A cyclic amination reaction system

Abstract

This invention discloses a loop amination reaction system, belonging to the technical field of amination reaction systems. It includes a reaction vessel with a jet mixer mounted on its top. The input end of the jet mixer is connected to a heat exchanger, and the input end of the heat exchanger is connected to the bottom of the reaction vessel via a first circulation pump. It also includes a gas mixing module, a feed guiding unit, and a gas-liquid enhancement unit. The gas mixing module includes a mixing tank equipped with a dimethylamine concentration transmitter and an opening valve. The opening valve is connected to a raw material gas storage tank for a single amination reaction. The input end of the mixing tank is connected to the output end of a vacuum pump, which is connected to the upper inner side of the reaction vessel. The suction end of the jet mixer is connected to the output end of the mixing tank. This loop amination reaction system, constructed through a loop reactor, ensures reaction uniformity, guarantees sufficient gas-liquid contact, and prevents the increase of by-products.

Description

Technical Field

[0001] This invention specifically relates to a cyclic amination reaction system, belonging to the technical field of amination reaction systems. Background Technology

[0002] Amination is a reaction process in which an amino group is introduced into an organic molecule to form an amine. For example, Chinese Patent Publication No. CN115920788A discloses an amination reaction system that features good heat transfer performance, uniform and easily controllable temperature within the reactor bed, convenient continuous catalyst regeneration and recycling, high catalyst and ammonia utilization, and low ammonia consumption. Unreacted ammonia is recovered, thus enabling more efficient ammonia utilization and reducing ammonia usage. Simultaneously, inert gases are separated, recovered, and reused, further reducing energy consumption. Another example is Chinese Patent Publication No. CN214051645U, which discloses… An amination reactor is proposed. This structure ensures that all raw materials are fully utilized by controlling the amount used in advance, maintaining the stability of the entire device during operation, ensuring that the internal amination reaction can proceed normally, and improving the safety of the reactor. In the existing technology, amination reactions mostly adopt batch batch reactors. Among them, batch amination has problems such as high energy consumption, uneven reaction, and excessively high local concentration leading to an increase in by-products (such as high residual N,N-dimethylpropenylamine); batch operation cannot achieve continuous production, and the contact between gaseous raw materials (such as dimethylamine) and the liquid phase is insufficient, limiting the conversion rate. Summary of the Invention

[0003] To address the aforementioned problems, this invention proposes a loop amination reaction system. By constructing the amination reaction system through a loop reactor, the reaction uniformity and sufficient gas-liquid contact can be ensured, while preventing the increase of byproducts.

[0004] The loop amination reaction system of the present invention includes a reaction vessel, a jet mixer installed on the top of the reaction vessel, an input end of the jet mixer connected to a heat exchanger, and the input end of the heat exchanger connected to the bottom of the reaction vessel via a first circulation pump. In use, an amination reaction mixture, consisting of a substrate and a catalyst, is added to the reaction vessel. Then, the first circulation pump operates, pumping the mixture from the reaction vessel into the heat exchanger. After being heated to the reaction temperature by the heat exchanger, the mixture enters the jet mixer, which simultaneously draws in a gas (such as dimethylamine) participating in the amination reaction. After thorough mixing of the gas and liquid, the mixture is pumped back into the reaction vessel, completing one amination reaction.

[0005] Also includes:

[0006] A gas mixing module includes a mixing tank, on which a dimethylamine concentration transmitter and an opening valve are installed; the opening valve is connected to a raw material gas storage tank for a single amination reaction; the input end of the mixing tank is connected to the output end of a vacuum pump, and the input end of the vacuum pump is connected to the upper inner side of the reaction tank; the suction end of the jet mixer is connected to the output end of the mixing tank.

[0007] When the gas-liquid mixture enters the reaction tank, the unreacted gas rises to the upper part of the inner side of the reaction tank. Then, it is pumped out by the vacuum pump and sent to the mixing tank for temporary storage, waiting for the second cycle of the amination reaction. The gas is then drawn back into the jet mixer to complete the gas-liquid mixing again. In order to ensure that the gas concentration entering the jet mixer reaches the set requirements during the cycle, gas is replenished to the mixing tank through the raw material gas storage tank and the opening valve. The raw material gas storage tank stores a gas volume that matches the volume of the reaction substrate.

[0008] The material guiding unit includes a first screw cylinder fixed to the top of the inner side of the reaction tank, a guide cylinder screwed into the inner side of the first screw cylinder, and the bottom of the jet mixer fixed to the inner side of the guide cylinder.

[0009] A gas-liquid enhancement unit is slidably disposed outside a guide tube. The gas-liquid enhancement unit includes a disc base, with an orifice plate fixed to the bottom of the disc base via a support column. A gas-liquid separation unit and multiple reflux drippers are disposed on the disc base. Multiple concentric annular tubes of unequal diameter are disposed at the bottom of the orifice plate. Multiple flow guides are spaced apart on the annular tubes, with the liquid absorption surfaces of adjacent flow guides intersecting to complete the pumping of the entire liquid surface. The flow guides are fixed to the orifice plate. The bottom of the annular tubes is connected to a manifold, which communicates with a mixing pipe. The mixing pipe is fixed to the inner wall of the reaction tank via a support flange. The bottom of the mixing pipe is connected to a regulating valve outside the reaction tank. An external discharge pipe is disposed at the bottom of the reaction tank, connecting to a first circulation pump and a discharge valve. The output ends of the regulating valve and the first circulation pump are respectively connected to two input ends of a mixing unit. The output end of the mixing unit is connected to the input end of a heat exchanger.

[0010] The plate is above the liquid level in the reaction vessel, and the orifice plate is submerged in the liquid level in the reaction vessel.

[0011] The gas-liquid separation and gas-liquid enhancement units are used to extract the bubble layer fluid from the liquid surface in the reaction tank and mix it with the fluid at the bottom of the reaction tank. This increases the gas content of the fluid at the bottom of the reaction tank and dilutes the gas content at the liquid surface. Simultaneously, the fluid undergoes pre-gas-liquid mixing before entering the Venturi jet injector. The specific working process is as follows:

[0012] The solid-liquid mixture sprayed from the jet mixer is guided by the guide tube of the material guiding unit, allowing it to smoothly enter the gas-liquid enhancement unit below. In the arrangement of the gas-liquid enhancement unit, the plate base is higher than the liquid level in the reaction tank, and the orifice plate is submerged in the liquid level. The flow guide on the orifice plate draws the bubble layer at the liquid level into the ring pipe, and then out of the reaction tank through the manifold and mixing pipe. It is then fed into the mixing unit through the regulating valve. Simultaneously, the bottom drain pipe of the reaction tank enters the mixing unit through the first circulation pump, achieving liquid level... The mixture is repeatedly mixed with the two fluids at the bottom. After mixing, it enters the heat exchanger for temperature control, and then enters the jet mixer to re-inhale new gas, completing the gas-liquid mixing again. This cycle continues until the amination reaction is completed, at which point the reactants are discharged from the reaction tank through the discharge valve. After the gas-liquid mixture enters the reaction tank, it undergoes gas-liquid separation through the gas-liquid separation unit on the disc. The gas rises to the top of the reaction tank through the gas-liquid separation unit, while the liquid and some of the trapped gas are isolated below the disc and pumped into the mixing unit through the guide hood.

[0013] Furthermore, the mixing unit is a Venturi ejector; the output end of the first circulation pump is connected to the input end of the Venturi ejector, and the regulating valve is connected to the negative pressure suction end of the Venturi ejector; the fluid at the bottom of the reaction tank is pumped into the Venturi ejector at high speed by the first circulation pump, causing a negative pressure to be generated at the negative pressure end of the Venturi ejector, thereby drawing the fluid on the surface of the reaction tank into the Venturi ejector. After the two fluids are fully mixed by the Venturi ejector, they are sent to the heat exchanger; when the fluid on the surface of the reaction tank is drawn into the Venturi ejector, the flow rate can be adjusted by the regulating valve.

[0014] Furthermore, the mixing unit is a proportional valve, and the regulating valve and the output of the first circulating pump are respectively connected to the two inputs of the proportional valve; the proportional valve can mix the fluid at the liquid level of the reaction tank and the fluid at the bottom of the reaction tank, and can accurately control the mixing ratio between the two fluids, thereby completing the mixing ratio control and the full mixing of the fluids.

[0015] Furthermore, a support base for supporting the gas-liquid enhancement unit is provided outside the guide tube; the support base can limit the height position of the gas-liquid enhancement unit. When the reaction tank performs a cyclic amination reaction, the bottom material and catalyst are quantitatively added, so that the liquid surface of the reaction bottom material can enter the gas-liquid enhancement unit.

[0016] Furthermore, the mixing pipe is a telescopic pipe, and the outer pipe of the telescopic pipe is fixed to the inner wall of the reaction vessel through a supporting flange; the inner pipe of the telescopic pipe is connected to the manifold; a screw body is rotatably installed on the side of the disc base away from the telescopic pipe; a tray that movably abuts against the bottom of the disc base is embedded in the bottom of the screw body; the tray and the screw body are fastened with bolts; a second screw cylinder is rotatably passed through the top of the screw body and a crank is fixed thereon; the second screw cylinder is fixed to the top of the inner side of the reaction vessel.

[0017] To adapt to different liquid levels in the substrate, the orifice plate of the gas-liquid enhancement unit is positioned below the liquid surface, while the tray is positioned above the liquid surface. The height of the gas-liquid enhancement unit within the reaction vessel is adjusted by cranking the hand crank. During adjustment, the hand crank drives the screw body to rotate along the second screw barrel. The screw body rotates synchronously with the tray. Through the cooperation of the screw body and the second screw barrel, the rotational force is converted into a linear lifting force, driving the tray to move the tray and tray synchronously up and down. During lifting and down, the mixing pipe with the telescopic structure provides linear guidance and length self-adaptation.

[0018] Furthermore, it also includes a feeding unit, which includes a feeding hopper. The feeding hopper is connected to a feed pipe via a valve group, and the other end of the feed pipe is connected to the inside of a guide tube or the lower inner side of the reaction tank. The feeding unit feeds the reaction substrate and catalyst into the reaction tank. The feeding unit is directly located at the lower part of the reaction tank or inside the feed pipe, which allows the reaction substrate to smoothly enter the gas-liquid enhancement unit below.

[0019] Furthermore, a second circulation pump is connected in series between the jet mixer and the heat exchanger. The second circulation pump can both balance the pressure of the fluid entering the jet mixer and enhance the pressure of the fluid entering the jet mixer, thereby increasing the amount of reactive gas attracted by the jet mixer.

[0020] Furthermore, the jet mixer is externally sealed with an outer casing; the jet mixer has multiple negative pressure extraction ports on the inner side of the outer casing; the raw material gas storage tank is connected to the raw material supply pipe valve through a gas metering valve; the outer casing provides reaction gas comprehensively and evenly to the negative pressure extraction area, and the reaction gas is sent into the jet mixer through the multiple negative pressure extraction ports; this increases the mixing volume of the fluid and reaction gas; when the reaction raw material gas is supplied, the raw material supply pipe valve injects the total amount of gas from a single reaction into the raw material gas storage tank at once through the gas metering valve, and then... The set amount of working gas is injected into the mixing tank through the opening valve. After the jet mixer completes one injection mixing and reaction, the unreacted gas re-enters the mixing tank. At the same time, the concentration of the reactant gas is monitored in real time by the dimethylamine concentration transmitter. When the concentration of the reactant gas is less than the set value, even if the jet mixer injects fluid, the reactant gas entering the jet mixer cannot meet the fluid reaction requirements. In this case, the opening valve needs to respond quickly to replenish the gas, so as to avoid wasting circulation power, prolonging the loop reaction time, and large fluctuations in the concentration of reactant gas in the fluid in each cycle.

[0021] Furthermore, a sealing ring is provided on the outside of the disc base to fit against the inner wall of the reaction vessel; a gap of 1-3 cm is provided between the orifice plate and the inner wall of the reaction vessel; the sealing ring can form a gas-liquid separation space inside the reaction vessel, which can prevent the reactant gas after gas-liquid separation from re-covering the liquid interface layer; the gap between the orifice plate and the reaction vessel allows the orifice plate to easily enter the liquid surface layer, so that the top surface of the orifice plate is flush with or slightly lower than the liquid surface layer, thereby enabling it to be quickly drawn into the mixing unit at the first moment when the bubble interface is generated on the liquid surface, realizing the dilution of the bubble interface and increasing the concentration of reactant gas in the circulating fluid.

[0022] Furthermore, the jet mixer is embedded outward from the inside of the reaction vessel. An annular seat is integrally formed on the outside of the reaction vessel at the embedded end. A threaded hole is formed on the annular seat, and an annular cover is positioned directly above the annular seat. An elastic pressure ring is positioned between the annular cover and the annular seat, through which the jet mixer moves. The elastic pressure ring is fitted onto the outside of the jet mixer. The annular cover and the annular seat are fastened with bolts. During installation, the jet mixer is first fastened to the guide tube. Then, the jet mixer is embedded out from the inside of the reaction vessel, and the guide tube is screwed and fastened to the first threaded tube. Next, the elastic pressure ring and the annular cover are fitted. The annular cover is then fixed to the annular seat with a bolt. At this point, due to the compression of the elastic pressure ring by the annular cover and the annular seat, a sealed installation between the outside of the jet mixer and the reaction vessel is achieved. Finally, the outer casing and the input pipeline of the jet mixer are installed.

[0023] Compared with the prior art, the loop amination reaction system of the present invention directly draws the gas-liquid critical bubble interface layer into the mixing tube, and the mixing unit ensures that the bubble layer in the mixing tube is in full contact with the fluid at the bottom of the reaction tank. After the fluid mixed with the bubble layer passes through the external circulation channel and heat exchanger for temperature control, it can undergo a full amination reaction, improving the amination reaction effect of the fluid and preventing the liquid surface layer in the reaction tank from being in a high concentration state of reaction gas for a long time, thus reducing the production of by-products. In addition, the high concentration of reaction gas in the liquid surface layer is further controlled by the gas-liquid separation unit and the vacuum pump. The vacuum pump collects unreacted oxalic acid gas into the mixing tank, and the concentration of reaction gas in the mixing tank is controlled by the linkage of the dimethylamine concentration transmitter and the opening valve, so that the concentration and pressure of reaction gas entering the suction end of the jet mixer are in a stable state, thereby ensuring that the fluid entering the jet mixer is mixed with the reaction gas more uniformly and stably. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the cyclic amination reaction system of the present invention, which consists of a mixing unit composed of a proportional valve.

[0025] Figure 2 For the present invention Figure 1 A magnified schematic diagram of the structure at point A in the middle.

[0026] Figure 3 For the present invention Figure 1 A magnified schematic diagram of the structure at point B in the middle.

[0027] Figure 4 This is a schematic diagram of the structure of the gas-liquid enhancement unit height-adjustable cyclic amination reaction system of the present invention.

[0028] Figure 5 This is a schematic diagram of the screw body, tray, and crank assembly structure of the present invention.

[0029] Figure 6 This is a schematic diagram of the loop amination reaction system of the present invention, which consists of a mixing unit composed of a Venturi jet.

[0030] Figure 7 This is a schematic diagram of the loop amination reaction system with a second circulation pump installed in the external circulation pipeline of the present invention.

[0031] Figure 8 This is a schematic diagram of the loop amination reaction system with a feeding unit installed at the bottom of the reaction vessel according to the present invention.

[0032] Reference numerals: 1. Reaction vessel; 2. Jet mixer; 3. Heat exchanger; 4. First circulation pump; 5. Mixing vessel; 6. Dimethylamine concentration transmitter; 7. Opening valve; 8. Vacuum pump; 9. First screw; 10. Guide tube; 11. Disc seat; 12. Orifice plate; 13. Gas-liquid separation unit; 14. Return dripper; 15. Ring pipe; 16. Guide hood; 17. Mixing pipe; 18. Regulating valve; 19. External discharge pipe; 20. Discharge pipe valve; 21. Venturi jet injector; 22. Proportional valve; 23. Support body; 24. Screw body; 25. Tray; 26. Second screw; 27. Hand crank; 28. Feed hopper; 29. ​​Valve assembly; 30. Feed pipe; 31. Second circulation pump; 32. Outer cover; 33. Negative pressure suction port; 34. Ring seat; 35. Ring cover; 36. Elastic pressure ring. Detailed Implementation

[0033] Example:

[0034] like Figures 1 to 8 The illustrated amination reaction system includes a reaction vessel 1, with a jet mixer 2 mounted on top of the reaction vessel 1. The input end of the jet mixer 2 is connected to a heat exchanger 3, and the input end of the heat exchanger 3 is connected to the bottom of the reaction vessel 1 via a first circulation pump 4. In use, an amination reaction mixture, consisting of a substrate and a catalyst, is added into the reaction vessel 1. Then, the first circulation pump 4 is activated, pumping the mixture from the reaction vessel 1 into the heat exchanger 3. After being heated to the reaction temperature by the heat exchanger 3, the mixture enters the jet mixer 2. The jet mixer 2 simultaneously draws in the gas (such as dimethylamine) participating in the amination reaction. After the gas and liquid are thoroughly mixed, they are pumped back into the reaction vessel 1, completing one amination reaction.

[0035] Also includes:

[0036] A gas mixing module includes a mixing tank 5, on which a dimethylamine concentration transmitter 6 and an opening valve 7 are installed; the opening valve 7 is connected to a raw material gas storage tank for a single amination reaction; the input end of the mixing tank 5 is connected to the output end of a vacuum pump 8, and the input end of the vacuum pump 8 is connected to the upper inner side of the reaction tank 1; the suction end of the jet mixer 2 is connected to the output end of the mixing tank 5.

[0037] When the gas-liquid mixture enters the reaction tank 1, the unreacted gas floats to the upper part of the inner side of the reaction tank 1. Then, it is pumped out by the vacuum pump 8 and sent to the mixing tank 5 for temporary storage, waiting for the second amination reaction cycle to arrive. The gas is then drawn back into the jet mixer 2 to complete the gas-liquid mixing again. In order to ensure that the gas concentration entering the jet mixer 2 reaches the set requirements during the cycle, gas is supplied to the mixing tank 5 through the raw material gas storage tank and the opening valve 7. The raw material gas storage tank stores a gas volume that matches the volume of the reaction substrate.

[0038] The material guiding unit includes a first screw cylinder 9 fixed to the top of the inner side of the reaction tank 1, a guide cylinder 10 screwed to the inner side of the first screw cylinder 9, and the bottom of the jet mixer 2 fixed to the inner side of the guide cylinder 10.

[0039] A gas-liquid enhancement unit is slidably disposed outside the guide tube 10. The gas-liquid enhancement unit includes a disk base 11, with a perforated plate 12 fixed to the bottom of the disk base 11 by a support column. A gas-liquid separation unit 13 and multiple reflux drippers 14 are disposed on the disk base 11. The gas-liquid separation unit 13 is composed of an array of exhaust heads that rotate through the disk base. The exhaust head array is composed of multiple exhaust heads with internal conical through holes. Multiple concentric annular tubes 15 of unequal diameter are disposed at the bottom of the perforated plate 12. Multiple guide hoods 16 are spaced apart on the annular tubes 15, with the liquid absorption surfaces of adjacent guide hoods 16 intersecting. The entire liquid surface is pumped out; the flow guide shroud 16 is fixed to the orifice plate 12; the bottom of the ring pipe 15 is connected to the manifold, the manifold is connected to the mixing pipe 17, and the mixing pipe 17 is fixed to the inner wall of the reaction tank 1 through the support flange; the bottom of the mixing pipe 17 is connected to the regulating valve 18 outside the reaction tank 1, and the bottom of the reaction tank 1 is provided with an external discharge pipe 19, which is connected to the first circulation pump 4 and the discharge pipe valve 20 respectively; the output end of the regulating valve 18 and the first circulation pump 4 are respectively connected to the two input ends of the mixing unit; the output end of the mixing unit is connected to the input end of the heat exchanger 3;

[0040] The plate 11 is higher than the liquid level in the reaction vessel 1, and the orifice plate 12 is submerged in the liquid level in the reaction vessel 1.

[0041] The gas-liquid separation and the extraction of the bubble layer fluid from the liquid surface in reaction tank 1 through the feeding unit and the gas-liquid enhancement unit are achieved and mixed with the fluid at the bottom of reaction tank 1. This enhances the gas content of the fluid at the bottom of reaction tank 1 and dilutes the gas content at the liquid surface. Simultaneously, the fluid undergoes pre-gas-liquid mixing before entering the Venturi jet injector. The specific working process is as follows:

[0042] The solid-liquid mixture sprayed by the jet mixer 2 is guided by the guide tube 10 of the material guiding unit, allowing it to smoothly enter the gas-liquid enhancement unit below. When the gas-liquid enhancement unit is arranged, the plate 11 is higher than the liquid level in the reaction tank 1, and the orifice plate 12 is submerged in the liquid level of the reaction tank 1. The bubble layer at the liquid level is drawn into the ring pipe 15 through the guide shroud 16 on the orifice plate 12, and then discharged from the reaction tank 1 through the manifold and mixing pipe 17. It is then fed into the mixing unit through the regulating valve 18. Simultaneously, the discharge pipe 19 at the bottom of the reaction tank 1 enters the mixing unit through the first circulation pump 4. The two fluids, one at the surface and one at the bottom, are repeatedly mixed. After mixing, they enter the heat exchanger 3 for temperature control, and then enter the jet mixer 2 to draw in new gas, completing the gas-liquid mixing again. This cycle continues until the amination reaction is completed. The reaction mixture is then discharged from the reaction tank 1 through the discharge valve 20. After the gas-liquid mixture enters the reaction tank 1, it undergoes gas-liquid separation through the gas-liquid separation unit 13 on the disc 11. The gas rises to the top of the reaction tank 1 through the gas-liquid separation unit 13, while the liquid and some of the trapped gas are isolated below the disc 11. The gas-liquid mixture is then pumped into the mixing unit through the guide shroud 16.

[0043] The mixing unit is a Venturi jet injector 21; the output end of the first circulation pump 4 is connected to the input end of the Venturi jet injector 21, and the regulating valve 18 is connected to the negative pressure suction end of the Venturi jet injector 21; the fluid at the bottom of the reaction tank 1 is pumped into the Venturi jet injector 21 at high speed by the first circulation pump 4, so that the negative pressure end of the Venturi jet injector 21 generates negative pressure, thereby drawing the liquid surface fluid of the reaction tank 1 into the Venturi jet injector 21. After the two fluids are fully mixed by the Venturi jet injector 21, they are sent to the heat exchanger 3; when the liquid surface fluid of the reaction tank 1 is drawn into the Venturi jet injector 21, the flow rate can be adjusted by the regulating valve 18.

[0044] The mixing unit is a proportional valve 22, and the output of the regulating valve 18 and the first circulating pump 4 are respectively connected to the two inputs of the proportional valve 22. The proportional valve 22 can mix the fluid at the liquid surface of the reaction tank 1 and the fluid at the bottom of the reaction tank 1, and can accurately control the mixing ratio between the two fluids, so as to complete the mixing ratio control and the full mixing of the fluids.

[0045] The guide tube 10 is provided with a support base 23 for supporting the gas-liquid enhancement unit. The support base 23 can limit the height position of the gas-liquid enhancement unit. When the reaction tank 1 performs the cyclic amination reaction, the bottom material and catalyst are quantitatively added, so that the liquid surface of the reaction bottom material can enter the gas-liquid enhancement unit.

[0046] The mixing pipe 17 is a telescopic pipe, and the outer pipe of the telescopic pipe is fixed to the inner wall of the reaction vessel 1 through a supporting flange; the inner pipe of the telescopic pipe is connected to the manifold; a screw body 24 is rotatably installed on the side of the disc base 11 away from the telescopic pipe; a tray 25 is fitted into the bottom of the screw body 24 and moves against the bottom of the disc base 11; the tray 25 and the screw body 24 are fastened with bolts; the top of the screw body 24 rotates through a second screw cylinder 26 and is fixed with a crank handle 27; the second screw cylinder 26 is fixed to the top of the inner side of the reaction vessel 1.

[0047] To adapt to different liquid levels in the substrate, the orifice plate 12 of the gas-liquid enhancement unit is positioned below the liquid surface, while the tray 11 is positioned above the liquid surface. The height of the gas-liquid enhancement unit within the reaction tank 1 is adjusted by cranking the crank 27. During adjustment, the crank 27 is rotated, which drives the screw body 24 to rotate along the second screw barrel 26. The screw body 24 rotates synchronously with the tray 11. Through the cooperation of the screw body 24 and the second screw barrel 26, the rotational force is converted into a linear lifting force, driving the tray 25 to move the tray 11 up and down synchronously. During lifting, the mixing pipe 17 with its telescopic structure provides linear guidance and length self-adaptation.

[0048] It also includes a feeding unit, which includes a feeding hopper 28. The feeding hopper 28 is connected to the feed pipe 30 through a valve group 29. The other end of the feed pipe 30 is connected to the inside of the guide cylinder 10 or the lower inner side of the reaction tank 1. The feeding unit feeds the reaction substrate and catalyst into the reaction tank 1. The feeding unit is directly set in the lower part of the reaction tank 1 or inside the feed pipe 30, which allows the reaction substrate to smoothly enter the gas-liquid enhancement unit below.

[0049] A second circulation pump 31 is connected in series between the jet mixer 2 and the heat exchanger 3. The second circulation pump 31 can both balance the pressure of the fluid entering the jet mixer 2 and enhance the pressure of the fluid entering the jet mixer 2, thereby increasing the amount of gas attracted by the jet mixer 2.

[0050] The jet mixer 2 is externally sealed with an outer cover 32; the jet mixer 2 has multiple negative pressure extraction holes 33 inside the outer cover 32; the raw material gas storage tank is connected to the raw material supply pipe valve through a gas metering valve; the outer cover 32 provides reaction gas comprehensively and evenly to the negative pressure extraction area, and the reaction gas is sent into the jet mixer 2 through the multiple negative pressure extraction holes 33; this increases the mixing volume of fluid and reaction gas; when the reaction raw material gas is supplied, the raw material supply pipe valve injects the total amount of gas from a single reaction into the raw material gas storage tank at once through the gas metering valve, and then... The set amount of working gas is injected into the mixing tank 5 through the opening valve 7. After the jet mixer 2 completes one jet mixing and reaction, the unreacted gas re-enters the mixing tank 5. At the same time, the concentration of the reacting gas is monitored in real time by the dimethylamine concentration transmitter 6. When the concentration of the reacting gas is less than the set value, even if the jet mixer 2 sprays the fluid, the reacting gas entering the jet mixer 2 cannot meet the fluid reaction requirements. Therefore, the opening valve 7 needs to respond quickly to replenish the gas, so as to avoid wasting circulation power, prolonging the loop reaction time, and large fluctuations in the concentration of reacting gas in the fluid in each cycle.

[0051] The outer side of the plate base 11 is provided with a sealing ring that fits against the inner wall of the reaction vessel 1; the orifice plate 12 is provided with a gap of 1-3 cm between itself and the inner wall of the reaction vessel 1; the sealing ring can form a gas-liquid separation space inside the reaction vessel 1, which can prevent the reaction gas after gas-liquid separation from covering the liquid interface layer again; the gap between the orifice plate 12 and the reaction vessel 1 allows the orifice plate 12 to enter the liquid surface layer, so that the top surface of the orifice plate 12 is flush with or slightly lower than the liquid surface layer, so that it can be quickly drawn into the mixing unit at the first moment when the bubble interface is generated on the liquid surface, thereby diluting the bubble interface and increasing the concentration of reaction gas in the circulating fluid.

[0052] The jet mixer 2 extends outward from the inside of the reaction vessel 1. An annular seat 34 is integrally formed on the outside of the reaction vessel 1 at the extended end. A threaded hole is formed on the annular seat 34. An annular cover 35 is positioned directly above the annular seat 34. An elastic pressure ring 36 is positioned between the annular cover 35 and the annular seat 34. The jet mixer 2 moves through the annular cover 35 and the annular seat 34. The elastic pressure ring 36 is fitted onto the outside of the jet mixer 2. The annular cover 35 and the annular seat 34 are fastened with bolts. During installation... First, fasten the jet mixer 2 to the guide tube 10. Then, insert the jet mixer 2 from the inside of the reaction tank 1 and screw the guide tube 10 to the first screw 9. Next, fit the elastic pressure ring 36 and the ring cover 35. Then, fix the ring cover 35 to the ring seat 34 with a ring bolt. At this time, due to the compression of the elastic pressure ring 36 by the ring cover 35 and the ring seat 34, the external of the jet mixer 2 and the reaction tank 1 can be sealed. Then, install the outer cover 32 and the input pipeline of the jet mixer 2.

[0053] The above embodiments are merely preferred embodiments of the present invention. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the claims of the present invention are included within the scope of the present invention.

Claims

1. A ring-opening amination reaction system comprising a reaction tank, a jet mixer is mounted on the top of the reaction tank, the input end of the jet mixer is connected to a heat exchanger, the input end of the heat exchanger is connected to the bottom of the reaction tank through a first circulating pump; characterized in that: Also comprising: a gas mixing module comprising a mixing tank provided with a dimethylamine concentration transmitter and an opening degree valve; the opening degree valve is connected with a raw gas storage tank for single amine reaction; the input end of the mixing tank is connected with the output end of an air extraction pump, and the input end of the air extraction pump is connected to the upper part inside the reaction tank; the air suction end of the jet mixer is connected with the output end of the mixing tank; a material guiding unit comprising a first screw cylinder fixed to the top inside of the reaction tank, and a flow guiding cylinder rotatably connected to the inside of the first screw cylinder, and the bottom of the jet mixer is fixed to the inside of the flow guiding cylinder, a gas-liquid strengthening unit slidingly arranged outside the flow guiding cylinder; the gas-liquid strengthening unit comprises a disc seat, and the bottom of the disc seat is fixed with a hole plate through a support column; the disc seat is provided with a gas-liquid separation unit and a plurality of backflow drips; the hole plate is provided with a plurality of concentric and non-equal-diameter ring tubes at the bottom, and a plurality of flow guiding covers are arranged at intervals on the ring tubes and fixed with the hole plate; the bottom of the ring tube is connected to a converging pipe, and the converging pipe is communicated with a mixed liquid pipe; the mixed liquid pipe is fixed with the inner wall of the reaction tank through a support flange; the bottom of the mixed liquid pipe is connected with an adjusting valve outside the reaction tank; the bottom of the reaction tank is provided with an external discharge pipe, and the external discharge pipe is respectively connected with a first circulating pump and a discharge pipe valve; the output ends of the adjusting valve and the first circulating pump are respectively connected to two input ends of a mixing unit; the output end of the mixing unit is connected to the input end of a heat exchanger; the disc seat is higher than the liquid level in the reaction tank, and the hole plate is immersed in the liquid level in the reaction tank; the gas-liquid separation and the outflow of the bubble layer fluid at the liquid level in the reaction tank are realized through the material guiding unit and the gas-liquid strengthening unit, and the fluid at the bottom of the reaction tank is mixed and the gas content of the fluid at the bottom of the reaction tank is strengthened, and the gas content of the liquid level position is diluted, and the gas-liquid mixing is completed in advance before the fluid enters the Venturi jet.

2. The cycloamine reaction system of claim 1, wherein: the mixing unit is a Venturi jet; the output end of the first circulating pump is connected to the input end of the Venturi jet, and the adjusting valve is connected to the negative pressure suction end of the Venturi jet.

3. The loop aminization reaction system of claim 1, wherein: the mixing unit is a proportional valve, and the output ends of the adjusting valve and the first circulating pump are respectively connected to two input ends of the proportional valve.

4. The looped aminolysis reaction system of claim 1, wherein: a support seat body for supporting the gas-liquid strengthening unit is arranged outside the flow guiding cylinder.

5. The looped aminolysis reaction system of claim 1, wherein: the mixed liquid pipe is a telescopic pipe, the outer pipe of the telescopic pipe is fixed with the inner wall of the reaction tank through a support flange; the inner pipe of the telescopic pipe is communicated with the converging pipe; a screw body is rotatably arranged on the side of the disc seat away from the telescopic pipe, and a tray is embedded at the bottom of the screw body and movably abuts against the bottom of the disc seat; the tray and the screw body are fastened through bolts; the top of the screw body is rotatably connected with a second screw cylinder, and a handle is fixed to the top of the second screw cylinder; the second screw cylinder is fixed to the top inside of the reaction tank.

6. The looped aminolysis reaction system of claim 1, wherein: a feeding unit is further included, and the feeding unit comprises a feeding hopper connected with a valve group to a material guiding pipe, and the other end of the material guiding pipe is connected to the inside of the flow guiding cylinder or the inside of the lower part of the reaction tank.

7. The looped aminolysis reaction system of claim 1, wherein: a second circulating pump is further connected in series between the jet mixer and the heat exchanger.

8. The looped aminolysis reaction system of claim 1, wherein: The jet mixer is externally sealed with an outer cover body; a plurality of negative pressure air extraction holes are formed in the inner side of the outer cover body; the raw material gas is connected to the raw material supply pipe valve through a gas metering valve.

9. The looped aminolysis reaction system of claim 1, wherein: The disc seat is externally provided with a sealing ring which is attached to the inner wall of the reaction tank; the hole plate and the inner wall of the reaction tank are provided with a gap of 1-3 cm.

10. The looped aminolysis reaction system of claim 1, wherein: The jet mixer is embedded from the inner side of the reaction tank to the outside, an annular seat is integrally formed at the embedded end of the outer part of the reaction tank, an annular screw hole is formed in the annular seat, an annular cover is arranged directly above the annular seat, an elastic compression ring is arranged between the annular cover and the annular seat, the jet mixer is movably arranged through the annular cover and the annular seat, the elastic compression ring is sleeved on the outer part of the jet mixer, and the annular cover and the annular seat are fastened through bolts.

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