A hydrogenation reaction device applied to sugar alcohol production and a preparation method thereof

Abstract

This application relates to a hydrogenation reactor and preparation method for sugar alcohol production. The reactor includes a reaction vessel containing sugar solution, a drive chamber inside the reaction vessel, and a pneumatic stirring assembly mounted on the inner wall of the drive chamber. The pneumatic stirring assembly includes a rotating vibrating part and a stirring rod assembly. An inlet pipe is provided on the reaction vessel, including a first branch pipe and a second branch pipe. One end of the first branch pipe is connected to a pump, and the other end extends to the bottom of the reaction vessel. The second branch pipe communicates with the drive chamber. The rotating vibrating part includes blades designed to rotate under the influence of airflow inside the second branch pipe, compressing the airflow inside the drive chamber to create a fluctuating pressure difference between the upper and lower surfaces of the rotating vibrating part. By introducing high-speed hydrogen gas into the reaction vessel and using a start-up drive method, the problem of hydrogen leakage due to dynamic seal failure is avoided, while simultaneously improving the stirring capacity of the stirring rod assembly.

Description

Technical Field

[0001] This application relates to the field of sugar alcohol production technology, and in particular to a hydrogenation reaction apparatus and preparation method for sugar alcohol production. Background Technology

[0002] The hydrogenation reaction of sugar alcohols usually refers to the reaction of sugars such as glucose with hydrogen in the presence of a metal catalyst to produce sugar alcohols such as sorbitol. The reaction conditions are mild, with a neutral pH, a temperature of 80–120 ℃, and a hydrogen pressure of 3–8 MPa. Commonly used catalysts are Raney nickel and supported noble metals. It is mainly used in food, pharmaceutical, cosmetic and bio-based chemical raw materials.

[0003] Existing technologies, such as the invention application with application number CN202111404362.3, involve a method for continuous hydrogenation of sugar alcohols in a multi-stage reactor series: the raw sugar solution is adjusted to pH 6-7 by a mixer and then enters the first-stage reactor; the catalyst is also introduced into the first-stage reactor through a mixer; hydrogen gas enters from the bottom of the reactor through a gas feed distributor and comes into full contact with the raw sugar solution and the catalyst; heating and stirring are performed using a heating coil and a stirrer, respectively, to obtain the reaction solution after the first hydrogenation reaction; the reaction solution after the first hydrogenation reaction is repeated in the next-stage reactor in series to continue the hydrogenation reaction, to obtain the final hydrogenation reaction solution; the solution is cooled, filtered for decolorization, ion exchanged, and evaporated for crystallization to obtain the sugar alcohol product; wherein, the next-stage reactor includes at least one stage reactor.

[0004] In the above-mentioned and existing sugar alcohol production processes, hydrogenation reactions mainly use batch reactors with stirring to improve reaction efficiency. However, the traditional method of using a motor to drive the stirring paddle is prone to dynamic sealing failure, posing a risk of hydrogen leakage. Moreover, the conventional single stirring method results in a slow rate of catalytic hydrogenation of the sugar solution, which is difficult to meet industrial requirements. Summary of the Invention

[0005] This application provides a hydrogenation reaction apparatus and preparation method for sugar alcohol production, which can solve the problems of existing methods that use external driving devices to stir sugar solutions, which easily lead to the failure of dynamic seals, and the slow catalytic hydrogenation reaction rate of sugar solutions due to the single rotation stirring method.

[0006] The technical solution of this application is as follows: A hydrogenation reaction apparatus for sugar alcohol production, used to hydrogenate sugar solution to prepare sugar alcohol solution, comprising:

[0007] A reaction vessel containing sugar solution is provided inside. The reaction vessel has a drive chamber inside. A pneumatic stirring assembly is provided on the inner wall of the drive chamber. The pneumatic stirring assembly includes a rotating vibrating part and a stirring rod assembly. One end of the stirring rod assembly is mounted on the rotating vibrating part, and the other end extends to the bottom of the reaction vessel and is suspended in the air.

[0008] The reactor is equipped with an air inlet pipe, which includes a first branch pipe and a second branch pipe. One end of the first branch pipe is connected to a gas pumping device, and the other end extends to the bottom of the reactor to catalytically hydrogenate the sugar solution. The second branch pipe is connected to the drive chamber. The rotating vibrating part includes blades, which are designed to rotate under the impetus of the airflow inside the second branch pipe and compress the airflow inside the drive chamber to form a fluctuating gas pressure difference on the upper and lower surfaces of the rotating vibrating part, causing the rotating vibrating part to vibrate up and down.

[0009] By adopting the above scheme, when it is necessary to prepare sugar alcohol products using the device, high-speed hydrogen gas is introduced into the reactor. Part of the hydrogen gas passes through the first branch pipe to form a low-speed, high-pressure gas flow, which is directly introduced into the reactor and undergoes a catalytic hydrogenation reaction with the sugar solution. The other part passes through the second branch pipe to form a high-speed, low-pressure gas flow, which is introduced into the drive chamber. The high-speed, low-pressure gas flow uses its own kinetic energy to drive the rotating vibrating part inside the drive chamber to rotate. While the rotating part is rotating, the gas flow that has consumed its kinetic energy is ejected into the reactor in the form of a pulsed gas flow, thereby causing pulsed changes in the gas pressure inside the reactor. At the same time, because the gas pressure inside the drive chamber is always relatively small relative to the reactor due to the high-speed flow of hydrogen gas, the gas pressure fluctuations inside the reactor will drive the entire rotating vibrating part to vibrate up and down, which in turn drives the stirring rod assembly connected to the rotating vibrating part to vibrate up and down. This makes the motion of the device more complex during stirring, and at the same time avoids the need to use an additional drive device to drive the stirring device to rotate, saving energy and avoiding the problem of hydrogen leakage due to dynamic seal failure.

[0010] In one embodiment of this application, the driving cavity is a disc-shaped cavity with an open lower end, and the rotating vibration part includes:

[0011] A lifting ring is slidably mounted on the inner wall of the driving cavity in the vertical direction and is coaxial with the driving cavity.

[0012] A rotating disk is eccentrically mounted on the inner wall of the lifting ring;

[0013] A rotating rod, one end of which passes through the rotating disk and is coaxially mounted on the rotating disk. Multiple blades are circumferentially fixedly mounted on one end of the rotating rod, and the other end is connected to the stirring rod assembly. An elastic compensation plate is mounted on the end of the multiple blades away from the rotating rod, and the elastic compensation plate is in contact with the inner wall of the driving cavity.

[0014] By adopting the above scheme, when a high-speed hydrogen gas flow passes through the blades, the kinetic energy of the flow can drive the blades, causing the rotating disk to rotate. Because the rotating disk is eccentrically mounted on the inner wall of the lifting ring, the space between adjacent blades dynamically changes as the blades rotate. As the blades move from the farthest point between the rotating rod and the inner wall of the drive chamber to the closest point, the volume of space between adjacent blades continuously decreases, and the air between adjacent blades is continuously compressed, thus achieving a pressurization process. Finally, when the pressure reaches its maximum, it drives the gas to be ejected from inside the wall. This allows the device to not only utilize airflow to drive the rotation of the stirring assembly, but also avoids the potential failure of dynamic sealing. The blades can expel pulsed airflow, causing the air pressure inside the reactor to change in a pulsed manner. Since the air pressure inside the reactor is always higher than the air pressure inside the drive chamber, and the stirring rod assembly itself has gravity, the upward thrust of the rotating disk by the air pressure inside the reactor causes the other end of the stirring rod assembly to be suspended. When the air pressure inside the reactor increases, it can drive the lifting ring to move up and down, thereby raising the stirring rod assembly. When the air pressure inside the reactor decreases, the stirring rod assembly will descend due to the decrease in upward thrust. Therefore, the pulsed air pressure changes allow the rotating disk to rotate while driving the lifting ring to move up and down inside the drive chamber, thereby causing the stirring rod assembly to rotate and stir while performing vertical up and down movements.

[0015] In one embodiment of this application, an air inlet is provided on one side of the driving cavity, the air inlet is located at the farthest end of the inner wall of the driving cavity from the rotating rod, and is connected to the second branch pipe; an air outlet is provided on the other side of the driving cavity, the air outlet is located at the closest end of the inner wall of the driving cavity to the rotating rod, and is connected to the reaction vessel.

[0016] By placing the air inlet at the farthest end of the inner wall of the drive chamber from the rotating rod, where the gas pressure is lowest, it is easier for the airflow inside the second branch pipe to enter through the air inlet. At the same time, the air outlet is placed at the closest end of the inner wall of the drive chamber to the rotating rod, where the gas is compressed to the maximum, so that the gas can be ejected from the drive chamber at the peak pressure, thus causing a more significant change in the gas pressure inside the reactor.

[0017] In one embodiment of this application, the stirring rod assembly includes:

[0018] A connecting rod, one end of which extends into the drive cavity and is coaxially connected and fixed to the rotating rod, and the other end of which is provided with a cup-shaped limiting member;

[0019] The transmission rod has eccentric rods extending radially on both sides of the other end of the connecting rod. One end of the transmission rod extends into the limiting member and is coaxial with the connecting rod. One end of the transmission rod is rotatably connected to the eccentric rod.

[0020] A stirring rod, one end of which is coaxially connected to the other end of a transmission rod, and the other end extends to the bottom of the reactor;

[0021] The stirring blades are fixedly mounted on the stirring rod along the length of the stirring rod. Multiple sets of stirring blades are provided and spaced apart along the length of the stirring rod.

[0022] By adopting the above scheme, when the blades rotate, they can drive the connecting rod to rotate, and the connecting rod drives the transmission rod to rotate. Since the transmission rod can deflect on the connecting rod, and when the transmission rod rotates, the stirring rod located below it is suspended in the air. The stirring rod can deflect under the action of centrifugal force. Since the liquid level of the mixture inside the reactor will drop as the process proceeds, that is, the resistance of the liquid surface to the stirring rod will also decrease. At this time, the stirring rod can gradually increase the deflection angle while rotating, so that the movement of the stirring rod driving the stirring blades in stirring the sugar solution is more complex.

[0023] In one embodiment of this application, the second branch pipe includes:

[0024] The gas transmission section, one end of which is connected to the first branch pipe via a flow valve;

[0025] The contraction section is connected at one end to one end of the gas delivery section and at the other end to the air inlet.

[0026] By adopting the above scheme, a gas delivery section and a contraction section are set inside the second branch pipe. When the hydrogen gas flows through the contraction section, its velocity increases, thereby increasing its kinetic energy and making it easier to drive the blades. At the same time, the increased velocity also reduces the gas pressure inside the drive cavity, thereby providing a greater pressure difference on both sides of the rotating disk, which makes it easier for the rotating disk to drive the lifting ring to move up and down.

[0027] It also includes a discharge pipe, which is assembled on the reactor. One end of the discharge pipe extends into the interior of the reactor until it is below the surface of the sugar solution, and the other end is located outside the reactor.

[0028] By adopting the above scheme, the increased gas pressure inside the reactor can be used to pump the hydrogenated sugar alcohol out of the reactor, thereby achieving the goal of further saving energy.

[0029] In one embodiment of this application, a circulating cooling assembly is further included, the circulating cooling assembly comprising:

[0030] A cooling coil, which is spiral-shaped and disposed inside the reactor;

[0031] The reactor is equipped with cooling inlet pipes and cooling outlet pipes on both sides of its exterior. One end of each cooling inlet pipe and cooling outlet pipe is connected to both ends of the cooling coil, and the other end of each cooling inlet pipe and cooling outlet pipe is connected to a cooling liquid circulation device.

[0032] By adopting the above scheme, and by introducing coolant into the cooling coil and placing the cooling coil inside the reactor, the temperature inside the reactor can be rapidly reduced after the sugar solution reaction inside the reactor is completed, by introducing coolant into the cooling coil to absorb the heat inside the reactor, thereby improving the industrial production efficiency of the device.

[0033] In one embodiment of this application, a jacket assembly is further included. The jacket assembly includes a heating cavity with a heating medium inside. The heating cavity is sleeved outside the reactor. The inlet and outlet of the heating cavity are connected to a heating medium circulation device. The heating cavity is provided with a plurality of temperature measuring elements at intervals along its own length direction. The plurality of temperature measuring elements are distributed circumferentially along the heating cavity.

[0034] By adopting the above scheme, when it is necessary to heat the reactor to ensure the reaction temperature, a jacket is set outside the reactor and a heating medium is circulated inside the jacket, which can more evenly raise and maintain the temperature inside the reactor to ensure the reaction effect.

[0035] In one embodiment of this application, a plurality of annular grooves are provided on the outside of the reactor, which are spaced apart along the length of the reactor. The annular grooves are coaxial with the reactor and located inside the heating cavity.

[0036] By adopting the above scheme and setting an annular groove outside the reactor, the reactor is heated by the heating medium inside the jacket. Due to the increased heat exchange area, the heating speed of the reactor is improved, thereby increasing production efficiency.

[0037] The second objective of this invention is to provide a hydrogenation reaction preparation method applicable to the production of sugar alcohols.

[0038] The technical solution is as follows: A method for preparing sugar alcohols through hydrogenation reaction in sugar alcohol production, comprising the following steps:

[0039] S1: A measured amount of sugar solution is pumped into the reactor, then a catalyst and water are added to form a reaction mixture. A protective gas is then introduced into the reactor until the oxygen concentration in the reactor is below 1%.

[0040] S2: Introduce heating medium into the jacket assembly to heat the reactor to 130-150 degrees Celsius;

[0041] S3: Continuously introduce 99.99% pure hydrogen into the reactor while stirring the reaction mixture and maintaining the internal pressure of the reactor at 8MPa to form hydrogenated sugar alcohol solution and recover it;

[0042] S4: When the internal pressure of the reactor continues to rise, stop the supply of heating medium and hydrogen, and supply coolant into the circulating cooling system until the reactor returns to room temperature and the remaining hydrogenated sugar alcohol solution is recovered.

[0043] S5: Continuously discharge and recover hydrogen from inside the reactor until the pressure inside the reactor drops to 3MPa;

[0044] S6: Let the reactor stand for three to four hours to recover the catalyst located at the bottom of the reactor, and at the same time vent the remaining gas in the reactor.

[0045] In one embodiment of this application, by eliminating the use of a driving device to drive the stirring device to stir the sugar solution, the problem of hydrogen leakage caused by dynamic seal failure is avoided, thereby ensuring the gas pressure inside the reactor, ensuring reaction efficiency, saving energy, and improving economic benefits.

[0046] In summary, this application includes at least one of the following beneficial technical effects: by setting up a driving device and setting up a driving cavity inside the driving device, when hydrogen is introduced into the device, the high-speed hydrogen fluid can drive the blades inside the driving cavity, thereby driving the stirring rod assembly to rotate. By using a pneumatic drive, it is not necessary to set up an additional driving device to drive the stirring device to rotate, which saves energy and also avoids the possibility of hydrogen leakage due to dynamic sealing.

[0047] By setting up a rotating disk and a lifting ring, when the hydrogen fluid passes through the blades, the rotating disk is eccentrically set on the inner wall of the lifting ring, and the lifting ring is slidably assembled in the drive chamber. As the blades drive the stirring rod assembly to stir and blow out pulsed airflow, pressure fluctuations can be caused inside the reactor. Because the hydrogen flow rate inside the drive chamber is relatively fast, a fluctuating pressure difference is formed on both sides of the rotating disk, which in turn causes the rotating rod assembly to vibrate up and down during rotation.

[0048] By setting up a transmission rod and a connecting rod, the transmission rod can rotate together with the connecting rod when the rotating rod rotates. At the same time, due to the influence of centrifugal force, the transmission rod will deflect while rotating. As the liquid level inside the reactor changes, the deflection angle of the stirring rod assembly will also change, making the movement of the stirring rod more complex and the stirring effect better.

[0049] By setting up a reaction vessel and installing a discharge pipe at the bottom of the reaction vessel, the hydrogenated sugar alcohol liquid obtained from the recovery reaction can be pumped out by the high gas pressure inside the reaction vessel, thereby avoiding the need to set up additional suction equipment to recover the sugar alcohol liquid and further improving the energy efficiency of the device.

[0050] By incorporating a jacket assembly and a circulating cooling assembly, and by introducing a circulating coolant into the reactor and a circulating heating medium into the jacket assembly outside the reactor, the device achieves more uniform and efficient temperature control. Attached Figure Description

[0051] Figure 1 This is a front sectional view of a hydrogenation reactor for sugar alcohol production provided in the first embodiment of this application;

[0052] Figure 2 This is a top sectional view of the drive chamber of a hydrogenation reactor for sugar alcohol production, provided in the first embodiment of this application.

[0053] Figure 3 This is a front sectional view of the drive chamber of a hydrogenation reactor for sugar alcohol production, provided in the first embodiment of this application.

[0054] Figure 4 This is a top view of a hydrogenation reactor for sugar alcohol production provided in the first embodiment of this application;

[0055] Figure 5 This is a plan sectional view of the second branch pipe of a hydrogenation reactor for sugar alcohol production provided in the first embodiment of this application;

[0056] Figure 6 This is a perspective view of a limiting component for a hydrogenation reactor used in the production of sugar alcohols, provided in the first embodiment of this application.

[0057] Figure 7 This is a perspective view of an annular groove in a hydrogenation reactor for sugar alcohol production, provided in the second embodiment of this application.

[0058] Explanation of reference numerals in the attached drawings: 1. Reactor; 11. Inlet pipe; 111. First branch pipe; 112. Second branch pipe; 1121. Gas conveying section; 1122. Contraction section; 12. Discharge pipe; 13. Annular groove; 14. Feed inlet; 15. Pressure measuring port; 16. Exhaust port; 21. Drive chamber; 211. Inlet; 212. Outlet; 22. Pneumatic stirring assembly; 221. Rotary vibrating part; 2211. Lifting ring; 2212. 2213 Rotary disk; 2214 Rotating rod; 2215 Blade; 2216 Elastic compensation plate; 2227 Stirring rod assembly; 2221 Connecting rod; 2222 Transmission rod; 2223 Eccentric rod; 2224 Limiting component; 2225 Stirring rod; 2226 Stirring blade; 4. Circulating cooling assembly; 41 Cooling coil; 42 Cooling inlet pipe; 43 Cooling outlet pipe; 5. Jacket assembly; 51 Heating chamber; 52 Temperature measuring element. Detailed Implementation

[0059] The following is in conjunction with the appendix Figures 1-7 This application provides a further detailed description of a hydrogenation reactor for the production of sugar alcohols.

[0060] Example 1, please refer to Figure 1 , Figure 2 , Figure 3 and Figure 4 This application provides a hydrogenation reaction apparatus for sugar alcohol production, used to hydrogenate sugar solution to prepare sugar alcohol solution. It includes: a reaction vessel 1 containing sugar solution; a driving chamber 21 inside the reaction vessel 1; a pneumatic stirring assembly 22 on the inner wall of the driving chamber 21; the pneumatic stirring assembly 22 including a rotating vibrating part 221 and a stirring rod assembly 222; one end of the stirring rod assembly 222 is mounted on the rotating vibrating part 221, and the other end extends to the bottom of the reaction vessel 1 and is suspended; an air inlet pipe 11 is provided on the reaction vessel 1, including a first branch pipe 111 and a second branch pipe 112; one end of the first branch pipe 111 is connected to a pumping device, and the other end extends to the bottom of the reaction vessel 1 to connect with... The sugar solution undergoes a catalytic hydrogenation reaction. The second branch pipe 112 is connected to the drive chamber 21. The rotating vibration part 221 includes blades 2214. The blades 2214 are designed to rotate under the impetus of the airflow inside the second branch pipe 112 and compress the airflow inside the drive chamber 21 to form a fluctuating pressure difference on the upper and lower surfaces of the rotating vibration part 221, causing the rotating vibration part 221 to vibrate up and down. By setting a drive chamber inside the reactor 1 and dividing the hydrogen into two parts, a low-speed high-pressure part and a high-speed low-pressure part, which are respectively introduced into the drive chamber 21 and the reactor 1, the hydrogen airflow drives the stirring rod assembly 222 to rotate, effectively avoiding the problem of dynamic seal failure. At the same time, it makes the movement of the stirring rod assembly 222 more complex and the stirring effect better.

[0061] Please see Figure 1 and Figure 2 The driving cavity 21 is a disc-shaped cavity with an open lower end. The rotating vibration part 221 includes a lifting ring 2211, a rotating disk 2212, and a rotating rod 2213. The lifting ring 2211 is slidably mounted on the inner wall of the driving cavity 21 in the vertical direction and is coaxial with the driving cavity 21. The rotating disk 2212 is eccentrically mounted on the inner wall of the lifting ring 2211. One end of the rotating rod 2213 passes through the rotating disk 2212 and is coaxially mounted on the rotating disk. One end of the rotating rod 2213 is circumferentially fixed with multiple blades 2214, and the other end is connected to the stirring rod assembly. Connected to 222, multiple blades 2214 are equipped with elastic compensation plates 2215 at the ends away from the rotating rod 2213. The elastic compensation plates 2215 are in contact with the inner wall of the driving cavity 21. By setting an eccentric rotating disk 2212, the volume between two adjacent blades 2214 will change dynamically when the blades 2214 on the rotating disk 2212 rotate. This allows the blades 2214 to blow out pulsed airflow when rotating, thereby increasing the internal air pressure fluctuation of the reactor 1 and driving the stirring rod assembly 222 to vibrate continuously when rotating.

[0062] In this embodiment, the gas pumping device can be a gas pump connected to a hydrogen storage cylinder, and the gas pump can be used to pump the hydrogen stored in the hydrogen storage cylinder to the reactor 1.

[0063] The blade 2214 can be made of sheet-like spring steel material and is set in the drive cavity 21. Its outer diameter is 200mm and there are a total of 6 inclined blades 2214. The impact surface of the blade 2214 is at an angle of about 45° to the direction of the hydrogen jet, so as to achieve efficient conversion of kinetic energy into torque.

[0064] The intake pipe 11 is externally connected to a high-pressure hydrogen source with a pressure of 8.5-9.0MPa. The inner diameter of the gas transmission section 1121 is 50mm (DN50), and the inner diameter of the outlet of the contraction section 1122 at the end is designed to be 20mm.

[0065] When high-pressure hydrogen enters from the gas delivery section 1121 with an inner diameter of 50 mm and passes through the contraction section 1122 with an outlet inner diameter of only 20 mm, according to the continuity equation of fluid mechanics and Bernoulli's principle, the pressure energy of the hydrogen will be converted into a large amount of kinetic energy, forming a high-speed jet at the outlet of the contraction section 1122. It is calculated that under the driving force of a pressure difference of about 0.5 MPa, the instantaneous flow velocity of hydrogen at the outlet can reach 50-70 m / s, and the resulting mass flow rate is about 70-80 kg / h.

[0066] This high-speed hydrogen jet directly impacts the inclined blades 2214 of the turbine fan blades with a diameter of 200 mm, generating a continuous and stable impact force. The torque generated by this impact force is sufficient to overcome the rotational inertia of the stirring device and the stirring resistance brought by the sugar solution, thereby driving the stirring device to rotate and oscillate effectively at the designed speed (e.g., 60-100 rpm), ensuring that the hydrogen is fully dispersed and contacted in the sugar solution, thus ensuring the efficient progress of the hydrogenation reaction.

[0067] Please see Figure 2 An air inlet 211 is provided on one side of the driving cavity 21. The air inlet 211 is located at the farthest end of the inner wall of the driving cavity 21 from the rotating rod 2213 and is connected to the second branch pipe 112. An air outlet 212 is provided on the other side of the driving cavity 21. The air outlet 212 is located at the closest end of the inner wall of the driving cavity 21 from the rotating rod 2213 and is connected to the reactor 1. By setting the air inlet 211 at the farthest end of the inner wall of the driving cavity 21 from the rotating rod 2213, the gas pressure is the lowest at this point, which facilitates the airflow inside the second branch pipe 112 to enter through the air inlet 211. At the same time, by setting the air outlet 212 at the closest end of the inner wall of the driving cavity 21 to the rotating rod 2213, the amount of gas compressed reaches its maximum, so that the gas can be ejected from the driving cavity 21 at the peak pressure, thereby causing a more significant change in the gas pressure inside the reactor 1.

[0068] Please see Figure 1 The stirring rod assembly 222 includes: a connecting rod 2221, a transmission rod 2222, a stirring rod 2225, and a stirring blade 2226. One end of the connecting rod 2221 extends into the drive cavity 21 and is coaxially connected and fixed to the rotating rod 2213. The other end of the connecting rod 2221 is provided with a cup-shaped limiting member 2224. Both sides of the other end of the connecting rod 2221 are provided with eccentric rods 2223 extending radially. One end of the transmission rod 2222 extends into the limiting member 2224 and is coaxial with the connecting rod 2221. One end of the transmission rod 2222 is rotatably connected to the eccentric rod 2223. One end of the stirring rod 2225 is connected to the transmission rod 2226. The other end of the rod 2222 is coaxially connected and extends to the bottom of the reactor 1. The stirring blade 2226 is fixedly mounted on the stirring rod 2225 along the length of the stirring rod 2225. Multiple sets of stirring blades 2226 are provided and spaced apart along the length of the stirring rod 2225. When the blade 2214 rotates, the connecting rod 2221 and the transmission rod 2222, which can be relatively deflected, allow the stirring rod 2225 to deflect under the action of centrifugal force. This allows the stirring rod 2225 to gradually change its deflection angle while rotating, making the movement of the stirring rod 2225 driving the stirring blade 2226 in stirring the sugar solution more complex.

[0069] Please see Figure 5 The second branch pipe 112 includes a gas delivery section 1121 and a contraction section 1122. One end of the gas delivery section 1121 is connected to the first branch pipe 111 through a flow valve. One end of the contraction section 1122 is connected to one end of the gas delivery section 1121, and the other end is connected to the air inlet 211. By setting the gas delivery section 1121 and the contraction section 1122 inside the second branch pipe 112, the hydrogen gas flow velocity is faster when passing through the contraction section 1122, thereby increasing the kinetic energy and making it easier to push the blade 2214. At the same time, it will reduce the gas pressure inside the drive cavity 21, thereby providing a larger pressure difference on both sides of the rotating disk 2212.

[0070] Please continue reading. Figure 1 It also includes a discharge pipe 12, which is assembled on the reactor 1. One end of the discharge pipe 12 extends into the reactor 1 until it is below the liquid surface of the sugar solution, and the other end is located outside the reactor 1. By utilizing the increased gas pressure inside the reactor 1, the hydrogenated sugar alcohol after the reaction can be pumped out of the reactor 1 to further save energy.

[0071] Please continue reading. Figure 1 It also includes a circulating cooling assembly 4, which includes a cooling coil 41. The cooling coil 41 is spiral-shaped and is disposed inside the reactor 1. Cooling inlet pipes 42 and cooling outlet pipes 43 are provided on both sides of the outside of the reactor 1. One end of the cooling inlet pipe 42 and the cooling outlet pipe 43 are respectively connected to the two ends of the cooling coil 41, and the other end of the cooling inlet pipe 42 and the cooling outlet pipe 43 are connected to a cooling liquid circulation device. By circulating the cooling liquid into the cooling coil 41, after the sugar solution inside the reactor 1 has reacted, the cooling liquid absorbs the heat inside the reactor 1, which can cause the temperature inside the reactor 1 to drop rapidly.

[0072] In this embodiment, the coolant can be cold water, and the coolant circulation device can be a water pump and a water storage tank. A cooling plate is installed on the water storage tank, and the water pump pumps the cooled water inside the water storage tank into the cooling coil 41. The water that has absorbed heat flows back to the water storage tank through the cooling outlet pipe 43.

[0073] Please continue reading. Figure 1It also includes a jacket assembly 5, which includes a heating chamber 51 with a heating medium inside. The heating chamber 51 is fitted outside the reactor 1. The inlet and outlet of the heating chamber 51 are connected to a heating medium circulation device. The heating chamber 51 is provided with a plurality of temperature measuring elements 52 at intervals along its length. The plurality of temperature measuring elements 52 are distributed circumferentially along the heating chamber 51. By circulating the heating medium inside the reactor 1, the temperature inside the reactor 1 can be raised and maintained more evenly to ensure the reaction effect.

[0074] In this embodiment, the heating medium can be water vapor, and the heating medium circulation device can be a water storage bottle and an air pump. An electric heating wire is installed inside the water storage bottle so that the water inside the water storage bottle is heated and evaporated to form high-pressure, high-temperature water vapor, which is then introduced into the jacket assembly 5 through the air pump.

[0075] Example 2 has the same basic structure as Example 1, but differs in that it aims to improve the heat exchange efficiency of reactor 1.

[0076] Please see Figure 7 The reactor 1 has multiple annular grooves 13 spaced apart along the length of the reactor 1. The annular grooves 13 are coaxial with the reactor 1 and located inside the heating chamber 51. By setting annular grooves on the outside of the reactor 1, the heat exchange area between the reactor 1 and the heating medium is increased, thereby improving the speed at which the device heats the reactor 1.

[0077] The second objective of this invention is to provide a hydrogenation reaction preparation method applicable to the production of sugar alcohols.

[0078] To achieve the above objectives, the technical solution of this application is as follows: A method for preparing sugar alcohol liquid using a hydrogenation reaction apparatus for sugar alcohol production, comprising the following steps:

[0079] S1: A measured amount of sugar solution is pumped into reactor 1, then a catalyst and water are added to form a reaction mixture. A protective gas is then introduced into reactor 1 until the oxygen concentration in reactor 1 is less than 1%.

[0080] S2: Introduce heating medium into the jacket assembly 5 to heat the reactor 1 to 130-150 degrees Celsius;

[0081] S3: Continuously introduce 99.99% pure hydrogen into reactor 1 while stirring the reaction mixture, and maintain the pressure inside reactor 1 at 8MPa to form hydrogenated sugar alcohol solution and recover it;

[0082] S4: When the internal pressure of reactor 1 continues to rise, stop the supply of heating medium and hydrogen, and supply coolant into the circulating cooling component 4 until reactor 1 returns to room temperature and the remaining hydrogenated sugar alcohol liquid is recovered.

[0083] S5: Continuously discharge and recover hydrogen from inside reactor 1 until the pressure inside reactor 1 drops to 3MPa;

[0084] S6: Let reactor 1 stand for three to four hours to recover the catalyst located at the bottom of reactor 1, and at the same time vent the remaining gas in reactor 1.

[0085] The reactor 1 is equipped with a feed inlet 14, a pressure measuring port 15, and an vent 16 at its upper end. The feed inlet 14 is equipped with a feed valve to control the amount of catalyst and water added. The pressure measuring port 15 is equipped with a pressure sensor to monitor whether the pressure inside the reactor 1 meets the standard in real time. The vent 16 is equipped with a vent valve to release excess hydrogen gas from the reactor 1.

[0086] In this embodiment, the sugar solution with a content greater than 95% and a concentration of 40% after decolorization and filtration in the previous process is pumped to the metering tank. After being metered, it is pumped into the reaction vessel 1. Then, hydrogen and catalyst are introduced into the reaction vessel 1. The metered catalyst is mixed with water and added through the feed port 14 and mixed with the sugar solution. The catalyst can be Reynolds framework nickel. A nitrogen pipeline is set outside the reaction vessel 1, and nitrogen is introduced into the reaction vessel 1 through the nitrogen pipeline to replace the oxygen and other gases inside the reaction vessel 1. At the same time, an oxygen content detector is set to detect the oxygen content in the reaction vessel 1. When the oxygen content detector detects that the concentration reaches 1%, the nitrogen supply is stopped.

[0087] Simultaneously, a heating medium is introduced into the jacket assembly 5 to heat the reactor 1 to 145 degrees Celsius. At this time, pure high-pressure hydrogen is introduced. Due to the introduction of hydrogen, the stirring device 2 starts stirring and the pressure is maintained at 8 MPa. At this time, the sugar solution and hydrogen undergo a hydrogen absorption reaction. Since the hydrogen is no longer consumed when the reaction stops, the pressure inside the reactor 1 will rise. It is necessary to keep the hydrogen continuously added. By adjusting the pressure inside the reactor 1, the hydrogen absorption stops. At this time, the introduction of steam and hydrogen is stopped, stirring is stopped, and coolant is introduced for cooling. The excess hydrogen is reduced to 3 MPa through the pressure reducing valve and placed in the hydrogen recovery buffer tank as part of the hydrogen for the next reactor addition. When the pressure inside the reactor is 3 MPa, the recovery of hydrogen is stopped. The residual pressure is used to force the material out of the reactor 1. After the material stays in the settling tank for about 3-4 hours, the remaining trace amount of hydrogen inside the reactor 1 is discharged through the vent 16.

[0088] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A hydrogenation reaction apparatus for sugar alcohol production, used to hydrogenate sugar solution to prepare sugar alcohol solution, characterized in that, include: A reaction vessel (1) containing sugar solution is provided inside. A drive chamber (21) is provided inside the reaction vessel (1). A pneumatic stirring assembly (22) is provided on the inner wall of the drive chamber (21). The pneumatic stirring assembly (22) includes a rotating vibration part (221) and a stirring rod assembly (222). One end of the stirring rod assembly (222) is mounted on the rotating vibration part (221), and the other end extends to the bottom of the reaction vessel (1) and is suspended in the air. The reactor (1) is provided with an air inlet pipe (11), which includes a first branch pipe (111) and a second branch pipe (112). One end of the first branch pipe (111) is connected to a pumping device, and the other end extends to the bottom of the reactor (1) to catalytically hydrogenate the sugar solution. The second branch pipe (112) is connected to the driving cavity (21). The rotating vibration part (221) includes blades (2214). The blades (2214) are designed to rotate under the push of the airflow inside the second branch pipe (112) and compress the airflow inside the driving cavity (21) to form a fluctuating air pressure difference on the upper and lower surfaces of the rotating vibration part (221), so that the rotating vibration part (221) vibrates up and down. The driving cavity (21) is a disc-shaped cavity with an open lower end, and the rotating vibration part (221) includes: The lifting ring (2211) is slidably mounted on the inner wall of the driving cavity (21) in the vertical direction and is coaxial with the driving cavity (21). A rotating disk (2212) is eccentrically mounted on the inner wall of the lifting ring (2211); A rotating rod (2213) has one end that passes through the rotating disk (2212) and is coaxially mounted on the rotating disk (2212). One end of the rotating rod (2213) is circumferentially fixedly equipped with a plurality of blades (2214), and the other end is connected to the stirring rod assembly (222). The ends of the plurality of blades (2214) away from the rotating rod (2213) are equipped with elastic compensation plates (2215), and the elastic compensation plates (2215) are in contact with the inner wall of the driving cavity (21). An air inlet (211) is provided on one side of the drive cavity (21), and the air inlet (211) is located at the farthest end of the inner wall of the drive cavity (21) from the rotating rod (2213) and is connected to the second branch pipe (112). An air outlet (212) is provided on the other side of the drive cavity (21), and the air outlet (212) is located at the closest end of the inner wall of the drive cavity (21) to the rotating rod (2213) and is connected to the reaction vessel (1).

2. The hydrogenation reactor for sugar alcohol production according to claim 1, characterized in that, The stirring rod assembly (222) includes: A connecting rod (2221) is provided at one end, which extends into the drive cavity (21) and is coaxially connected and fixed with the rotating rod (2213). A cup-shaped limiting member (2224) is provided on the outside of the other end of the connecting rod (2221). The transmission rod (2222) has eccentric rods (2223) extending radially on both sides of the other end of the connecting rod (2221). One end of the transmission rod (2222) extends into the limiting member (2224) and is coaxial with the connecting rod (2221). One end of the transmission rod (2222) is rotatably connected to the eccentric rod (2223). A stirring rod (2225) is provided, with one end of the stirring rod (2225) coaxially connected to the other end of the transmission rod (2222), and the other end extending to the bottom of the reactor (1). A stirring blade (2226) is fixedly mounted on the stirring rod (2225) along the length direction of the stirring rod (2225). Multiple sets of stirring blades (2226) are provided and are spaced apart along the length direction of the stirring rod (2225).

3. The hydrogenation reactor for sugar alcohol production according to claim 1, characterized in that: The second branch pipe (112) includes: Gas transmission section (1121), one end of which is connected to the first branch pipe (111) via a flow valve; The contraction section (1122) is connected at one end to one end of the gas delivery section (1121) and at the other end to the air inlet (211).

4. A hydrogenation reactor for sugar alcohol production according to claim 1, characterized in that: It also includes a discharge pipe (12), which is mounted on the reactor (1). One end of the discharge pipe (12) extends into the reactor (1) until it is below the surface of the sugar solution, and the other end is located outside the reactor (1).

5. A hydrogenation reactor for sugar alcohol production according to claim 1, characterized in that: It also includes a circulating cooling assembly (4), which comprises: Cooling coil (41), the cooling coil (41) is spiral-shaped and is disposed inside the reactor (1); The reactor (1) is provided with a cooling inlet pipe (42) and a cooling outlet pipe (43) on both sides of the outside. One end of the cooling inlet pipe (42) and the cooling outlet pipe (43) are respectively connected to the two ends of the cooling coil (41), and the other end of the cooling inlet pipe (42) and the cooling outlet pipe (43) are connected to the cooling liquid circulation equipment.

6. A hydrogenation reactor for sugar alcohol production according to claim 5, characterized in that: It also includes a jacket assembly (5), which includes a heating chamber (51) with a heating medium inside. The heating chamber (51) is fitted outside the reactor (1). The inlet and outlet of the heating chamber (51) are connected to a heating medium circulation device. The heating chamber (51) is provided with a plurality of temperature measuring elements (52) at intervals along its own length direction. The plurality of temperature measuring elements (52) are distributed circumferentially along the heating chamber (51).

7. A hydrogenation reactor for sugar alcohol production according to claim 6, characterized in that: The reactor (1) has multiple annular grooves (13) spaced apart along the length of the reactor (1) on its exterior. The annular grooves (13) are coaxial with the reactor (1) and located inside the heating chamber (51).

8. A method for preparing sugar alcohols through a hydrogenation reaction in sugar alcohol production, comprising preparing a sugar alcohol liquid using a hydrogenation reaction apparatus for sugar alcohol production as described in any one of claims 6-7, characterized in that, Includes the following steps: S1: A measured amount of sugar solution is pumped into the reaction vessel (1), and then a catalyst and water are added to form a reaction mixture. Then, a protective gas is introduced into the reaction vessel (1) until the oxygen concentration in the reaction vessel (1) is less than 1%. S2: Introduce heating medium into the jacket assembly (5) to heat the reactor (1) to 130-150 degrees. S3: Continuously introduce hydrogen gas with a purity of 99.99% into the reactor (1) while stirring the reaction mixture, and maintain the pressure inside the reactor (1) at 8MPa to form hydrogenated sugar alcohol liquid and recover it; S4: When the internal pressure of the reactor (1) continues to rise, stop the supply of heating medium and hydrogen, and supply coolant into the circulating cooling assembly (4) until the reactor (1) returns to room temperature and the remaining hydrogenated sugar alcohol liquid is recovered. S5: Continuously discharge and recover the hydrogen inside the reactor (1) until the pressure inside the reactor (1) drops to 3MPa; S6: Let the reactor (1) stand for three to four hours, recover the catalyst located at the bottom of the reactor (1), and at the same time vent the remaining gas in the reactor (1).

Images