motor speed; the second section bed inlet temperature control device dynamically controls the heat transfer oil flow rate of the interbed heat exchanger 14.

[0062] See Figure 1 and Figure 3 As shown, as a second aspect of the present invention, the present invention provides a system apparatus including the above-described liquid phase hydrogenation apparatus for synergistic enhancement of mass transfer and reaction, including a liquid phase feedstock conveying device 100, a hydrogen conveying device 200, a liquid phase hydrogenation apparatus 300, and a separation and impurity removal device 400.

[0063] The liquid raw material conveying device 100 includes a liquid raw material storage tank 101, a liquid raw material conveying pump 102, a liquid raw material control valve 103, and a liquid raw material flow meter 104; wherein, the liquid raw material conveying pump 102 pressurizes the liquid raw material to the pressure required for the reaction, the liquid raw material control valve 103 is used to regulate the liquid raw material feed rate, and the liquid raw material flow meter 104 is used for accurate measurement of the liquid flow rate of the raw material;

[0064] The hydrogen delivery device 200 includes a hydrogen storage tank 201, a hydrogen pressure reducing valve 202, a hydrogen control valve 203, and a hydrogen flow meter 204; wherein, the hydrogen pressure reducing valve 202 reduces the pressure of the hydrogen feedstock to the pressure required for the reaction, the hydrogen control valve 203 is used to dynamically adjust the feed gas-liquid ratio in conjunction with the liquid phase feedstock control valve 103, and the hydrogen flow meter 204 is used for accurate measurement of the hydrogen flow rate;

[0065] The liquid-phase hydrogenation device 300 includes a microbubble generator 302 and a hydrogenation reactor 303, and the liquid inlet 1 of the microbubble generator is connected to a preheating device 301; wherein, the preheating device 301 is designed to provide the energy required for the reaction of the raw materials, and the microbubble generator 302 can disperse H2 into microbubbles. The larger effective interface area and the internal and external pressure difference help to enhance the gas-liquid mass transfer process, thereby increasing the macroscopic reaction rate of the hydrogenation reaction in the hydrogenation reactor 303;

[0066] The separation and impurity removal device 400 includes a separation device 401, a product storage tank 402, and a waste gas treatment device 403; wherein, the separation device 401 purifies and removes impurities from the product of the hydrogenation reactor 303 according to the specific hydrogenation task.

[0067] The liquid raw material storage tank 101, liquid raw material transfer pump 102, liquid raw material control valve 103, liquid raw material flow meter 104, and preheating device 301 are connected in sequence via pipelines; the hydrogen storage tank 201, hydrogen pressure reducing valve 202, hydrogen control valve 203, hydrogen flow meter 204, and microbubble generator 302 are connected in sequence via pipelines; the outlet 8 of the hydrogenation reactor is connected to the separation device 401; the liquid outlet of the separation device 401 is connected to the product storage tank 402, and its gas outlet is connected to the waste gas treatment device 403.

[0068] According to certain embodiments of the present invention, the preheating device 301 is one or a combination of tubular furnace, thermal oil heat exchanger and high-pressure steam heat exchanger;

[0069] According to certain embodiments of the present invention, the tubular heater adopts a feedforward-feedback control system for temperature regulation, and the temperature measurement point of the feedback signal is placed after the microbubble generator 302; the design concept of "preheating before premixing" can effectively avoid the decrease in mass transfer rate caused by excessive aggregation of microbubbles before entering the hydrogenation reactor 303.

[0070] As a third aspect of the present invention, a liquid-phase hydrogenation method utilizing the above-described system apparatus for synergistic enhancement of mass transfer and reaction includes the following steps:

[0071] S1. The pretreated liquid feedstock and hydrogen feedstock, which have reached the reaction pressure, enter the liquid phase hydrogenation unit under the regulation of the flow control system (including liquid feedstock control valve 103, liquid feedstock flow meter 104, hydrogen control valve 203 and hydrogen flow meter 204). After being preheated by the preheating device 301, the liquid feedstock is premixed with the hydrogen feedstock in the microbubble generator 302. The preheating temperature is controlled by the temperature of the bubble outlet 4 of the microbubble generator.

[0072] S2. The bubble outlet 4 of the microbubble generator is directly connected to the inlet 18 of the hydrogenation reactor via a flange. The liquid raw material carries H2 microbubbles into the first bed 15, where a hydrogenation reaction occurs under the action of a catalyst. The product from the outlet of the first bed 15 is heated by the interbed heat exchanger 14 and then enters the second bed 11 to continue the reaction. An over-temperature interlock device is set for the temperature at the outlet 8 of the hydrogenation reactor to strictly control the interbed heat exchanger 14 to avoid over-temperature.

[0073] S3. As the reaction proceeds within the hydrogenation reactor 303, the content of the target hydrogenated groups and the partial pressure of hydrogen gradually decrease with increasing bed height, causing the intrinsic reaction rate of the hydrogenation reaction to gradually decrease, resulting in a transition from the mass transfer control section (i.e., the first bed 15) to the reaction control section (i.e., the second bed 11). To improve the macroscopic reaction rate within the hydrogenation reactor 303, it is necessary to systematically regulate the liquid-phase hydrogenation device 300 through a mass transfer and reaction synergistic enhancement control system.

[0074] First, the data acquisition subsystem 20 inputs the raw material liquid flow rate, the raw material hydrogen flow rate, and the temperature, pressure, target hydrogenation group content, and hydrogen partial pressure at three locations: the inlet 18 of the hydrogenation reactor, the bed between the layers, and the outlet 8 of the hydrogenation reactor.

[0075] Next, the model calculation subsystem 21 calculates the Sotter average diameter of the inlet bubbles in the first bed 15 and the inlet temperature of the second bed 11 required to achieve mass transfer and reaction matching.

[0076] Specifically, for the mass transfer control section (first bed 15), the temperature and pressure data at the inlet and outlet of the first bed 15 are first averaged, and the reaction rate constant k is determined in combination with the physical property parameters. AAt the same time, the content of the target hydrogenated groups C A and hydrogen partial pressure Substitute the average value into equation (1) to calculate the average intrinsic reaction rate of the first bed layer 15. Considering that the mass transfer resistance of sparingly soluble gases is concentrated in the liquid film, the average mass transfer rate of H2 within the first bed section 15 is... The specific hydrogenation task and the average intrinsic reaction rate should be considered. To achieve matching, the specific surface area a required for mass transfer and reaction matching can be obtained from equation (2); then, by substituting the inlet and outlet pressure data of the first bed 15 into equation (3), the average gas holdup in the first bed 15 can be calculated. Furthermore, based on equation (4), the average Souter average diameter of bubbles at different heights within the first bed section 15 can be determined. Finally, the empirical correlation derived from equation (5) shows the relationship between the Sotter average diameters at the inlet and outlet positions of the bed. Combining equation (6) with the specific microbubble generator 302, the Sotter average diameter (d) of the first-stage bed 15 inlet bubble required to achieve mass transfer and reaction matching can be determined. 32 ) in ;

[0077] Specifically, for the reaction control section (second bed 11), the Souter mean diameter (d) of the inlet bubble in the second bed 11 is first determined by the empirical correlation derived from equation (5) combined with physical property parameters. 32 ) in (Ignoring bubble coalescence between bed layers); then, following a similar approach, the average hydrogen mass transfer rate within the second bed layer 11 can be calculated using equations (2) to (4) and (6) in conjunction with the specific microbubble generator 302. Average intrinsic reaction rate The specific hydrogenation task and the average hydrogen mass transfer rate should be considered. To achieve matching, the process parameter data at the inlet and outlet of the second bed 11 are averaged, and then the physical property parameters are substituted into equation (1) to obtain the required reaction rate constant k. A To further determine the inlet temperature of the second bed layer 11;

[0078] Finally, the hot spot determination system limits the abrupt change in the macroscopic reaction rate of the hydrogenation reaction between the beds to prevent the hot spot temperature from exceeding the limit range of the equipment design. On this basis, the output of the first bed inlet bubble size control device of the parameter control subsystem 22 is sent to the microbubble generator 302, and the output of the second bed inlet temperature control device of the parameter control subsystem 22 is sent to the interbed heat exchanger 14.

[0079]

[0080]

[0081] Where: n1 and n2 are the reaction orders, H is the Henry's coefficient, and K... HA C is the equilibrium constant for the reaction. HA k is the concentration of the hydrogenation product of the target hydrogenation group. L C is the liquid phase mass transfer coefficient. HS Where ρ is the hydrogen saturation concentration, z is the bed height, and ρ is the saturation concentration. L ρ is the density of the liquid phase. G For gas phase density, (d 32 ) in The Souter average diameter of the bubbles at the bed inlet, (d 32 ) out u is the Souter average diameter of the bubbles at the bed outlet. L For apparent liquid velocity, u G For apparent gas velocity, μ L The viscosity of the liquid phase is μ. G Where d is the gas phase viscosity. p ε is the diameter of the bed particles. b The porosity of the bed;

[0082] S4. The reaction product at the outlet 8 of the hydrogenation reactor enters the separation unit 401 for purification and impurity removal; the product is collected into the product storage tank 402, and the separated impurities and a small amount of remaining H2 are discharged into the tail gas treatment unit 403.

[0083] According to certain embodiments of the present invention, in step S1, the preheating involves heating the liquid raw material to the reaction temperature; the microbubble generator 302 is a supergravity microbubble generator used for premixing the liquid raw material and the hydrogen raw material; the operating temperature in the rotor region of the supergravity microbubble generator is 100–800°C, and the operating pressure is 1–30 MPa; the rotational speed of the supergravity microbubble generator is 200–1500 r / min.

[0084] According to certain embodiments of the present invention, in step S2, the operating temperature of the hydrogenation reactor 303 is 100-800°C and the operating pressure is 1-30 MPa.

[0085] According to certain embodiments of the present invention, in step S3, the target hydrogenation group is the corresponding group of the liquid phase hydrogenation product index, including but not limited to one or more of sulfur-containing groups, nitrogen-containing groups, oxygen-containing groups, unsaturated bonds, and aryl rings; in step S4, the separation device 401 should be designed in conjunction with the specific hydrogenation task, including but not limited to one or more of heat exchangers, pressure reducing valves, gas-liquid separators, absorption towers, and distillation towers.

[0086] Example 1

[0087] Utilize Figure 3 The liquid-phase hydrogenation system shown here synergistically enhances mass transfer and reaction, and hydrorefines a mixture of straight-run diesel produced by an atmospheric and vacuum distillation unit and catalytic diesel produced by a catalytic cracking unit, achieving simultaneous denitrification while realizing ultra-deep desulfurization. The system includes the following steps:

[0088] S1. The feedstock diesel with a sulfur content of 4529.5 ppm and a nitrogen content of 235.0 ppm and 99.50 vol% first-grade hydrogen are pretreated and the pressure is adjusted to 6.5 MPa. Under the control of the flow control system, the feedstock diesel enters the system at a hydrogen-to-oil ratio of 100:1. The feedstock diesel is preheated to 350°C in a tubular heater and then premixed with the feedstock hydrogen in a high-gravity microbubble generator.

[0089] S2. The feed oil carrying H2 microbubbles directly enters the hydrogenation reactor from the supergravity microbubble generator. The reaction pressure is 6.5 MPa. The inlet temperature of the first bed is 340℃ and the outlet temperature is 345℃. After being heated to 365℃ by the interbed heat exchanger, it enters the second bed for reaction.

[0090] S3. As the reactions of HDS and HDN proceed within the hydrogenation reactor, the sulfur content, nitrogen content, and hydrogen partial pressure gradually decrease with increasing bed height, causing the intrinsic reaction rate of the hydrogenation reaction to gradually decrease, resulting in a transition from the mass transfer control section (first bed layer) to the reaction control section (second bed layer). To improve the macroscopic reaction rate within the hydrogenation reactor, it is necessary to systematically regulate the liquid-phase hydrogenation unit through a mass transfer and reaction synergistic enhancement control system.

[0091] First, the feedstock oil flow rate, feedstock hydrogen flow rate, and a total of 17 process parameters, including temperature, pressure, sulfur content, nitrogen content, and hydrogen partial pressure at three locations—the inlet of the hydrotreating reactor, the bed between the layers, and the outlet of the hydrotreating reactor—are input through the data acquisition subsystem.

[0092] Next, the model calculation subsystem calculates the Souter mean diameter of the first bed inlet bubble and the second bed inlet temperature required to achieve mass transfer and reaction matching.

[0093] Specifically, for the mass transfer control section, the temperature and pressure data at the inlet and outlet of the first section of the bed are averaged first, and the reaction rate constant k is determined in combination with physical property parameters. S At the same time, the sulfur content C S and hydrogen partial pressure Substitute the average value into equation (1) to calculate the average intrinsic reaction rate of the first bed section. Considering that the mass transfer resistance of sparingly soluble gases is concentrated in the liquid film, the average mass transfer rate of hydrogen in the first bed section is... It should be related to the average intrinsic reaction rate Equal to the given values, the specific surface area a required for mass transfer and reaction matching can be obtained from equation (2); then, by substituting the inlet and outlet pressure data of the first bed section into equation (3), the average gas holdup in the first bed section can be calculated. The value is 11.3%; further, according to equation (4), the average Souter average diameter of bubbles at different heights in the first bed section can be determined. The value is 327 μm; finally, the empirical correlation derived from equation (5) and equations (6) to (9) are combined, where equations (7) to (9) are used to pass through d 32 Calculate the required rotational speed N of the hypergravity microbubble generator (where ε is the energy dissipation rate, which needs to be determined in conjunction with the structural parameters of the hypergravity microbubble generator and the rotational speed N). Substituting the feed oil flow rate and feed hydrogen flow rate, the required Souter average diameter (d) of the first-stage bed inlet bubbles can be obtained. 32 ) in The value is 250 μm, corresponding to a rotational speed N of 855 r / min for the supergravity microbubble generator;

[0094] Specifically, for the reaction control section, the Souter mean diameter of the bubbles at the inlet of the second bed is first determined to be 404 μm using the empirical correlation derived from equation (5) combined with physical property parameters (ignoring bubble coalescence between beds); then, in a similar manner, the average hydrogen mass transfer rate in the second bed can be calculated using equations (2) to (4) and (6) to (9); the average intrinsic reaction rate should match the average hydrogen mass transfer rate. After averaging the process parameter data at the inlet and outlet of the second bed, the required reaction rate constant k can be obtained by substituting the physical property parameters into equation (1). S The inlet temperature of the second bed layer was further determined to be 365℃;

[0095] Finally, the hot spot temperature is controlled below 375℃ under the limitation of the sudden change value of the macroscopic reaction rate between the bed layers by the hot spot determination system; on this basis, the motor frequency of the ultragravity microbubble generator is dynamically adjusted by the first bed inlet bubble size control device of the parameter control subsystem, and the heat transfer oil flow rate of the heat exchanger between the bed layers is dynamically adjusted by the second bed inlet temperature control device of the parameter control subsystem.

[0096]

[0097] d min =11.4(μ) L / ρ L ) 3 / 4 ε -1 / 4 Equation (8)

[0098] d max =ε -2 / 5 (σ L We c / 2ρL ) 3 / 5 Equation (9)

[0099] Where: d min d is the minimum bubble diameter. max For the maximum bubble diameter, σ L For the surface tension of the liquid phase, We c The critical Weber number;

[0100] S4. The reaction products enter the separation unit for purification and impurity removal; the hydrogenated diesel product has a sulfur content of 7.4 ppm and a nitrogen content of 3.6 ppm, with a desulfurization rate of 99.8 w% and a denitrification rate of 98.4 w%; the tail gas enriched with impurities such as H2S and NH3 and a small amount of residual H2 is discharged into the tail gas treatment unit.

[0101] Comparative Example 1

[0102] Repeat Example 1, but remove the interbed heat exchanger and the mass transfer and reaction synergistic enhancement control system from the original device.

[0103] The results showed that when the outlet temperature of the hydrotreating reactor decreased by 20℃, the hydrotreating reactions of HDS and HDN in the second bed were significantly limited by intrinsic reaction rates, and the desulfurization rate of the product diesel decreased to 97.9 wt% and the denitrification rate decreased to 96.7 wt%.

[0104] Comparative Example 2

[0105] Repeat Comparative Example 1, replacing the hypergravity microbubble generator with a static mixer in the original apparatus.

[0106] The results showed that the bubble size at the inlet of the hydrotreating reactor increased significantly, and the hydrotreating reactions of HDS and HDN in the first bed were significantly limited by the mass transfer rate. The hydrogen utilization rate decreased by 11.2% year-on-year, and the desulfurization rate of the product diesel decreased to 92.7 wt% and the denitrification rate decreased to 87.3 wt%.

[0107] Comparative Example 3

[0108] Repeat Example 1, and build new equipment based on the original hydrogenation refining goal. Replace the supergravity microbubble generator with a static mixer, and remove the interbed heat exchanger and the mass transfer and reaction synergistic enhancement control system.

[0109] The results showed that the macroscopic reaction rate in the hydrotreating reactor was significantly reduced, which led to a substantial increase in the residence time required for diesel and hydrogen in the hydrotreating reactor, and the volume of the hydrotreating reactor required to achieve the original hydrorefining target increased by 21.3%.

[0110] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is impossible to exhaustively list all embodiments here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A liquid-phase hydrogenation device capable of synergistically enhancing mass transfer and reaction, characterized in that, Includes microbubble generators and hydrogenation reactors; The microbubble generator includes a liquid inlet, a gas inlet, and a bubble outlet; the liquid inlet is equipped with a liquid flow meter, and the gas inlet is equipped with a gas flow meter. The bubble outlet of the microbubble generator is directly connected to the inlet of the hydrogenation reactor via a flange. The internal structure of the hydrogenation reactor, from bottom to top, consists of the hydrogenation reactor inlet, the first bed, the interbed heat exchanger, the second bed, and the hydrogenation reactor outlet. Temperature measuring devices, pressure measuring devices, and online monitoring devices for measuring the content of target hydrogenated groups and hydrogen partial pressure are respectively installed at three locations: the inlet end of the hydrogenation reactor, the bed layer, and the outlet end of the hydrogenation reactor.

2. The liquid-phase hydrogenation apparatus according to claim 1, characterized in that: The microbubble generator is one of the following: Venturi microbubble generator, jet flow bubble generator, porous membrane bubble generator, and supergravity microbubble generator.

3. The liquid-phase hydrogenation apparatus according to claim 1, characterized in that: The liquid-phase hydrogenation device also includes a mass transfer and reaction synergistic enhancement control system for its system regulation. The mass transfer and reaction synergistic enhancement control system includes a data acquisition subsystem, a model calculation subsystem, and a parameter regulation subsystem. The data acquisition subsystem is used to acquire the feed liquid flow rate, feed hydrogen flow rate, and temperature, pressure, target hydrogenation group content, and hydrogen partial pressure at three locations: the inlet end of the hydrogenation reactor, the bed layer, and the outlet end of the hydrogenation reactor. The model calculation subsystem first determines the average intrinsic reaction rate of the first bed layer and calculates the Sotter average diameter of the inlet bubbles of the first bed layer required to match the average mass transfer rate; then it determines the average mass transfer rate of the second bed layer and calculates the inlet temperature of the second bed layer required to match the average intrinsic reaction rate; finally, it limits the abrupt changes in the macroscopic reaction rate between the bed layers through the hot spot determination system to prevent the hot spot temperature from exceeding the limit range of the equipment design. The parameter control subsystem includes a first-stage bed inlet bubble size control device and a second-stage bed inlet temperature control device; the former adjusts the microbubble generator according to mass transfer requirements, and the latter adjusts the interbed heat exchanger according to intrinsic reaction requirements while limiting the hot spot temperature of the hydrogenation reactor.

4. The liquid-phase hydrogenation apparatus according to claim 3, characterized in that: When the microbubble generator is a supergravity microbubble generator, the first-stage bed inlet bubble size control device dynamically controls the motor speed; the second-stage bed inlet temperature control device dynamically controls the flow rate of heat transfer oil in the interbed heat exchanger.

5. A system apparatus comprising a liquid-phase hydrogenation device for synergistic enhancement of mass transfer and reaction as described in any one of claims 1-4, characterized in that, It includes a liquid-phase feedstock conveying device, a hydrogen conveying device, a liquid-phase hydrogenation device, and a separation and impurity removal device; The liquid raw material conveying device includes a liquid raw material storage tank, a liquid raw material conveying pump, a liquid raw material control valve, and a liquid raw material flow meter; The hydrogen delivery device includes a hydrogen storage tank, a hydrogen pressure reducing valve, a hydrogen control valve, and a hydrogen flow meter. The liquid-phase hydrogenation device includes a microbubble generator and a hydrogenation reactor, and the liquid inlet of the microbubble generator is connected to a preheating device. The separation and impurity removal device includes a separation device, a product storage tank, and a waste gas treatment device; The liquid raw material storage tank, liquid raw material transfer pump, liquid raw material control valve, liquid raw material flow meter, and preheating device are connected in sequence via pipelines; the hydrogen storage tank, hydrogen pressure reducing valve, hydrogen control valve, hydrogen flow meter, and microbubble generator are connected in sequence via pipelines; the top outlet of the hydrogenation reactor is connected to the separation device; the liquid outlet of the separation device is connected to the product storage tank, and its gas outlet is connected to the waste gas treatment device.

6. The system apparatus according to claim 5, characterized in that: The preheating device is one or a combination of tubular heating furnace, thermal oil heat exchanger and high-pressure steam heat exchanger. Preferably, the tubular furnace employs a feedforward-feedback control system for temperature regulation, placing the temperature measurement point of the feedback signal after the microbubble generator.

7. A liquid-phase hydrogenation method utilizing the system apparatus described in any one of claims 5-6 for synergistic enhancement of mass transfer and reaction, characterized in that, Includes the following steps: S1. The pretreated liquid feedstock and hydrogen feedstock, which have reached the reaction pressure, enter the liquid phase hydrogenation unit under the regulation of the flow control system. After preheating, the liquid feedstock and hydrogen feedstock are premixed in a microbubble generator. The preheating temperature is controlled by the bubble outlet temperature of the microbubble generator. S2. The bubble outlet of the microbubble generator is directly connected to the inlet of the hydrogenation reactor. The liquid feedstock carries H2 microbubbles into the first bed and undergoes a hydrogenation reaction under the action of the catalyst. The product from the outlet of the first bed is heated by the interbed heat exchanger and then enters the second bed to continue the reaction. An over-temperature interlock device is set for the outlet temperature of the hydrogenation reactor to strictly control the interbed heat exchanger to avoid over-temperature. S3. As the reaction proceeds within the hydrogenation reactor, the content of the target hydrogenated groups and the partial pressure of hydrogen gradually decrease with increasing bed height, causing the intrinsic reaction rate of the hydrogenation reaction to gradually decrease, resulting in a transition from the mass transfer control section (first bed section) to the reaction control section (second bed section). To improve the macroscopic reaction rate within the hydrogenation reactor, a mass transfer and reaction synergistic enhancement control system is needed to systematically regulate the liquid-phase hydrogenation device. For the mass transfer control section, the feed liquid flow rate, feed hydrogen flow rate, and the temperature, pressure, target hydrogenated group content, and partial pressure at the inlet and outlet of the first bed section are first input through the data acquisition subsystem. Then, the model calculation subsystem determines the average intrinsic reaction rate of this bed section, and finally, the matching average mass transfer rate is calculated. The required Souter mean diameter of the bubble at the bed inlet for the mass transfer rate is determined. For the reaction control section, the feed liquid flow rate, feed hydrogen flow rate, and the temperature, pressure, target hydrogenation group content, and hydrogen partial pressure at the inlet and outlet of the second-stage bed are first input through the data acquisition subsystem. Then, the average mass transfer rate of this bed section is determined by the model calculation subsystem. Finally, the bed inlet temperature required to match the average intrinsic reaction rate is calculated. The hot spot determination system limits the abrupt changes in the macroscopic reaction rate between the beds to prevent the hot spot temperature from exceeding the limits of the equipment design. Based on this, the parameter control subsystem outputs from the bubble size control device at the inlet of the first-stage bed to the microbubble generator, and from the temperature control device at the inlet of the second-stage bed to the heat exchanger between the beds. S4. The reaction product enters the separation device for purification and impurity removal; the product is collected from its liquid outlet to the product storage tank, and the separated impurities and a small amount of remaining H2 are discharged from its gas outlet and sent to the tail gas treatment device.

8. The liquid-phase hydrogenation method according to claim 7, characterized in that: In step S1, the preheating involves raising the temperature of the liquid raw material to the reaction temperature; the microbubble generator is a supergravity microbubble generator used for premixing the liquid raw material and the hydrogen raw material. Preferably, the operating temperature in the rotor region of the supergravity microbubble generator is 100–800℃ and the operating pressure is 1–30MPa; the rotational speed of the supergravity microbubble generator is 200–1500 r / min.

9. The liquid-phase hydrogenation method according to claim 7, characterized in that: In step S2, the operating temperature of the hydrogenation reactor is 100–800°C, and the operating pressure is 1–30 MPa.

10. The liquid-phase hydrogenation method according to claim 7, characterized in that: In step S3, the target hydrogenation group is the corresponding group of the liquid phase hydrogenation product index, including but not limited to one or more of sulfur-containing groups, nitrogen-containing groups, oxygen-containing groups, unsaturated bonds, and aryl rings; in step S4, the separation device should be designed in conjunction with the specific hydrogenation task, including but not limited to one or more of heat exchangers, pressure reducing valves, gas-liquid separators, absorption towers, and distillation towers.

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