High-efficiency glyceryl triacetate neutralization reaction device

Abstract

The utility model belongs to the technical field of chemical equipment, and particularly discloses a high-efficiency glyceryl triacetate neutralization reaction device. The upper part or the top end of a neutralization kettle of the device is provided with a feed pipe and a water-alkali liquid inlet pipe, and the lower part or the bottom end is provided with a liquid outlet pipe; a stirring mechanism is rotationally arranged in the neutralization kettle, and driving equipment with an output shaft connected with the stirring mechanism is arranged outside the neutralization kettle; a return pipe is arranged at the upper part of the neutralization kettle, a filter tank of which the top end is communicated with a liquid outlet pipe of the neutralization kettle is also arranged, an outflow pipe is arranged at the side part or the bottom end of the filter tank and is communicated with the return pipe through a pipeline, and a return pump is arranged on the pipeline. The stirring mechanism is arranged in the neutralization kettle, and the filter tank and the circulating reflux pipeline are arranged at the bottom end of the neutralization kettle, so that glyceryl triacetate can be uniformly neutralized to improve the quality, the neutralization time can be shortened to avoid hydrolysis, and the reflux pump can be prevented from being blocked through the filter tank; the device has the characteristics of simple structure, simplicity and convenience in operation, high neutralization efficiency and difficulty in blockage.

Description

Technical Field

[0001] The utility model belongs to the technical field of chemical equipment, and in particular relates to a high-efficiency glyceryl triacetate neutralization reaction device which has the advantages of simple structure, easy operation and low clogging. Background Art

[0002] Glyceryl triacetate is a colorless oily liquid widely used in daily chemical flavor formulations, mainly used as a fixative. At present, the main industrial route for preparing glyceryl triacetate is to use glycerol as a raw material to prepare glyceryl triacetate: glacial acetic acid and glycerol are used as raw materials, benzene and the like are used as water-carrying agents, and concentrated sulfuric acid is used as a catalyst. After esterification reaction, neutralization reaction, water washing treatment, drying treatment, distillation and purification, the total ester yield is 75-79%, and the purity of glyceryl triacetate is about 94%. However, the aforementioned process reaction time is relatively long, and the yield and purity of the obtained glyceryl triacetate are both low. To this end, the applicant uses concentrated sulfuric acid and activated carbon to prepare a catalyst, and then esterifies the catalyst with glycerol, acetic acid and a water-carrying agent, and then decolorizes, extracts acid, neutralizes, dehydrates, and filters to finally obtain glyceryl triacetate with a purity of ≥99.70%.

[0003] In the existing commonly used triacetin preparation process, after the esterification reaction, a neutralization reaction is required to adjust the pH value. At present, the neutralization reaction is generally carried out by adding a sodium carbonate solution, a sodium hydroxide solution and other water bases, but since triacetin is easily hydrolyzed in the water base, which affects the yield and purity of triacetin, it is necessary to shorten the neutralization reaction time as much as possible, but insufficient neutralization reaction time will cause uneven mixing of the water base and triacetin, making the pH value of triacetin unstable, which not only increases the difficulty of controlling the production process after the neutralization reaction, but also ultimately affects the purity of the triacetin finished product. To this end, in the prior art, a stirring device is generally provided in the neutralization reaction kettle or the neutralization reaction tower to increase the mixing speed of water alkali and triacetin, thereby improving the uniformity of the feed liquid and shortening the neutralization time; however, since the stirring blades of the stirring device only have a good stirring effect on the surrounding feed liquid, and since the neutralization kettle or the neutralization tower generally feeds from the top and discharges from the bottom, it is easy to cause the neutralization effect of the upper and lower layers of the feed liquid to be different, so that the bottom feed liquid is discharged without being fully mixed and neutralized, thereby affecting the subsequent production and the final purity. Although the prior art can improve the effect of feed liquid mixing by increasing the stirring time, increasing the stirring speed and improving the blade structure, it leads to a complex structure and high energy consumption, and because the bottom feed liquid is often difficult to be driven by the stirring mechanism to participate in the mixing again due to the structural limitations of the neutralization kettle or the neutralization tower, the mixing effect is still not ideal. Utility Model Content

[0004] According to the shortcomings of the prior art, the utility model develops a high-efficiency triacetin neutralization reaction device which has the advantages of simple structure, easy operation and not easy to be blocked.

[0005] The utility model is implemented as follows: comprising a neutralization kettle, wherein the upper part or top end of the neutralization kettle is provided with a feed pipe connected to the front end device of the triacetin esterification reaction system, the upper part or top end of the neutralization kettle is provided with a water alkali liquid inlet pipe, and the lower part or bottom end of the neutralization kettle is also provided with a liquid outlet pipe;

[0006] A stirring mechanism is rotatably arranged inside the neutralization kettle, and a driving device is arranged outside the neutralization kettle with an output shaft connected to the stirring mechanism;

[0007] A reflux pipe is arranged on the upper part of the neutralization kettle, and a filter tank whose top end is connected to the liquid outlet pipe of the neutralization kettle is also arranged. An outlet pipe is arranged on the side or bottom of the filter tank, and the outlet pipe is connected to the reflux pipe through a pipeline, and a reflux pump is arranged on the pipeline.

[0008] Furthermore, multiple layers of filter plates are detachably fixedly arranged in the filter tank, and the filter holes on adjacent filter plates in the filter tank are staggered, or the filter holes on each layer of filter plates in the filter tank are reduced layer by layer.

[0009] Furthermore, the filter tank is provided with multiple layers of flat filter plates from top to bottom or multiple layers of cylindrical filter plates from inside to outside, the bottom ends of the multiple layers of cylindrical filter plates arranged from inside to outside in the filter tank are sealed against the bottom wall of the filter tank, and the top end is provided with a sealing top plate with an outer edge sealedly connected to the outer wall of the filter tank and a central through hole, and the liquid inlet of the outlet pipe extends to below the bottom layer of the flat filter plate or the outside of the outermost cylindrical filter plate in the filter tank.

[0010] Furthermore, the filter tank includes a top cover and a bottom tank, the top cover and the bottom tank are respectively provided with flanges, the top cover and the bottom tank are fixedly connected by bolts passing through the flanges, the top cover is connected to the liquid outlet pipe of the neutralization kettle, the filter plate is detachably fixed in the bottom tank, and the outlet pipe is arranged on the side wall of the bottom tank.

[0011] Furthermore, the bottom tank is a cylindrical tank and a conical section is provided at the lower part, the filter plate is fixedly arranged at the upper part of the bottom tank, the outlet pipe is arranged on the side wall below or in the middle of the lowest filter plate at the upper part of the bottom tank, a discharge pipe is provided at the bottom end of the conical section, and the discharge pipe is connected to a control valve I.

[0012] Furthermore, an adjusting pipe is provided on the upper part of the top cover, and the adjusting pipe is connected to a control valve II.

[0013] Furthermore, a three-way joint is provided on the pipeline, the inlet end of the three-way joint is connected to the outlet end of the reflux pump, and the two outlet ends of the three-way joint are respectively connected to the reflux pipe through the control valve III and to the back-end device of the triacetin esterification reaction system through the control valve IV.

[0014] Furthermore, the stirring mechanism comprises a stirring shaft and a stirring paddle, wherein the stirring shaft is rotatably arranged in the neutralization kettle, and the stirring paddle is circumferentially arranged on the stirring shaft at intervals.

[0015] Furthermore, a vertical shaft is rotatably provided at the upper part of the neutralization kettle, the top end of the vertical shaft is connected to the driving shaft of the driving device I at the top of the neutralization kettle, and a plurality of vertical stirring paddles I are circumferentially spaced apart on the vertical shaft; and / or a horizontal shaft is rotatably provided at the middle or lower part of the neutralization kettle, one end of the horizontal shaft is connected to the driving shaft of the driving device II on the side wall of the neutralization kettle, and a plurality of horizontal stirring paddles II are circumferentially spaced apart on the horizontal shaft.

[0016] Compared with the prior art, the beneficial effects of the utility model are:

[0017] 1. The utility model provides a stirring mechanism inside the neutralization kettle, and provides a filter tank and a pipeline at the bottom to form a circulating reflux pipeline with a reflux pump. The glyceryl triacetate and water alkali in the neutralization kettle are refluxed up and down through the circulating reflux pipeline, so that the feed liquid can be fully mixed to improve the neutralization efficiency of glyceryl triacetate, reducing the control difficulty of subsequent processes, and significantly shortening the neutralization time to reduce the impact of hydrolysis, which can effectively ensure the final purity of glyceryl triacetate.

[0018] 2. The utility model can filter sodium acetate crystals generated by the reaction of water alkali and acetic acid by setting a filter tank at the front end of the circulation reflux pipeline, thereby solving the problem of sodium acetate crystals causing blockage of the reflux pump and ensuring the smoothness of the reflux process. In particular, the multi-layer filter plates are detachably fixed in the filter tank, and the filter holes between the filter plates are staggered or gradually reduced, which can effectively slow down the blockage of the filter plates and reduce the maintenance workload; the filter tank is further set as a split structure of a top cover and a bottom tank connected by a flange, which can facilitate the replacement of the filter plates and the removal of intercepted crystals, simplifying the maintenance operation.

[0019] In summary, the utility model has the characteristics of simple structure, easy operation, high neutralization efficiency and not easy to be blocked. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is one of the structural diagrams of the utility model;

[0021] Figure 2 for Figure 1 The enlarged view of M;

[0022] Figure 3 This is the second structural diagram of the utility model;

[0023] Figure 4 for Figure 3 The enlarged view at N;

[0024] In the figure: 1-neutralization kettle, 11-feed pipe, 12-liquid inlet pipe for caustic soda, 13-reflux pipe, 2-stirring mechanism, 21-stirring shaft, 211-vertical axis, 212-horizontal axis, 22-stirring paddle, 221-stirring paddle I, 222-stirring paddle II, 3-driving device, 31-driving device I, 32-driving device II, 5-filter tank, 51-outlet pipe, 52-filter plate, 53-top cover, 54-bottom tank, 55-flange, 56-conical section, 57-discharge pipe, 58-control valve I, 59-regulating pipe, 5A-control valve II, 5B-sealed top plate, 6-pipeline, 61-tee joint, 62-control valve III, 63-control valve IV, 7-reflux pump, 8-control valve V, 9-pressure ring. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but the present invention is not limited in any way. Any changes or improvements made based on the teachings of the present invention belong to the protection scope of the present invention.

[0026] like Figures 1 to 4 As shown, the utility model comprises a neutralization kettle 1, the upper part or top end of the neutralization kettle 1 is provided with a feed pipe 11 connected to the front end device of the triacetin esterification reaction system, the upper part or top end of the neutralization kettle 1 is provided with a water-based liquid inlet pipe 12, and the lower part or bottom end of the neutralization kettle 1 is also provided with a liquid outlet pipe;

[0027] A stirring mechanism 2 is rotatably arranged inside the neutralization kettle 1, and a driving device 3 is arranged outside the neutralization kettle 1 with an output shaft connected to the stirring mechanism 2;

[0028] A reflux pipe 13 is provided at the upper portion of the neutralization kettle 1, and a filter tank 5 whose top end is connected to the liquid outlet pipe of the neutralization kettle 1 is also provided. An outlet pipe 51 is provided at the side or bottom of the filter tank 5, and the outlet pipe 51 is connected to the reflux pipe 13 through a pipeline 6, and a reflux pump 7 is provided on the pipeline 6.

[0029] Multiple layers of filter plates 52 are detachably fixedly arranged in the filter tank 5 , and the filter holes on adjacent filter plates 52 in the filter tank 5 are staggered, or the filter holes on each layer of filter plates 52 in the filter tank 5 are reduced layer by layer.

[0030] The filter tank 5 is provided with multiple layers of flat filter plates 52 from top to bottom or multiple layers of cylindrical filter plates 52 from inside to outside. The bottom ends of the multiple layers of cylindrical filter plates 52 arranged from inside to outside in the filter tank 5 are sealed against the bottom wall of the filter tank 5, and the top end is provided with a sealing top plate 5B with an outer edge sealedly connected to the outer wall of the filter tank 5 and a central through hole. The liquid inlet of the outlet pipe 51 extends to the bottom of the flat filter plate 52 at the bottom layer or the outside of the cylindrical filter plate 52 at the outermost layer in the filter tank 5.

[0031] The filter tank 5 includes a top cover 53 and a bottom tank 54. The top cover 53 and the bottom tank 54 are respectively provided with flanges 55. The top cover 53 and the bottom tank 54 are fixedly connected by bolts penetrating the flanges 55. The top cover 53 is connected to the liquid outlet pipe of the neutralization kettle 1. The filter plate 52 is detachably fixed in the bottom tank 54. The outlet pipe 51 is arranged on the side wall of the bottom tank 54.

[0032] The bottom tank 54 is a cylindrical tank and is provided with a conical section 56 at the lower part. The filter plate 52 is fixedly arranged at the upper part of the bottom tank 54. The outlet pipe 51 is arranged on the side wall below or in the middle of the lowest filter plate 52 at the upper part of the bottom tank 54. A discharge pipe 57 is arranged at the bottom end of the conical section 56, and a control valve I 58 is connected to the discharge pipe 57.

[0033] A pressure ring 9 is detachably embedded on the flange 55 of the top cover 53 and the bottom tank 54 , and the bottom end of the inner side of the pressure ring 9 extends into the bottom tank 54 and presses against the sealing top plate 5B.

[0034] The top cover 53 is also provided with a regulating pipe 59, which is connected to a control valve II5A. The regulating pipe 59 can be used as an overflow port, an exhaust port, a feed port of the filter tank 5 or a reverse flushing outlet of the filter plate 52 as required.

[0035] The pipeline 6 is provided with a three-way joint 61, the inlet end of the three-way joint 61 is connected to the outlet end of the reflux pump 7, and the two outlet ends of the three-way joint 61 are respectively connected to the reflux pipe 13 through the control valve III 62 and connected to the back-end device of the triacetin esterification reaction system through the control valve IV 63.

[0036] The stirring mechanism 2 includes a stirring shaft 21 and a stirring paddle 22 . The stirring shaft 21 is rotatably disposed in the neutralization kettle 1 , and the stirring paddles 22 are circumferentially spaced on the stirring shaft 21 .

[0037] A vertical shaft 211 is rotatably provided at the upper part of the neutralization kettle 1, and the top end of the vertical shaft 211 is connected to the driving shaft of the driving device Ⅰ31 at the top of the neutralization kettle 1, and a plurality of vertical stirring paddles Ⅰ221 are circumferentially arranged on the vertical shaft 211; and / or a horizontal shaft 212 is rotatably provided at the middle or lower part of the neutralization kettle 1, and one end of the horizontal shaft 212 is connected to the driving shaft of the driving device Ⅱ32 on the side wall of the neutralization kettle 1, and a plurality of horizontal stirring paddles Ⅱ222 are circumferentially arranged on the horizontal shaft 212.

[0038] The driving device 3 is an electric motor or a hydraulic rotary motor.

[0039] The working principle and working process of this utility model:

[0040] like Figure 3 and 4 As shown, the crude triacetin generated by the esterification reaction, after decolorization and acid extraction, enters the neutralization kettle 1 through the feed pipe 11 (at this time, the control valve I58, the control valve II5A and the control valve IV63 are closed, and the control valve III62 and the control valve V8 are opened), and then the sodium carbonate solution is added from the soda ash inlet pipe 12 according to the operating procedures, and the motor (i.e., the drive setting 3) is started to drive the stirring mechanism 2 to rotate and stir, so that the sodium carbonate and the crude triacetin are mixed and neutralized; at the same time, the reflux pump 7 is started, and the feed liquid at the bottom of the neutralization kettle 1 enters the filter tank 5 under the action of its own weight and is filtered out by the filter plate 52 to remove the sodium acetate crystals, and then enters the reflux pipe 13 through the outlet pipe 51, the reflux pump 7, and the pipeline 6, so that the feed liquid circulates up and down in the neutralization kettle 1 to reflux for neutralization reaction. After the neutralization application reaches a predetermined time or the test is qualified, the control valve III 62 is closed and the control valve IV 63 is opened, and the triacetin glyceryl after the neutralization reaction is output to the device at the back end of the esterification reaction system for further dehydration and filtration, and finally the triacetin glyceryl ester product is obtained.

[0041] After the filter tank 5 has been working for a predetermined time, close the control valve V8 or empty the liquid in the kettle 1 and the filter tank 5, remove the bolts on the flange 55 of the filter tank 5, separate the top cover 53 and the bottom tank 54, and then remove the crystals intercepted by the filter plate 52 or replace the damaged filter plate 52.

[0042] The above is only a preferred specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the utility model should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A highly efficient triacetin neutralization reaction device, comprising a neutralization kettle (1), wherein the upper portion or top end of the neutralization kettle (1) is provided with a feed pipe (11) connected to a front end device of a triacetin esterification reaction system, the upper portion or top end of the neutralization kettle (1) is provided with a water-based liquid inlet pipe (12), and the lower portion or bottom end of the neutralization kettle (1) is also provided with a liquid outlet pipe; It is characterized in that A stirring mechanism (2) is rotatably arranged inside the neutralization kettle (1), and a driving device (3) is arranged outside the neutralization kettle (1) and has an output shaft connected to the stirring mechanism (2); The neutralization kettle (1) is provided with a reflux pipe (13) at the top, and a filter tank (5) whose top end is connected to the liquid outlet pipe of the neutralization kettle (1). The filter tank (5) is provided with an outlet pipe (51) at the side or bottom, and the outlet pipe (51) is connected to the reflux pipe (13) through a pipeline (6). A reflux pump (7) is provided on the pipeline (6).

2. The highly efficient triacetin neutralization reaction device according to claim 1, characterized in that: Multiple layers of filter plates (52) are detachably fixedly arranged in the filter tank (5), and the filter holes on adjacent filter plates (52) in the filter tank (5) are staggered, or the filter holes on each layer of filter plates (52) in the filter tank (5) are reduced layer by layer.

3. The highly efficient triacetin neutralization reaction device according to claim 2, characterized in that: The filter tank (5) is provided with multiple layers of flat filter plates (52) from top to bottom or multiple layers of cylindrical filter plates (52) from inside to outside. The bottom ends of the multiple layers of cylindrical filter plates (52) arranged from inside to outside in the filter tank (5) are in sealing contact with the bottom wall of the filter tank (5), and the top ends are provided with a sealing top plate (5B) with an outer edge sealedly connected to the outer wall of the filter tank (5) and a central through hole. The liquid inlet of the outlet pipe (51) extends to the bottom of the bottom flat filter plate (52) or the outside of the outermost cylindrical filter plate (52) in the filter tank (5).

4. The highly efficient triacetin neutralization reaction device according to claim 2, characterized in that: The filter tank (5) comprises a top cover (53) and a bottom tank (54); the top cover (53) and the bottom tank (54) are respectively provided with flanges (55); the top cover (53) and the bottom tank (54) are fixedly connected via bolts penetrating the flanges (55); the top cover (53) is connected to a liquid outlet pipe of a neutralization kettle (1); the filter plate (52) is detachably fixedly arranged in the bottom tank (54); and the outlet pipe (51) is arranged on a side wall of the bottom tank (54).

5. The highly efficient triacetin neutralization reaction device according to claim 4, characterized in that: The bottom tank (54) is a cylindrical tank and is provided with a conical section (56) at the bottom. The filter plate (52) is fixedly arranged at the upper part of the bottom tank (54). The outlet pipe (51) is arranged on the side wall below or in the middle of the lowest filter plate (52) at the upper part of the bottom tank (54). A discharge pipe (57) is provided at the bottom end of the conical section (56), and a control valve I (58) is connected to the discharge pipe (57).

6. The highly efficient triacetin neutralization reaction device according to claim 4, characterized in that: The upper portion of the top cover (53) is also provided with a regulating pipe (59), and the regulating pipe (59) is connected to a control valve II (5A).

7. The high-efficiency triacetin neutralization reaction device according to any one of claims 1 to 6, characterized in that: The pipeline (6) is provided with a three-way joint (61), the inlet end of the three-way joint (61) is connected to the outlet end of the reflux pump (7), and the two outlet ends of the three-way joint (61) are respectively connected to the reflux pipe (13) through a control valve III (62) and are connected to the back-end device of the triacetin esterification reaction system through a control valve IV (63).

8. The highly efficient triacetin neutralization reaction device according to claim 7, characterized in that: The stirring mechanism (2) comprises a stirring shaft (21) and a stirring paddle (22); the stirring shaft (21) is rotatably arranged in the neutralization kettle (1); and the stirring paddles (22) are circumferentially arranged on the stirring shaft (21) at intervals.

9. The highly efficient triacetin neutralization reaction device according to claim 8, characterized in that: A vertical shaft (211) is rotatably arranged at the upper part of the neutralization kettle (1), the top end of the vertical shaft (211) is connected to the driving shaft of the driving device I (31) at the top of the neutralization kettle (1), and a plurality of vertical stirring paddles I (221) are arranged at intervals in the circumferential direction of the vertical shaft (211); and / or a horizontal shaft (212) is rotatably arranged at the middle or lower part of the neutralization kettle (1), one end of the horizontal shaft (212) is connected to the driving shaft of the driving device II (32) on the side wall of the neutralization kettle (1), and a plurality of horizontal stirring paddles II (222) are arranged at intervals in the circumferential direction of the horizontal shaft (212).

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