An esterification device for producing poly (penta-bromobenzyl acrylate)

Abstract

The utility model discloses a kind of esterification devices for polyacrylic acid pentabromobenzyl ester production, including esterification kettle, stirring mechanism is equipped in esterification kettle, stirring mechanism includes the stirring shaft of being equipped in esterification kettle, stirring shaft is connected with the stirring motor of being equipped in the top of esterification kettle, multiple layers sawtooth stirring vane are equipped on stirring shaft, slurry stirring vane is also equipped between each layer sawtooth stirring vane, slurry stirring vane outside is connected with flow guide cylinder, the outside of flow guide cylinder is equipped with multiple fins in circumference;The top of esterification kettle is communicated with reflux condenser, the liquid outlet of reflux condenser is communicated with esterification kettle, the gas outlet of reflux condenser is sequentially communicated with primary absorption tower and secondary absorption tower, and the gas outlet of secondary absorption tower is communicated with discharge cylinder by first fan. The device esterification efficiency is high, tail gas in esterification reaction process is effectively treated, avoid its pollution to environment.

Description

Technical Field

[0001] This utility model relates to the field of chemical equipment technology, specifically to an esterification device for the production of pentabromobenzyl polyacrylate. Background Technology

[0002] Pentabromobenzyl polyacrylate is an important polymeric reactive flame retardant. Due to its excellent flame retardant properties, thermal stability, and good compatibility with polymer matrices, it is widely used in the flame retardant modification of materials such as polyolefins, polystyrene, engineering plastics, and synthetic rubber.

[0003] The synthesis process of pentabromobenzyl polyacrylate mainly includes: esterification of aluminum acrylate with pentabromobenzyl bromide to prepare pentabromobenzyl acrylate monomer, followed by polymerization of the pentabromobenzyl acrylate monomer in anhydrous isopropanol solution to obtain the target product, pentabromobenzyl polyacrylate. The main problem with existing esterification equipment is that traditional esterification reactors often face serious mixing efficiency issues in the synthesis of pentabromobenzyl polyacrylate in high-viscosity systems. The viscosity of the material increases sharply in the later stages of the esterification reaction, leading to difficulty in stirring, uneven heat distribution, and increased side reactions. This not only affects esterification efficiency but also the purity and yield of the product. Furthermore, the esterification reaction usually generates a large amount of hydrogen bromide gas, which, if not treated promptly, will pollute the environment. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide an esterification device for the production of pentabromobenzyl polyacrylate, which has high esterification efficiency and effectively treats the tail gas in the esterification reaction process, thus avoiding environmental pollution.

[0005] To solve the above-mentioned technical problems, the technical solution of this utility model is as follows:

[0006] An esterification apparatus for the production of pentabromobenzyl polyacrylate includes an esterification kettle. The esterification kettle is equipped with a stirring mechanism. The stirring mechanism includes a stirring shaft disposed inside the esterification kettle. The stirring shaft is connected to a stirring motor disposed at the top of the esterification kettle. The stirring shaft is provided with multiple layers of serrated stirring blades. A paddle stirring blade is also provided between each layer of serrated stirring blades. A guide tube is connected to the outside of the paddle stirring blades. Multiple fins are provided on the outer circumference of the outer side of the guide tube.

[0007] The top of the esterification reactor is connected to a reflux condenser. The liquid outlet of the reflux condenser is connected to the esterification reactor. The gas outlet of the reflux condenser is connected in sequence to a primary absorption tower and a secondary absorption tower. The gas outlet of the secondary absorption tower is connected to an exhaust stack through a first fan.

[0008] Preferably, the ends of the fins are provided with turbulence grooves.

[0009] Preferably, the reflux condenser is equipped with a spiral coil, which is connected to the heat exchange medium delivery pipe through pipes and valves.

[0010] Preferably, the outer side of the spiral coil is provided with multiple heat sinks, and the heat sinks are provided with multiple turbulence holes.

[0011] Preferably, both the primary absorption tower and the secondary absorption tower are equipped with an alkaline spraying mechanism. The alkaline spraying mechanism includes a multi-layer spraying plate connected to an alkaline pipeline. The spraying plate is equipped with multiple spray pipes, and the ends and side walls of the spray pipes are equipped with multiple liquid outlet holes.

[0012] Preferably, a packing layer is provided between adjacent spray plates of the primary absorption tower and the secondary absorption tower.

[0013] Preferably, the bottom of the primary absorption tower is provided with a first liquid storage tank, which is connected to the alkaline solution pipeline of the primary absorption tower through a first circulation pipeline, and a first circulation pump is provided on the first circulation pipeline; a first pH sensor is provided in the first liquid storage tank, the first liquid storage tank is connected to the alkaline solution storage tank, a first electric valve is provided on the connecting pipeline between the first liquid storage tank and the alkaline solution storage tank, and the first pH sensor is interlocked with the first electric valve.

[0014] Preferably, the bottom of the secondary absorption tower is provided with a second liquid storage tank, which is connected to the alkaline solution pipeline of the secondary absorption tower through a second circulation pipeline, and a second circulation pump is provided on the second circulation pipeline; a second pH sensor is provided in the second liquid storage tank, the second liquid storage tank is connected to the alkaline solution storage tank, a second electric valve is provided on the connecting pipeline between the second liquid storage tank and the alkaline solution storage tank, and the second pH sensor is interlocked with the second electric valve.

[0015] Preferably, both the primary absorption tower and the secondary absorption tower are equipped with wire mesh demisters at their outlets.

[0016] Preferably, the outlet of the secondary absorption tower is connected to the exhaust main pipe, the exhaust main pipe is connected to the discharge cylinder through the exhaust branch pipe, the exhaust main pipe is connected to the inlet of the primary absorption tower through the third circulation pipe and the second fan, the exhaust main pipe is equipped with an online pH meter, the exhaust branch pipe and the third circulation pipe are respectively equipped with a third electric valve and a fourth electric valve, and the online pH meter is interlocked with the third electric valve and the fourth electric valve respectively.

[0017] Due to the adoption of the above technical solution, the beneficial effects of this utility model are:

[0018] This invention provides an esterification apparatus for the production of pentabromobenzyl polyacrylate, comprising an esterification kettle, a stirring mechanism inside the kettle, and a stirring shaft connected to a stirring motor located at the top of the kettle. The stirring shaft has multiple layers of serrated stirring blades, with paddle-type stirring blades between each layer. A guide tube is connected to the outer side of each paddle-type stirring blade, and multiple fins are arranged circumferentially on the outer side of the guide tube. A reflux condenser is connected to the top of the esterification kettle, with its liquid outlet connected to the esterification kettle. The gas outlet of the reflux condenser is sequentially connected to a primary absorption tower and a secondary absorption tower. The gas outlet of the secondary absorption tower is connected to an exhaust stack via a first fan. This configuration not only increases the esterification efficiency but also effectively treats the exhaust gas during the esterification process.

[0019] The serrated stirring blades of this device provide strong shearing force, effectively breaking up viscous materials, preventing agglomeration, increasing the contact area of ​​reactants, and accelerating the esterification reaction rate. The combined arrangement of the paddle-type stirring blades and the guide tube guides the materials in the reactor to form a strong axial circulation flow, ensuring uniform mixing throughout the reactor, eliminating dead zones, and avoiding localized overheating or incomplete reaction. The outer side of the guide tube is also equipped with fins and turbulence grooves, which disrupt the laminar boundary layer on the outer wall of the guide tube, generating eddies and turbulence, enhancing heat and mass exchange between the materials inside and outside the guide tube, and further improving mixing uniformity and heat transfer efficiency.

[0020] The spiral coil of this device is equipped with heat sinks on the outside, and the heat sinks are provided with turbulence holes. The heat sinks further increase the external heat dissipation area of ​​the reflux condenser, and the turbulence holes can disrupt the laminar flow on the outer wall of the spiral coil, enhance the turbulence of air or ambient medium, significantly improve the heat dissipation efficiency of the reflux condenser, ensure the condensation effect, and maintain a suitable reflux ratio.

[0021] The top of the primary and secondary absorption towers of this device are equipped with wire mesh demisters to effectively remove alkaline mist entrained in the absorbed gas, ensuring the cleanliness of the emitted gas.

[0022] The primary and secondary absorption tower structures of this device enable the recycling of alkali solution, reducing alkali consumption. The first pH sensor is interlocked with the first electric valve, and the second pH sensor is interlocked with the second electric valve to monitor the pH value of the solution in the first and second storage tanks in real time. When the pH value falls below the set value, the first or second electric valve automatically opens to replenish fresh alkali solution, maintaining stable absorption efficiency.

[0023] The outlet of the secondary absorption tower of this device is connected to the exhaust main pipe. The exhaust main pipe is connected to the discharge stack via an exhaust branch pipe. The exhaust main pipe is connected to the inlet of the primary absorption tower via a third circulation pipe and a second fan. An online pH meter is installed on the exhaust main pipe. A third electric valve and a fourth electric valve are respectively installed on the exhaust branch pipe and the third circulation pipe. The online pH meter is interlocked with the third electric valve and the fourth electric valve. The above settings can monitor the acidity of the final exhaust gas in real time. When the pH meets the standard, the third electric valve is opened and the fourth electric valve is closed, and the gas is directly discharged into the discharge stack. If the pH does not meet the standard, the third electric valve is closed, the fourth electric valve is opened, and the second fan is started to send the gas that does not meet the standard back to the inlet of the primary absorption tower for re-absorption treatment, ensuring that the exhaust gas is fully treated. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model;

[0026] Figure 2 yes Figure 1 Enlarged structural diagram at point A;

[0027] Figure 3 yes Figure 1 Enlarged structural diagram at point B;

[0028] Figure 4 yes Figure 1 Enlarged structural diagram at point C;

[0029] In the diagram, 1. Esterification reactor; 2. Stirring shaft; 3. Stirring motor; 4. Serrated stirring blades; 5. Paddle stirring blades; 6. Flow guide tube; 7. Fins; 8. Reflux condenser; 9. Spiral coil; 10. Primary absorption tower; 11. Secondary absorption tower; 12. First blower; 13. Discharge cylinder; 14. Alkali solution pipeline; 15. Spray tray; 16. Spray pipe; 17. Liquid outlet; 18. Packing layer; 19. Turbulence channel; 20. Heat sink; 21. Turbulence hole; 22. First liquid storage tank; 23. 24. First circulation pipeline; 25. First circulation pump; 26. First pH sensor; 27. Alkali storage tank; 28. First electric valve; 29. ​​Second storage tank; 30. Second circulation pipeline; 31. Second circulation pump; 32. Second pH sensor; 33. Second electric valve; 34. Wire mesh demister; 35. Main exhaust pipe; 36. Branch exhaust pipe; 37. Third circulation pipeline; 38. Second fan; 39. Online pH meter; 40. Third electric valve; 51. Fourth electric valve. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0031] Example

[0032] like Figure 1-4 As shown, an esterification apparatus for the production of pentabromobenzyl polyacrylate includes an esterification vessel 1. The esterification vessel 1 is equipped with a stirring mechanism, which includes a stirring shaft 2 located within the esterification vessel 1. The stirring shaft 2 is connected to a stirring motor 3 located at the top of the esterification vessel 1. The stirring shaft 2 has multiple layers of serrated stirring blades 4, and paddle-type stirring blades 5 are provided between each layer of serrated stirring blades 4. A guide tube 6 is connected to the outer side of each paddle-type stirring blade 5. Multiple fins 7 are provided circumferentially on the outer side of the guide tube 6. The aforementioned stirring mechanism improves the mixing efficiency of the esterification reaction materials, avoids uneven local concentrations leading to side reactions, and thus improves product purity and yield.

[0033] The top of the esterification reactor 1 is connected to a reflux condenser 8, and the reflux condenser 8 is equipped with a spiral coil 9. The spiral coil 9 is connected to a heat exchange medium delivery pipe (not shown in the figure) through pipes and valves. The liquid outlet of the reflux condenser 8 is connected to the esterification reactor 1. The spiral coil 9 in the reflux condenser 8 improves the condensation efficiency, thereby improving the reflux efficiency.

[0034] The gas outlet of the reflux condenser 8 is sequentially connected to the primary absorption tower 10 and the secondary absorption tower 11. The gas outlet of the secondary absorption tower 11 is connected to the discharge cylinder 13 via the first fan 12. Both the primary absorption tower 10 and the secondary absorption tower 11 are equipped with an alkaline spraying mechanism. The alkaline spraying mechanism includes a multi-layer spray plate 15 connected to the alkaline pipe 14. The spray plate 15 is equipped with multiple spray pipes 16, and the ends and side walls of the spray pipes 16 are equipped with multiple liquid outlet holes 17. A packing layer 18 is provided between adjacent spray plates 15 in the primary absorption tower 10 and the secondary absorption tower 11. The absorption and treatment of hydrogen bromide in the tail gas by alkaline solution is achieved through the primary absorption tower 10 and the secondary absorption tower 11.

[0035] In this embodiment, the end of the fin 7 is provided with a turbulence groove 19. The combined arrangement of the fin 7 and the turbulence groove 19 can disrupt the laminar boundary layer on the outer wall of the guide tube 6, generating eddies and turbulence, enhancing the heat and mass exchange of materials inside and outside the guide tube 6, and further improving the mixing uniformity and heat transfer efficiency.

[0036] In this embodiment, the outer side of the spiral coil 9 is provided with multiple heat dissipation fins 20, and the heat dissipation fins 20 are provided with multiple turbulence holes 21. The heat dissipation fins 20 can further increase the external heat dissipation area of ​​the reflux condenser 8, and the turbulence holes 21 disrupt the laminar flow on the outer wall of the spiral coil 9, significantly improving the heat dissipation efficiency of the reflux condenser 8, ensuring the condensation effect, and maintaining a suitable reflux ratio.

[0037] In this embodiment, the bottom of the primary absorption tower 10 is provided with a first storage tank 22, which is connected to the alkaline solution pipeline (not shown in the figure) of the primary absorption tower 10 through a first circulation pipe 23. A first circulation pump 24 is provided on the first circulation pipe 23. A first pH sensor 25 is provided in the first storage tank 22. The first storage tank 22 is connected to the alkaline solution storage tank 26. A first electric valve 27 is provided on the connecting pipe between the first storage tank 22 and the alkaline solution storage tank 26. The first pH sensor 25 and the first electric valve 27 are interlocked. The bottom of the secondary absorption tower 11 is provided with a second storage tank 28, which is connected to the alkaline solution pipeline of the secondary absorption tower 10 through a second circulation pipe 29. A second circulation pump 30 is provided on the second circulation pipe 29. A second pH sensor 31 is provided in the second storage tank 28. The second storage tank 28 is connected to the alkaline solution storage tank 26. A second electric valve 32 is provided on the connecting pipe between the second storage tank 28 and the alkaline solution storage tank 26. The second pH sensor 31 and the second electric valve 32 are interlocked. The pH value of the absorbent in the first storage tank 22 and the second storage tank 28 can be monitored in real time through the above settings. When the pH value is lower than the set value, the first electric valve 27 or the second electric valve 32 will be automatically opened by the external control system to replenish fresh alkali solution and maintain stable absorption efficiency.

[0038] In this embodiment, both the primary absorption tower 10 and the secondary absorption tower 11 are equipped with wire mesh demisters 33 at their outlets, which can effectively remove alkaline mist entrained in the absorbed gas.

[0039] In this embodiment, the outlet of the secondary absorption tower 11 is connected to the exhaust main pipe 34. The exhaust main pipe 29 is connected to the discharge cylinder 13 through the exhaust branch pipe 35. The exhaust main pipe 34 is connected to the inlet of the primary absorption tower 10 through the third circulation pipe 36 and the second fan 37. An online pH meter 38 is installed on the exhaust main pipe 34. A third electric valve 39 and a fourth electric valve 40 are respectively installed on the exhaust branch pipe 35 and the second circulation pipe 36. The online pH meter 38 is connected to the third electric valve 39 and the fourth electric valve 40 respectively. The system includes an interlocking valve 40; a combined setup of an online pH meter 38, a third electric valve 39, and a fourth electric valve 40 to monitor the acidity of the final exhaust gas in real time. When the pH meets the standard, the third electric valve 39 on the exhaust manifold 35 is opened, and the fourth electric valve 40 is closed, allowing the gas to be directly discharged into the exhaust stack 13. When the pH does not meet the standard, the third electric valve 39 on the exhaust manifold 35 is closed, the fourth electric valve 40 is opened, and the second fan 37 is started to send the substandard gas back to the inlet of the primary absorption tower 10 for re-absorption treatment.

[0040] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An esterification apparatus for the production of pentabromobenzyl polyacrylate, characterized in that: The device includes an esterification reactor, which is equipped with a stirring mechanism. The stirring mechanism includes a stirring shaft located inside the esterification reactor and connected to a stirring motor located at the top of the esterification reactor. The stirring shaft is provided with multiple layers of serrated stirring blades, and paddle stirring blades are provided between each layer of serrated stirring blades. A guide tube is connected to the outside of the paddle stirring blades, and multiple fins are provided on the outer circumference of the guide tube. The top of the esterification reactor is connected to a reflux condenser. The liquid outlet of the reflux condenser is connected to the esterification reactor. The gas outlet of the reflux condenser is connected in sequence to a primary absorption tower and a secondary absorption tower. The gas outlet of the secondary absorption tower is connected to an exhaust stack through a first fan.

2. The esterification apparatus for producing pentabromobenzyl polyacrylate according to claim 1, characterized in that: The ends of the fins are provided with turbulence grooves.

3. The esterification apparatus for producing pentabromobenzyl polyacrylate according to claim 1, characterized in that: The reflux condenser is equipped with a spiral coil, which is connected to the heat exchange medium delivery pipe through pipes and valves.

4. The esterification apparatus for producing pentabromobenzyl polyacrylate according to claim 3, characterized in that: The outer side of the spiral coil is provided with multiple heat sinks, and the heat sinks are provided with multiple turbulence holes.

5. The esterification apparatus for producing pentabromobenzyl polyacrylate according to claim 1, characterized in that: Both the primary and secondary absorption towers are equipped with an alkaline spraying mechanism. The alkaline spraying mechanism includes a multi-layer spraying plate connected to the alkaline pipeline. The spraying plate is equipped with multiple spray pipes, and the ends and side walls of the spray pipes are equipped with multiple liquid outlet holes.

6. The esterification apparatus for producing pentabromobenzyl polyacrylate according to claim 5, characterized in that: A packing layer is provided between adjacent spray plates in both the primary and secondary absorption towers.

7. The esterification apparatus for producing pentabromobenzyl polyacrylate according to claim 1, characterized in that: The bottom of the primary absorption tower is provided with a first liquid storage tank, which is connected to the alkaline solution pipeline of the primary absorption tower through a first circulation pipeline. A first circulation pump is provided on the first circulation pipeline. A first pH sensor is provided in the first liquid storage tank. The first liquid storage tank is connected to an alkaline solution storage tank. A first electric valve is provided on the connecting pipeline between the first liquid storage tank and the alkaline solution storage tank. The first pH sensor is interlocked with the first electric valve.

8. The esterification apparatus for producing pentabromobenzyl polyacrylate according to claim 7, characterized in that: The bottom of the secondary absorption tower is provided with a second liquid storage tank, which is connected to the alkaline solution pipeline of the secondary absorption tower through a second circulation pipeline. A second circulation pump is provided on the second circulation pipeline. A second pH sensor is provided in the second liquid storage tank. The second liquid storage tank is connected to the alkaline solution storage tank. A second electric valve is provided on the connecting pipeline between the second liquid storage tank and the alkaline solution storage tank. The second pH sensor and the second electric valve are interlocked.

9. The esterification apparatus for producing pentabromobenzyl polyacrylate according to claim 1, characterized in that: Both the primary and secondary absorption towers are equipped with wire mesh demisters at their outlets.

10. An esterification apparatus for producing pentabromobenzyl polyacrylate according to claim 1, characterized in that: The outlet of the secondary absorption tower is connected to the exhaust main pipe, which is connected to the discharge cylinder through an exhaust branch pipe. The exhaust main pipe is connected to the inlet of the primary absorption tower through a third circulation pipe and a second fan. An online pH meter is installed on the exhaust main pipe. A third electric valve and a fourth electric valve are respectively installed on the exhaust branch pipe and the third circulation pipe. The online pH meter is interlocked with the third electric valve and the fourth electric valve.

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