Catalyst recovery and treatment unit for tertiary amine production
By designing a catalyst recovery and treatment device, the problems of uneven catalyst activation and powder contamination in tertiary amine production were solved, achieving uniform catalyst activation and effective separation, and improving the stability and safety of the production system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANDONG ZHUOCHENG CHEM CO LTD
- Filing Date
- 2025-09-12
- Publication Date
- 2026-07-31
AI Technical Summary
In the production of tertiary amines, existing technologies suffer from insufficient reduction uniformity and activation of catalysts, which can easily lead to byproduct contamination and the entry of powdered catalysts into downstream equipment, resulting in safety hazards and production instability.
A catalyst recovery and treatment device was designed, which includes an activation unit, a separation unit, and a tail gas treatment unit. The gas-solid contact efficiency is improved by using a gas distribution plate and a composite stirring device, and the catalyst is graded and separated by a cyclone and a sieve plate separator to ensure uniform activation and effective separation.
This achieves uniform activation and effective separation of the catalyst, preventing powder from entering subsequent reactors, improving the stability and safety of the production system, and ensuring the activity and selectivity of the catalyst.
Smart Images
Figure CN224573756U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the technical field of tertiary amine production equipment, specifically relating to a catalyst recovery and treatment device for tertiary amine production. Background Technology
[0002] Tertiary amines are key raw materials in petrochemical, pharmaceutical, and pesticide industries, and are in high demand. During the production of tertiary amines, the catalyst is prone to oxidation after amination reaction, which leads to a decrease in activity. It is necessary to restore the activity through reduction or activation treatment in order to achieve the purpose of reuse.
[0003] In the prior art, the catalyst reduction device disclosed in patent CN213348811U achieves direct reduction of the catalyst through components such as a reduction reactor and a Roots blower, eliminating the activation step of the amination reactor, shortening the production time. During the reduction process, the bubbling of the Roots blower and the stirring of the material ensure uniform reaction between hydrogen and the catalyst, guaranteeing the reduction effect of the catalyst. However, it requires the introduction of fatty alcohol as a liquid medium for reduction to improve the reduction reaction efficiency. But it does not take into account that the catalyst is in the activation stage and its activity is unknown. Introducing reactants in advance will lead to by-products, making the selectivity of the subsequent formal reaction extremely poor.
[0004] The catalyst activation device for tertiary amine production disclosed in patent CN213726553U uses a motor to drive a stirring shaft and stirring rod to achieve stirring and heating of the catalyst, which improves the heating uniformity of the activation process and reduces equipment vibration through a shock-absorbing structure. This device mainly optimizes the heating uniformity of the activation process to achieve full activation of the catalyst. However, it does not take into account the sufficient contact between the gas and the catalyst during the activation process, making it difficult to ensure the completeness of the activation reaction and resulting in a long activation time.
[0005] In summary, while existing technologies can improve reduction efficiency and uniformity by introducing reaction media or optimizing mechanical structures, they overlook the core defect that introducing reactants during the activation stage can lead to a severe decrease in catalyst selectivity due to byproduct contamination. They also ignore the safety hazards caused by catalyst wear during use, which can lead to powdered catalyst entering downstream equipment. These issues restrict the lifespan of the catalyst and the continuity and economy of tertiary amine production. Therefore, there is an urgent need for a catalyst recovery and treatment device for tertiary amine production to solve the above problems. Utility Model Content
[0006] To overcome the problems of limited catalyst reduction uniformity and potential safety hazards caused by powdered catalysts in existing technologies, this invention provides a catalyst recovery and treatment device for tertiary amine production, which ensures the uniformity of activation, achieves catalyst separation, and guarantees the stability of subsequent equipment.
[0007] The specific technical solution of the catalyst recovery and treatment device for tertiary amine production described in this utility model is as follows:
[0008] A catalyst recovery and treatment device for tertiary amine production includes an activation unit, a separation unit, and a tail gas treatment unit connected in sequence to the activation unit.
[0009] The activation unit includes a reduction tank, the top of which is connected to a nitrogen pipeline and a fresh catalyst injection pipeline. The reduction tank is also equipped with a pipeline connected to a settling vessel for transporting the settled catalyst to the activation unit for activation treatment. Furthermore, a nitrogen inlet regulating valve A is installed on the nitrogen pipeline, located on the section of the pipeline before the reduction tank.
[0010] The lower side wall of the reduction tank is connected to a hydrogen pipeline, a gas distribution plate is provided at the bottom of the reduction tank, a stirring device is installed inside the reduction tank, and a hydrogen inlet regulating valve is provided on the hydrogen pipeline.
[0011] The exhaust gas treatment unit includes an exhaust gas filter, a condenser, and a gas-liquid separator connected in sequence. The gas-liquid separator has a built-in wire mesh demister and a jacketed structure. Both the condenser and the gas-liquid separator use circulating water for cooling and condensation.
[0012] The separation unit includes a primary cyclone separator and a secondary sieve plate separator connected in sequence. The top of the primary cyclone separator is connected to the bottom of the reduction tank through a feed pipe on the top side wall. A reflux pipeline is provided at the top and connected to a nitrogen pipeline. A nitrogen filter is provided on the reflux pipeline to filter out small-diameter catalyst particles and realize the recycling of nitrogen.
[0013] The secondary sieve plate separator is equipped with a sieve inside, a sight glass on the upper side wall, and is connected to the catalyst delivery pipeline at the bottom. The secondary sieve plate separator is used to filter large agglomerated catalyst particles, and the sight glass is used to observe the accumulated amount of large agglomerated catalyst particles. It is periodically emptied, and the discharged large agglomerated catalyst particles can be preliminarily crushed again and put back into the reduction tank for activation and use.
[0014] Preferably, the gas distribution plate has oblique holes. The bottom gas distribution plate is mainly used for hydrogen distribution to avoid gas concentration impacting the catalyst bed. The impeller of the stirring device is a combination of a bottom anchor impeller and an upper propeller. The bottom uses an anchor impeller to rotate close to the bottom of the tank to prevent catalyst from depositing and abrading at the bottom. A small propeller is set at the top to break the rising hydrogen bubbles into tiny bubbles and evenly disperse the bubbles into the catalyst suspension layer to enhance gas-solid contact. Furthermore, the gas distribution plate is annular, with the oblique holes tilted at an angle of 30°-45° towards the tank wall of the reduction tank. The position of the impeller of the stirring device is staggered from the bottom gas distribution plate, with the impeller 10-15cm above the gas distribution plate to avoid the airflow directly impacting the rotating impeller and forming turbulence. At the same time, the negative pressure generated by the rotation of the impeller is used to draw the gas into the catalyst particle group to improve the contact efficiency.
[0015] Preferably, the jacket of the gas-liquid separator is connected to the circulating water inlet pipe, the bottom of the jacket of the gas-liquid separator is provided with a pipe connected to the shell side of the condenser, and the top of the shell side of the condenser is connected to the circulating water outlet pipe. The circulating water condensation process is as follows: the circulating water after the heat exchange of the gas-liquid separator is completed enters the shell side of the condenser for the initial condensation of the exhaust gas. In addition, the circulating water and gas in the gas-liquid separator and condenser flow in a convective manner.
[0016] Preferably, the top of the gas-liquid separator is provided with a branch line for returning to the reduction tank, and the branch line is provided with a return hydrogen regulating valve and a circulation pump; the top of the gas-liquid separator is also provided with a gas delivery pipeline for sending the gas generated during the reduction process to be used or incinerated.
[0017] Preferably, a level gauge is installed at the bottom of the gas-liquid separator and connected to the drain pipe at the bottom. The level gauge is used to monitor the amount of condensate in the exhaust gas, and thus monitor the catalyst reduction progress.
[0018] Preferably, the side wall of the primary cyclone separator is provided with an air inlet connected to a nitrogen pipeline to ensure the separation effect of catalyst particles during the cyclone separation process.
[0019] Preferably, a filter tank is installed on the pipeline connecting the settling tank and the reduction tank. The top of the settling tank is connected to the nitrogen pipeline, and the bottom of the filter tank is connected to the drain pipeline. An inclined filter baffle is installed inside the filter tank to achieve preliminary separation of the catalyst and residual amination liquid, preventing the amination liquid from entering the reduction tank and causing side reactions, which would lead to a decrease in catalyst reduction efficiency and affect the catalyst reuse effect and lifespan. At the same time, the inclined filter baffle design allows the catalyst to enter the delivery pipeline by gravity.
[0020] Preferably, a pressure relief valve assembly is also provided at the top of the reduction tank. The pressure relief valve assembly consists of a main pressure relief valve and a pressure sensor. Furthermore, the outlet of the main pressure relief valve is provided with a pipeline connected to the tail gas filter for conveying the gas generated during pressure relief. The pressure sensor and the inlet regulating valve on the nitrogen pipeline form a control loop to facilitate the pressurized delivery of the catalyst to the downstream unit.
[0021] Preferably, the nitrogen pipeline is provided with a branch connected to the secondary sieve plate separator, and a nitrogen inlet regulating valve B is provided on the branch. A pressure gauge is provided at the top of the secondary sieve plate separator, and the pressure gauge can form a control loop with the nitrogen inlet regulating valve B to realize the pressure delivery of the catalyst in the secondary sieve plate separator to the amination reactor for recycling. A branch is provided at the bottom to connect to the gas delivery pipeline.
[0022] Preferably, both the nitrogen filter and the exhaust gas filter are equipped with two parallel filters, one active and one standby.
[0023] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0024] (1) The catalyst recovery and treatment device for tertiary amine production of this utility model can immediately classify and separate the materials after the catalyst is activated. The cyclone separator effectively removes the gas phase fine powder that will cause blockage and pollution, while the sieve plate separator filters and recovers the agglomerated catalyst that can be reused. This prevents the powder from entering the subsequent amination reactor from the source, avoids problems such as product pollution, equipment wear and pressure drop, and greatly improves the stability and safety of the entire production system.
[0025] (2) The catalyst recovery and treatment device for tertiary amine production of this utility model has a gas distribution plate with an inclined hole design to avoid concentrated impact of gas on the catalyst bed. Combined with the composite stirring design, it enhances the gas-solid mass transfer efficiency, so that hydrogen and catalyst particles can be in contact more fully and evenly. Moreover, there is no need to introduce liquid medium, which ensures the activity and selectivity of the catalyst in subsequent reactions. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of the catalyst recovery and treatment device for the production of tertiary amines according to this utility model;
[0027] Figure 2 This is a top view of the gas distribution plate at the bottom of the reduction tank in this utility model;
[0028] Figure 3 This is a cross-sectional view of the gas distribution plate at the bottom of the reduction tank near the tank wall in this utility model.
[0029] In the diagram: 1. Reduction tank; 2. Primary cyclone separator; 3. Secondary sieve plate separator; 301. Sieve; 302. Sight glass; 4. Condenser; 5. Gas-liquid separator; 501. Wire mesh demister; 502. Level gauge; 6. Filter tank; 7. Settling tank; 8. Tail gas filter; 9. Nitrogen filter; 10. Nitrogen pipeline; 11. Hydrogen pipeline; 12. Fresh catalyst injection pipeline; 13. Drainage pipeline; 4. Pressure relief valve assembly; 15. Stirring device; 16. Gas distribution plate; 1601. Inclined hole; 17. Circulating water input pipeline; 18. Circulating water output pipeline; 19. Gas delivery pipeline; 20. Catalyst delivery pipeline; 21. Pressure gauge; 22. Sewage discharge pipeline; 23. Nitrogen inlet regulating valve A; 24. Return hydrogen regulating valve; 25. Hydrogen inlet regulating valve; 26. Nitrogen inlet regulating valve B; 27. Circulating pump. Detailed Implementation
[0030] The specific technical solution of this utility model will be further described below with reference to the accompanying drawings.
[0031] like Figures 1-3 As shown, the catalyst recovery and treatment device for tertiary amine production includes an activation unit, a separation unit, and a tail gas treatment unit connected in sequence. The activation unit includes a reduction tank 1, the top of which is connected to a nitrogen pipeline 10 and a fresh catalyst injection pipeline 12, and the lower side wall is connected to a hydrogen pipeline 11. The tail gas treatment unit includes a tail gas filter 8, a condenser 4, and a gas-liquid separator 5 connected in sequence. The separation unit includes a primary cyclone separator 2 and a secondary sieve plate separator 3 connected in sequence. The top of the primary cyclone separator 2 is connected to the bottom of the reduction tank 1 through a feed pipe on the top side wall, and the side wall is provided with an air inlet connected to the nitrogen pipeline 10. The secondary sieve plate separator 3 is provided with a screen 301 inside, and the bottom is connected to the catalyst delivery pipeline 20.
[0032] The reduction tank 1 is connected to the settling tank 7 via the filter tank 6. The top of the settling tank 7 is connected to the nitrogen pipeline 10, and the bottom of the filter tank 6 is connected to the drain pipeline 13. An inclined filter baffle is installed inside the filter tank 6. The top of the reduction tank 1 is also equipped with a pressure relief valve group 14, which consists of a main pressure relief valve and a pressure sensor. The outlet of the main pressure relief valve is provided with a pipeline connected to the exhaust gas filter 8.
[0033] The nitrogen pipeline 10 is equipped with a nitrogen inlet regulating valve A23 on the section before it enters the reduction tank 1, and the hydrogen pipeline 11 is equipped with a hydrogen inlet regulating valve 25; the nitrogen pipeline 10 is equipped with a branch connected to the secondary sieve plate separator 3, and a nitrogen inlet regulating valve B26 is installed on the branch.
[0034] The bottom of the reduction tank 1 is provided with an air distribution plate 16, and the air distribution plate 16 has an oblique hole 1601. The reduction tank 1 is equipped with a stirring device 15, and the blades of the stirring device 15 are a bottom anchor type combined with an upper propeller.
[0035] The gas-liquid separator 5 has a jacketed structure and a built-in wire mesh demister 501. The jacket of the gas-liquid separator 5 is connected to the circulating water inlet pipe 17. The bottom of the jacket is provided with a pipe connected to the shell side of the condenser 4. The top of the shell side of the condenser 4 is connected to the circulating water outlet pipe 18.
[0036] The first-stage cyclone separator 2 is equipped with a return pipe at the top that connects to the nitrogen pipe 10, and a nitrogen filter 9 is installed on the return pipe; the second-stage sieve plate separator 3 is equipped with a sight glass 302 on the upper side wall, a pressure gauge 21 at the top, and a branch at the bottom that connects to the gas delivery pipe 19.
[0037] The top of the gas-liquid separator 5 is provided with a branch line for returning to the reduction tank 1. The branch line is equipped with a return hydrogen regulating valve 24 and a circulation pump 27. A level gauge 502 is installed at the bottom, and the bottom is connected to the sewage discharge pipe 22. The top of the gas-liquid separator 5 is also connected to the gas delivery pipe 19.
[0038] The operation process of the above-mentioned device is as follows:
[0039] Catalyst feeding and pretreatment: Nitrogen from nitrogen pipeline 10 pressurizes the deactivated catalyst slurry from settling tank 7 into filter tank 6. In filter tank 6, the catalyst solid and residual amination liquid are initially separated. The separated waste liquid is discharged through drain pipeline 13 and can be introduced into the amination liquid treatment system for purification. The catalyst after initial separation is transported to reduction tank 1. When the amount of catalyst used is insufficient to meet the amination reaction requirements due to catalyst wear, fresh catalyst can be added through fresh catalyst injection pipeline 12.
[0040] Catalyst activation and reduction: In reduction tank 1, nitrogen purging is performed first. The purging nitrogen is sent out through gas delivery pipeline 19. After purging, hydrogen is introduced through the bottom gas distribution plate 16 controlled by hydrogen inlet regulating valve 25. At the same time, stirring device 15 is started to disperse bubbles and promote full gas-solid contact for catalyst reduction and activation reaction. During the reduction process, the gas (mainly containing nitrogen, hydrogen, moisture and a small amount of fine powder) coming out from the top of reduction tank 1 enters the tail gas treatment unit. The gas passes through tail gas filter 8 to remove residual fine powder, condenser 4 to cool and condense, and then enters gas-liquid separator 5. The mist droplets are further captured by wire mesh demister 501. Liquid level gauge 502 is used to monitor the condensate level. When the liquid level no longer increases, the reduction is complete. At this time, the pipeline connected to the tail gas treatment unit is closed. The hydrogen inlet regulating valve 25 on the hydrogen pipeline is closed to block the hydrogen supply. The condensate is discharged through the drain pipe 22 at the bottom. The gas produced during the treatment process can be returned to the reduction tank 1 for recycling through the reflux hydrogen regulating valve 24 at the top. After the hydrogen reflux is formed, the tail gas can be sampled and detected by monitoring the circulation or the liquid level of the level gauge 502 can be monitored. The opening of the hydrogen inlet regulating valve 25 can be adjusted appropriately to maintain a suitable hydrogen concentration in the reduction system. In the tail gas treatment unit, the circulating water first enters the jacket of the gas-liquid separator 5 through the circulating water inlet pipe 17, then flows into the shell side of the condenser 4 to cool the process gas, and finally is discharged through the circulating water outlet pipe 18 to form a cooling cycle. The reduction tank 1 uses heat transfer oil as a heat source to provide the heat required for the reduction process.
[0041] After reduction, before the catalyst enters the separation unit, the reaction unit is purged with nitrogen. The purging exhaust gas is sent out through the gas delivery pipeline 19. Then, the nitrogen inlet regulating valve A is opened, and the pressure in the reduction tank 1 is controlled by the pressure sensor in the pressure relief valve group. The catalyst is forced from the bottom of the reduction tank 1 into the first-stage cyclone separator for separation. The pressure relief valve group 14 at the top of the reduction tank 1 is used to control the system pressure. When the pressure is over-pressurized, it is automatically released and sent out through the gas delivery pipeline 19 to ensure safety.
[0042] Catalyst fine screening and recovery: In the primary cyclone separator 2, most catalyst particles are separated. Nitrogen is introduced into the primary cyclone separator 2 through the nitrogen pipeline 10 to enhance the separation effect. The separated catalyst particles enter the downstream secondary sieve plate separator 3. The sieve 301 (70 mesh) inside the secondary sieve plate separator 3 screens the catalyst. Catalyst particles of the qualified size accumulate at the bottom and can be transported to the amination reactor for reuse through the catalyst external pipeline 20 under the pressure of nitrogen (controlled by the nitrogen inlet regulating valve B26). Large particles can be periodically discharged, crushed, and reactivated. The sight glass 302 is used to observe the internal conditions, and the pressure gauge 21 is used to monitor the pressure. The exhaust gas generated in the primary cyclone separator 2 is filtered by the nitrogen filter 9 and can be returned to the primary cyclone separator 2 for continued recycling.
Claims
1. A catalyst recovery and treatment device for tertiary amine production, characterized in that, It includes an activation unit, a separation unit, and an exhaust gas treatment unit connected in sequence to the activation unit; The activation unit includes a reduction tank (1), the top of which is connected to a nitrogen pipeline (10) and a fresh catalyst injection pipeline (12), and the lower sidewall is connected to a hydrogen pipeline (11). The exhaust gas treatment unit includes an exhaust gas filter (8), a condenser (4), and a gas-liquid separator (5) connected in sequence; The separation unit includes a primary cyclone separator (2) and a secondary sieve plate separator (3) connected in sequence; the top of the primary cyclone separator (2) is connected to the bottom of the reduction tank (1) through a feed pipe on the top side wall, and the side wall is provided with an air inlet connected to the nitrogen pipeline (10); the secondary sieve plate separator (3) is provided with a screen (301) inside, and the bottom is connected to the catalyst delivery pipeline (20).
2. The catalyst recovery and treatment device for tertiary amine production according to claim 1, characterized in that, The reduction tank (1) is connected to the settling tank (7) through the filter tank (6). The top of the settling tank (7) is connected to the nitrogen pipeline (10), and the bottom of the filter tank (6) is connected to the drain pipeline (13). An inclined filter baffle is installed inside the filter tank (6).
3. The catalyst recovery and treatment device for tertiary amine production according to claim 1, characterized in that, The nitrogen pipeline (10) is equipped with a nitrogen inlet regulating valve A (23) on the section of the pipeline before it is connected to the reduction tank (1), and the hydrogen pipeline (11) is equipped with a hydrogen inlet regulating valve (25).
4. The catalyst recovery and treatment device for tertiary amine production according to claim 1, characterized in that, The bottom of the reduction tank (1) is provided with an air distribution plate (16), and the air distribution plate (16) is provided with an oblique hole (1601). The reduction tank (1) is equipped with a stirring device (15), and the blades of the stirring device (15) are a bottom anchor type combined with an upper propeller.
5. The catalyst recovery and treatment device for tertiary amine production according to claim 1, characterized in that, The gas-liquid separator (5) has a jacket structure with a built-in wire mesh demister (501). The jacket of the gas-liquid separator (5) is connected to the circulating water input pipeline (17). The bottom of the jacket is provided with a pipeline connected to the shell side of the condenser (4). The top of the shell side of the condenser (4) is connected to the circulating water output pipeline (18).
6. The catalyst recovery and treatment device for tertiary amine production according to claim 1, characterized in that, The top of the primary cyclone separator (2) is equipped with a return pipe connected to the nitrogen pipe (10), and a nitrogen filter (9) is installed on the return pipe.
7. The catalyst recovery and treatment device for tertiary amine production according to claim 1, characterized in that, The secondary sieve plate separator (3) is equipped with a sight glass (302) on the upper side wall, a pressure gauge (21) on the top, and a branch line connected to the gas delivery pipeline (19) at the bottom.
8. The catalyst recovery and treatment device for tertiary amine production according to claim 1, characterized in that, The nitrogen pipeline (10) is also provided with a branch connected to the secondary sieve plate separator (3), and a nitrogen inlet regulating valve B (26) is provided on the branch.
9. The catalyst recovery and treatment device for tertiary amine production according to claim 7, characterized in that, The gas-liquid separator (5) has a branch line at the top that returns to the reduction tank (1). The branch line is equipped with a return hydrogen regulating valve (24) and a circulation pump (27). A level gauge (502) is installed at the bottom. The bottom is connected to the sewage pipe (22). The top of the gas-liquid separator (5) is connected to the gas delivery pipe (19).
10. The catalyst recovery and treatment device for tertiary amine production according to claim 1, characterized in that, The top of the reduction tank (1) is also equipped with a pressure relief valve assembly (14), which consists of a main pressure relief valve and a pressure sensor. The outlet of the main pressure relief valve is equipped with a pipeline connected to the exhaust gas filter (8).