A recovery system for recovering theophylline sodium from theophylline sodium mother liquor

Abstract

This application relates to a recovery system for recovering sodium theophylline from theophylline mother liquor. The recovery system includes a recovery tower, a rinsing tower, and a temporary storage tank. The inlet of the rinsing tower is connected to one outlet of the recovery tower, and the inlet of the temporary storage tank is connected to the outlet of the rinsing tower. Suspended resin balls in the recovery tower are rinsed in the rinsing tower and then stored in the temporary storage tank before being fed back into the recovery tower. The recovery system for recovering sodium theophylline from theophylline mother liquor disclosed in this application improves the utilization rate and adsorption effect of the adsorbent material by circulating it, and ensures the continuous operation of the adsorption process through off-site regeneration.

Description

Technical Field

[0001] This application relates to the field of chemical production technology, and in particular to a recovery system for recovering sodium theophylline from sodium theophylline mother liquor. Background Technology

[0002] Theophylline sodium is an important intermediate in caffeine production. A commonly used production process is to use chloroacetic acid as the starting material, and then proceed through neutralization-cyanation-acidification-condensation-cyclization-nitrosation-reduction-acylation-ring closure-centrifugation to obtain solid theophylline sodium for use in the next step of the methylation process. The centrifugation mother liquor contains 0.5%-0.7% theophylline sodium.

[0003] Theophylline sodium is an organic compound that is slightly soluble in water. During the synthesis of theophylline or theophylline sodium, a certain amount of chemical mother liquor is generated. The mother liquor contains trace amounts of theophylline sodium, which has long placed a great burden and difficulty on wastewater treatment.

[0004] The traditional techniques for extracting sodium theophylline or theophylline from sodium theophylline or theophylline mother liquor mainly include the following:

[0005] The evaporation crystallization method involves heating the mother liquor to evaporate the water, thereby increasing the concentration of organic matter in the residual mother liquor. After cooling, crystallization, and centrifugation, crude theophylline sodium or crude theophylline is obtained. The problems with this process are high energy consumption and an increased content of various impurities in the residual mother liquor, resulting in a high impurity content in the recovered crude theophylline sodium or crude theophylline.

[0006] Solvent extraction requires the use of organic solvents such as octanol as extractants. These extractants are volatile and have a certain degree of toxicity. At the same time, organic solvents such as octanol have a certain solubility in the aqueous phase, and some octanol and theophylline remain in the raffinate, resulting in the loss of the target analyte.

[0007] The resin particle adsorption method uses resin particles to adsorb target substances in the mother liquor. However, in large-scale applications, it has been found that the resin particles in the adsorption tower have problems such as uneven adsorption and difficulty in regeneration. Summary of the Invention

[0008] This application provides a recovery system for recovering sodium theophylline from theophylline mother liquor. The system improves the utilization rate and adsorption effect of the adsorbent by circulating the adsorbent material, and ensures the continuous operation of the adsorption process by off-site regeneration.

[0009] The above-mentioned objective of this application is achieved through the following technical solution:

[0010] This application provides a recovery system for recovering sodium theophylline from sodium theophylline mother liquor, comprising:

[0011] Recycling tower;

[0012] A flushing tower, the input of which is connected to one output of a recovery tower; and

[0013] A temporary storage tank, the input of which is connected to the output of the flushing tower;

[0014] The suspended resin balls in the recovery tower are rinsed in the flushing tower and then stored in the temporary storage tank before being fed back into the recovery tower.

[0015] In one possible implementation of this application, the adsorption tower includes:

[0016] Adsorption tower;

[0017] Multiple isolation hoods are arranged sequentially from top to bottom inside the adsorption tower, with a distance between adjacent isolation hoods. The cross-sectional area of ​​the isolation hoods tends to decrease in the direction away from the bottom of the adsorption tower.

[0018] Permeation holes are evenly distributed on the isolation cover;

[0019] Suspended resin balls are filled in the lower area of ​​each isolation shield, and the diameter of the suspended resin balls is larger than the diameter of the permeation holes;

[0020] The passageway is located at the top of the isolation enclosure; and

[0021] An openable valve is installed on the adsorption tower, and the openable valve is configured to have open and close channels.

[0022] In one possible implementation of this application, the suspended resin ball includes:

[0023] outer shell;

[0024] Through holes are evenly distributed on the outer casing;

[0025] Adsorbed resin particles are filled into the outer shell; and

[0026] The buoyancy body is located inside the outer shell;

[0027] The sum of the volumes of the adsorbed resin particles and the buoyancy body is less than the volume of the internal space of the outer shell.

[0028] In one possible implementation of this application, the sum of the volumes of the adsorbed resin particles and the buoyancy body is 60%-80% of the internal space volume of the outer shell.

[0029] In one possible implementation of this application, the outer shell is made of absorbent resin.

[0030] In one possible implementation of this application, the openable valve includes:

[0031] The first actuator is located on the outer wall of the adsorption tower;

[0032] The connecting rod, with its first end connected to the first driver; and

[0033] A blind flange is installed on the second end of the connecting rod.

[0034] In one possible implementation of this application, the cross-sectional area of ​​the isolation hood tends to decrease in the direction away from the bottom of the adsorption tower and moves towards the direction closer to the first actuator.

[0035] One possible implementation of this application also includes:

[0036] The telescopic unit is installed on the blind plate, and the working direction of the telescopic unit is not parallel to the moving direction of the blind plate;

[0037] The second actuator is located on the outer wall of the adsorption tower;

[0038] Connect the pipes to connect the telescopic unit and the second driver to the same circuit.

[0039] In one possible implementation of this application, a flexible expander is provided on the piston of the telescopic unit, and the flexible expander is connected to the second actuator.

[0040] In one possible implementation of this application, a guide plate inclined inside the adsorption tower is also included;

[0041] The isolation covers inside the adsorption tower are all located below the guide plate.

[0042] Overall, the recovery system for recovering sodium theophylline from the theophylline mother liquor provided in this application uses a grouped flow of suspended resin balls to adsorb sodium theophylline in the mother liquor. This method allows each group of suspended resin balls to fully adsorb sodium theophylline in the mother liquor, resulting in suspended resin balls with relatively consistent adsorption rates.

[0043] After adsorption, the suspended resin balls are transferred outside the adsorption tower for regeneration. The group regeneration method can effectively control the amount of suspended resin balls regenerated, reducing the concentration of sodium theophylline in the regenerated solution while increasing the concentration of sodium theophylline in the regenerated solution.

[0044] The regenerated suspended resin balls are returned to the lowest point of the adsorption tower. This method of grouping and circulating the suspended resin balls and regenerating them outside the tower allows the adsorption process inside the adsorption tower to proceed continuously. Compared with the method of using two adsorption towers alternately, it has more advantages in terms of equipment investment, floor space and operation and maintenance. Attached Figure Description

[0045] Figure 1This is a structural schematic diagram of a recovery system for recovering sodium theophylline from sodium theophylline mother liquor, as provided in this application.

[0046] Figure 2 This is a schematic diagram illustrating the working principle of a recycling tower provided in this application.

[0047] Figure 3 This is a schematic diagram of the internal structure of a recycling tower provided in this application.

[0048] Figure 4 This is a structural schematic diagram of a suspended resin ball provided in this application.

[0049] Figure 5 This is a structural schematic diagram of an openable valve provided in this application.

[0050] Figure 6 This is a schematic diagram of the position of the blind plate when the channel is open, as provided in this application.

[0051] Figure 7 This is a structural schematic diagram of a telescopic unit, a second actuator, and a connecting pipe provided in this application.

[0052] Figure 8 This is a structural schematic diagram of a telescopic unit with an added flexible expander provided in this application.

[0053] Figure 9 This is a comparative schematic diagram of a flexible expandable body before and after expansion, provided in this application.

[0054] In the diagram, 1. Recovery tower, 2. Flushing tower, 3. Temporary storage tank, 11. Adsorption tower, 12. Isolation hood, 13. Permeation hole, 14. Suspended resin ball, 15. Channel, 16. Opening valve, 17. Guide plate, 141. Outer shell, 142. Through hole, 143. Adsorbent resin particles, 144. Buoyancy body, 161. First actuator, 162. Connecting rod, 163. Blind plate, 164. Telescopic unit, 165. Second actuator, 166. Connecting pipe, 167. Flexible expansion body. Detailed Implementation

[0055] The technical solutions in this application will be further described in detail below with reference to the accompanying drawings.

[0056] This application discloses a recovery system for recovering sodium theophylline from sodium theophylline mother liquor. Please refer to [link to relevant documentation]. Figure 1The recovery system is mainly divided into three parts: recovery tower 1, flushing tower 2 and temporary storage tank 3. The theophylline sodium mother liquor (hereinafter referred to as mother liquor) is adsorbed in the recovery tower 1 using suspended resin balls 14. After adsorption for a period of time, the suspended resin balls 14 in the recovery tower 1 enter the flushing tower 2 for regeneration. After regeneration, the suspended resin balls 14 are sent to the temporary storage tank 3 and returned to the recovery tower 1 when needed.

[0057] Figure 1 The arrows in the diagram indicate the movement trajectory of the suspended resin ball 14.

[0058] Please see Figure 2 The recovery tower 1 consists of an adsorption tower 11, an isolation hood 12, suspended resin balls 14, a channel 15, and an open valve 16. There are multiple isolation hoods 12, which are arranged sequentially from top to bottom inside the adsorption tower 11. There is a distance between any two adjacent isolation hoods 12, and the function of this distance is to accommodate the suspended resin balls 14.

[0059] Please see Figure 3 The adsorption tower 11 has two inlet ends and two outlet ends. The mother liquor to be treated flows in from the inlet end located at the bottom of the adsorption tower 11 and then flows out from the outlet end located at the top of the adsorption tower 11. New or regenerated suspended resin balls 14 flow in from the inlet end located at the bottom of the adsorption tower 11, and the suspended resin balls 14 in a saturated state flow out from the outlet end located at the top of the adsorption tower 11.

[0060] Meanwhile, in the direction away from the bottom of the adsorption tower 11, the cross-sectional area of ​​the isolation cover 12 tends to decrease, that is, the isolation cover 12 has a conical structure. This structure of the isolation cover 12 allows the suspended resin ball 14 located below the isolation cover 12 to move to the highest point of the isolation cover 12 when it floats up, and then pass through the channel 15 on the isolation cover 12.

[0061] The isolation cover 12 is also evenly distributed with permeation holes 13. The function of the permeation holes 13 is to allow the mother liquor to pass through, so that the spaces on both sides of the isolation cover 12 are connected.

[0062] Each isolation shield 12 is filled with a certain number of suspended resin balls 14. The diameter of the suspended resin balls 14 is larger than the diameter of the permeation hole 13, so that the suspended resin balls 14 can pass through the channel 15 at the top of the isolation shield 12.

[0063] An open valve 16 is also installed on the adsorption tower 11. The function of the open valve 16 is to open and close the channel 15. In a specific process, the mother liquor to be treated flows into the adsorption tower 11 and begins to flow from bottom to top. During this process, the mother liquor will sequentially pass through each isolation hood 12 and the suspended resin balls 14 below each isolation hood 12.

[0064] The suspended resin balls 14 adsorb theophylline sodium from the mother liquor. During continuous flow, the theophylline sodium in the mother liquor is gradually adsorbed by the suspended resin balls 14. Finally, the mother liquor flows out from the adsorption tower 11. As the treatment process continues, the amount of theophylline sodium adsorbed by the suspended resin balls 14 gradually increases, at which point it is necessary to move and regenerate the suspended resin balls 14.

[0065] The specific process of movement and regeneration is as follows:

[0066] The topmost open valve 16 opens first, at which point the suspended resin ball 14 below the topmost isolation cover 12 moves above the isolation cover 12, and the water flow removes this part of the suspended resin ball 14 from the adsorption tower 11.

[0067] Next, in a top-down direction, the open valves 16 on each isolation shield 12 are opened sequentially. It should be noted that when all the suspended resin balls 14 below an isolation shield 12 have moved into the space above the isolation shield 12, the open valve 16 belonging to that isolation shield 12 is closed, and then the next open valve 16 is opened.

[0068] Here, the space under each isolation cover 12 is regarded as an independent space. A group of suspended resin balls 14 (located under the same isolation cover 12) will pass through each independent space in sequence and then be removed from the adsorption tower 11.

[0069] It should be understood that in a recovery tower that combines adsorption and regeneration, the mother liquor flows from bottom to top. When the adsorption resin at the bottom can no longer adsorb (saturated state), the adsorption resin at the top is in an unsaturated state.

[0070] However, during the regeneration process, the solution in the recovery tower does flow from top to bottom. That is, the adsorption resin at the top will be regenerated first, while the adsorption resin at the bottom, which should be regenerated first, is relegated to the back of the sequence.

[0071] To address the aforementioned issues and ensure the regeneration process proceeds smoothly, the adsorption resin needs to be soaked for an extended period, or two recovery towers need to be used alternately. While this approach solves the regeneration problem to some extent, it generates a significant amount of regeneration solution due to repeated rinsing. The regeneration solution obtained using this method still exhibits a low concentration of sodium theophylline, necessitating more costly extraction.

[0072] The recovery system for recovering sodium theophylline from the theophylline mother liquor provided in this application uses a moving suspended resin ball 14 to absorb the theophylline in the mother liquor. The isolation cover 12 in the adsorption tower 11 divides the suspended resin ball 14 into multiple groups, and each group of suspended resin balls 14 moves from bottom to top in the adsorption tower 11.

[0073] After adsorbing a higher concentration of mother liquor, the suspended resin balls 14 located at the bottom will move upwards to the area containing a lower concentration of mother liquor. This method allows each group of suspended resin balls 14 to adsorb theophylline sodium from the mother liquor as much as possible.

[0074] After passing through multiple isolation chambers 12, the suspended resin balls 14 are removed from the adsorption tower 11, and then these suspended resin balls 14 removed from the adsorption tower 11 are regenerated. This regeneration has several advantages:

[0075] 1. The number of suspended resin balls 14 is reduced;

[0076] 2. The adsorption capacity of the suspended resin balls 14 is relatively uniform;

[0077] 3. The regeneration process of the suspended resin balls 14 will not delay the treatment of the mother liquor in the adsorption tower 11.

[0078] After a set of suspended resin balls 14 is removed from the adsorption tower 11, a new set of suspended resin balls 14 is added to the adsorption tower 11. The new set of suspended resin balls 14 is located at the bottom of the adsorption tower 11, where the concentration of sodium theophylline in the mother liquor is the highest. Using this new set of suspended resin balls 14 can achieve a better adsorption effect.

[0079] Overall, the recovery system for recovering sodium theophylline from the theophylline mother liquor provided in this application uses a grouped circulation method of suspended resin balls 14 to adsorb sodium theophylline in the mother liquor. This method can ensure that each group of suspended resin balls 14 can fully adsorb sodium theophylline in the mother liquor, resulting in suspended resin balls 14 with relatively consistent adsorption rates.

[0080] The suspended resin balls 14 that have completed adsorption are transferred to the outside of the adsorption tower 11 for regeneration. The group regeneration method can effectively control the amount of suspended resin balls 14 regenerated, and can increase the concentration of theophylline sodium in the regenerated solution while reducing the amount of regenerated solution.

[0081] The regenerated suspended resin balls 14 are returned to the lowest point of the adsorption tower 11. This method of grouping and circulating the suspended resin balls 14 and regenerating them outside the tower allows the adsorption process inside the adsorption tower 11 to proceed continuously. Compared with the method of alternating use of two adsorption towers 11, it has more advantages in terms of equipment investment, floor space and operation and maintenance.

[0082] Please see Figure 4 In some examples, the suspended resin ball 14 is composed of an outer shell 141, adsorbent resin particles 143 and buoyancy body 144, etc. The surface of the outer shell 141 is evenly distributed with through holes 142, and the function of the through holes 142 is to connect the space outside the outer shell 141 with the space inside the outer shell 141.

[0083] Both the adsorbent resin particles 143 and the buoyancy body 144 are located inside the outer shell 141. The function of the adsorbent resin particles 143 is to adsorb theophylline sodium in the mother liquor, and the function of the buoyancy body 144 is to provide buoyancy so that the suspended resin ball 14 can float in the mother liquor.

[0084] The sum of the volumes of the adsorbent resin particles 143 and the buoyancy body 144 is less than the volume of the internal space of the outer shell 141. The purpose is to reserve some space so that the adsorbent resin particles 143 can have sufficient contact with the mother liquor.

[0085] In some possible implementations, the sum of the volumes of the adsorbed resin particles 143 and the buoyancy body 144 is 60%-80% of the internal space volume of the outer shell 141.

[0086] In some possible implementations, the outer shell 141 is made of absorbent resin.

[0087] Please see Figure 5 and Figure 6 In some examples, the openable valve 16 is composed of a first actuator 161, a connecting rod 162, and a blind plate 163. The first actuator 161 is fixedly installed on the outer wall of the adsorption tower 11. The first end of the connecting rod 162 is connected to the first actuator 161, and the second end is connected to the blind plate 163. When the first actuator 161 is activated, it can drive the blind plate 163 to move linearly back and forth through the connecting rod 162.

[0088] When the blind plate 163 moves linearly back and forth, it can open and close the channel 15.

[0089] In some possible implementations, the cross-sectional area of ​​the isolation shroud 12 tends to decrease in the direction away from the bottom of the adsorption tower 11 and moves towards the first actuator 161. This helps to shorten the length of the connecting rod 162.

[0090] Please see Figure 7 Furthermore, a telescopic unit 164, a second actuator 165, and a connecting pipe 166 are added. The telescopic unit 164 is fixedly installed on the blind plate 163. The working direction of the telescopic unit 164 is not parallel to the moving direction of the blind plate 163. That is to say, the piston of the telescopic unit 164 can extend into the channel 15.

[0091] In some possible implementations, the working direction of the telescopic unit 164 is perpendicular to the moving direction of the blind plate 163.

[0092] The function of the telescopic unit 164 is to prevent the suspended resin balls 14 from accumulating in the channel 15 and causing channel blockage. The telescopic unit 164 is driven by the second actuator 165, which is installed on the outer wall of the adsorption tower 11 and connected to the telescopic unit 164 through the connecting pipe 166. The connecting pipe 166 connects the telescopic unit 164 and the second actuator 165 in the same circuit.

[0093] In some possible implementations, the telescopic unit 164 uses a cylinder, and the second actuator 165 uses a compressor. The compressed air generated by the compressor is delivered to the telescopic unit 164 through the connecting pipe 166 to drive the piston of the telescopic unit 164 to extend and retract.

[0094] Please see Figure 8 Furthermore, a flexible expander 167 is added to the piston of the telescopic unit 164. The flexible expander 167 is connected to the second driver 165 and can switch between an expanded state and a non-expanded state under the drive of the second driver 165.

[0095] It should be understood that the diameter of the piston in the telescopic unit 164 is limited. By adding the flexible expander 167, the volume of the flexible expander 167 can be increased, such as... Figure 9 As shown, the blocked passage 15 is cleared by pushing.

[0096] Please see Figure 3 In some examples, the guide plate 17 is inclinedly installed inside the adsorption tower 11, and the guide plate 17 is located at the highest point inside the adsorption tower 11, that is, the isolation cover 12 inside the adsorption tower 11 is located below the guide plate 17. The function of the guide plate 17 is to guide the suspended resin balls 14 out of the adsorption tower 11.

[0097] Specifically, when the uppermost group of suspended resin balls 14 in the adsorption tower 11 moves to the guide plate 17, it will move along the inclined guide plate 17 to the highest point of the guide plate 17. The outflow pipe of the adsorption tower 11 is also located at this point, and under the push of the mother liquor, these suspended resin balls 14 will automatically flow into the outflow pipe of the adsorption tower 11.

[0098] The embodiments described in this specific implementation are 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 recovery system for recovering sodium theophylline from sodium theophylline mother liquor, characterized in that, include: Recycling tower (1); The flushing tower (2) is connected to one of the output ends of the recovery tower (1); Temporary storage tank (3), the input end of which is connected to the output end of flushing tower (2); The suspended resin balls (14) in the recovery tower (1) are rinsed in the flushing tower (2) and then stored in the temporary storage tank (3) before being fed back into the recovery tower (1). The recycling tower (1) includes: Adsorption tower (11); Multiple isolation hoods (12) are arranged sequentially from top to bottom inside the adsorption tower (11). There is a distance between adjacent isolation hoods (12). In the direction away from the bottom of the adsorption tower (11), the cross-sectional area of ​​the isolation hood (12) tends to decrease. Permeation holes (13) are evenly distributed on the isolation cover (12); Suspended resin balls (14) are filled in the area below each isolation shield (12), and the diameter of the suspended resin balls (14) is larger than the diameter of the permeation holes (13). The passage (15) is located at the top of the isolation enclosure (12); An open valve (16) is provided on the adsorption tower (11), and the open valve (16) is configured to open and close the channel (15). It also includes a guide plate (17) inclined inside the adsorption tower (11), and the isolation cover (12) inside the adsorption tower (11) is located below the guide plate (17); In this process, the suspended resin balls (14) move from bottom to top in the adsorption tower (11). After adsorbing a higher concentration of mother liquor, the suspended resin balls (14) located below the adsorption tower (11) will move upward to the area of ​​a lower concentration of mother liquor and then be removed from the adsorption tower (11) for regeneration. The suspended resin balls (14) in the adsorption tower (11) are divided into multiple groups. After one group of suspended resin balls (14) is removed from the adsorption tower (11), a new group of suspended resin balls (14) will be added to the adsorption tower (11). This group of suspended resin balls (14) is located in the lowest region of the adsorption tower (11).

2. The recovery system for recovering sodium theophylline from the theophylline mother liquor according to claim 1, characterized in that, The suspended resin balls (14) include: Outer shell (141); Through holes (142) are evenly distributed on the outer shell (141); Adsorbed resin particles (143) are filled inside the outer casing (141); and A buoyancy body (144) is disposed inside the outer shell (141); The sum of the volumes of the adsorbed resin particles (143) and the buoyancy body (144) is less than the volume of the internal space of the outer shell (141).

3. The recovery system for recovering sodium theophylline from the theophylline mother liquor according to claim 2, characterized in that, The sum of the volumes of the adsorbed resin particles (143) and the buoyancy body (144) is 60%-80% of the internal space volume of the outer shell (141).

4. The recovery system for recovering sodium theophylline from the theophylline mother liquor according to claim 2 or 3, characterized in that, The outer shell (141) is made of adsorption resin.

5. The recovery system for recovering sodium theophylline from the theophylline mother liquor according to claim 1, characterized in that, Open valve (16) includes: The first actuator (161) is located on the outer wall of the adsorption tower (11); Link (162), the first end of which is connected to the first driver (161); and A blind plate (163) is provided on the second end of the connecting rod (162).

6. The recovery system for recovering sodium theophylline from the theophylline mother liquor according to claim 5, characterized in that, In the direction away from the bottom of the adsorption tower (11), the cross-sectional area of ​​the isolation cover (12) tends to decrease and moves toward the first actuator (161).

7. The recovery system for recovering sodium theophylline from the theophylline mother liquor according to claim 5, characterized in that, Also includes: The telescopic unit (164) is mounted on the blind plate (163), and the working direction of the telescopic unit (164) is not parallel to the moving direction of the blind plate (163); The second actuator (165) is located on the outer wall of the adsorption tower (11); Connect the pipe (166) to connect the telescopic unit (164) and the second driver (165) to the same circuit.

8. The recovery system for recovering sodium theophylline from the theophylline mother liquor according to claim 7, characterized in that, The piston of the telescopic unit (164) is provided with a flexible expansion body (167), which is connected to the second driver (165).

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