Device for preparing carboxylic ester

Abstract

The utility model discloses a device for preparing carboxylic ester. The device at least comprises a reactor; the purification equipment is connected with the reactor; the at least one separation tank is arranged on one side, far away from the reactor, of the purification equipment; the sewage collection tank is connected with one side, far away from the purification equipment, of the separation tank; the at least one buffer tank is arranged on one side, far away from the separation tank, of the sewage collection tank; the sewage stripping tower is arranged on one side, far away from the sewage collecting tank, of the buffer tank; the aldehyde rectifying tower is connected with the sewage stripping tower; and the connecting pipeline is used for connecting adjacent equipment. According to the device for preparing the carboxylic ester, provided by the utility model, the treatment load of a sewage treatment plant can be reduced, bacteria in a sewage treatment system are not damaged, aldehyde substances in aldehyde-containing sewage are recycled, and the economic benefit is increased.

Description

Technical Field

[0001] The utility model relates to the technical field of carboxylic acid ester preparation, in particular to a device for preparing carboxylic acid ester. Background Art

[0002] Carboxylic acid ester compounds are important intermediate products or end products in the production of chemicals and are widely used in the fields of spices, flavors, cosmetics, soaps, plastics, pharmaceutical synthesis and industrial solvents. Due to the existence of side reactions, aldehyde-containing wastewater is inevitably produced during the preparation of carboxylic acid esters, and the aldehyde-containing wastewater is generally sent directly to the sewage treatment plant. Therefore, the current device for preparing carboxylic acid esters has the problems of increasing the load of the sewage treatment plant, killing bacteria in the sewage treatment system, destroying the treatment effect of the sewage treatment plant and wasting aldehyde substances. Utility Model Content

[0003] The utility model aims to provide a device for preparing carboxylic acid esters, which can reduce the processing load of sewage treatment plants, does not destroy bacteria in sewage treatment systems, recovers aldehyde substances in aldehyde-containing sewage, and increases economic benefits.

[0004] In order to achieve the above-mentioned purpose and other related purposes, the utility model is implemented through the following technical solutions.

[0005] The utility model provides a device for preparing carboxylic acid ester, which at least comprises:

[0006] Reactor;

[0007] A purification device connected to the reactor;

[0008] at least one separation tank, disposed on a side of the purification device away from the reactor;

[0009] A sewage collection tank connected to a side of the separation tank away from the purification device;

[0010] At least one buffer tank is arranged on a side of the sewage collection tank away from the separation tank;

[0011] A sewage stripping tower is arranged on a side of the buffer tank away from the sewage collecting tank;

[0012] an aldehyde distillation tower connected to the sewage stripping tower; and

[0013] Connect pipes and adjacent equipment.

[0014] In an embodiment of the utility model, the device further comprises a sewage delivery pump, and the sewage delivery pump is arranged between the sewage collection tank and the buffer tank.

[0015] In one embodiment of the utility model, when there is one buffer tank, the buffer tank is arranged between the sewage delivery pump and the sewage stripping tower.

[0016] In an embodiment of the present invention, when there are multiple buffer tanks, the multiple buffer tanks are arranged on a side of the sewage delivery pump away from the sewage collection tank, and the multiple buffer tanks are connected in parallel.

[0017] In one embodiment of the utility model, when there is one separation tank, one separation tank is arranged between the purification equipment and the sewage collection tank.

[0018] In one embodiment of the utility model, when there are multiple separation tanks, the multiple separation tanks are arranged between the purification equipment and the sewage collection tank, and the multiple separation tanks are connected in parallel.

[0019] In one embodiment of the utility model, the device further comprises a first reboiler, and the first reboiler is arranged at one end of the sewage stripping tower.

[0020] In one embodiment of the present invention, the aldehyde distillation tower is connected to an end of the sewage stripping tower away from the first reboiler.

[0021] In one embodiment of the utility model, the device further comprises a sewage discharge pipe, and the sewage discharge pipe is connected to one end of the sewage stripping tower close to the first reboiler.

[0022] In one embodiment of the present invention, the device further comprises a second reboiler, and the second reboiler is arranged at one end of the aldehyde distillation tower.

[0023] In summary, the utility model provides a device for preparing carboxylic acid esters, which can recover aldehyde substances in aldehyde-containing sewage, avoid waste, and increase economic benefits. Moreover, the device provided by the utility model can greatly reduce the load of the sewage treatment plant, does not destroy the bacteria in the sewage treatment system, and ensures the normal operation of the sewage treatment plant.

[0024] Of course, any method of implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1The present invention is a schematic structural diagram of a device for preparing carboxylic acid esters in one embodiment of the present invention.

[0027] Marking Description:

[0028] 11. Reactor; 12. Purification equipment; 13. Separation tank; 14. Sewage collection tank; 15. Sewage delivery pump; 16. Buffer tank; 17. Sewage stripping tower; 181. First reboiler; 182. Second reboiler; 19. Aldehyde distillation tower; 20. Connecting pipes; 21. Sewage discharge pipe. DETAILED DESCRIPTION

[0029] The following describes the implementation of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations. The details in the present invention can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0030] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed at will, and the component layout may also be more complicated.

[0031] In the present invention, it should be noted that, if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, if the terms "first" and "second" appear, they are only used for description and distinction purposes, and cannot be understood as indicating or implying relative importance.

[0032] In the process of preparing carboxylic acid esters, it is inevitable to produce aldehyde-containing wastewater. The chemical oxygen demand (COD) value of aldehyde-containing wastewater is above 30,000 mg / L, which far exceeds the tolerance of bacteria in the sewage treatment system. Therefore, if the aldehyde-containing wastewater is directly discharged to the sewage treatment plant, while increasing the processing load of the sewage treatment plant, it will also kill the bacteria in the sewage treatment system, affecting the normal operation of the sewage treatment plant. The device for preparing carboxylic acid esters provided by the utility model can reduce the COD value of aldehyde-containing wastewater to below 600 mg / L through treatment, and can recover aldehyde substances in aldehyde-containing wastewater, greatly reducing the processing load of the sewage treatment plant, not destroying the bacteria in the sewage treatment system, and ensuring the normal operation of the sewage treatment plant. Moreover, the device provided by the utility model recovers aldehyde substances in aldehyde-containing wastewater as products for sale, which can increase economic benefits and avoid waste.

[0033] See also Figure 1 As shown, the utility model provides a device for preparing carboxylic acid esters, for example, including a reactor 11, a purification device 12, a separation tank 13, a sewage collection tank 14, a buffer tank 16, a sewage stripping tower 17 and an aldehyde distillation tower 19. Among them, a separation tank 13, a sewage collection tank 14 and a buffer tank 16 are arranged between the sewage stripping tower 17 and the purification device 12, the sewage collection tank 14 is arranged between the buffer tank 16 and the separation tank 13, the buffer tank 16 is arranged between the sewage stripping tower 17 and the sewage collection tank 14, and the aldehyde distillation tower 19 is connected to the sewage stripping tower 17. The device for preparing carboxylic acid esters provided by the utility model can recover aldehyde substances in aldehyde-containing sewage as products by arranging the sewage stripping tower 17 and the aldehyde distillation tower 19, thereby increasing economic benefits. Moreover, the device provided by the utility model recovers aldehyde substances in aldehyde-containing sewage and then sends them to the sewage treatment plant, which can reduce the COD value of aldehyde-containing sewage, prevent bacteria in the sewage treatment system from being destroyed, and ensure the normal operation of the sewage treatment plant.

[0034] See also Figure 1 As shown, in one embodiment of the utility model, the reactor 11 provides a place for the reaction between the raw materials. The raw materials include, for example, ethylene, carboxylic acid, oxygen and catalyst, etc. The catalyst includes, for example, at least one of a liquid acid catalyst, a molecular sieve and a silicon aluminum oxide catalyst, an ion exchange resin catalyst and a heteropolyacid catalyst, etc. The reactor 11 is, for example, a tubular reactor, a kettle reactor or a tower reactor. In the reactor 11, due to the catalytic action of the catalyst, ethylene and carboxylic acid undergo addition esterification. Specifically, ethylene undergoes hydration reaction to generate ethanol, and the generated ethanol continues to undergo esterification reaction with carboxylic acid to generate carboxylic acid ester. However, due to the side reactions between the raw materials, the synthetic product at the outlet of the reactor 11 includes substances such as aldehydes, water and alcohols in addition to carboxylic acid esters.

[0035] See also Figure 1 As shown, in one embodiment of the present invention, the purification device 12 is connected to the reactor 11 for purifying the carboxylic acid ester in the synthetic product. In this embodiment, the synthetic product at the outlet of the reactor 11 enters the purification device 12 for separation, and the carboxylic acid ester product and the aldehyde-containing wastewater are separated according to the physical property difference between the carboxylic acid ester and the by-product. Among them, the purification device 12 includes, for example, a plate distillation tower or a packed distillation tower, and the present invention does not limit the type of the purification device 12.

[0036] See also Figure 1 As shown, in one embodiment of the utility model, a separation tank 13 is arranged on a side of the purification equipment 12 away from the reactor 11. Among them, there is, for example, at least one separation tank 13. In this embodiment, there is, for example, one separation tank 13. After the reaction product of the reactor 11 is purified and separated into the carboxylic acid ester product by the purification equipment 12, the aldehyde-containing wastewater enters the separation tank 13 for separation. By utilizing the solubility difference, the separation tank 13 separates the water-insoluble organic matter in the aldehyde-containing wastewater, thereby increasing the content of aldehyde substances in the aldehyde-containing wastewater, so as to obtain aldehyde substances with qualified purity in the subsequent aldehyde distillation tower 19. In other embodiments of the utility model, there are, for example, multiple separation tanks 13, and multiple separation tanks 13 are arranged between the purification equipment 12 and the wastewater collection tank 14, and multiple separation tanks 13 are connected in parallel to improve the separation efficiency.

[0037] See also Figure 1 As shown, in one embodiment of the utility model, the sewage collection tank 14 is connected to the side of the separation tank 13 away from the purification equipment 12, that is, the separation tank 13 is arranged between the purification equipment 12 and the sewage collection tank 14. In this embodiment, a buffer tank 16 is arranged on the side of the sewage collection tank 14 away from the separation tank 13, and a sewage delivery pump 15 is also arranged between the sewage collection tank 14 and the buffer tank 16. The aldehyde-containing sewage enters the sewage collection tank 14 from the separation tank 13. The sewage collection tank 14 is used to store the aldehyde-containing sewage. The aldehyde-containing sewage in the sewage collection tank 14 is pressurized by the sewage delivery pump 15 and then delivered to the buffer tank 16. If the sewage collection tank 14 is not arranged, once there is no aldehyde-containing sewage in the connecting pipe 20 between the separation tank 13 and the sewage delivery pump 15, it will immediately affect the normal operation of the sewage delivery pump 15 and damage the sewage delivery pump 15. By setting the sewage collecting tank 14 between the separation tank 13 and the sewage delivery pump 15, when there is no formaldehyde-containing sewage in the connecting pipe 20 between the separation tank 13 and the sewage collecting tank 14, the formaldehyde-containing sewage stored in the sewage collecting tank 14 can support the normal operation of the sewage delivery pump 15 for a period of time, leaving the operator with more reaction time to normally stop the sewage delivery pump 15, thereby protecting the sewage delivery pump 15.

[0038] See also Figure 1As shown, in one embodiment of the utility model, the sewage delivery pump 15 is arranged between the sewage collection tank 14 and the buffer tank 16 to increase the pressure of the aldehyde-containing sewage in the connecting pipe 20, so that the aldehyde-containing sewage can smoothly flow into the subsequent buffer tank 16, the sewage stripping tower 17 and the aldehyde distillation tower 19. The sewage delivery pump 15 is, for example, a centrifugal pump, a gear pump, a reciprocating pump, a piston pump or a diaphragm pump.

[0039] See also Figure 1 As shown, in one embodiment of the utility model, a buffer tank 16 is arranged on a side of the sewage collection tank 14 away from the separation tank 13. Therein, there is, for example, at least one buffer tank 16, and the buffer tank 16 is, for example, a diaphragm buffer tank or an airbag buffer tank. In the present embodiment, there is, for example, one buffer tank 16. The buffer tank 16 is arranged between the sewage delivery pump 15 and the sewage stripping tower 17. The formaldehyde-containing sewage pressurized by the sewage delivery pump 15 enters the buffer tank 16 to stabilize the pressure of the formaldehyde-containing sewage at the outlet of the sewage delivery pump 15, ensure the feed stability of the sewage stripping tower 17, and maintain the stable operation of the sewage stripping tower 17. In other embodiments of the utility model, there are, for example, multiple buffer tanks 16, and multiple buffer tanks 16 are arranged on a side of the sewage delivery pump 15 away from the sewage collection tank 14, and the multiple buffer tanks 16 are connected in parallel to improve the efficiency of the buffer tank 16 in stabilizing the pressure of the formaldehyde-containing sewage at the outlet of the sewage delivery pump 15.

[0040] See also Figure 1 As shown, in one embodiment of the utility model, the sewage stripping tower 17 is arranged on the side of the buffer tank 16 away from the sewage collection tank 14. Among them, the top temperature of the sewage stripping tower 17 is controlled at 75-85°C, the temperature of the middle section of the sewage stripping tower 17 is controlled at 95-105°C, the bottom temperature of the sewage stripping tower 17 is controlled at 100-110°C, the top pressure of the sewage stripping tower 17 is controlled at 15-20Kpa, and the bottom pressure of the sewage stripping tower 17 is controlled at 20-25Kpa. By controlling the temperature and pressure at different positions in the sewage stripping tower 17, the aldehyde-containing sewage enters the sewage stripping tower 17 from the middle section of the sewage stripping tower 17, and the crude aldehyde product with a low boiling point evaporates from the sewage into a gaseous mixture, and the gaseous mixture flows out from the top of the sewage stripping tower 17. The sewage with a high boiling point is collected at the bottom of the sewage stripping tower 17 and sent to the sewage treatment plant. Compared with directly sending formaldehyde-containing wastewater to a sewage treatment plant, the device provided by the utility model recovers the aldehyde substances in the formaldehyde-containing wastewater and then sends the wastewater to the sewage treatment plant. While reducing the processing load of the sewage treatment plant, it can also reduce the COD value of the sewage, does not destroy the bacteria in the sewage treatment system, and ensures the normal operation of the sewage treatment plant.

[0041] See also Figure 1As shown, in one embodiment of the utility model, the first reboiler 181 is arranged at one end of the sewage stripping tower 17. In this embodiment, the first reboiler 181 is, for example, arranged at the bottom of the sewage stripping tower 17, and is used to provide heat for the sewage stripping tower 17 so that the low-boiling-point substances in the aldehyde-containing sewage can be evaporated. The first reboiler 181 is, for example, a jacketed reboiler, an internal circulation reboiler, or an external circulation reboiler, and the heat source of the first reboiler 181 is, for example, steam or electric heating.

[0042] See also Figure 1 As shown, in one embodiment of the utility model, the sewage discharge pipe 21 is connected to one end of the sewage stripping tower 17 near the first reboiler 181. In this embodiment, the sewage discharge pipe 21 is connected to the bottom of the sewage stripping tower 17, for example. The aldehyde-containing sewage enters the sewage stripping tower 17, and the crude aldehyde product with a low boiling point evaporates from the sewage into a gaseous mixture, and the gaseous mixture flows out from the top of the sewage stripping tower 17. The sewage with a high boiling point is collected at the bottom of the sewage stripping tower 17 and sent to the sewage treatment plant through the sewage discharge pipe 21.

[0043] See also Figure 1 As shown, in one embodiment of the utility model, the aldehyde distillation tower 19 is connected to the sewage stripping tower 17. The aldehyde distillation tower 19 is, for example, connected to one end of the sewage stripping tower 17 away from the first reboiler 181. The crude aldehyde product evaporated from the aldehyde-containing sewage enters the aldehyde distillation tower 19 from the top of the sewage stripping tower 17. The aldehyde distillation tower 19 separates and purifies the crude aldehyde product according to the difference in boiling points, and the low-boiling-point aldehyde product flows into the aldehyde product tank from the top of the aldehyde distillation tower 19. Impurities with high boiling points in the crude aldehyde product flow into the waste liquid tank from the bottom of the aldehyde distillation tower 19. In this embodiment, the aldehyde distillation tower 19 is, for example, a plate distillation tower or a packed distillation tower, and the utility model does not limit the type of the aldehyde distillation tower 19.

[0044] See also Figure 1 As shown, in one embodiment of the utility model, the second reboiler 182 is arranged at one end of the aldehyde distillation tower 19. In this embodiment, the second reboiler 182 is, for example, arranged at the bottom of the aldehyde distillation tower 19, and is used to provide heat for the aldehyde distillation tower 19 so that the low-boiling-point substances in the crude aldehyde product can be evaporated. The second reboiler 182 is, for example, a jacketed reboiler, an internal circulation reboiler, or an external circulation reboiler, and the heat source of the second reboiler 182 is, for example, steam or electric heating.

[0045] See also Figure 1 As shown, in one embodiment of the present invention, the connecting pipe 20 is arranged between adjacent devices to realize material transportation between adjacent devices. The material of the connecting pipe 20 includes at least one of carbon steel, stainless steel, polyurethane and polytetrafluoroethylene.

[0046] In summary, the utility model provides a device for preparing carboxylic acid esters, which can avoid waste and increase economic benefits by recovering aldehyde substances in the by-product aldehyde-containing wastewater. Moreover, the device provided by the utility model recovers aldehyde substances in the aldehyde-containing wastewater and then sends them to the sewage treatment plant, which can reduce the processing load of the sewage treatment plant, does not destroy the bacteria in the sewage treatment system, and ensures the normal operation of the sewage treatment plant.

[0047] References throughout the specification to "one embodiment," "an embodiment," or "a specific embodiment" mean that the specific features, structures, or characteristics described in conjunction with the embodiment are included in at least one embodiment of the utility model, and not necessarily in all embodiments. Thus, the various appearances of the phrases "in one embodiment," "in an embodiment," or "in a specific embodiment" in different places throughout the specification do not necessarily refer to the same embodiment. In addition, the specific features, structures, or characteristics of any specific embodiment of the utility model may be combined with one or more other embodiments in any suitable manner. It should be understood that other variations and modifications of the utility model embodiments described and shown herein may be based on the teachings herein and will be considered part of the spirit and scope of the utility model.

[0048] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the utility model involved in the present application is not limited to the technical solution formed by a specific combination of the above-mentioned technical features, but should also cover other technical solutions formed by any combination of the above-mentioned technical features or their equivalent features without departing from the concept of the utility model, such as the technical solution formed by replacing the above-mentioned features with the technical features with similar functions disclosed in this application (but not limited to). In addition to the technical features described in the specification, the remaining technical features are known technologies to those skilled in the art. In order to highlight the innovative features of the present utility model, the remaining technical features will not be repeated here.

Claims

1. A device for preparing carboxylic acid esters, characterized in that: At least: Reactor; A purification device connected to the reactor; at least one separation tank, disposed on a side of the purification device away from the reactor; A sewage collection tank connected to a side of the separation tank away from the purification device; At least one buffer tank is arranged on a side of the sewage collection tank away from the separation tank; A sewage stripping tower is arranged on a side of the buffer tank away from the sewage collecting tank; an aldehyde distillation tower connected to the sewage stripping tower; as well as Connect pipes and adjacent equipment.

2. The device according to claim 1, characterized in that The device further comprises a sewage delivery pump, which is arranged between the sewage collection tank and the buffer tank.

3. The device according to claim 2, characterized in that When there is one buffer tank, the buffer tank is arranged between the sewage delivery pump and the sewage stripping tower.

4. The device according to claim 2, characterized in that When there are multiple buffer tanks, the multiple buffer tanks are arranged on a side of the sewage delivery pump away from the sewage collection tank, and the multiple buffer tanks are connected in parallel.

5. The device according to claim 1, characterized in that When there is one separation tank, the separation tank is arranged between the purification equipment and the sewage collection tank.

6. The device according to claim 1, characterized in that When there are multiple separation tanks, the multiple separation tanks are arranged between the purification equipment and the sewage collection tank, and the multiple separation tanks are connected in parallel.

7. The device according to claim 1, characterized in that The device further comprises a first reboiler, which is arranged at one end of the sewage stripping tower.

8. The device according to claim 7, characterized in that The aldehyde distillation tower is connected to an end of the sewage stripping tower away from the first reboiler.

9. The device according to claim 7, characterized in that The device also includes a sewage discharge pipeline, which is connected to one end of the sewage stripping tower close to the first reboiler.

10. The device according to claim 1, characterized in that The device further comprises a second reboiler, which is arranged at one end of the aldehyde distillation tower.

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