Alkyl dimethyl betaine production device

Abstract

The invention discloses a device for producing alkyl dimethyl betaine. The device comprises a premixing chamber, a first reaction zone, a pressure retention zone, a detection zone and a second reaction zone which are communicated in sequence, the premixing chamber is provided with a return port for feeding sodium chloroacetate and dodecyl tertiary amine, a discharge port and two feed ports, and the discharge port is communicated with the first reaction zone for quaternization reaction; the pressure retention area comprises a first circuitous pipeline connected with the first reaction area and the detection area and a pressure regulating valve arranged on the first circuitous pipeline; the detection area is provided with a standing tank, the liquid inlet end of the standing tank is communicated with the first circuitous pipeline, two liquid outlet ends of the standing tank are respectively connected to the second reaction area and the material return port through a first control valve and a second control valve, and meanwhile, a chloride ion detector is arranged in the standing tank. And the second reaction zone is provided with a liquid caustic soda inlet for hydrolysis reaction of residual sodium chloroacetate and liquid caustic soda. According to the device, continuous production of a pipeline is realized, feed liquid can be returned when quaternization of dodecylamine is insufficient, reaction is performed after reaction parameters are adjusted, the high quaternization degree is ensured, and the product percent of pass is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical reaction devices, and particularly to a production device for alkyl dimethyl betaine. Background Art

[0002] Betaine surfactants, as the amphoteric surfactants with the largest market share globally, are widely used in multiple industries such as personal care, household care, textile printing and dyeing, papermaking, and oil extraction. Especially in personal care products, betaine surfactants, as mild surfactants, can provide excellent softness and antistatic effects and are deeply loved by consumers. Among them, alkyl dimethyl betaine is prepared by quaternization reaction of alkyl tertiary amine and sodium chloroacetate. Currently, industrial production of alkyl dimethyl betaine generally uses batch stirred reaction kettles, and the technological steps are divided into two stages: reacting alkyl tertiary amine with excessive sodium chloroacetate to obtain alkyl dimethyl betaine, and hydrolyzing the product to remove excessive sodium chloroacetate.

[0003] Currently, industrial production of alkyl dimethyl betaine uses batch reaction kettles. Firstly, each reaction kettle operates independently during the reaction, and the feeding, heating, stirring, and reaction time of each batch of reactions need to be calculated and controlled independently, with cumbersome operation and calculation. Secondly, when transferring intermediate liquid materials between reaction kettles, the transportation pipelines outside the reaction kettles are difficult to ensure the stability of the intermediate liquid materials, which easily affects the purity and quality of the products. Moreover, due to the large volume of the reaction kettle and the rapid change of heat load, the heat transfer efficiency may be uneven, and there may be certain lags or unevenness in temperature control. The instability of temperature not only affects the reaction rate and selectivity but also may cause local overheating or overcooling, resulting in differences in the quality of the final product. Summary of the Invention

[0004] The purpose of the present invention is to provide a production device for alkyl dimethyl betaine, which can carry out pipeline continuous production, and when the quaternization of dodecyl tertiary amine is insufficient, the feed liquid can be recycled, the quaternization reaction parameters can be adjusted and then reacted again, which can ensure a high degree of quaternization of dodecyl tertiary amine, thereby improving the qualification rate of subsequent products.

[0005] To achieve the above purpose, the present invention provides a production device for alkyl dimethyl betaine, including:

[0006] A pre-mixing chamber, a first reaction zone, a pressure retention zone, a detection zone, and a second reaction zone connected in sequence;

[0007] The pre-mixing chamber has a first feed port, a second feed port, a return port, and a discharge port. The first feed port and the second feed port are respectively used for feeding sodium chloroacetate and dodecyl tertiary amine, and the discharge port is connected to the first reaction zone;

[0008] The first reaction zone is used for the quaternization reaction of sodium chloroacetate and dodecyl tertiary amine;

[0009] The pressure retention zone includes a first circuitous pipeline and a pressure regulating valve arranged on the first circuitous pipeline. The two ends of the first circuitous pipeline are respectively communicated with the first reaction zone and the detection zone;

[0010] The detection zone includes a static tank. The liquid inlet end of the static tank is communicated with the first circuitous pipeline. The static tank has two liquid outlet ends. One liquid outlet end of the static tank is communicated with the second reaction zone and is provided with a first control valve at the communication position. The other liquid outlet end of the static tank is communicated with the return port and is provided with a second control valve at the communication position. A chloride ion detector is arranged in the static tank;

[0011] The second reaction zone has a liquid caustic inlet, and the second reaction zone is used for the hydrolysis reaction of the remaining sodium chloroacetate and liquid caustic.

[0012] Further, a secondary mixing chamber and a buffer section are communicated between the premixing chamber and the first reaction zone, and the secondary mixing chamber and the buffer section are arranged in sequence along the liquid flow direction.

[0013] Furthermore, a spray head is arranged at the discharge port.

[0014] Furthermore, the first reaction zone includes a pipe body and fillers filled in the pipe body. The inner diameter of the pipe body is larger than the inner diameter of the buffer section, and the pipe body is smoothly connected with the buffer section.

[0015] Further, the first circuitous pipeline includes a plurality of U-shaped pipes arranged side by side. One end of the U-shaped pipe close to the first reaction zone is connected with the liquid outlet end of the first reaction zone, and one end of the U-shaped pipe close to the static tank is connected with the liquid inlet end of the static tank. The two ends of the remaining U-shaped pipes are respectively connected with the ends of the adjacent U-shaped pipes, and the pressure regulating valve is arranged on the U-shaped pipe close to the static tank.

[0016] Furthermore, a flow dividing plate is also arranged in the first circuitous pipeline, and the pressure regulating valve and the flow dividing plate are arranged in sequence along the liquid flow direction on the first circuitous pipeline.

[0017] Further, the detection zone further includes a buffer tank, and the buffer tank is communicated between the second control valve and the return port.

[0018] Further, the second reaction zone includes a second circuitous pipeline and a plurality of mixing devices. The plurality of mixing devices are arranged at intervals on the second circuitous pipeline. One end of the second circuitous pipeline is connected to the first control valve, and the other end of the second circuitous pipeline is connected to a discharge valve. The liquid caustic soda inlet is opened on the second circuitous pipeline, and the liquid caustic soda inlet and the mixing device close to the first control valve are arranged in sequence in the liquid flow direction.

[0019] Further, the alkyl dimethyl betaine production device further includes a control component. A liquid level sensor is further arranged in the static tank. The control component is electrically connected to the chloride ion detector, the pressure regulating valve, the first control valve, the second control valve and the liquid level sensor.

[0020] Compared with the prior art, the alkyl dimethyl betaine production device according to the embodiment of the present invention has the beneficial effects that: through the sequential connection of the pre-mixing chamber, the first reaction zone, the pressure retention zone, the detection zone and the second reaction zone, the continuity of the reaction process is realized, and the product quality fluctuation caused by batch production in the traditional batch reactor is avoided; the pressure regulating valve arranged on the first circuitous pipeline can effectively ensure the hydraulic stability in the first circuitous pipeline, extend the residence time of dodecyl dimethyl amine and sodium chloroacetate in the first circuitous pipeline, enable the liquid materials to be fully mixed, and enable dodecyl dimethyl amine to be fully quaternized in the first circuitous pipeline, reduce the reaction instability or side reactions caused by pressure fluctuations, and ensure the smooth progress of the reaction process; a chloride ion detector is equipped in the static tank. The liquid materials after the quaternization reaction are input into the static tank for static settlement, and then the liquid materials are detected by the chloride ion detector. If the quaternization is too low, it will be reflected by the free chloride ions, and then reflected on the chloride ion detector. The static tank and the chloride ion detector can perform sectional detection of chloride ions in the liquid materials. First, the liquid materials are placed in the static tank for static settlement, which can avoid the influence of the moving liquid materials on the detection of the chloride ion detector and ensure the reliability of the chloride ion detection structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic structural diagram of the alkyl dimethyl betaine production device according to the embodiment of the present invention;

[0022] In the figure, 1, pre-mixing chamber; 11, first feed inlet; 12, second feed inlet; 13, return port; 14, discharge port;

[0023] 2, first reaction zone; 21, pipe body; 22, packing;

[0024] 3, pressure retention zone; 31, first circuitous pipeline; 311, U-shaped pipe; 32, pressure regulating valve; 33, flow dividing plate;

[0025] 4. Detection area; 41. Static tank; 42. First control valve; 43. Second control valve; 44. Buffer tank;

[0026] 5. Second reaction area; 51. Second circuitous pipeline; 511. Liquid alkali inlet; 52. Mixing device;

[0027] 6. Secondary mixing chamber;

[0028] 7. Buffer section. Specific embodiments

[0029] The following combines the drawings and embodiments to further describe in detail the specific embodiments of the present invention. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0030] In the description of the present invention, the terms "upper", "lower", "left", "right", "front", "rear", "inner", "outer", "lateral", "longitudinal", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, and are not used to limit that the indicated device, element or component must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present utility model. For those of ordinary skill in the art, the specific meanings of these terms in the present invention can be understood according to specific circumstances.

[0031] In the description of the present invention, the terms "provided with", "set", "connected", "placed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or there is an internal connection between two devices, elements or components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated device, element or component. Unless otherwise specified, the meaning of "plural" is two or more.

[0033] The following further illustrates the technical solutions of the present invention in combination with embodiments and drawings.

[0034] As Figure 1 shown, an alkyl dimethyl betaine production device according to an embodiment of the present invention includes:

[0035] A pre-mixing chamber 1, a first reaction area 2, a pressure retention area 3, a detection area 4, and a second reaction area 5 that are connected in sequence;

[0036] The premixing chamber 1 has a first feed inlet 11, a second feed inlet 12, a return feed port 13 and a discharge port 14. The first feed inlet 11 and the second feed inlet 12 are respectively used for feeding sodium chloroacetate and dodecyl tertiary amine, and the discharge port 14 is communicated with the first reaction zone 2;

[0037] The first reaction zone 2 is used for the quaternization reaction of sodium chloroacetate and dodecyl tertiary amine;

[0038] The pressure retention zone 3 includes a first bypass pipeline 31 and a pressure regulating valve 32 arranged on the first bypass pipeline 31. The two ends of the first bypass pipeline 31 are respectively communicated with the first reaction zone 2 and the detection zone 4;

[0039] The detection zone 4 includes a static tank 41. The liquid inlet end of the static tank 41 is communicated with the first bypass pipeline 31. The static tank 41 has two liquid outlet ends. One liquid outlet end of the static tank 41 is communicated with the second reaction zone 5 and a first control valve 42 is arranged at the communication position. The other liquid outlet end of the static tank 41 is communicated with the return feed port 13 and a second control valve 43 is arranged at the communication position. A chloride ion detector is arranged in the static tank 41;

[0040] The second reaction zone 5 has a liquid caustic inlet 511. The second reaction zone 5 is used for the hydrolysis reaction of the remaining sodium chloroacetate and liquid caustic (the chloride ion detector is not shown in the attached drawings of the specification).

[0041] Based on the above technical solution, by connecting the premixing chamber 1, the first reaction zone 2, the pressure retention zone 3, the detection zone 4 and the second reaction zone 5 in sequence, the continuity of the reaction process is realized, and the product quality fluctuation caused by batch production in the traditional batch reactor is avoided; the pressure regulating valve 32 arranged on the first bypass pipeline 31 can effectively ensure the hydraulic stability in the first bypass pipeline 31, extend the residence time of dodecyl tertiary amine and sodium chloroacetate in the first bypass pipeline 31, make the liquid materials fully mixed, and enable dodecyl tertiary amine to be fully quaternized in the first bypass pipeline 31, reduce the reaction instability or side reactions caused by pressure fluctuation, and ensure the smooth progress of the reaction process; a chloride ion detector is equipped in the static tank 41. The liquid material after the quaternization reaction is input into the static tank 41 for static settlement, and then the liquid material is detected by the chloride ion detector. If the quaternization is too low, it will be reflected by the free chloride ions, thus being reflected on the chloride ion detector. The static tank 41 and the chloride ion detector can detect the chloride ions in the liquid material in a segmented manner. First, the liquid material is placed in the static tank 41 for static settlement, which can avoid the influence of the moving liquid material on the detection of the chloride ion detector and ensure the reliability of the chloride ion detection structure.

[0042] Preferably, a secondary mixing chamber 6 and a buffer section 7 are communicated between the premixing chamber 1 and the first reaction zone 2, and the secondary mixing chamber 6 and the buffer section 7 are arranged in sequence along the liquid flow direction.

[0043] More preferably, a spray head (not shown in the attached drawings of the specification) is provided at the discharge port 14.

[0044] Based on the above technical solution, sodium chloroacetate enters the pre-mixing chamber 1 through the first feed port 11, and dodecylamine enters the pre-mixing chamber 1 through the second feed port 12. The insufficiently reacted sodium chloroacetate and dodecylamine flow back into the pre-mixing chamber 1 through the return port 13. After preliminary mixing in the pre-mixing chamber 1, the liquid material is sprayed into the secondary mixing chamber 6 through the spray head at the discharge port 14. After mixing in the secondary mixing chamber 6, the flow rate of the liquid material flowing into the first reaction zone 2 is reduced through the buffer section 7.

[0045] The spray head can atomize and eject the mixed liquid material in the pre-mixing chamber 1, so that the liquid forms fine droplets when entering the secondary mixing chamber 6, thereby enabling more sufficient and uniform mixing of sodium chloroacetate and dodecylamine and reducing the phenomenon of uneven local concentration. After sufficient mixing in the secondary mixing chamber 6, the flow rate of the liquid material is further reduced through the buffer section 7, which helps to smoothly and stably feed the uniformly mixed raw materials into the first reaction zone 2. The buffer section 7 reduces the flow rate of the liquid material entering the first reaction zone 2, reduces the sudden change in flow rate and pressure, and thus reduces the local temperature and pressure fluctuations caused by the sudden change in flow rate or impact, ensuring the consistency of the reaction conditions.

[0046] More preferably, the first reaction zone 2 includes a pipe body 21 and a filler 22 filled in the pipe body 21. The inner diameter of the pipe body 21 is larger than the inner diameter of the buffer section 7, and the pipe body 21 is smoothly connected to the buffer section 7.

[0047] The larger inner diameter of the pipe body 21 than that of the buffer section 7 enables the fluid to enter the first reaction zone 2 smoothly from the buffer section 7. Due to the increase in the cross-sectional area of the flow channel, the flow rate decreases, which helps the liquid material to contact and mix uniformly and sufficiently in the filler 22, avoiding fluid concentration; the larger inner diameter of the pipe body 21 and the structure of the filler 22 can make the reaction liquid stay in the first reaction zone 2 for a longer time, make full use of the surface area of the filler 22, promote the contact and chemical reaction between sodium chloroacetate and dodecylamine, and improve the reaction conversion rate; the smooth transition between the pipe body 21 and the buffer section 7 avoids sudden cross-sectional changes, reduces local turbulence, flow dead ends and pressure losses, and ensures the stable operation of the reaction process.

[0048] Preferably, the first bypass pipeline 31 includes a plurality of U-shaped pipes 311 arranged side by side. One end of the U-shaped pipe 311 close to the first reaction zone 2 is connected to the liquid outlet end of the first reaction zone 2, one end of the U-shaped pipe 311 close to the static tank 41 is connected to the liquid inlet end of the static tank 41, and the two ends of the remaining U-shaped pipes 311 are respectively connected to the ends of the adjacent U-shaped pipes 311. The pressure regulating valve 32 is arranged on the U-shaped pipe 311 close to the static tank 41.

[0049] Specifically, the U-shaped tube 311 near the stationary tank 41 is inverted, with both ends of the U-shaped tube 311 facing downward. The pressure regulating valve 32 is arranged at the top of the U-shaped tube 311. A plurality of U-shaped tubes 311 are defined to form a serpentine tube, and the plane where the serpentine tube is located is parallel to the vertical direction.

[0050] Arranging a plurality of U-shaped tubes 311 into a serpentine tube causes a certain degree of backmixing of the liquid material in the U-shaped tubes 311, which helps to achieve uniform mixing between the reactants, can effectively avoid problems such as excessive local concentration or uneven temperature of the liquid material, and further improve the reaction efficiency and product quality.

[0051] More preferably, a flow dividing plate 33 is further provided in the first bypass pipeline 31, and the pressure regulating valve 32 and the flow dividing plate 33 are sequentially arranged on the first bypass pipeline 31 along the liquid flow direction.

[0052] The flow dividing plate 33 functions to divide the flow and divide the pressure in the first bypass pipeline 31. By arranging the flow dividing plate 33 behind the pressure regulating valve 32, the flow dividing plate 33 can break up the flow of the liquid material, causing the liquid material to form a plurality of fine flow streams after passing through the flow dividing plate 33, enabling the liquid material to be uniformly mixed; and the flow dividing plate 33 has a blocking effect on the liquid material, prolonging the residence time of the liquid material in the pipeline, which is beneficial to the full progress of the quaternization reaction.

[0053] Preferably, the detection area 4 further includes a buffer tank 44, and the buffer tank 44 is connected between the second control valve 43 and the return port 13.

[0054] The buffer tank 44, as an intermediate storage unit, can make the adjustment of the liquid material flow rate and state in the detection area 4 more flexible. Combined with the second control valve 43, the control of the liquid material reflux can be more precisely achieved.

[0055] Preferably, the second reaction area 5 includes a second bypass pipeline 51 and a plurality of mixing devices 52. The plurality of mixing devices 52 are arranged at intervals on the second bypass pipeline 51. One end of the second bypass pipeline 51 is connected to the first control valve 42, and the other end of the second bypass pipeline 51 is connected with a discharge valve. The liquid caustic soda inlet 511 is opened on the second bypass pipeline 51, and the liquid caustic soda inlet 511 and the mixing device 52 near the first control valve 42 are sequentially arranged along the liquid flow direction.

[0056] Arranging a plurality of mixing devices 52 at intervals along the liquid flow direction in the second reaction area 5 can effectively promote the full mixing of the reactants (including sodium chloroacetate previously entering from the first control valve 42 and the liquid caustic soda subsequently introduced through the liquid caustic soda inlet 511) entering the pipeline, ensuring the uniform distribution of the reactants throughout the reaction process, thereby improving the conversion efficiency of the hydrolysis reaction and the product quality; the design of the second bypass pipeline 51 prolongs the residence time of the material in the reaction area, giving the reactants sufficient time for full reaction, which is beneficial to the completion of the reaction and the inhibition of side reactions.

[0057] Preferably, the alkyl dimethyl betaine production device further includes a control component. A liquid level sensor is also provided in the static tank 41. The control component is electrically connected to the chloride ion detector, the pressure regulating valve 32, the first control valve 42, the second control valve 43, and the liquid level sensor (the liquid level sensor is not shown in the accompanying drawings of the specification).

[0058] Specifically, a first heating device is provided on the outer peripheral wall of the pipe body 21, a second heating device is provided on the outer peripheral wall of the first bypass pipeline 31, and a third heating device is provided on the outer peripheral wall of the second bypass pipeline 51. The control component is electrically connected to the first heating device, the second heating device, and the third heating device (the first heating device, the second heating device, and the third heating device are not shown in the accompanying drawings of the specification).

[0059] The control component is configured to: when the liquid material is filled into the static tank 41 until the liquid level reaches the preset position of the liquid level sensor, close the pressure regulating valve 32. After the liquid material in the static tank 41 stands for a period of time, start the chloride ion detector to detect the chloride ion concentration in the static tank 41, and judge the quaternization degree of the liquid material through the chloride ion concentration. If the quaternization degree meets the standard, open the first control valve 42, and the liquid material in the static tank 41 flows into the second bypass pipeline 51. If the quaternization degree does not meet the standard, open the second control valve 43, and the liquid material in the static tank 41 flows into the buffer tank 44, and then returns to the premixing chamber 1 for re - quaternization reaction, and adjust the output temperature of the first heating device, the second heating device, and the flow - through pressure of the pressure regulating valve 32 to make the quaternization reaction more complete.

[0060] In summary, the embodiment of the present invention provides an alkyl dimethyl betaine production device. Through the sequential connection of the premixing chamber 1, the first reaction zone 2, the pressure retention zone 3, the detection zone 4, and the second reaction zone 5, the continuity of the reaction process is realized, and the product quality fluctuation caused by batch production in the traditional batch reactor is avoided; the pressure regulating valve 32 provided on the first bypass pipeline 31 can effectively ensure the hydraulic stability in the first bypass pipeline 31, extend the residence time of dodecyl dimethyl amine and sodium chloroacetate in the first bypass pipeline 31, make the liquid material fully mixed, and enable dodecyl dimethyl amine to be fully quaternized in the first bypass pipeline 31, reduce the reaction instability or side reactions caused by pressure fluctuations, and ensure the smooth progress of the reaction process; the static tank 41 is equipped with a chloride ion detector. The liquid material after the quaternization reaction is input into the static tank 41 for standing, and then detected by the chloride ion detector. If the quaternization is too low, it will be reflected by the free chloride ions, thus being reflected on the chloride ion detector. The static tank 41 and the chloride ion detector can perform sectional detection of chloride ions in the liquid material. First, the liquid material is placed in the static tank 41 for standing, which can avoid the influence of the moving liquid material on the detection of the chloride ion detector and ensure the reliability of the chloride ion detection result.

[0061] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and substitutions can be made, and these improvements and substitutions should also be regarded as the protection scope of the present invention.

Claims

1. An alkyl dimethyl betaine production device, characterized in that, include: A premixing chamber (1), a first reaction zone (2), a pressure retention zone (3), a detection zone (4) and a second reaction zone (5) connected in sequence; The premixing chamber (1) has a first feed port (11), a second feed port (12), a return port (13) and a discharge port (14); the first feed port (11) and the second feed port (12) are used to feed sodium chloroacetate and dodecaned tertiary amine, respectively; and the discharge port (14) is connected to the first reaction zone (2); The first reaction zone (2) is used for quaternization reaction of sodium chloroacetate and dodecyl tertiary amine; The pressure retention zone (3) comprises a first detour pipeline (31) and a pressure regulating valve (32) arranged on the first detour pipeline (31), and the two ends of the first detour pipeline (31) are respectively connected to the first reaction zone (2) and the detection zone (4); The detection zone (4) comprises a stationary tank (41), a liquid inlet end of the stationary tank (41) is connected to the first circuitous pipeline (31), and the stationary tank (41) has two liquid outlet ends, one liquid outlet end of the stationary tank (41) is connected to the second reaction zone (5) and a first control valve (42) is provided at the connection point, and the other liquid outlet end of the stationary tank (41) is connected to the return port (13) and a second control valve (43) is provided at the connection point, and a chloride ion detector is provided in the stationary tank (41); The second reaction zone (5) has a liquid alkali inlet (511), and the second reaction zone (5) is used for hydrolysis reaction of residual sodium chloroacetate with liquid alkali.

2. The alkyl dimethyl betaine production device according to claim 1, characterized in that: A secondary mixing chamber (6) and a buffer section (7) are connected between the premixing chamber (1) and the first reaction zone (2); the secondary mixing chamber (6) and the buffer section (7) are arranged in sequence along the liquid flow direction.

3. The alkyl dimethyl betaine production device according to claim 2, characterized in that: A spray head is provided at the discharge port (14).

4. The alkyl dimethyl betaine production device according to claim 2, characterized in that: The first reaction zone (2) comprises a tube body (21) and a filler (22) filled in the tube body (21); the inner diameter of the tube body (21) is greater than the inner diameter of the buffer section (7); and the tube body (21) and the buffer section (7) are smoothly connected.

5. The alkyl dimethyl betaine production device according to claim 1, characterized in that: The first detour pipeline (31) comprises a plurality of U-shaped tubes (311) arranged side by side, one end of the U-shaped tube (311) close to the first reaction zone (2) is connected to the liquid outlet end of the first reaction zone (2), one end of the U-shaped tube (311) close to the still tank (41) is connected to the liquid inlet end of the still tank (41), and the two ends of the remaining U-shaped tubes (311) are respectively connected to the ends of the U-shaped tubes (311) adjacent thereto, and the pressure regulating valve (32) is arranged on the U-shaped tube (311) close to the still tank (41).

6. The alkyl dimethyl betaine production device according to claim 5, characterized in that: A flow divider plate (33) is also provided in the first detour pipeline (31), and the pressure regulating valve (32) and the flow divider plate (33) are arranged in sequence on the first detour pipeline (31) along the direction of liquid flow.

7. The alkyl dimethyl betaine production device according to claim 1, characterized in that: The detection area (4) further comprises a buffer tank (44), and the buffer tank (44) is connected between the second control valve (43) and the return port (13).

8. The alkyl dimethyl betaine production device according to claim 1, characterized in that: The second reaction zone (5) comprises a second detour pipeline (51) and a plurality of mixing devices (52), wherein the plurality of mixing devices (52) are arranged at intervals on the second detour pipeline (51), one end of the second detour pipeline (51) is connected to the first control valve (42), and the other end of the second detour pipeline (51) is connected to a discharge valve, and the liquid alkali inlet (511) is opened on the second detour pipeline (51), and the liquid alkali inlet (511) and the mixing device (52) close to the first control valve (42) are arranged sequentially in the direction of liquid flow.

9. The alkyl dimethyl betaine production device according to claim 1, characterized in that: It also includes a control component, and a liquid level sensor is also provided in the static tank (41). The control component is electrically connected to the chloride ion detector, the pressure regulating valve (32), the first control valve (42), the second control valve (43) and the liquid level sensor.

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