Synthesis system for glycine

Abstract

The utility model discloses a glycine synthesis system, which belongs to the technical field of glycine production and is characterized in that a chloroacetic acid concentrated solution, a urotropine concentrated solution and liquid ammonia are added into a reaction kettle and are kept within a certain pH value range, the reaction is kept for a period of time after the dropwise addition is finished, and the materials sequentially flow through a first cooler and a first centrifugal machine; adding a solid material separated by the first separator into a high-temperature pulping kettle, enabling a liquid material separated by the first centrifugal machine to flow into an alcohol precipitation kettle for continuous extraction and synthesis, enabling the material to enter a third centrifugal machine, and adding a solid material separated by the third centrifugal machine into the high-temperature pulping kettle; a liquid material separated by the third separator is added into a water methanol rectifying tower to recover water methanol and flows into a water methanol transfer tank to be stored, water methanol is added into the high-temperature pulping kettle to be subjected to reflux pulping and then flows into a second centrifugal machine, qualified glycine products flow out through a product discharging pipe, and a liquid material separated by the second centrifugal machine flows into the water methanol rectifying tower.

Description

Technical Field

[0001] The utility model belongs to the technical field of glycine production, and particularly relates to a synthesis system for glycine. Background Technique

[0002] Glycine is the simplest amino acid. As an important chemical intermediate, it is widely used in industries such as pesticides, pharmaceuticals, and food. One of its important uses is for the synthesis of glyphosate. Currently, there are mainly two methods for synthesizing glycine at home and abroad, namely the ammonia method of aminoacetic acid and the Strecker method. In China, the ammonia method is mainly used as the main production method. In the traditional ammonia method, the chloroacetic acid solution is first heated to 50 - 70 °C and then ammonia gas is introduced, and the reaction is carried out under the catalysis of hexamethylenetetramine. This process has problems such as low powder yield and low product purity. We have carried out further research on this process, optimized each step, and improved the industrial application value of this method. Content of the Utility Model

[0003] To solve the problems of low powder yield and low product purity in the prior art, the utility model provides a synthesis system for glycine. The concentrated chloroacetic acid solution, the concentrated hexamethylenetetramine solution, and liquid ammonia are added into the reaction kettle, and within a certain pH value range is maintained. After the dropping is completed, the reaction is kept warm for a period of time. The material flows through the first cooler and the first centrifuge in sequence. The solid material separated by the first separator is added to the high-temperature pulping kettle through the first feeding pipe. The liquid material separated by the first centrifuge flows into the alcohol precipitation kettle through the second feeding pipe to continue extraction and synthesis. The material enters the third centrifuge. The solid material separated by the third separator is added to the high-temperature pulping kettle through the fourth feeding pipe. The liquid material separated by the third separator is added to the water-methanol rectification tower through the fifth feeding pipe to recover water-methanol and flows into the water-methanol transfer tank for storage. After adding water-methanol for reflux pulping, the high-temperature pulping kettle flows into the second centrifuge. The qualified glycine product flows out through the product discharge pipe. The liquid material separated by the second centrifuge flows into the water-methanol rectification tower through the second feeding pipe. The qualified glycine product obtained by the utility model has the advantages of high powder yield and high product purity.

[0004] The purpose of the utility model is achieved through the following technical solutions:

[0005] A synthesis system for glycine, comprising a reaction kettle, wherein a chloroacetic acid concentrated solution feeding unit, a hexamethylenetetramine concentrated solution feeding unit, a liquid ammonia feeding pipe and a first discharge pipe are arranged on the reaction kettle. A first discharge valve is arranged on the first discharge pipe. The first discharge pipe is also connected to a first cooler and a first centrifuge. The first centrifuge is respectively connected to a first distribution pipe and a second distribution pipe. The first distribution pipe is connected to a high-temperature pulping kettle. The second distribution pipe is connected to an alcohol precipitation kettle. A fourth discharge pipe is arranged on the alcohol precipitation kettle. The fourth discharge pipe is also connected to a third centrifuge. The third centrifuge is respectively connected to a fourth distribution pipe and a fifth distribution pipe. The fifth distribution pipe is connected to a water-methanol rectification tower. A sewage discharge pipe and a second discharge pipe are arranged on the water-methanol rectification tower. The second discharge pipe is connected to a water-methanol transfer tank. The water-methanol transfer tank is connected to the high-temperature pulping kettle through a water-methanol feeding pipe. The high-temperature pulping kettle is also connected to a third discharge pipe and a fourth distribution pipe. The third discharge pipe is connected to a second centrifuge. The second centrifuge is connected to a product discharge pipe and a third distribution pipe. The third distribution pipe is connected to the water-methanol rectification tower.

[0006] Preferably, the chloroacetic acid concentrated solution feeding unit includes a chloroacetic acid solution feeding pipe, a first evaporation concentrator and a first transfer pipe which are connected in sequence. A first feeding valve is arranged on the first transfer pipe. A first densitometer is arranged on the first evaporation concentrator. The first densitometer detects the concentration of the chloroacetic acid solution in the first evaporation concentrator and transmits this information to the DCS. When the concentration of the chloroacetic acid solution reaches a preset value, the DCS controls the opening of the first feeding valve.

[0007] Preferably, a second feeding valve is arranged on the chloroacetic acid solution feeding pipe.

[0008] Preferably, a first intermediate tank and a third feeding valve are also arranged in sequence on the first transfer pipe.

[0009] Preferably, the hexamethylenetetramine concentrated solution feeding unit includes a hexamethylenetetramine solution feeding pipe, a second evaporation concentrator and a second transfer pipe which are connected in sequence. A fourth feeding valve is arranged on the second transfer pipe. A second densitometer is arranged on the second evaporation concentrator. The second densitometer detects the concentration of the hexamethylenetetramine solution in the second evaporation concentrator and transmits this information to the DCS. When the concentration of the hexamethylenetetramine solution reaches a preset value, the DCS controls the opening of the fourth feeding valve.

[0010] Preferably, a fifth feeding valve is arranged on the hexamethylenetetramine solution feeding pipe.

[0011] Preferably, a second intermediate tank and a sixth feeding valve are also arranged in sequence on the second transfer pipe.

[0012] Preferably, a first transfer pump is provided on the first discharge pipe; a second transfer pump is provided on the second distribution pipe, a third transfer pump is provided on the third distribution pipe, a fourth transfer pump is provided on the fifth distribution pipe, and a water-methanol transfer pump is provided on the water-methanol feed pipe.

[0013] Preferably, a liquid ammonia feed valve and a liquid ammonia flowmeter are provided on the liquid ammonia feed pipe.

[0014] Preferably, a water-methanol feed valve and a water-methanol flowmeter are also provided on the water-methanol feed pipe.

[0015] The beneficial effects of this technical solution are as follows:

[0016] 1. A glycine synthesis system provided by the present utility model, wherein a chloroacetic acid concentrate, a hexamine concentrate, and liquid ammonia are added into a reaction kettle, and within a certain pH (6 - 6.5) value range, after the dropping is completed, the reaction is kept warm for a period of time. The materials flow through a first cooler and a first centrifuge in sequence. The solid materials separated by the first separator are added into a high-temperature pulping kettle through the first distribution pipe, and the liquid materials separated by the first centrifuge flow into an alcohol precipitation kettle through the second distribution pipe to continue extraction and synthesis. The materials enter a third centrifuge, and the solid materials separated by the third separator are added into the high-temperature pulping kettle through the fourth distribution pipe, and the liquid materials separated by the third separator are added into a water-methanol rectification tower through the fifth distribution pipe to recover water-methanol and flow into a water-methanol intermediate storage tank for storage. After adding water-methanol for reflux pulping, the high-temperature pulping kettle flows into a second centrifuge, and the qualified glycine flows out through the product discharge pipe. The liquid materials separated by the second centrifuge flow into the water-methanol rectification tower through the second distribution pipe. The qualified glycine obtained by the present utility model has the advantages of high powder yield and high product purity.

[0017] 2. A glycine synthesis system provided by the present utility model, wherein the chloroacetic acid solution is concentrated in a first evaporation concentrator, and a first densitometer detects the concentration of the chloroacetic acid solution in the first evaporation concentrator. When the concentration of the chloroacetic acid solution reaches 70 - 80%, it flows into a first intermediate storage tank through a first feed valve for storage, and when the reaction kettle requires chloroacetic acid concentrate, it is added into the reaction kettle through a third feed valve.

[0018] 3. A glycine synthesis system provided by the present utility model, wherein the hexamine solution is concentrated in a second evaporation concentrator, and a second densitometer detects the concentration of the hexamine solution in the second evaporation concentrator. When the concentration of the hexamine solution reaches 30 - 40%, it flows into a second intermediate storage tank through a fourth feed valve for storage, and when the reaction kettle requires hexamine concentrate, it is added into the reaction kettle through a sixth feed valve.

[0019] 4. A glycine synthesis system provided by the present utility model, wherein the liquid ammonia feed valve and the liquid ammonia flowmeter facilitate the accurate addition of liquid ammonia into the reaction kettle.

[0020] V. A synthesis system for glycine provided by the present utility model, the water-methanol feed valve and the water-methanol flowmeter facilitate and accurately add water-methanol into the high-temperature pulping kettle. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic structural diagram of the present utility model;

[0022] Figure 2 is a schematic structural diagram of Embodiment 2 in the present utility model

[0023] Among them: 100, reaction kettle; 110, chloroacetic acid concentrate feeding unit; 111, chloroacetic acid solution feeding pipe; 112, first evaporation concentrator; 113, first transfer pipe; 114, first feed valve; 115, first densitometer; 116, second feed valve; 117, first intermediate tank; 118, third feed valve; 120, hexamine concentrate feeding unit; 121, hexamine solution feeding pipe; 122, second evaporation concentrator; 123, second transfer pipe; 124, fourth feed valve; 125, second densitometer; 126, fifth feed valve; 127, second intermediate tank; 128, sixth feed valve; 200, first centrifuge; 300, high-temperature pulping kettle; 400, water-methanol rectification tower; 500, water-methanol intermediate tank; 600, second centrifuge; 700, alcohol precipitation kettle; 800, third centrifuge; 900, first cooler; 1, liquid ammonia feeding pipe; 2, first discharge pipe; 3, first discharge valve; 4, first distribution pipe; 5, second distribution pipe; 6, sewage discharge pipe; 7, second discharge pipe; 8, water-methanol feeding pipe; 9, third discharge pipe; 10, product discharge pipe; 11, third distribution pipe; 12, first transfer pump; 13, second transfer pump; 14, third transfer pump; 15, water-methanol transfer pump; 16, liquid ammonia feed valve; 17, liquid ammonia flowmeter; 18, water-methanol feed valve; 19, water-methanol flowmeter; 20, fourth transfer pump; 21, fourth discharge pipe; 22, fourth separation pipe; 23, fifth distribution pipe. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The present utility model will be further described in detail below in conjunction with the embodiments, but the embodiments of the present utility model are not limited thereto.

[0025] Embodiment 1

[0026] As Figure 1As shown in the figure, a synthesis system for glycine includes a reaction kettle 100, on which a chloroacetic acid concentrate feeding unit 110, a hexamethylenetetramine concentrate feeding unit 120, a liquid ammonia feeding pipe 1 and a first discharge pipe 2 are provided. A first discharge valve 3 is provided on the first discharge pipe 2. The first discharge pipe 2 is also connected to a first cooler 900 and a first centrifuge 200. The first centrifuge 200 is respectively connected to a first distribution pipe 4 and a second distribution pipe 5. The first distribution pipe 4 is connected to a high-temperature pulping kettle 300. The second distribution pipe 5 is connected to an alcohol precipitation kettle 700. A fourth discharge pipe 21 is provided on the alcohol precipitation kettle 700. The fourth discharge pipe 21 is also connected to a third centrifuge 800. The third centrifuge 800 is respectively connected to a fourth distribution pipe and a fifth distribution pipe 23. The fifth distribution pipe 23 is connected to a water-methanol rectification tower 400. A sewage discharge pipe 6 and a second discharge pipe 7 are provided on the water-methanol rectification tower 400. The second discharge pipe 7 is connected to a water-methanol intermediate storage tank 500. The water-methanol intermediate storage tank 500 is connected to the high-temperature pulping kettle 300 through a water-methanol feeding pipe 8. The high-temperature pulping kettle 300 is also connected to a third discharge pipe 9 and a fourth distribution pipe. The third discharge pipe 9 is connected to a second centrifuge 600. The second centrifuge 600 is connected to a product discharge pipe 10 and a third distribution pipe 11. The third distribution pipe 11 is connected to the water-methanol rectification tower 400.

[0027] Example 2

[0028] The difference between this example and Example 1 is that, as Figure 2 shown, the chloroacetic acid concentrate feeding unit 110 includes a chloroacetic acid solution feeding pipe 111, a first evaporation concentrator 112 and a first transfer pipe 113 connected in sequence. A first feeding valve 114 is provided on the first transfer pipe 113. A first densitometer 115 is provided on the first evaporation concentrator 112. The first densitometer 115 detects the concentration of the chloroacetic acid solution in the first evaporation concentrator 112 and transmits this information to the DCS. When the concentration of the chloroacetic acid solution reaches the preset value, the DCS controls to open the first feeding valve 114.

[0029] Among them, a second feeding valve 116 is provided on the chloroacetic acid solution feeding pipe 111.

[0030] Among them, a first intermediate storage tank 117 and a third feeding valve 118 are also sequentially provided on the first transfer pipe 113.

[0031] Among them, the hexamine concentrate feeding unit 120 includes a hexamine solution feeding pipe 121, a second evaporation concentrator 122, and a second transfer pipe 123 that are connected in sequence. A fourth feeding valve 124 is provided on the second transfer pipe 123, and a second densitometer 125 is provided on the second evaporation concentrator 122. The second densitometer 125 detects the concentration of the hexamine solution in the second evaporation concentrator 122 and transmits this information to the DCS. When the concentration of the hexamine solution reaches a preset value, the DCS controls the opening of the fourth feeding valve 124.

[0032] Among them, a fifth feeding valve 126 is provided on the hexamine solution feeding pipe 121.

[0033] Among them, a second intermediate tank 127 and a sixth feeding valve 128 are sequentially provided on the second transfer pipe 123.

[0034] Among them, a first transfer pump 12 is provided on the first discharge pipe 2; a second transfer pump 13 is provided on the second distribution pipe 5, a third transfer pump 14 is provided on the third distribution pipe 11, a fourth transfer pump 20 is provided on the fifth distribution pipe 23, and a water-methanol transfer pump 15 is provided on the water-methanol feeding pipe 8.

[0035] Among them, a liquid ammonia feeding valve 16 and a liquid ammonia flowmeter 17 are provided on the liquid ammonia feeding pipe 1.

[0036] Among them, a water-methanol feeding valve 18 and a water-methanol flowmeter 19 are further provided on the water-methanol feeding pipe 8.

[0037] The beneficial effects of this technical solution are as follows:

[0038] 1. A glycine synthesis system provided by the present utility model. A chloroacetic acid concentrate, a hexamethylenetetramine concentrate, and liquid ammonia are added into a reaction kettle 100. While maintaining a certain pH value (6 - 6.5), after the dropping is completed, the reaction is kept warm for a period of time. The materials flow through a first cooler 900 and a first centrifuge 200 in sequence. The solid materials separated by the first separator are added into a high-temperature pulping kettle 300 through a first material distribution pipe 4. The liquid materials separated by the first centrifuge 200 flow into an alcohol precipitation kettle 700 through a second material distribution pipe 5 for continuous extraction and synthesis. The materials enter a third centrifuge 800. The solid materials separated by the third separator are added into the high-temperature pulping kettle 300 through a fourth material distribution pipe. The liquid materials separated by the third separator are added into a water-methanol rectification tower 400 through a fifth material distribution pipe 23 to recover water-methanol and flow into a water-methanol transfer tank 500 for storage. After adding water-methanol for reflux pulping, the high-temperature pulping kettle 300 flows into a second centrifuge 600. The qualified glycine products flow out through a product discharge pipe 10. The liquid materials separated by the second centrifuge 600 flow into the water-methanol rectification tower 400 through the second material distribution pipe 5. The qualified glycine products obtained by the present utility model have the advantages of high powder yield and high product purity. The glycine solid obtained by the present utility model has a glycine content of about 99%, a chloride ion content of <0.2%, and a solid recovery rate of more than 92%.

[0039] 2. A glycine synthesis system provided by the present utility model. The chloroacetic acid solution is concentrated in a first evaporation concentrator 112. A first densitometer 115 detects the concentration of the chloroacetic acid solution in the first evaporation concentrator 112. When the concentration of the chloroacetic acid solution reaches 70 - 80%, it flows into a first intermediate tank 117 through a first feed valve 114 for storage. When the reaction kettle 100 needs the chloroacetic acid concentrate, it is added into the reaction kettle 100 through a third feed valve 118.

[0040] 3. A glycine synthesis system provided by the present utility model. The hexamethylenetetramine solution is concentrated in a second evaporation concentrator 122. A second densitometer 125 detects the concentration of the hexamethylenetetramine solution in the second evaporation concentrator 122. When the concentration of the hexamethylenetetramine solution reaches 30 - 40%, it flows into a second intermediate tank 127 through a fourth feed valve 124 for storage. When the reaction kettle 100 needs the hexamethylenetetramine concentrate, it is added into the reaction kettle 100 through a sixth feed valve 128.

[0041] 4. A glycine synthesis system provided by the present utility model. A liquid ammonia feed valve 16 and a liquid ammonia flowmeter 17 facilitate the accurate addition of liquid ammonia into the reaction kettle 100.

[0042] 5. A glycine synthesis system provided by the present utility model. A water-methanol feed valve 18 and a water-methanol flowmeter 19 facilitate the accurate addition of water-methanol into the high-temperature pulping kettle 300.

[0043] The above are only the preferred embodiments of the present utility model, and do not impose any formal restrictions on the present utility model. Any simple modifications and equivalent changes made to the above embodiments based on the technical essence of the present utility model all fall within the protection scope of the present utility model.

Claims

1. A synthetic system for glycine, characterized in that: It includes a reaction kettle (100), on which there are provided a chloroacetic acid concentrated liquid feeding unit (110), a hexamethylenetetramine concentrated liquid feeding unit (120), an ammonia liquid feeding pipe (1) and a first discharge pipe (2). A first discharge valve (3) is provided on the first discharge pipe (2). The first discharge pipe (2) is also connected to a first cooler (900) and a first centrifuge (200). The first centrifuge (200) is respectively connected to a first material distribution pipe (4) and a second material distribution pipe (5). The first material distribution pipe (4) is connected to a high-temperature beating kettle (300). The second material distribution pipe (5) is connected to an alcohol precipitation kettle (700). A fourth discharge pipe (21) is provided on the alcohol precipitation kettle (700). The fourth discharge pipe (21) is also connected to a third centrifuge (800). The third centrifuge (800) is respectively connected to a fourth material distribution pipe and a fifth material distribution pipe (23). The fifth material distribution pipe (23) is connected to a water-methanol rectification tower (400). A sewage discharge pipe (6) and a second discharge pipe (7) are provided on the water-methanol rectification tower (400). The second discharge pipe (7) is connected to a water-methanol intermediate storage tank (500). The water-methanol intermediate storage tank (500) is connected to the high-temperature beating kettle (300) through a water-methanol feeding pipe (8). The high-temperature beating kettle (300) is also connected to a third discharge pipe (9) and a fourth material distribution pipe. The third discharge pipe (9) is connected to a second centrifuge (600). The second centrifuge (600) is connected to a product discharge pipe (10) and a third material distribution pipe (11). The third material distribution pipe (11) is connected to the water-methanol rectification tower (400).

2. The synthetic system for glycine according to claim 1, wherein: The chloroacetic acid concentrated liquid feeding unit (110) includes a chloroacetic acid solution feeding pipe (111), a first evaporation concentrator (112) and a first transfer pipe (113) connected in sequence. A first feeding valve (114) is provided on the first transfer pipe (113). A first densitometer (115) is provided on the first evaporation concentrator (112). The first densitometer (115) detects the concentration of the chloroacetic acid solution in the first evaporation concentrator (112) and transmits this information to the DCS. When the concentration of the chloroacetic acid solution reaches a preset value, the DCS controls to open the first feeding valve (114).

3. The synthetic system for glycine according to claim 2, wherein: A second feeding valve (116) is provided on the chloroacetic acid solution feeding pipe (111).

4. The synthetic system for glycine according to claim 3, wherein: A first intermediate storage tank (117) and a third feeding valve (118) are also provided in sequence on the first transfer pipe (113).

5. The synthetic system for glycine according to claim 1, wherein: The hexamine concentrate feeding unit (120) includes a hexamine solution feeding pipe (121), a second evaporation concentrator (122), and a second transfer pipe (123) connected in sequence. A fourth feeding valve (124) is provided on the second transfer pipe (123), and a second densitometer (125) is provided on the second evaporation concentrator (122). The second densitometer (125) detects the concentration of the hexamine solution in the second evaporation concentrator (122) and transmits this information to the DCS. When the concentration of the hexamine solution reaches a preset value, the DCS controls the opening of the fourth feeding valve (124).

6. The synthetic system for glycine according to claim 5, characterized in that: A fifth feeding valve (126) is provided on the hexamine solution feeding pipe (121).

7. The synthetic system for glycine according to claim 6, wherein: A second intermediate tank (127) and a sixth feeding valve (128) are further provided on the second transfer pipe (123) in sequence.

8. The synthesis system for glycine according to claim 1, characterized in that: A first transfer pump (12) is provided on the first discharge pipe (2); a second transfer pump (13) is provided on the second distribution pipe (5), a third transfer pump (14) is provided on the third distribution pipe (11), a fourth transfer pump (20) is provided on the fifth distribution pipe (23), and a water-methanol transfer pump (15) is provided on the water-methanol feeding pipe (8).

9. The synthetic system for glycine according to claim 8, wherein: A liquid ammonia feeding valve (16) and a liquid ammonia flowmeter (17) are provided on the liquid ammonia feeding pipe (1).

10. A synthesis system for glycine according to claim 9, characterized in that: A water-methanol feeding valve (18) and a water-methanol flowmeter (19) are further provided on the water-methanol feeding pipe (8).

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