Methionine crystallizer
By combining cyanohydrin reaction tower, stripping tower, hydrolysis tower and crystallization tower, and optimizing catalyst use and mother liquor circulation, the problems of high catalyst consumption, many by-products and large pollutant emissions in traditional methionine preparation have been solved, and efficient methionine production has been achieved.
Patent Information
- Application Number
- CN202520029539.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-07
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2035-01-07
AI Technical Summary
The traditional hydantoin process for producing methionine involves high consumption of sodium hydroxide catalyst, high byproduct production of sodium sulfate, and significant pollution emissions and pollution control pressures.
A combined unit consisting of a cyanohydrin reaction tower, a stripping tower, a hydrolysis tower, and a crystallization tower is used. By recycling the mother liquor and optimizing the catalyst, catalyst consumption and byproduct generation are reduced, thus achieving the recycling of methionine mother liquor.
This reduces catalyst consumption, decreases the formation of sodium sulfate as a byproduct, improves raw material utilization, reduces pollutant emissions, and increases methionine production.
Smart Images
Figure CN223818211U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of chemical raw material production technology, and more specifically, to a methionine crystallizer. Background Technology
[0002] Methionine is a nonpolar α-amino acid widely used in the feed and pharmaceutical industries. Currently, the hydantoin process is commonly used to prepare methionine, which involves first preparing a solution containing methionine, and then crystallizing the methionine solution to obtain solid methionine.
[0003] However, in the current hydantoin process for producing methionine, hydantoin is often used as a raw material. Methionine is produced through steps such as alkali absorption followed by hydrolysis using HCN. However, the traditional hydantoin hydrolysis process for methionine production has several problems, such as high consumption of sodium hydroxide catalyst, high sodium sulfate byproduct production, and significant pollutant emissions and pollution control pressures. Therefore, it has shortcomings. Utility Model Content
[0004] To overcome the above shortcomings, this invention provides a methionine crystallizer that can reduce catalyst consumption and sodium sulfate by-product production, thereby achieving sodium reduction, improving raw material utilization, reducing resource waste, and reducing pollutant emissions.
[0005] This application is implemented as follows:
[0006] A cyanohydrin reaction tower is fixedly connected to a stripping tower, the bottom outlet of the stripping tower is fixedly connected to a hydrolysis tower, the bottom outlet of the hydrolysis tower is fixedly connected to a crystallization tower, and a mother liquor circulation pipe is provided on the hydrolysis tower. One end of the mother liquor circulation pipe is fixedly connected to the outlet of the hydrolysis tower, and the other end of the mother liquor circulation pipe is fixedly connected to the inlet of the hydrolysis tower.
[0007] In one embodiment of this application, the stripping tower is a distillation stripping tower, the inlet of the stripping tower is fixedly connected to the outlet of the cyanohydrin reaction tower, and the outlet of the stripping tower is fixedly connected to the inlet of the hydrolysis tower.
[0008] In one embodiment of this application, the crystallization tower includes a tower body, a stirring element, a circulating cooling element, and a valve. The stirring element is fixedly connected to the top of the tower body, the circulating cooling element is spirally wound around the tower body, a complete crystallization chamber is opened at the bottom of the tower body, and the valve is located at the top of the complete crystallization chamber.
[0009] In one embodiment of this application, the tower body is provided with an inlet pipe, an outlet pipe and a discharge port, the inlet pipe and the discharge port are located on the side wall of the tower body, the height of the discharge port is lower than that of the inlet pipe, the outlet pipe is fixedly connected to the complete crystallization chamber, and a catalyst inlet pipe is provided at the bottom end of the tower body.
[0010] In one embodiment of this application, a crystallization circulation pipe is provided on the tower body, one end of the crystallization circulation pipe is fixedly connected to the outlet, and the other end of the crystallization circulation pipe is fixedly connected to the inlet pipe.
[0011] In one embodiment of this application, the stirring component includes a rotary motor and a stirrer, the rotary motor being fixedly connected to the top of the tower body, and the stirrer being fixedly connected to the output end of the rotary motor.
[0012] In one embodiment of this application, the circulating cooling element is a spiral cooling pipe, and the spiral cooling pipe is externally connected to a cooling heat exchanger.
[0013] The beneficial effects of this application are as follows: During the production process, TPMA and HCN raw materials are first placed in a cyanohydrin reaction tower to obtain a cyanohydrin mixture. Then, the cyanohydrin mixture is purified by distillation in a stripping tower to obtain a purified cyanohydrin solvent. The purified cyanohydrin solvent is added to a hydrolysis tower, where sodium carbonate is used as a catalyst to cause the cyanohydrin to undergo a hydrolysis reaction, generating methionine mother liquor. Unreacted cyanohydrin is circulated back into the hydrolysis tower through a mother liquor circulation pipe, allowing the reaction to be repeated multiple times until the reaction is complete, resulting in a methionine mother liquor. At this point, the consumption of sodium carbonate catalyst is relatively small, and the generation of the byproduct sodium sulfate is also relatively small. The methionine mother liquor generated in the hydrolysis tower enters... Inside the crystallization tower, the methionine mother liquor undergoes a catalytic crystallization reaction. The methionine mother liquor can be recycled back into the crystallization tower to ensure complete crystallization. This device can recycle incompletely reacted cyanohydrin and incompletely crystallized methionine mother liquor, reducing catalyst consumption and the production of the byproduct sodium sulfate. This achieves sodium reduction in the methionine production process, improves the utilization rate of cyanohydrin and methionine mother liquor, thereby increasing product productivity, reducing pollutant emissions, and addressing the problems of high catalyst consumption, high sodium sulfate byproduct production, and significant pollutant emissions and pollution control pressure in existing methionine preparation technologies. Attached Figure Description
[0014] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.
[0015] Figure 1 A schematic diagram of the structure of a methionine crystallizer is provided in this application embodiment;
[0016] Figure 2 A schematic diagram of the crystallization tower is provided for the embodiments of this application;
[0017] Figure 3 A schematic diagram of the structure of the circulating cooling component is provided for the embodiments of this application;
[0018] Figure 4 A flowchart illustrating the process of methionine crystallization for embodiments of this application is provided;
[0019] In the diagram: 1-Cyanohydrin reaction tower; 2-Stripping tower; 3-Hydrolysis tower; 4-Crystallization tower; 41-Tower body; 42-Agitator; 421-Rotating motor; 422-Agitator; 43-Circulating cooling components; 44-Valve; 45-Complete crystallization chamber; 46-Inlet pipe; 47-Outlet pipe; 48-Discharge port; 49-Crystallization circulation pipe; 5-Mother liquor circulation pipe; Detailed Implementation
[0020] The following detailed description, in conjunction with the accompanying drawings, outlines some embodiments of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0021] like Figures 1-4As shown, a methionine crystallizer according to an embodiment of this application includes: a cyanohydrin reaction tower 1, a stripping tower 2 fixedly connected to the cyanohydrin reaction tower 1, a hydrolysis tower 3 fixedly connected to the bottom outlet of the stripping tower 2, a crystallization tower 4 fixedly connected to the bottom outlet of the hydrolysis tower 3, a mother liquor circulation pipe 5 provided on the hydrolysis tower 3, one end of the mother liquor circulation pipe 5 fixedly connected to the outlet of the hydrolysis tower 3, and the other end of the mother liquor circulation pipe 5 fixedly connected to the inlet of the hydrolysis tower 3. In the production process, TPMA and HCN raw materials are first placed in cyanohydrin reaction tower 1 to obtain a cyanohydrin mixture. Then, the cyanohydrin mixture is distilled through stripping tower 2 to obtain purified cyanohydrin solvent. The purified cyanohydrin solvent is added to hydrolysis tower 3, using sodium carbonate as a catalyst to cause the cyanohydrin to undergo a hydrolysis reaction. At this time, methionine mother liquor is generated. The unreacted cyanohydrin is circulated back into hydrolysis tower 3 through mother liquor circulation pipe 5, allowing the reaction to be repeated multiple times until the reaction is complete, forming methionine mother liquor. At this time, the consumption of sodium carbonate catalyst is relatively small, and the byproduct sodium sulfate is generated in small amounts. The methionine mother liquor generated in hydrolysis tower 3 enters the crystallization stage. Inside tower 4, the methionine mother liquor undergoes a catalytic crystallization reaction, and the methionine mother liquor can be circulated back into tower 4 to ensure complete crystallization. This device can recycle incompletely reacted cyanohydrin and incompletely crystallized methionine mother liquor, reducing catalyst consumption and the production of byproduct sodium sulfate. This achieves the sodium reduction requirement in the methionine production process, improves the utilization rate of cyanohydrin and methionine mother liquor, thereby increasing product productivity, reducing pollutant emissions, and improving the problems of high catalyst consumption, high sodium sulfate byproduct production, and high pollutant emissions and pollution control pressure in the existing technology for methionine preparation.
[0022] like Figure 1 As shown, stripping tower 2 is a distillation stripping tower. The inlet of stripping tower 2 is fixedly connected to the outlet of cyanohydrin reaction tower 1, and the outlet of stripping tower 2 is fixedly connected to the inlet of hydrolysis tower 3. Stripping tower 2 is used to purify cyanohydrin, thereby reducing the amount of byproducts generated during cyanohydrin hydrolysis.
[0023] like Figure 2As shown, the crystallization tower 4 includes a tower body 41, a stirrer 42, a circulating cooler 43, and a valve 44. The stirrer 42 is fixedly connected to the top of the tower body 41, and the circulating cooler 43 is spirally coiled inside the tower body 41. A complete crystallization chamber 45 is opened at the bottom of the tower body 41, and the valve 44 is located at the top of the complete crystallization chamber 45. The valve 44 is a solenoid valve hinged to both sides of the bottom of the tower body 41. The methionine mother liquor is placed into the tower body 41, and the stirrer 42 is started to stir the methionine mother liquor. At the same time, the circulating cooler 43 cools and lowers the temperature of the methionine mother liquor, thereby gradually crystallizing the methionine mother liquor. When the methionine mother liquor is completely crystallized, the valve 44 is opened to allow the crystals to enter the complete crystallization chamber 45 for collection. After collection, the crystals proceed to the next process flow, including water washing and purification of the methionine crystals. The tower body 41 is provided with an inlet pipe 46, an outlet pipe 47, and a discharge port 48. The inlet pipe 46 and the discharge port 48 are located on the side wall of the tower body 41. The height of the discharge port 48 is lower than that of the inlet pipe 46. The outlet pipe 47 is fixedly connected to the complete crystallization chamber 45. A catalyst inlet pipe is provided at the bottom of the tower body 41. A crystallization circulation pipe 49 is provided on the tower body 41. One end of the crystallization circulation pipe 49 is fixedly connected to the discharge port 48, and the other end of the crystallization circulation pipe 49 is fixedly connected to the inlet pipe 46. When the methionine mother liquor crystallizes inside tower 41, the methionine crystals automatically sink to the bottom of tower 41, resulting in a lower methionine content in the upper layer of methionine mother liquor. At this time, the upper layer of methionine mother liquor is not easy to crystallize and is easily regarded as waste liquid and directly discharged from tower 41. However, through the crystallization circulation pipe 49, the upper layer of methionine mother liquor with a lower concentration from the previous cycle re-enters the inlet pipe 46. After mixing with the methionine mother liquor from the next cycle, the upper layer of methionine mother liquor with a lower concentration from the previous cycle re-enters tower 41 for recrystallization. This avoids the lower concentration upper layer of methionine mother liquor being discharged from tower 41 as waste liquid, improves the utilization rate of methionine mother liquor, and thus increases the yield of methionine crystals.
[0024] Furthermore, the stirring component 42 includes a rotary motor 421 and a stirrer 422. The rotary motor 421 is fixedly connected to the top of the tower body 41, and the stirrer 422 is fixedly connected to the output end of the rotary motor 421. By starting the rotary motor 421, the stirrer 422 is driven to rotate, thereby accelerating the crystallization rate of the methionine mother liquor.
[0025] like Figure 3 As shown, the circulating cooling component 43 is a spiral cooling pipe, and a cooling heat exchanger is connected to the outside of the spiral cooling pipe. By continuously exchanging heat through the spiral cooling pipe, the temperature of the methionine mother liquor is lowered, thereby accelerating crystallization.
[0026] In summary, the working principle of a methionine crystallizer according to this utility model embodiment is as follows: During use and manufacturing, TPMA and HCN raw materials are first placed in a cyanohydrin reaction tower 1 to obtain a cyanohydrin mixture. Then, the cyanohydrin mixture is distilled through a stripping tower 2 to obtain purified cyanohydrin solvent. The purified cyanohydrin solvent is added to a hydrolysis tower 3, using sodium carbonate as a catalyst to cause the cyanohydrin to undergo a hydrolysis reaction, generating methionine mother liquor. Unreacted cyanohydrin is circulated back into the hydrolysis tower 3 through a mother liquor circulation pipe 5, allowing the reaction to repeat repeatedly until complete, resulting in a methionine mother liquor. At this point, the consumption of sodium carbonate catalyst is relatively small, and the generation of the byproduct sodium sulfate is minimal. The methionine mother liquor generated in the hydrolysis tower 3 enters the crystallization tower 4. The stirring element 42 is activated to stir the methionine mother liquor, while the circulating cooling element 43 cools and lowers the temperature, causing the methionine mother liquor to gradually crystallize. Simultaneously, the lower-concentration upper layer of methionine mother liquor re-enters the inlet pipe 4 through the crystallization circulation pipe 49. Within section 6, the lower-concentration upper layer of methionine mother liquor is mixed with the methionine mother liquor that directly enters the inlet pipe 46 and then re-enters the tower body 41 for recrystallization. This avoids the lower-concentration upper layer of methionine mother liquor being discharged from the tower body 41 as waste liquid, improving the utilization rate of the methionine mother liquor and thus increasing the yield of methionine crystals. After the methionine mother liquor is completely crystallized, valve 44 is opened to allow the crystals to enter the complete crystallization chamber 45 for collection. After collection, it enters the next process flow for operations such as water washing and purification of the methionine crystals. This device can recycle incompletely reacted cyanohydrin and incompletely crystallized methionine mother liquor, reducing catalyst consumption and the production of by-product sodium sulfate. It meets the sodium reduction requirements in the methionine production process, improves the utilization rate of cyanohydrin and methionine mother liquor, thereby increasing product productivity, reducing pollutant emissions, and improving the problems of high catalyst consumption, high sodium sulfate by-product production, high pollutant emissions, and high pollution control pressure in the existing technology for methionine preparation.
[0027] The above are merely embodiments of this application and are not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application. It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
Claims
1. A methionine crystallizer, characterized in that, include: A cyanohydrin reaction tower (1) is fixedly connected to a stripping tower (2). The bottom outlet of the stripping tower (2) is fixedly connected to a hydrolysis tower (3). The bottom outlet of the hydrolysis tower (3) is fixedly connected to a crystallization tower (4). A mother liquor circulation pipe (5) is provided on the hydrolysis tower (3). One end of the mother liquor circulation pipe (5) is fixedly connected to the outlet of the hydrolysis tower (3), and the other end of the mother liquor circulation pipe (5) is fixedly connected to the inlet of the hydrolysis tower (3).
2. The methionine crystallizer according to claim 1, characterized in that, The stripping tower (2) is a distillation stripping tower. The inlet of the stripping tower (2) is fixedly connected to the outlet of the cyanohydrin reaction tower (1), and the outlet of the stripping tower (2) is fixedly connected to the inlet of the hydrolysis tower (3).
3. The methionine crystallizer according to claim 1, characterized in that, The crystallization tower (4) includes a tower body (41), a stirring element (42), a circulating cooling element (43), and a valve (44). The stirring element (42) is fixedly connected to the top of the tower body (41), and the circulating cooling element (43) is spirally coiled inside the tower body (41). A complete crystallization chamber (45) is opened at the bottom of the tower body (41), and the valve (44) is located at the top of the complete crystallization chamber (45).
4. A methionine crystallizer according to claim 3, characterized in that, The tower body (41) is provided with an inlet pipe (46), an outlet pipe (47) and a discharge port (48). The inlet pipe (46) and the discharge port (48) are located on the side wall of the tower body (41). The height of the discharge port (48) is lower than that of the inlet pipe (46). The outlet pipe (47) is fixedly connected to the complete crystallization chamber (45). The bottom end of the tower body (41) is provided with a catalyst inlet pipe.
5. A methionine crystallizer according to claim 4, characterized in that, The tower body (41) is provided with a crystallization circulation pipe (49), one end of which is fixedly connected to the outlet (48), and the other end of which is fixedly connected to the inlet pipe (46).
6. A methionine crystallizer according to claim 3, characterized in that, The stirring component (42) includes a rotating motor (421) and a stirrer (422). The rotating motor (421) is fixedly connected to the top of the tower body (41), and the stirrer (422) is fixedly connected to the output end of the rotating motor (421).
7. A methionine crystallizer according to claim 3, characterized in that, The circulating cooling component (43) is a spiral cooling pipe, and a cooling heat exchanger is connected to the outside of the spiral cooling pipe.