Fully-continuous synthesis device for glyphosate

Abstract

To provide a fully-continuous synthesis device for glyphosate that has high production efficiency, high and stable product quality, and low emissions of the three wastes (exhaust gas, wastewater, and solid waste).SOLUTION: A fully-continuous synthesis device for glyphosate matched to a glyphosate synthesis route is provided, in which a multistage continuous reaction system is used and seven feed pumps, four micromixers, six microchannel reactors, three stirring vessels, one buffer tank, two back pressure valves, and one continuous crystallizer are sequentially connected according to the glyphosate synthesis route.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention belongs to the fine chemical technical field, and specifically relates to a completely continuous synthesis apparatus for glyphosate. [Background technology]

[0002] Glyphosate is a highly effective, low-toxicity, broad-spectrum, non-selective herbicide and the world's largest producer of pesticide active ingredients. In China, 70% of glyphosate is produced using the alkyl ester method, which uses glycine and dimethyl phosphite as the main raw materials. This method uses methanol as the reaction solvent and reacts glycine, paraformaldehyde, and dimethyl phosphite in the presence of triethylamine as a catalyst to obtain glyphosate. The glycine method has been used to produce glyphosate for over 30 years, and industrial continuous processes such as solvent recovery, triethylamine recovery, and methyl chloride recovery have already been achieved. However, this method still requires the use of batch or continuous reactors for the reaction and crystallization processes, resulting in low production efficiency, insufficient continuity, inconsistent product quality from batch to batch, and high emissions of three wastes (exhaust gas, wastewater, and solid waste).

[0003] Patents CN111205319A, CN216630779U, CN110862413A, and CN104163832B have developed continuous reactor reactors and corresponding processes, but they require the use of a large number of reactors to meet the needs of industrial production. As a result, the production area required is large, a large number of reaction materials and solvents are used online, the process safety risks are high, and the final product glyphosate must still be crystallized and purified in the reactor, resulting in low production efficiency and inconsistent quality of each batch. Summary of the Invention

[0004] In view of the problems existing in the prior art, the object of the present invention is to provide a fully continuous glyphosate synthesis apparatus which has high production efficiency, high and stable product quality, and low discharge of three wastes (exhaust gas, wastewater, and solid waste).

[0005] The fully continuous glyphosate synthesis apparatus provided by the present invention can achieve fully continuous production from raw material input to glyphosate product by connecting matching microchannel reactors, rotary dynamic reactors, continuous kettle hydrolysis dealcoholization reactors, and continuous crystallizers according to the characteristics of the reaction process, which makes it easy to improve throughput, avoids problems such as uneven product batch quality, improves process automation control, reduces reagent usage and three wastes (exhaust gas, wastewater, and solid waste) emissions, and significantly improves product yield and quality stability and reduces production costs compared with traditional production technologies.

[0006] The glyphosate completely continuous synthesis apparatus provided by the present invention is a completely continuous chemical synthesis apparatus that is configured by connecting seven feed pumps, four micromixers, six microchannel reactors, three stirring vessels, one buffer tank, two back pressure valves, and one continuous crystallizer in sequence according to the synthesis pathway of glyphosate, and is matched to the synthesis pathway of glyphosate; The prepared first and second materials are transported to the first micro-mixer by the first pump and the second pump, respectively, and are thoroughly mixed. Then, they directly enter the first micro-channel reactor through the connecting pipe to carry out the depolymerization of paraformaldehyde. The reaction liquid flowing out of the first micro-channel reactor and the third material transported by the third pump are thoroughly mixed in the second micro-mixer, and then directly enter the second micro-channel reactor to carry out an addition reaction in the second micro-channel reactor. The reaction liquid flowing out of the second micro-channel reactor is then mixed with the third material. The fourth material enters the buffer tank through the connecting pipe, and is transported by the fourth pump to the third micro-mixer, mixed with the fifth material transported by the fifth pump, and then directly enters the third micro-channel reactor through the connecting pipe for esterification reaction. In order to promote complete conversion of the reaction raw materials, the temperature in the fourth micro-channel reactor is set slightly higher than that in the third micro-channel reactor. The reaction liquid flowing out of the fourth micro-channel reactor flows through the first back-pressure valve, and the function of the first back-pressure valve is to regulate the temperature in the third and fourth micro-channel reactors. The reaction pressure is adjusted. The reaction liquid flowing out from the first back pressure valve enters the fourth micro-mixer and is thoroughly mixed with the sixth material transported by the sixth pump, and then enters the fifth micro-channel reactor for neutralization. The reaction liquid directly enters the sixth micro-channel reactor through the connecting pipe for hydrolysis. At the same time, the temperature of the reaction liquid is increased to improve the removal efficiency of low boiling point solvents and compounds after entering the first stirring pot in the continuous kettle reactor. The liquid flowing out from the sixth micro-channel reactor enters the first stirring pot from the bottom and turns into low boiling point solvents. The reaction mixture quickly evaporates, and the volatile gas enters a condensation collector connected to the first stirred tank. The remaining reaction liquid flows up from the bottom of the first stirred tank to the top outlet, and then enters the lower part of the second stirred tank through a connecting pipeline. The produced methyl chloride and some of the solvent water are continuously removed. The remaining reaction liquid flows up from the bottom of the second stirred tank to the top outlet, and then enters the lower part of the third stirred tank through a connecting pipeline, where it undergoes hydrolysis to undergo dealcoholization for complete conversion. The reaction liquid then enters a continuous crystallizer, where the product glyphosate is precipitated as the temperature drops.

[0007] In the present invention, the first and third pumps are peristaltic pumps for transporting a slurry, and the second, fourth, fifth, sixth, and seventh pumps are plunger pumps for transporting a solution.

[0008] In the present invention, the first to fourth micro mixers are micro mixers each consisting of four diamond-shaped pipe mixing elements connected in series. As shown in FIG. 2, the cross section of the diamond-shaped pipe channel has a size of 100 μm. 2 -20mm 2 The micromixer has a circular or rectangular shape, a length of 1-100 cm, and an applicable flow rate of 1-3000 mL / min. Preferably, the length is 10-100 cm, and the applicable flow rate is 300-3000 mL / min. A micromixer with this structure can ensure uniform mixing of materials.

[0009] In the present invention, the second microchannel reactor is a rotary dynamic reactor, specifically a cylindrical cavity, as shown in Figure 3. The wall of the cylindrical cavity is a heat exchange fluid intervening layer for heat flow. A central shaft is provided within the cylindrical cavity, and a plurality of stirring blades are connected to the central shaft to enhance mass and heat transfer. The central shaft is driven by a motor and has a rotation speed of 50-500 rpm / min. The cavity is cylindrical, has a diameter of 3-60 cm, a length of 20-500 cm, and an applicable flow rate of 10-50,000 mL / min. Preferably, the diameter is 10-60 cm, the length is 100-500 cm, and the applicable flow rate is 500-50,000 mL / min. A microchannel reactor with this structure is suitable for continuous and stable operation of liquid-solid systems, and its heat exchange area is 8-10 times that of a conventional kettle reactor.

[0010] Preferably, the first, third, fourth, fifth, and sixth microchannel reactors are tubular micromixers incorporating multiple (e.g., 4-8) square mixing elements arranged sequentially along the axial direction. As shown in FIG. 4, the channel size is 2-500 mm, the length is 1-10,000 m, and the applicable flow rate is 10-50,000 mL / min. Preferably, the channel size is 50-500 mm, the length is 100-10,000 m, and the applicable flow rate is 500-50,000 mL / min. A microchannel reactor with this structure separates and then reconstitutes fluids, thereby uniformly mixing materials and avoiding the problem of reduced mass transfer efficiency due to size expansion when expanding.

[0011] Preferably, the first back pressure valve and the second back pressure valve are made of stainless steel or Hastelloy, the size of the connecting pipe is 1.6mm-20mm, and the pressure range is 0.1-2.0MPa.

[0012] Preferably, the first, second, and third stirred kettles are each equipped with a stirring blade, a low-boiling distillate outlet, a heat exchange jacket fluid inlet / outlet, and a material inlet / outlet. As shown in Figure 5, the three stirred kettles are connected in series by pipelines, enabling the flow of heat exchange fluid and materials. The inner diameter of the stirred kettles is 5-1000 cm, and the height is 5-1000 cm, preferably 100-1000 cm, and 100-1000 cm, and the material is one or a combination of glass, polytetrafluoroethylene, stainless steel, Hastelloy, tantalum, and zirconium.

[0013] Preferably, the continuous crystallizer is a tubular reactor having a mixing structure and a heat exchange jacket. As shown in FIG. 6, the tubular reactor has an S-shaped pipe, the pipe wall is a heat exchange layer for heat flow, and a plurality of spherical baffles are uniformly distributed inside the pipe. The tubular reactor has an inner diameter of 2-20 cm, a length of 1-1000 m, and an applicable flow rate of 10-5000 mL / min, preferably an inner diameter of 8-20 cm, a length of 100-1000 m, and an applicable flow rate of 200-5000 mL / min, and is made of one or a combination of glass, polytetrafluoroethylene, stainless steel, Hastelloy, tantalum, and zirconium.

[0014] In the present invention, the first material is a solution or slurry of paraformaldehyde dissolved or dispersed in a solvent, the second material is a solvent-free alkali or a solution of alkali dissolved in a solvent, the third material is a solution or slurry of glycine dissolved or dispersed in a solvent, the fourth material is an intermediate solution produced in the second microchannel reactor, the fifth material is solvent-free dimethyl phosphite or a solution of dimethyl phosphite dissolved in a solvent, and the sixth material is solvent-free acid or a solution of acid dissolved in a solvent.

[0015] Wherein, the first microchannel reactor has a temperature of 30-60°C and a reaction time of 1-9 min, the second microchannel reactor has a temperature of 45-80°C and a reaction time of 6-12 min, the third microchannel reactor has a temperature of 50-80°C and a reaction time of 1-8 min, the fourth microchannel reactor has a temperature of 60-90°C and a reaction time of 5-15 min, and the fifth microchannel reactor has a temperature of 0-30°C. , the reaction time is 0.5-3 min, the sixth microchannel reactor has a temperature of 90-190°C and a reaction time of 0.5-3 min, the first stirred tank has a temperature of 80-150°C and a reaction time of 5-40 min, the second stirred tank has a temperature of 80-150°C and a reaction time of 5-40 min, the third stirred tank has a temperature of 90-160°C and a reaction time of 5-60 min, and the continuous crystallizer has a temperature of 0-80°C and a residence time of 1-30 min.

[0016] In a fully continuous chemical synthesis system for glyphosate, a rotating dynamic reactor has been developed to ensure continuous and stable operation of the liquid-solid system. Its excellent extrusion flow effect solves the problems of poor reaction uniformity and excessive by-products caused by backmixing in traditional kettle reactors. Its heat exchange area is 8-10 times larger than that of traditional kettle reactors, ensuring consistent product yield and quality during scale-up. For liquid-liquid systems, a tubular micromixer has been developed, incorporating multiple square mixing elements arranged sequentially along multiple axes. This microchannel reactor separates and reconstitutes fluids, with the number of mixing elements equal to the 2nth power of the number of elements, resulting in exponential mixing times. This ensures consistent mixing uniformity of the materials as they scale up, avoiding the yield loss caused by reduced mass transfer efficiency due to size expansion. Finally, the efficient continuous crystallizer developed enables end-to-end continuous production from raw materials to qualified products, completing integrated glyphosate production and solving the problems of traditional kettle-based production, such as the large equipment distribution range, high energy consumption, time-consuming operation, and difficult process safety control. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a flow chart of a complete continuous chemical synthesis apparatus for glyphosate. [Figure 2] FIG. 1 is a structural schematic diagram of diamond-shaped series-connected micromixers. [Figure 3] FIG. 1 is a structural schematic diagram of a rotating dynamic reactor. [Figure 4] FIG. 1 is a structural schematic diagram of a tubular micromixer with a built-in square mixing element. [Figure 5] FIG. 1 is a structural schematic diagram of a first vessel equipped with a fraction distillation function. [Figure 6] FIG. 1 is a structural schematic diagram of a continuous crystallizer having a mixing structure and a heat exchange jacket.

[0018] In Figure 3-6, 1 - heat exchange fluid outlet, 2 - heat exchange fluid intervening layer, 3 - coaxial multi-blade agitator, 4 - heat exchange fluid inlet, 5 - motor, 6 - bottom plate, 7 - support frame, 8 - reactant outlet, 9 - reactant inlet; 10 - heat exchange fluid outlet, 11 - heat exchange fluid inlet, 12 - reactant inlet, 13 - reactant outlet, 14 - square mixing element; 15 - heat exchange fluid inlet, 16 - heat exchange fluid outlet, 17 - reactant inlet, 18 - reactant outlet, 19 - cooling fluid inlet; 20 - cooling fluid outlet, 21 - condenser, 22 - material collection tank, 23 - crystallization material outlet, 24 - heat exchange fluid outlet, 25 - heat exchange fluid inlet, 26 - crystallization material inlet, 27 - spherical baffle in the crystallizer. DETAILED DESCRIPTION OF THE INVENTION

[0019] The present invention will be described below with reference to examples and drawings, but the scope of protection of the present invention is not limited to the following examples.

[0020] Example 1 The prepared raw material 1 (paraformaldehyde 0.64 kg / L) and raw material 2 (triethylamine) were transported to mixer 1 (micromixer 1) by pump 1 and pump 2, respectively, at a flow rate ratio of 2:1 and thoroughly mixed (retention time 9 min). After mixing, they were sent directly to reactor 1 via a connected pipe, where the depolymerization reaction of paraformaldehyde was carried out at 55°C. The reaction liquid flowing out of reactor 1 and raw material 3 (glycine 0.41 kg / L) transported by pump 3 were thoroughly mixed in mixer 2 at a flow rate ratio of 1.1:1 and a retention time of 12 min, and then sent to reactor 2, where the addition reaction was carried out at 60°C. The reaction liquid flowing out of reactor 2 flows into and passes through a connected pipeline into a buffer tank, is transported to mixer 3 by pump 4, and is mixed with raw material 5 (dimethyl phosphite) transported by pump 5 at a flow rate ratio of 4:1 with a retention time of 8 minutes. The mixture is then sent directly to reactor 3 via a connected pipeline, where an esterification reaction is carried out at 60°C. The esterification reaction liquid flowing out of reactor 3 is sent to reactor 4, where an esterification reaction is continued at 75°C, and the raw materials are completely converted. The reaction liquid flowing out of reactor 4 flows through backpressure valve 1. The function of backpressure valve 1 is to adjust the reaction pressure in reactors 3 and 4. The reaction liquid flowing out of backpressure valve 1 entered mixer 4 and was thoroughly mixed with raw material 6 (35% hydrochloric acid) transported by pump 6 at a flow rate ratio of 2:1 with a retention time of 2.5 min. The mixture was then sent to reactor 5 for neutralization. The reaction liquid was then sent directly to reactor 6 via a connected pipeline, where it was subjected to a hydrolysis reaction at 150°C for a retention time of 2 min while the temperature of the reaction liquid was increased. The reaction liquid flowing out of reactor 6 passed through backpressure valve 2, which serves to adjust the reaction pressure in reactors 5 and 6. To improve the removal efficiency of low-boiling point solvents and compounds after entering reactor 1 in the continuous reactor, the liquid flowing out of reactor 6 was sent to reactor 1 from the bottom (temperature: 110°C, retention time: 35 min). The low-boiling point solvents and compounds were rapidly evaporated. The volatile gas entered a condensation collector connected to the vessel 1 through a pipe, and the remaining reaction liquid flowed upward from the bottom of the vessel 1 to the upper outlet, and then through a connecting pipe to the bottom of the vessel 2 (temperature 130°C, retention time 40 min), where the produced methyl chloride and some of the solvent water were continuously removed.The remaining reaction liquid flowed upward from the bottom of Tank 2 to the upper outlet, then passed through a connecting pipe to the bottom of Tank 3 (temperature 140°C, retention time 50 min), where it was subsequently dealcoholized by hydrolysis for complete conversion. The reaction liquid was then sent to a continuous crystallizer (temperature 65°C, retention time 15 min), where it was precipitated by lowering the temperature to obtain the product glyphosate. The purity of the product was greater than 96%, and the glyphosate yield, calculated as glycine, was 83%.

[0021] Example 2 The prepared raw material 1 (paraformaldehyde 0.32 kg / L) and raw material 2 (triethylamine) were transported to mixer 1 (micromixer 1) by pump 1 and pump 2, respectively, at a flow rate ratio of 2.5:1 and thoroughly mixed (retention time 6 min). After mixing, they were sent directly to reactor 1 via a connected pipe, where the depolymerization reaction of paraformaldehyde was carried out at 50°C. The reaction liquid flowing out of reactor 1 and raw material 3 (glycine 0.21 kg / L) transported by pump 3 were thoroughly mixed in mixer 2 at a flow rate ratio of 1:1 and a retention time of 10 min, and then sent to reactor 2, where the addition reaction was carried out at 65°C. The reaction liquid flowing out of reactor 2 flowed into and passed through a connected pipeline into a buffer tank, was transported to mixer 3 by pump 4, and was mixed with raw material 5 (dimethyl phosphite) transported by pump 5 at a flow rate ratio of 3.5:1 with a retention time of 4 minutes. The mixture was then sent directly to reactor 3 via a connected pipeline, where an esterification reaction was carried out at 70°C. The esterification reaction liquid flowing out of reactor 3 was sent to reactor 4, where an esterification reaction was continued at 75°C, and the raw materials were completely converted. The reaction liquid flowing out of reactor 4 passed through backpressure valve 1. The function of backpressure valve 1 was to adjust the reaction pressure in reactors 3 and 4. The reaction liquid flowing out of backpressure valve 1 entered mixer 4, where it was thoroughly mixed with raw material 6 (30.5% hydrochloric acid) transported by pump 6 at a flow rate ratio of 2:1.5 and a retention time of 2 min. The mixture was then sent to reactor 5 for neutralization. The reaction liquid was then sent directly to reactor 6 via a connected pipeline, where it was subjected to a hydrolysis reaction at 140°C for a retention time of 1 min while the temperature of the reaction liquid was increased. The reaction liquid flowing out of reactor 6 passed through backpressure valve 2, which serves to adjust the reaction pressure in reactors 5 and 6. To improve the removal efficiency of low-boiling point solvents and compounds after entering reactor 1 in the continuous reactor, the liquid flowing out of reactor 6 was sent to reactor 1 from the bottom (temperature: 100°C, retention time: 30 min). The low-boiling point solvents and compounds were rapidly evaporated. The volatile gases entered a condensation collector connected to the vessel 1 through a pipe, and the remaining reaction liquid flowed upward from the bottom of the vessel 1 to the upper outlet, and then through a connecting pipe to the bottom of the vessel 2 (temperature 125°C, retention time 45 min), where the produced methyl chloride and some of the solvent water were continuously removed.The remaining reaction liquid flowed upward from the bottom of Tank 2 to the upper outlet, then passed through a connecting pipe to the bottom of Tank 3 (temperature 145°C, retention time 45 min), where it was subsequently dealcoholized by hydrolysis for complete conversion. The reaction liquid was then sent to a continuous crystallizer (temperature 70°C, retention time 12 min), where it was precipitated by lowering the temperature to obtain the product glyphosate. The purity of the product was greater than 98%, and the glyphosate yield, calculated as glycine, was 84%.

[0022] Example 3 The prepared raw material 1 (paraformaldehyde 0.84 kg / L) and raw material 2 (triethylamine) were transported to mixer 1 (micromixer 1) by pump 1 and pump 2, respectively, at a flow rate ratio of 1.5:1 and thoroughly mixed (retention time 7 min). After mixing, they were sent directly to reactor 1 via a connected pipeline, where the depolymerization reaction of paraformaldehyde was carried out at 55°C. The reaction liquid flowing out of reactor 1 and raw material 3 (glycine 0.45 kg / L) transported by pump 3 were thoroughly mixed in mixer 2 at a flow rate ratio of 1.5:1 and a retention time of 8 min, and then sent to reactor 2, where the addition reaction was carried out at 60°C. The reaction liquid flowing out of reactor 2 flowed into and passed through a connected pipeline into a buffer tank, was transported to mixer 3 by pump 4, and was mixed with raw material 5 (dimethyl phosphite) transported by pump 5 at a flow rate ratio of 3.0:1 with a retention time of 8 minutes. The mixture was then sent directly to reactor 3 via a connected pipeline, where an esterification reaction was carried out at 62°C. The esterification reaction liquid flowing out of reactor 3 was sent to reactor 4, where the esterification reaction continued at 80°C, resulting in complete conversion of the reaction raw materials. The reaction liquid flowing out of reactor 4 flowed through backpressure valve 1. The function of backpressure valve 1 was to adjust the reaction pressure in reactors 3 and 4. The reaction liquid flowing out of backpressure valve 1 entered mixer 4 and was thoroughly mixed with raw material 6 (31.5% hydrochloric acid) transported by pump 6 at a flow rate ratio of 2:1.3 with a retention time of 1.5 min. The mixture was then sent to reactor 5 for neutralization. The reaction liquid was then sent directly to reactor 6 via a connected pipeline, where it was subjected to a hydrolysis reaction at 120°C for a retention time of 0.8 min while the temperature of the reaction liquid was increased. The reaction liquid flowing out of reactor 6 passed through backpressure valve 2, which serves to adjust the reaction pressure in reactors 5 and 6. To improve the removal efficiency of low-boiling point solvents and compounds after entering reactor 1 in the continuous reactor, the liquid flowing out of reactor 6 was sent to reactor 1 from the bottom (temperature: 120°C, retention time: 25 min). The low-boiling point solvents and compounds were rapidly evaporated. The volatile gas entered a condensation collector connected to the vessel 1 through a pipe, and the remaining reaction liquid flowed upward from the bottom of the vessel 1 to the upper outlet, and then through a connecting pipe to the bottom of the vessel 2 (temperature 135°C, retention time 40 min), where the produced methyl chloride and some of the solvent water were continuously removed.The remaining reaction liquid flowed upward from the bottom of Tank 2 to the upper outlet, then passed through a connecting pipe to the bottom of Tank 3 (temperature 150°C, retention time 42 min), where it was subsequently dealcoholized by hydrolysis for complete conversion. The reaction liquid was then sent to a continuous crystallizer (temperature 68°C, retention time 15 min), where it was precipitated by lowering the temperature to obtain the product glyphosate. The purity of the product was greater than 97%, and the glyphosate yield was 83.5% in terms of glycine.

[0023] Any changes and modifications to the embodiments described in this specification based on the concept of the present invention, or equivalent structure or equivalent process transformations made according to the contents of this specification and drawings, or direct or indirect application of the above technical means to other related technologies, are all included in the protection scope of the present invention.

Claims

1. A completely continuous synthesis apparatus for glyphosate, Seven feed pumps, four micromixers, six microchannel reactors, three stirring vessels, one buffer tank, two back pressure valves, and one continuous crystallizer are connected in sequence according to the synthesis pathway of glyphosate to form a complete continuous chemical synthesis device that matches the synthesis pathway of glyphosate; The prepared first material and second material are respectively transported to the first micro-mixer by the first pump and the second pump, and after being thoroughly mixed, directly enter the first micro-channel reactor through the connecting pipe to carry out the depolymerization of paraformaldehyde; the reaction liquid flowing out of the first microchannel reactor and the third material transported by the third pump are thoroughly mixed in the second micromixer, and then enter the second microchannel reactor as is, where an addition reaction occurs; The reaction liquid flowing out of the second microchannel reactor is fed to the buffer tank as a fourth material through a connecting pipe, and the fourth material is transported to the third micromixer by the fourth pump, and mixed with the fifth material transported by the fifth pump, and then directly fed to the third microchannel reactor through a connecting pipe for esterification reaction. In order to promote complete conversion of the reaction raw materials, the temperature in the fourth microchannel reactor is set slightly higher than that in the third microchannel reactor; The reaction liquid flowing out of the fourth microchannel reactor flows through the first back-pressure valve, and the function of the first back-pressure valve is to adjust the reaction pressure in the third and fourth microchannel reactors. The reaction liquid flowing out of the first back-pressure valve enters the fourth micro-mixer and is thoroughly mixed with the sixth material transported by the sixth pump, and then enters the fifth microchannel reactor to carry out a neutralization reaction. The reaction liquid flowing out of the fifth microchannel reactor directly enters the sixth microchannel reactor through a connecting pipe to carry out a hydrolysis reaction, and simultaneously raises the temperature of the reaction liquid; The liquid flowing out of the sixth microchannel reactor enters the first stirred tank from the bottom, where the low-boiling point solvent and compounds rapidly volatilize, and the volatile gas enters a condensation collector connected to the first stirred tank through a pipeline. The remaining reaction liquid flows up from the bottom of the first stirred tank to the top outlet, and then enters the lower part of the second stirred tank through a connecting pipeline. The produced methyl chloride and some of the solvent water are continuously removed. The remaining reaction liquid flows up from the bottom of the second stirred tank to the top outlet, and then enters the lower part of the third stirred tank through a connecting pipeline. The reaction liquid then undergoes hydrolysis to undergo dealcoholization for complete conversion. The reaction liquid then enters a continuous crystallizer, where the product glyphosate is precipitated as the temperature drops.

2. 2. The apparatus for completely continuously synthesizing glyphosate according to claim 1, wherein the first pump and the third pump are peristaltic pumps for transporting a slurry, and the second, fourth, fifth, sixth and seventh pumps are plunger pumps for transporting a solution.

3. The first to fourth micromixers are micromixers each consisting of four diamond-shaped pipe mixing elements connected in series, and the cross section of the diamond-shaped pipe flow path has a size of 100 μm. ２ -20mm ２ The apparatus for completely continuous synthesis of glyphosate according to claim 1, characterized in that it is circular or square, its length is 1-100cm, and its application flow rate is 1-3000mL / min.

4. The apparatus for completely continuous synthesis of glyphosate according to claim 1, characterized in that the second microchannel reactor is a rotary dynamic reactor, specifically a cylindrical cavity, the wall of the cylindrical cavity is a heat exchange fluid intervening layer for heat flow to pass through, a central shaft is provided within the cylindrical cavity, and a plurality of stirring blades are connected to the central shaft to enhance mass transfer and heat transfer, the central shaft is driven by a motor, and the rotation speed is 50-500 rpm / min, the cavity is cylindrical, has a diameter of 3-60 cm, a length of 20-500 cm, and an applied flow rate is 10-50,000 mL / min.

5. The apparatus for completely continuous synthesis of glyphosate according to claim 1, wherein the first, third, fourth, fifth, and sixth microchannel reactors are tubular micromixers incorporating a plurality of square mixing elements arranged sequentially along the axial direction, each having a channel size of 2-500 mm, a length of 1-10,000 m, and an applied flow rate of 10-50,000 mL / min.

6. The apparatus for completely continuous synthesis of glyphosate according to claim 1, characterized in that the size of the connecting pipe of the first back pressure valve and the second back pressure valve is 1.6mm-20mm, and the pressure condition range is 0.1-2.0MPa.

7. The first stirring kettle, the second stirring kettle, and the third stirring kettle are stirring kettle having a stirring blade, a low boiling point distillate outlet, a heat exchange jacket fluid inlet / outlet, and a material inlet / outlet, and the three stirring kettle are connected in series by pipelines to realize the circulation of heat exchange fluid and materials, and the inner diameter of the stirring kettle body is 5-1000 cm, and the height is 5-1000 cm. The fully continuous glyphosate synthesis apparatus according to claim 1.

8. The continuous crystallizer is a tubular reactor having a mixing structure and a heat exchange jacket, the tubular reactor has an S-shaped pipe, the pipe wall is a heat exchange layer for heat flow, and a plurality of spherical baffles are uniformly distributed inside the pipe, the tubular reactor has an inner diameter of 2-20 cm, a length of 1-1000 m, and an applicable flow rate of 10-5000 mL / min.

9. 2. The apparatus for completely continuously synthesizing glyphosate according to claim 1, characterized in that: the first material is a solution or slurry of paraformaldehyde dissolved or dispersed in a solvent; the second material is a solvent-free alkali or a solution of alkali dissolved in a solvent; the third material is a solution or slurry of glycine dissolved or dispersed in a solvent; the fourth material is an intermediate solution produced in the second microchannel reactor; the fifth material is solvent-free dimethyl phosphite or a solution of dimethyl phosphite dissolved in a solvent; and the sixth material is solvent-free acid or a solution of acid dissolved in a solvent.

10. In the operation process of the glyphosate completely continuous synthesis apparatus, The prepared first material and second material are respectively transported to the first micro-mixer by the first pump and the second pump, and after being thoroughly mixed, directly enter the first micro-channel reactor through the connecting pipe to carry out the depolymerization of paraformaldehyde; the reaction liquid flowing out of the first microchannel reactor and the third material transported by the third pump are thoroughly mixed in the second micromixer, and then enter the second microchannel reactor as is, where an addition reaction occurs; The reaction liquid flowing out of the second microchannel reactor is fed to the buffer tank as a fourth material through a connecting pipe, and the fourth material is transported to the third micromixer by the fourth pump, and mixed with the fifth material transported by the fifth pump, and then directly fed to the third microchannel reactor through a connecting pipe for esterification reaction. In order to promote complete conversion of the reaction raw materials, the temperature in the fourth microchannel reactor is set slightly higher than that in the third microchannel reactor; The reaction liquid flowing out of the fourth microchannel reactor flows through the first back-pressure valve, and the function of the first back-pressure valve is to adjust the reaction pressure in the third and fourth microchannel reactors. The reaction liquid flowing out of the first back-pressure valve enters the fourth micro-mixer and is thoroughly mixed with the sixth material transported by the sixth pump, and then enters the fifth microchannel reactor to carry out a neutralization reaction. The reaction liquid flowing out of the fifth microchannel reactor directly enters the sixth microchannel reactor through a connecting pipe to carry out a hydrolysis reaction, and simultaneously raises the temperature of the reaction liquid; The liquid flowing out of the sixth microchannel reactor enters the first stirred tank from the bottom, where the low boiling point solvent and compounds rapidly volatilize. The volatile gas enters the condensation collector connected to the first stirred tank. The remaining reaction liquid flows up from the bottom of the first stirred tank to the top outlet, and then enters the lower part of the second stirred tank through the connecting pipe. The produced methyl chloride and some of the solvent water are continuously removed. The remaining reaction liquid flows up from the bottom of the second stirred tank to the top outlet, and then enters the lower part of the third stirred tank through the connecting pipe. The alcohol is then dealcoholized by hydrolysis to achieve complete conversion. The reaction liquid then enters the continuous crystallizer, where the temperature is lowered to precipitate the product glyphosate. The first microchannel reactor has a temperature of 30-60°C and a reaction time of 1-9 min, the second microchannel reactor has a temperature of 45-80°C and a reaction time of 6-12 min, the third microchannel reactor has a temperature of 50-80°C and a reaction time of 1-8 min, the fourth microchannel reactor has a temperature of 60-90°C and a reaction time of 5-15 min, the fifth microchannel reactor has a temperature of 0-30°C and a reaction time of 0.5-3 min, and the sixth microchannel reactor has a temperature of 50-80°C and a reaction time of 1-8 min. The apparatus for completely continuously synthesizing glyphosate according to any one of claims 1 to 9, characterized in that the microchannel reactor has a temperature of 90-190°C and a reaction time of 0.5-3 min, the first stirred tank has a temperature of 80-150°C and a reaction time of 5-40 min, the second stirred tank has a temperature of 80-150°C and a reaction time of 5-40 min, the third tank has a temperature of 90-160°C and a reaction time of 5-60 min, and the continuous crystallizer has a temperature of 0-80°C and a residence time of 1-30 min.

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