A continuous hydrolysis and acidolysis process for de-alcoholization of glyphosate

Abstract

The invention provides a continuous hydrolysis and acid de-alcoholization process of glyphosate. A glyphosate mixed acid liquid storage tank is connected to an acid de-alcoholization reactor. The acid de-alcoholization reactor is provided with a first reaction functional section, a second reaction functional section, a third reaction functional section, and a fourth reaction functional section from top to bottom. The first reaction functional section is a packing section. Other adjacent reaction functional sections are separated by an overflow plate. The overflow plate can realize the movement of liquid phase from top to bottom. The upper layer of the liquid surface of the fourth reaction functional section is connected to the upper end of the third reaction functional section through a gas phase pipeline; the upper layer of the liquid surface of the third reaction functional section is connected to the upper end of the second reaction functional section through a gas phase pipeline. In each functional section, the gas phase of each level flows from bottom to top to the upper section by pressure difference, and the gas-liquid contact at a certain height is maintained in the upper section for mass transfer and heat transfer. The gas-liquid mass transfer and heat transfer are enhanced by steam stripping and aeration, and the gas stripping effect is played to quickly remove materials such as formaldehyde, methylal, and methyl chloride in the material.

Description

Technical Field

[0001] The invention relates to the technical field of glyphosate production, in particular to a continuous reaction system for a glyphosate raw material drug in a continuous acid-dealcoholization process of glyphosate. Background Art

[0002] Glyphosate is a highly efficient, low-toxic, broad-spectrum, lethal, non-selective herbicide with excellent biological properties. It is the herbicide variety with the largest production volume in the world. At present, there are two mainstream production processes for glyphosate in China: the alkyl ester method (glycine method) and the iminodiacetic acid method (IDA method). The production process abroad is mainly the iminodiacetic acid method of Monsanto Company in the United States. 70% of my country's glyphosate production capacity is produced by the alkyl ester method with glycine and dimethyl phosphite as the main raw materials. This method uses methanol as the reaction solvent. In the presence of the catalyst triethylamine, glycine, polyformaldehyde, and dimethyl phosphite react to obtain a synthetic liquid (glyphosate synthetic liquid). A certain proportion of the synthetic liquid is mixed with acid to obtain a glyphosate mixed acid liquid (also known as a mixed liquid, acidolysis liquid, and hydrolysis liquid in the industry). Steam is used to heat the mixture to the reaction endpoint temperature. As the temperature rises, hydrolysis and acidolysis reactions occur to generate glyphosate and by-products methylal and chloromethane. Methylal, methanol, chloromethane and other steam are evaporated from the reactor. The remaining liquid phase after the acid hydrolysis reaction is glyphosate slurry, which is crystallized, separated, washed and dried to obtain glyphosate technical that meets national standards.

[0003] The gaseous tail gas of the acidolysis reaction (i.e., the light component extracted by the fan) is mainly composed of water, methylal, methanol, hydrogen chloride and methyl chloride mixture. The tail gas is sent to the gaseous tail gas recovery device for recovery and treatment. The recovery process is referred to as solvent recovery and methyl chloride recovery in the glyphosate industry: the distilled mixed gas is condensed in multiple stages, the condensate (diluted methanol) is sent to the solvent recovery device, and the non-condensable gas is treated by the methyl chloride recovery device; or the high-temperature tail gas is condensed or absorbed to recover dilute hydrochloric acid; or the distilled mixed gas is first neutralized in a neutralization tower, and the neutralized gas is used to recover methanol and methylal, and the non-condensable gas is treated by the methyl chloride recovery device. Methanol is reused as a solvent in the glyphosate synthesis process, and methylal and methyl chloride are sold as by-products.

[0004] The production of glyphosate by the glycine method has a history of more than 30 years. The processes of solvent recovery, triethylamine recovery, and methyl chloride recovery have been continuously realized in the industry. Due to the limitations of factors such as the characteristics of the glyphosate acidolysis reaction, the acidolysis dealcoholization process is still an intermittent stirred tank method.

[0005] The intermittent hydrolysis process of glyphosate has the following problems: 1. Low production efficiency, high comprehensive energy consumption, and high labor intensity of workers. 2. The capacity of a single set of equipment is small, the number of reactors per unit production capacity is large, and there are many instrument control points. There is a lack of effective continuity before and after, and there are problems such as unstable product quality caused by human factors in operation, which also restricts the expansion of production equipment and the improvement of intrinsic safety. Continuous production of glyphosate can completely overcome these shortcomings through automated control. Therefore, the development of a continuous acid-dehydrolysis device for glyphosate is one of the main research directions of glyphosate production enterprises.

[0006] Patent CN 111205319 A discloses a continuous synthesis method and system of glyphosate by glycine method, wherein the mixed acid liquid obtained by acidification of the synthetic liquid is subjected to primary hydrolysis reaction and secondary hydrolysis reaction, and the slurry after the secondary hydrolysis reaction is crystallized to obtain glyphosate. The primary hydrolysis reaction device comprises a primary hydrolysis reaction tower and a primary hydrolysis reaction kettle; the secondary hydrolysis reaction device comprises a secondary hydrolysis reaction kettle, and the gas outlet of the secondary hydrolysis reaction device is connected to a hydrolysis tail gas condenser. The tail gas of the primary hydrolysis reaction device and the condensate and tail gas of the primary hydrolysis reaction device are sent to a methanol recovery device for treatment. The hydrolysis reaction device of the method is divided into multiple stages, the device is complex, the process is long, the acidolysis reaction time is long, and the yield is not high. Moreover, the method still relies on an enamel kettle as a reactor. Summary of the invention

[0007] In view of the above technical problems, the present invention provides a continuous reaction system for glyphosate raw materials, wherein a glyphosate acidolysis liquid storage tank is connected to an acidolysis deethanolation reactor, and the acidolysis deethanolation reactor is provided with a first reaction functional section, a second reaction functional section, a third reaction functional section, and a fourth reaction functional section from top to bottom, wherein the first reaction functional section is a packing section, and other adjacent reaction functional sections are separated by an overflow plate, and the overflow plate can realize the liquid phase flowing from top to bottom.

[0008] A continuous hydrolysis and acid de-alcoholization process for glyphosate, wherein the material flow in the continuous hydrolysis and acid de-alcoholization process comprises the following steps:

[0009] After the glyphosate mixed acid liquid enters the first reaction functional section of the acid de-alcoholization reactor, the liquid phase enters the second reaction functional section through the filler of the first reaction functional section;

[0010] After the reaction liquid reacts in the second reaction functional section, the liquid phase flows from the overflow plate or the liquid phase pipeline to the Nth reaction functional section;

[0011] After the reaction liquid reacts in the Nth reaction functional section, the liquid phase flows from the overflow plate or the liquid phase pipeline to the N+1th reaction functional section, and reacts in the N+1th reaction functional section to obtain glyphosate slurry, wherein N is 2-10.

[0012] The N is 3, then, in the material flow step in the continuous hydrolysis acid deethanolation process, after the glyphosate mixed acid liquid enters the first reaction functional section of the acid deethanolation reactor; the liquid phase enters the second reaction functional section through the filler of the first reaction functional section;

[0013] After the reaction liquid reacts in the second reaction functional section, the liquid phase flows from the overflow plate or the liquid phase pipeline to the third reaction functional section;

[0014] After the reaction liquid reacts in the third reaction functional section, the liquid phase flows from the overflow plate or the liquid phase pipeline to the fourth reaction functional section;

[0015] The reaction is carried out in the fourth reaction functional section to obtain glyphosate slurry.

[0016] The specific gravity of glyphosate mixed acid solution is 0.92-1.12.

[0017] The flow rate of the glyphosate mixed acid solution entering the first reaction functional section of the acid de-alcoholization reactor is a, and the flow rate of a ranges from 1t / h to 150t / h;

[0018] After the reaction liquid reacts in the second reaction functional section, the liquid phase in the second reaction functional section enters the third reaction functional section through the liquid phase pipeline at a flow rate of c for reaction, and the flow rate of c is 50-90% of a;

[0019] After the reaction liquid reacts in the third reaction functional section, the liquid phase in the third reaction functional section enters the fourth reaction functional section through the liquid phase pipeline at a flow rate d for reaction, and the flow rate d is 30-70% of a.

[0020] The liquid phase in the second reaction functional section enters the third reaction functional section from the overflow plate and the upper 3 / 5-1 / 8 of the second reaction functional section for reaction; wherein, the flow rate of the second reaction functional section entering the third reaction functional section through the overflow plate is e, and the flow rate of e is 1-100% of c; the flow rate of the upper 3 / 5-1 / 8 of the second reaction functional section entering the third reaction functional section is f, and the flow rate of f is 1-100% of c; and e+f=c, e:f≥0.5.

[0021] The liquid phase in the third reaction functional section enters the fourth reaction functional section from the overflow plate and the upper 3 / 5-1 / 8 of the third reaction functional section for reaction; wherein, the flow rate of the third reaction functional section entering the fourth reaction functional section from the overflow plate is g, and the flow rate of g is 1-100% of d, and the flow rate of the upper 3 / 5-1 / 8 of the third reaction functional section entering the fourth reaction functional section is h, and the flow rate of h is 1-100% of d, and g+h=d, g:h≥0.5.

[0022] The temperature in the second reaction functional section is controlled at 60-90°C and the pressure is -20kpa-30kpa; the temperature in the third reaction functional section is controlled at 88-112°C and the pressure is -2-40kPa; the temperature in the fourth reaction functional section is controlled at 105-140°C and the pressure is -2-100kPa.

[0023] 10-100% volume fraction of the liquid phase in the second reaction functional section is injected into the middle of the second reaction functional section again by a circulation pump to achieve circulation. 10-100% volume fraction of the liquid phase in the third reaction functional section is injected into the heater by a circulation pump to heat and then injected into the middle of the third reaction functional section again to achieve circulation. At the same time, the reaction temperature of the third reaction functional section is controlled to be 88-112°C.

[0024] 10-100% mass fraction of liquid phase in the fourth reaction functional section is pumped into heater 2 through a circulation pump for heating, and then injected into the fourth reaction functional section again in a jet manner to achieve circulation. At the same time, the reaction temperature of the fourth reaction functional section is controlled to 105-140°C. The other side of the circulation pump is connected to the discharge pipeline with a flow rate of q.

[0025] Part of the gas phase of the fourth reaction functional section enters the middle of the third reaction functional section in the form of gas injection, and part enters the gas recovery device; part of the gas phase of the third reaction functional section enters the second reaction functional section, and part enters the gas recovery device.

[0026] The fourth reaction functional section generates a gas phase flow rate of i, and the flow rate of i is 15-24% of a, wherein: the flow rate j enters the middle part of the third reaction functional section in the form of gas injection, and the flow rate of j is 0-100% of i; the flow rate k is connected to the gas recovery device by a gas phase pipeline, and the flow rate of k is 0-100% of i, and j+k=i.

[0027] The third reaction functional section generates a gas phase flow rate of m, and the flow rate of m is a, wherein: the flow rate n enters the middle part of the second reaction functional section in the form of gas injection, and the flow rate of n is 0-100% of m; the flow rate p is connected to the gas recovery device by a gas phase pipeline, and the flow rate of p is 0-100% of m, and n+p=m.

[0028] The continuous synthesis method of glyphosate provided by the present invention is achieved by the following specific technical scheme:

[0029] The synthetic liquid is fully mixed with a certain amount of acid in advance to obtain a mixed acid solution for standby use. The mixing process can be carried out in a stirred reactor (intermittent mixing) or continuously mixed by a pipeline mixer.

[0030] The mixed acid solution is continuously pumped into the reactor from the top feed port and enters the tower through the liquid distributor.

[0031] Preferably, the acid is a methanol solution of hydrochloric acid or hydrogen chloride.

[0032] Preferably, the stirred reactor (mixing reactor) is replaced by a static mixer, and the continuous and stable synthetic liquid feed and the hydrochloric acid added in proportion according to the process requirements enter the static mixer together for continuous mixing.

[0033] Preferably, the mixed acid liquid is preheated using a heat source such as steam condensed water produced as a byproduct of the heat exchanger in the third and fourth reaction functional sections of this scheme before entering the tower.

[0034] In each functional section, the liquid phase with the light components removed flows from top to bottom through the overflow plate to the next section by gravity. The material vapor from the second-stage reaction functional section at the bottom of the tower contacts the mixed acid liquid entering from the top of the tower in countercurrent in the first-stage reaction functional section for mass transfer, heat exchange, reaction and degassing. After preheating and preliminary dealcoholization in the first-stage reaction functional section, the liquid phase enters the second-stage reaction functional section. The temperature of this section is maintained by the heat energy brought in by the higher-temperature non-condensable gas and saturated steam generated in the next-stage reaction functional section, and is balanced with the heat energy consumed by the vaporization of methanol and water in this section. The volatile methylal and methanol components are vaporized and leave the reactor with the rising non-condensable gas. The reaction liquid then enters the third and fourth-stage reaction functional sections through overflow and underflow in turn for temperature reaction. The temperature of the third-stage reaction functional section is jointly maintained and controlled by the higher-temperature non-condensable gas and saturated steam generated in the fourth-stage reaction functional section and the heater on the external circulation pipeline; the temperature of the fourth-stage reaction functional section is maintained and controlled by the heater on the external circulation pipeline;

[0035] Alternatively, part of the liquid phase can flow to the next section through the upper liquid phase pipeline as an auxiliary liquid flow, and the flow rate can be adjusted by an automatic control valve to balance the liquid level and pressure of each reaction functional area. As a special case, when the valve opening of the upper liquid phase pipeline is 0% or the reactor is not provided with an upper liquid phase passage at this stage, all the liquid flows through the overflow plate into the next reaction functional section.

[0036] When sieve plates are used to divide functional zones, part of the liquid flows through the sieve holes of the tower plates to the next section.

[0037] In each functional section, the gas phase of each level flows from bottom to top to the upper section by pressure difference, and maintains a certain height of gas-liquid contact in the upper section for mass transfer and heat transfer. The gas-liquid mass transfer and heat transfer are enhanced through stripping and aeration, and the gas stripping effect is played to quickly remove formaldehyde, methylal, methyl chloride and other materials in the material.

[0038] The light components in the reaction liquid (methanol, water, hydrogen chloride, and methylal and chloromethane generated during the acidolysis reaction) form a gas phase and are discharged from the upper gas phase pipes of the first reaction functional section, the second reaction functional section, the third reaction functional section, and the fourth reaction functional section. Among them, the upper part of the first reaction functional section is the top of the tower. The gas phase tail gas generated in the second reaction functional section is discharged from the top of the tower after mass transfer and heat transfer in the first reaction functional section.

[0039] Alternatively, part of the gas phase can be directly sent to the gas phase main pipe through the gas phase pipeline as an auxiliary gas flow, and the flow rate can be adjusted by an automatic control valve to balance the pressure of each reaction functional zone. As a special case, when the valve opening of the auxiliary gas flow pipeline of the current reaction section is 0% or the reactor is not provided with an auxiliary gas flow passage, the gas flow all flows from bottom to top to the next reaction functional section by the pressure difference.

[0040] The gaseous tail gas of the above acidolysis reaction (i.e., the light component extracted by the fan) is mainly composed of water, methylal, methanol, hydrogen chloride and methyl chloride mixture, which is sent to the solvent recovery and methyl chloride recovery steps to recover methanol, methylal and methyl chloride.

[0041] In the second, third and fourth stage reaction functional sections, circulation pumps are respectively provided to force the reaction liquid to circulate, and microscopic mixing is achieved through nozzles and guide tube structures.

[0042] In the third and fourth reaction functional sections, an external heater is installed on the circulation pipeline, and the reaction liquid is heated by the heater before the circulation reflux to maintain the reaction liquid at the specified temperature. In the third reaction functional section, the reaction liquid is fully circulated. In the fourth reaction functional section, part of the material is refluxed and part of the material is extracted.

[0043] The reaction liquid is treated in a continuous acid dealcoholization tower to realize an acid dealcoholization reaction in a stirred tank process to generate glyphosate and obtain a glyphosate feed liquid.

[0044] In the process of acid dealcoholization, optionally, a certain amount of acid is added to any one or several of the second, third, and fourth reaction functional sections in the reactor to improve the hydrolysis and acidolysis efficiency. Optionally, a certain amount of process water is added to any one or several of the second, third, and fourth reaction functional sections in the reactor to adjust the viscosity and solid content of the reaction system. At the same time, the vaporization of water will produce a gas lift effect, further improving the dealcoholization and deacidification efficiency.

[0045] Functionally, the reactor described in this scheme realizes the composite functions of plug flow and full mixed flow reactor in one reactor. By designing different functional sections and optimizing the acidolysis and hydrolysis chemical reaction process, in each functional section, the gas phases of each level flow from bottom to top to the upper section by pressure difference, and maintain a certain height of gas-liquid countercurrent contact in the upper section for mass transfer and heat transfer, and the gas-liquid mass transfer and heat transfer are enhanced by stripping and aeration. In the last three reaction functional sections, macroscopic mixing is achieved by the large circulation of the pump and the microscopic mixing structure to produce a strong surface renewal effect, and microscopic mixing is achieved by the nozzle and guide tube structure to promote the mixing effect. Therefore, the "re-mixing" problem faced in the process of continuous intermittent stirring tank process improvement is solved, and the problems of incomplete reaction of the original continuous technology (appearance of raw materials) are solved. Therefore, the acidolysis and hydrolysis chemical reaction process is fully and thoroughly, the continuous operation is stable and reliable, and all acidolysis reactions are completed in one reactor, and no enamel kettle is required for further auxiliary reaction; compared with the original intermittent stirring process, the yield is high, the heat is stepped, and the steam energy consumption is low.

[0046] In the case of the sieve plate, the upper layer of the liquid surface of the fourth reaction functional section is connected to the gas recovery device via a gas phase pipeline; the upper layer of the liquid surface of the third reaction functional section is connected to the gas recovery device via a gas phase pipeline, and the first reaction functional section is connected to the gas recovery device via a gas phase pipeline.

[0047] In each functional section, the liquid phase after the light components are removed flows from top to bottom through the sieve plate by gravity to the next section. The material vapor from the second-stage reaction functional section at the bottom of the tower contacts the mixed acid liquid entering from the top of the tower in the first-stage reaction functional section in countercurrent to carry out mass transfer, heat exchange, reaction and degassing. After preheating and preliminary dealcoholization in the first-stage reaction functional section, the liquid phase enters the second-stage reaction functional section. The temperature of this section is maintained by the heat energy brought in by the higher temperature non-condensable gas and saturated steam generated in the next-stage reaction functional section, and is balanced with the heat energy consumed by the vaporization of methanol and water in this section. The volatile methylal and methanol components are vaporized and leave the reactor with the rising non-condensable gas. The reaction liquid then enters the third and fourth-stage reaction functional sections through overflow and underflow in turn to heat up and react. The temperature of the third-stage reaction functional section is jointly maintained and controlled by the higher temperature non-condensable gas and saturated steam generated in the fourth-stage reaction functional section and the heater on the external circulation pipeline; the temperature of the fourth-stage reaction functional section is maintained and controlled by the heater on the external circulation pipeline.

[0048] Alternatively, part of the liquid phase can flow to the next section through the upper liquid phase pipeline as an auxiliary liquid flow, and the flow rate can be adjusted by an automatic control valve to balance the liquid level and pressure of each reaction functional area. As a special case, when the valve opening of the upper liquid phase pipeline is 0% or the reactor is not provided with an upper liquid phase at this stage, all the liquid flows through the sieve plate into the next reaction functional section.

[0049] In each functional section, the gas phase of each level flows from bottom to top to the upper section by pressure difference, and maintains a certain height of gas-liquid contact in the upper section for mass transfer and heat transfer. The gas-liquid mass transfer and heat transfer are enhanced through stripping and aeration, and the gas stripping effect is played to quickly remove formaldehyde, methylal, methyl chloride and other materials in the material.

[0050] The light components in the reaction liquid (methanol, water, hydrogen chloride, and methylal and chloromethane generated during the acidolysis reaction) form a gas phase and are discharged from the upper gas phase pipes of the first reaction functional section, the second reaction functional section, the third reaction functional section, and the fourth reaction functional section. Among them, the upper part of the first reaction functional section is the top of the tower. The gas phase tail gas generated in the second reaction functional section is discharged from the top of the tower after mass transfer and heat transfer in the first reaction functional section.

[0051] Alternatively, part of the gas phase can be directly sent to the gas phase main pipe through the gas phase pipeline as an auxiliary gas flow, and the flow rate can be adjusted by an automatic control valve to balance the pressure of each reaction functional zone. As a special case, when the valve opening of the auxiliary gas flow pipeline of the current reaction section is 0% or the reactor is not provided with an auxiliary gas flow passage, the gas flow all flows from bottom to top to the next reaction functional section by the pressure difference.

[0052] The "re-mixing" problem faced in the process of continuous batch stirring tank process improvement has been solved, and the problems of incomplete reaction (raw materials) of the original continuous technology have been solved. Therefore, the acid hydrolysis and hydrolysis chemical reaction process is fully and thoroughly, the continuous operation is stable and reliable, and the entire acid hydrolysis reaction is completed in one reactor, and no enamel kettle is required for further auxiliary reaction; compared with the original batch stirring process, the yield is high, the heat is cascaded, and the steam energy consumption is low.

[0053] This device and process are continuous feeding, reaction and discharging. Therefore, based on the basic understanding of the chemical industry, it should be understood that the reaction tower feed flow, discharge flow, and the liquid phase flow and gas phase flow of each stage of the reaction functional section are always in a dynamic equilibrium state during continuous and stable operation. The embodiment of the present invention is the operation result obtained by continuous operation according to the given working conditions and parameter conditions. In the reaction tower, the pressure of each functional section is also in dynamic balance. When the positive pressure or negative pressure of the previous level is high, the pressure will balance to the adjacent previous and next levels. For example: when the negative pressure of the exhaust fan of the reaction tower tail gas recovery device tends to be large, the pressure of each level in the reaction tower will tend to be small as a whole, and even negative pressure will appear; when the negative pressure of the exhaust fan of the reaction tower tail gas recovery device tends to be small, the pressure of each level in the reaction tower tends to increase as a whole. Therefore, the pressure value intervals of the reaction functional sections at all levels overlap. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1The present invention is a process flow chart of the continuous synthesis of glyphosate raw materials in Example 1, wherein: 1. a glyphosate mixed acid liquid storage tank; 2. an acid dealcoholization reactor; 3. a first reaction functional section; 4. a second reaction functional section; 5. a third reaction functional section; 6. a fourth reaction functional section; 7. a heater one; 8. a heater two; 9. a gas recovery device; 10. a crystallizer; 11-1, 11-2, 11-3, 11-4, 11-5, and 11-6 are all circulation pumps; 12. an overflow plate; and 13. an injection device.

[0055] Figure 2 The process flow chart of the continuous synthesis of glyphosate API of Example 2 is shown in FIG. 1 , wherein: 1 '. glyphosate mixed acid liquid storage tank; 2 '. acid deethanolation reactor; 3 '. first reaction functional section; 4 '. second reaction functional section; 5 '. third reaction functional section; 6 '. fourth reaction functional section; 7 '. heater one; 8 '. heater two; 9 '. gas recovery device; 10 '. crystallizer; 11-1 ', 11-2 ', 11-3 ', 11-4 ', 11-5 ', 11-6 'are all circulation pumps; 12 '. overflow plate; 13 '. injection device.

[0056] Figure 3 This is the glyphosate API continuous reaction system of Example 3, wherein: 1". glyphosate mixed acid liquid storage tank, 2". acid dealcoholization reactor, 3". first reaction functional section, 4". second reaction functional section, 5". third reaction functional section, 6". fourth reaction functional section, 7". heater one, 8". heater two, 9". gas recovery device, 10". crystallizer, 11-1", 11-2", 11-3", 11-4", 11-5", 11-6" are all circulation pumps, 12". overflow plate, 13". injection device.

[0057] Figure 4 This is the glyphosate raw material continuous reaction system of Example 4, wherein 1"'. glyphosate mixed acid liquid storage tank, 2"'. acid deethanolation reactor, 3"'. first reaction functional section, 4"'. second reaction functional section, 5"'. third reaction functional section, 6"'. fourth reaction functional section, 7"'. heater one, 8"'. heater two, 9"'. gas recovery device, 10"'. crystallizer, 11-1"', 11-2"', 11-3"', 11-4"', 11-5"', 11-6"' are all circulating pumps, 12"'. overflow plate, 13"'. injection device.

[0058] Figure 5This is the continuous reaction system for glyphosate raw materials of Example 5, wherein a'. glyphosate mixed acid liquid storage tank, b'. acid deethanolation reactor, c'. first reaction functional section, d'. second reaction functional section, e'. third reaction functional section, f'. fourth reaction functional section, g'. heater one, h'. heater two, i'. gas recovery device, j'. crystallizer, k-1', k-2', k-3', k-4', k-5', k-6' are all circulation pumps, l'. overflow plate, m'. injection device.

[0059] Figure 6 This is the glyphosate raw material continuous reaction system of Example 6, wherein a". glyphosate mixed acid liquid storage tank, b". acid deethanolation reactor, c". first reaction functional section, d". second reaction functional section, e". third reaction functional section, f". fourth reaction functional section, g". heater one, h". heater two, i". gas recovery device, j". crystallizer, k-1". k-2". k-3". k-4". k-5". k-6". are all circulation pumps, l". overflow plate, m". injection device. DETAILED DESCRIPTION

[0060] Glyphosate mixed acid solution is a mixed acid solution obtained by acidifying a synthetic liquid during the continuous synthesis of glyphosate by the glycine method. For example, references CN1037396A and CN111205319A all obtained glyphosate mixed acid solution. This glyphosate mixed acid solution is a mixed acid solution that is difficult to handle and is well known to those skilled in the art.

[0061] Example 1

[0062] After the glyphosate mixed acid solution enters the first reaction functional section of the acido dealcoholization reactor at a speed of 2500kg / h, the liquid phase enters the second reaction functional section through the filler of the first reaction functional section, and enters the third and fourth reaction functional sections through the overflow plate. After the reaction liquid reacts in the second reaction section for about 1.5 hours, the liquid level rises to the downcomer and enters the third reaction functional section. According to the indication of the liquid level meter in the tower, the flow rate in the downcomer is calculated to be about 1800kg / h; after the reaction liquid reacts in the third reaction section for about 3 hours, it enters the fourth reaction functional section through the downcomer. According to the indication of the liquid level meter in the tower, the flow rate in the downcomer is calculated to be about 1200kg / h; after reacting for about 2 hours, process water is added to the third and fourth reaction functional sections at a flow rate of 130kg / h, and the flow rate of the second, third and fourth circulation pumps is controlled to be 8000kg / h for the second, third and fourth. The temperature of the third and fourth stages is controlled to be 108℃ and 130℃ by controlling the steam volume of the heater, and the temperature of the first and second stages is measured to be 55℃ and 84℃; the reaction liquid stays in the acid de-alcoholization reactor for 5-7 hours; the valve opening of the fourth reaction stage leading to the spraying device and the tail gas recovery device is controlled to be fully opened, and the gas phase flow rate of the fourth reaction stage connected to the third reaction stage through the spraying device is measured to be 248kg / h, and the gas phase flow rate of the tail gas recovery device is measured to be 252kg / h; the valve opening of the third reaction stage leading to the spraying device and the tail gas recovery device is controlled to be fully opened, and the gas phase flow rate of the third reaction stage connected to the second reaction stage through the spraying device is measured to be 617kg / h, and the gas phase flow rate of the tail gas recovery device is measured to be 378kg / h; the tail gas flow rate of the first stage of the tower top is 1001kg / h. The pressure at the top of the first functional stage of the reactor is -0.05kPa, and the pressures in the second, third and fourth functional stages are 2.1kpa, 4.3kpa and 4.8kpa. At 35 days, the flow rate of glyphosate slurry produced was 997 kg / h, the reaction conversion rate was 86.3%, and the content of glyphosate technical obtained after crystallization and washing was 96.4%.

[0063]

[0064] Example 2

[0065] After the glyphosate mixed acid solution enters the first reaction functional section of the acido dealcoholization reactor at a speed of 2500kg / h, the liquid phase enters the second reaction functional section through the filler of the first reaction functional section, and enters the third and fourth reaction functional sections through the overflow plate. After the reaction liquid reacts in the second reaction section for about 1.5 hours, the liquid level rises to the downcomer and enters the third reaction functional section. According to the indication of the liquid level meter in the tower, the flow rate in the downcomer is calculated to be about 1810kg / h; after the reaction liquid reacts in the third reaction section for about 3 hours, it enters the fourth reaction functional section through the downcomer. According to the indication of the liquid level meter in the tower, the flow rate in the downcomer is calculated to be about 1186kg / h; after reacting for about 2 hours, process water is added to the third and fourth reaction functional sections at a flow rate of 130kg / h, and the flow rate of the second, third and fourth stage circulation pumps is controlled to be 8000kg / h for the second, third and fourth stage reaction liquid The whole cycle; by controlling the steam amount of the heater, the temperature of the third and fourth sections is controlled to be 108°C and 130°C, and the temperature of the first and second sections is measured to be 52°C and 82°C; the reaction solution stays in the acid dealcoholization reactor for 5-7 hours; the valve opening of the fourth reaction section leading to the spray device and the tail gas recovery device is controlled to be 25% and fully open, and the gas flow rate of the fourth reaction section connected to the third reaction section through the spray device is measured to be 96kg / h, and the gas flow rate of the tail gas recovery device is measured to be 403kg / h; the valve opening of the third reaction section leading to the spray device and the tail gas recovery device is controlled to be 25% and fully open, and the gas flow rate of the third reaction section connected to the second reaction section through the spray device is measured to be 173kg / h, and the gas flow rate of the tail gas recovery device is measured to be 719kg / h; the tail gas pipe flow rate of the first section of the tower top is 498kg / h. The pressure at the top of the first functional section of the reactor was -0.05 kPa, and the pressures in the second, third and fourth functional sections were 2.0 kPa, 4.2 kPa and 4.8 kPa, respectively. At 72 hours, the flow rate of glyphosate slurry produced was 1012 kg / h, the reaction conversion rate was 85.6%, and the content of glyphosate technical obtained after crystallization and washing was 96.3%.

[0066] Example 3

[0067] After the glyphosate mixed acid solution enters the first reaction functional section of the acido dealcoholization reactor at a speed of 2500kg / h, the liquid phase enters the second reaction functional section through the filler of the first reaction functional section, and enters the third and fourth reaction functional sections through the overflow plate. After the reaction liquid reacts in the second reaction section for about 1.5 hours, the liquid level rises to the downcomer and enters the third reaction functional section. According to the indication of the liquid level gauge in the tower, the flow rate in the downcomer is calculated to be about 1795kg / h; after the reaction liquid reacts in the third reaction section for about 3 hours, it enters the fourth reaction functional section through the downcomer. According to the indication of the liquid level gauge in the tower, the flow rate in the downcomer is calculated to be about 1188kg / h; after reacting for about 2 hours, process water is added to the third and fourth reaction functional sections at a flow rate of 130kg / h, and the flow rate of the second, third and fourth stage circulation pumps is controlled to be 8000kg / h to carry out the second, third and fourth stage reaction liquid Full cycle; by controlling the steam amount of the heater, the temperature of the third and fourth sections is controlled to be 108°C and 130°C, and the temperature of the first and second sections is measured to be 55°C and 87°C; the reaction solution stays in the acid dealcoholization reactor for 5-7 hours; the valve opening of the fourth reaction section leading to the spray device and the tail gas recovery device is controlled to be fully opened and 25%, and the gas flow rate of the fourth reaction section connected to the third reaction section through the spray device is measured to be 395kg / h, and the gas flow rate of the tail gas recovery device is measured to be 103kg / h; the valve opening of the third reaction section leading to the spray device and the tail gas recovery device is controlled to be fully opened and 25%, and the gas flow rate of the third reaction section connected to the second reaction section through the spray device is measured to be 895kg / h, and the gas flow rate of the tail gas recovery device is measured to be 232kg / h; the tail gas flow rate of the first section of the tower top is 1001kg / h. The pressure at the top of the first functional section of the reactor was -0.05 kPa, and the pressures in the second, third and fourth functional sections were 2.2 kPa, 4.4 kPa and 4.8 kPa, respectively. At 72 hours, the flow rate of glyphosate slurry produced was 965 kg / h, the reaction conversion rate was 87.1%, and the content of glyphosate technical obtained after crystallization and washing was 96.5%.

[0068] Unsuccessful cases:

[0069] The method and steps of Example 4 are the same as those of Example 1. If the temperature of the heater is too low, resulting in the temperature of the fourth functional stage being lower than the reaction end temperature of 140°C, the glyphosate content in the reaction output is low or even no glyphosate is generated, and the material needs to be returned on site.

[0070] The method steps of Example 5 are the same as those of Example 1. If the temperature of the heater is too high, causing the temperature of the fourth functional section to be higher than the reaction endpoint temperature of 140°C, the material in the fourth functional section will become gelatinous, causing the reaction tower to be blocked, the pressure in the tower to increase, and a safety accident to occur.

[0071] Example 5-1

[0072] After the glyphosate mixed acid liquid enters the first reaction functional section of the acido dealcoholization reactor at a speed of 2500kg / h, the liquid phase enters the second reaction functional section through the filler of the first reaction functional section, and enters the third and fourth reaction functional sections through the downcomer and the bypass overflow pipe in the tower. The height of the overflow pipe is controlled to be slightly lower than the height of the downcomer, and the cross-section of the bypass pipe is the same as the cross-sectional area of ​​the downcomer. After the reaction liquid reacts in the second reaction section for about 1.5 hours, the liquid enters the third reaction functional section through the downcomer and the bypass overflow, and the bypass overflow flow rate is measured to be about 901kg / h; after the reaction liquid reacts in the third reaction section for about 3 hours, the liquid enters the fourth reaction functional section through the downcomer and the bypass overflow, and the bypass overflow flow rate is measured to be about 598kg / h. Right; After about 2 hours of reaction, process water is added to the third and fourth reaction functional sections at a flow rate of 130kg / h, and the flow rate of the second, third and fourth sections of the circulating pump is controlled to 8000kg / h for full circulation of the second, third and fourth sections of the reaction liquid; by controlling the steam volume of the heater, the temperature of the third and fourth sections is controlled to 108℃ and 130℃, and the temperature of the first and second sections is measured to be 55℃ and 84℃; the reaction liquid stays in the acid dealcoholization reactor for 5-7 hours; the gas phase flow rate of the fourth reaction section connected to the third reaction section through the spray device is measured to be 499kg / h, and the gas phase flow rate of the third reaction section connected to the second reaction section through the pipeline is 1219kg / h; the flow rate of the first section of the tail gas pipe at the top of the tower is 1658kg / h. The pressure at the top of the first functional section of the reactor is -0.05kPa, and the pressures in the second, third and fourth functional sections are 2.2kpa, 4.4kpa and 4.8kpa. At 35 days, the flow rate of glyphosate slurry produced was 972 kg / h, the reaction conversion rate was 87.0%, and the content of glyphosate technical obtained after crystallization and washing was 96.4%.

[0073] time Reaction conversion rate (%) Content of glyphosate technical obtained after crystallization and washing (%) 6h 86.1 95.9 12h 86.3 96.1 24h 86.8 96.3 3d 87.0 96.3 7d 87.2 96.4 14d 87.1 96.3 28d 87.1 96.4 35d 87.0 96.4

[0074] Example 5-2

[0075] After the glyphosate mixed acid liquid enters the first reaction functional section of the acido dealcoholization reactor at a speed of 2500kg / h, the liquid phase enters the second reaction functional section through the filler of the first reaction functional section, and enters the third and fourth reaction functional sections through the downcomer and the bottom pipeline in the tower. The flow rate of the bottom pipeline is controlled to be less than 1 / 2 of the flow rate of the cross-sectional area of ​​the downcomer. After the reaction liquid reacts in the second reaction section for about 1.5 hours, the liquid enters the third reaction functional section through the downcomer and the bottom pipeline, and the flow rate of the bottom pipeline is measured to be about 605kg / h; after the reaction liquid reacts in the third reaction section for about 3 hours, the liquid enters the fourth reaction functional section through the downcomer and the bottom pipeline, and the flow rate of the bottom pipeline is measured to be about 395kg / h; after the reaction liquid reacts in the third reaction section for about 2 hours, the liquid enters the fourth reaction functional section through the downcomer and the bottom pipeline, and the flow rate of the bottom pipeline is measured to be about 395kg / h. After 1 hour, process water was added to the third and fourth reaction functional sections at a flow rate of 130 kg / h, and the flow rate of the second, third and fourth sections of the circulating pump was controlled to 8000 kg / h to carry out the full circulation of the second, third and fourth sections of the reaction liquid; the temperature of the third and fourth sections was controlled to 108°C and 130°C by controlling the steam volume of the heater, and the temperature of the first and second sections was measured to be 53°C and 82°C; the reaction liquid stayed in the acid de-alcoholization reactor for 5-7 hours; the gas phase flow rate of the fourth reaction section connected to the third reaction section through the spray device was measured to be 499 kg / h, and the gas phase flow rate of the third reaction section connected to the second reaction section through the pipeline was 1210 kg / h; the flow rate of the first section of the tail gas pipe at the top of the tower was 1652 kg / h. The pressure at the top of the first functional section of the reactor was -0.05 kPa, and the pressures in the second, third and fourth functional sections were 2.2 kPa, 4.4 kPa and 4.8 kPa. At 35 days, the flow rate of glyphosate slurry produced was 978 kg / h, the reaction conversion rate was 86.3%, and the content of glyphosate technical obtained after crystallization and washing was 96.3%.

[0076] Example 5-3

[0077] After the glyphosate mixed acid liquid enters the first reaction functional section of the acido dealcoholization reactor at a speed of 2500kg / h, the liquid phase enters the second reaction functional section through the filler of the first reaction functional section, and enters the third and fourth reaction functional sections through the downcomer, the bypass overflow pipe and the bottom in the tower. The height of the overflow pipe is controlled to be slightly lower than the height of the downcomer, and the cross-sectional area of ​​the bypass pipe is the same as that of the downcomer. The flow rate of the bottom pipe is controlled to be less than 1 / 2 of the flow rate of the cross-sectional area of ​​the downcomer. After the reaction liquid reacts in the second reaction section for about 1.5 hours, the liquid enters the third reaction functional section through the downcomer and the bottom pipe. The bypass pipe flow rate is measured to be 721kg / h, and the bottom pipe flow rate is about 358kg / h. After the reaction liquid reacts in the third reaction section for about 3 hours, the liquid enters the fourth reaction functional section through the downcomer and the bottom pipe. The bypass pipe flow rate is measured to be The pipeline flow rate is 485kg / h, and the bottom pipeline flow rate is about 242kg / h; after about 2 hours of reaction, process water is added to the third and fourth reaction functional sections at a flow rate of 130kg / h, and the flow rate of the second, third and fourth section circulation pumps is controlled to be 8000kg / h for full circulation of the second, third and fourth section reaction liquids; by controlling the steam volume of the heater, the temperature of the third and fourth sections is controlled to be 108℃ and 130℃, and the temperature of the first and second sections is measured to be 53℃ and 83℃; the reaction liquid stays in the acid de-alcoholization reactor for 5-7 hours; the gas phase flow rate of the fourth reaction section connected to the third reaction section through the spray device is measured to be 501kg / h, and the gas phase flow rate of the third reaction section connected to the second reaction section through the pipeline is 1212kg / h; the flow rate of the first section tail gas pipe at the top of the tower is 1658kg / h. The top pressure of the first functional section of the reactor is -0.05kPa, and the pressures in the second, third and fourth functional sections are 2.2kpa, 4.4kpa and 4.8kpa. At 35 days, the flow rate of glyphosate slurry produced was 975 kg / h, the reaction conversion rate was 86.5%, and the content of glyphosate technical obtained after crystallization and washing was 96.4%.

Claims

1. A continuous hydrolysis and acidolysis alcoholization process of glyphosate, characterized in that: The material flow in the continuous hydrolysis acid dealcoholization process includes the following steps: After the glyphosate mixed acid liquid enters the first reaction functional section of the acid de-alcoholization reactor, the liquid phase enters the second reaction functional section through the filler of the first reaction functional section; After the reaction liquid reacts in the second reaction functional section, the liquid phase flows from the overflow plate or the liquid phase pipeline to the Nth reaction functional section; After the reaction liquid reacts in the Nth reaction functional section, the liquid phase flows from the overflow plate or the liquid phase pipeline to the N+1th reaction functional section, and reacts in the N+1th reaction functional section to obtain glyphosate slurry, wherein N is 3; The liquid phase in the second reaction functional section enters the third reaction functional section from the overflow plate and the upper 3 / 5-1 / 8 of the second reaction functional section for reaction; wherein, the flow rate of the second reaction functional section entering the third reaction functional section through the overflow plate is e, and the flow rate of e is 1-100% of c; the flow rate of the upper 3 / 5-1 / 8 of the second reaction functional section entering the third reaction functional section is f, and the flow rate of f is 1-100% of c; and e+f=c, e:f≥0.5; The liquid phase in the third reaction functional section enters the fourth reaction functional section from the overflow plate and the upper 3 / 5-1 / 8 of the third reaction functional section for reaction; wherein, the flow rate of the third reaction functional section from the overflow plate to the fourth reaction functional section is g, and the flow rate of g is 1-100% of d, and the flow rate of the upper 3 / 5-1 / 8 of the third reaction functional section to enter the fourth reaction functional section is h, and the flow rate of h is 1-100% of d, and g+h=d, g:h≥0.5; The temperature in the second reaction functional section is controlled at 60-90°C and the pressure is -20kpa-30kpa; the temperature in the third reaction functional section is controlled at 88-112°C and the pressure is -2-40 kPa; the temperature in the fourth reaction functional section is controlled at 105-140°C and the pressure is -2-100kPa; The glyphosate acidolysis liquid storage tank is connected to the acido dealcoholization reactor, and the acido dealcoholization reactor is provided with a first reaction functional section, a second reaction functional section, a third reaction functional section, and a fourth reaction functional section from top to bottom, and the first reaction functional section is a packing section.

2. The continuous hydrolysis and acid dealcoholization process of glyphosate according to claim 1, characterized in that: The specific gravity of the glyphosate mixed acid solution is 0.92-1.12, and the flow rate of the glyphosate mixed acid solution entering the first reaction functional section of the acid de-alcoholization reactor is a, and the flow rate of a ranges from 1t / h to 150t / h; The flow rate of the reaction liquid entering the second reaction functional section through the filler of the first reaction functional section is b, and the flow rate of b is 80%-100% of a; After the reaction liquid reacts in the second reaction functional section, the liquid phase in the second reaction functional section enters the third reaction functional section at a flow rate c for reaction, and the flow rate c is 50-90% of a; After the reaction liquid reacts in the third reaction functional section, the liquid phase in the third reaction functional section enters the fourth reaction functional section at a flow rate d for reaction, and the flow rate d is 30-70% of a.

3. The continuous hydrolysis and acidolysis alcoholization process of glyphosate according to claim 1, characterized in that: 10-100% volume fraction of the liquid phase in the second reaction functional section is injected into the middle of the second reaction functional section again by the circulation pump to achieve circulation. 10-100% volume fraction of the liquid phase in the third reaction functional section is injected into the heater by the circulation pump for heating and then injected into the middle of the third reaction functional section again by the circulation pump to achieve circulation.

4. The continuous hydrolysis and acidolysis alcoholization process of glyphosate according to claim 1, characterized in that: 10-100% mass fraction of liquid phase in the fourth reaction functional section is pumped into heater 2 through a circulation pump for heating and then injected into the fourth reaction functional section again in a jet manner to achieve circulation. Another route of the circulation pump is connected to the discharge pipeline with a flow rate of q.

5. The continuous hydrolysis and acid dealcoholization process of glyphosate according to any one of claims 1 to 4, characterized in that: Part of the gas phase of the fourth reaction functional section enters the middle of the third reaction functional section in the form of gas injection, and part enters the gas recovery device; part of the gas phase of the third reaction functional section enters the second reaction functional section, and part enters the gas recovery device.

6. The continuous hydrolysis and acid dealcoholization process of glyphosate according to any one of claims 1 to 4, characterized in that: The fourth reaction functional section generates a gas phase flow rate of i, and the flow rate of i is 15-24% of a, wherein: the flow rate j enters the middle part of the third reaction functional section in the form of gas injection, and the flow rate of j is 0-100% of i; the flow rate k is connected to the gas recovery device by a gas phase pipeline, and the flow rate of k is 0-100% of i, j+k=i.

7. The continuous hydrolysis and acid dealcoholization process of glyphosate according to any one of claims 1 to 4, characterized in that: The third reaction functional section generates a gas phase flow rate of m, wherein: the flow rate n enters the middle of the second reaction functional section in the form of gas injection, the flow rate of n is 0-100% of m, the flow rate p is connected to the gas recovery device by a gas phase pipeline, the flow rate of p is 0-100% of m, and n+p=m.

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