glyphosate solvent recovery unit

Abstract

This utility model discloses a glyphosate solvent recovery device, comprising a first column reboiler, a first light component tank, a first heat pump, a first reboiler, a first buffer tank, a transfer pump, a second column reboiler, a second light component tank, a second heat pump, a second reboiler, and a second buffer tank. The first column reboiler is used to receive alkaline methanol and perform distillation separation on it. The first light component tank is connected to the top gas phase outlet of the first column reboiler and is used to receive methylal and chloromethane separated in the first column reboiler. The inlet of the first heat pump is connected to the first light component tank, the outlet of the first heat pump is connected to the heating medium inlet of the first reboiler, the heating medium outlet of the first reboiler is connected to the inlet of the first buffer tank, and the material inlet of the first reboiler is connected to the bottom liquid phase outlet of the first column reboiler. This utility model can save energy consumption and reduce energy costs.

Description

Technical Field

[0001] This utility model relates to a glyphosate solvent recovery device. Background Technology

[0002] Currently, in the glycine-based glyphosate production process, the components generated in the hydrolysis gas phase include methanol, methyl acetal, chloromethane, water, and hydrogen chloride. These components undergo primary circulating water condensation and primary cooling at 5 degrees Celsius to obtain acidic methanol, which contains 49.43% methanol, 11.23% methyl acetal, 38.26% water, 0.56% hydrogen chloride, and 0.5% chloromethane. The acidic methanol is then neutralized with liquid alkali, and the pH is controlled between 9 and 10 to obtain alkaline methanol, which contains 49.12% methanol, 10.66% methyl acetal, 38.8% water, 0.92% sodium chloride, and 0.5% chloromethane. Then, a recovery system is needed to separate and recover the components in the aforementioned alkali methanol. In the recovery system, the material in the distillation column needs to be heated by a reboiler to vaporize and rise the light components in the material, thereby achieving separation. The heat source of the reboiler relies on a large amount of high-temperature steam. For example, Chinese patent CN115367944B discloses an energy-saving recovery process for formaldehyde concentration in glyphosate production wastewater and the formaldehyde removal tower used therein, which relies on a large amount of high-temperature steam to provide heat to the reboiler. This will result in the consumption of a large amount of high-temperature steam during the recovery process, leading to huge energy consumption and excessively high energy costs. Utility Model Content

[0003] The technical problem to be solved by this utility model is to overcome the defects of the prior art and provide a glyphosate solvent recovery device that can save energy consumption and reduce energy costs.

[0004] To solve the above-mentioned technical problems, the technical solution of this utility model is: a glyphosate solvent recovery device, comprising a first tower bottom, a first light component tank, a first heat pump, a first reboiler, a first buffer tank, a transfer pump, a second tower bottom, a second light component tank, a second heat pump, a second reboiler, and a second buffer tank;

[0005] The first column bottom is used to feed in alkaline methanol and to perform distillation separation of alkaline methanol;

[0006] The first light component tank is connected to the top gas phase outlet of the first column bottom and is used to receive the methyl acetal and chloromethane separated in the first column bottom;

[0007] The inlet of the first heat pump is connected to the first light component tank, the outlet of the first heat pump is connected to the heating medium inlet of the first reboiler, and the heating medium outlet of the first reboiler is connected to the inlet of the first buffer tank.

[0008] The material inlet of the first reboiler is connected to the bottom liquid phase outlet of the first column, and the material outlet of the first reboiler is connected to the first column.

[0009] The inlet of the transfer pump is connected to the bottom liquid outlet of the first column, and the outlet of the transfer pump is connected to the second column. The transfer pump is used to pump the heavy component material separated in the first column to the second column for distillation separation.

[0010] The second light component tank is connected to the top gas phase outlet of the second column and is used to receive the methanol separated in the second column.

[0011] The inlet of the second heat pump is connected to the second light component tank, the outlet of the second heat pump is connected to the heating medium inlet of the second reboiler, and the heating medium outlet of the second reboiler is connected to the inlet of the second buffer tank.

[0012] The material inlet of the second reboiler is connected to the bottom liquid phase outlet of the second column, and the material outlet of the second reboiler is connected to the second column.

[0013] Furthermore, the glyphosate solvent recovery device also includes a feed pump, a preheater, and a wastewater pump;

[0014] The inlet of the wastewater pump is connected to the bottom liquid outlet of the second tower, and the outlet of the wastewater pump is connected to the medium inlet of the preheater. The wastewater pump is used to pump the separated wastewater in the second tower to the medium inlet of the preheater so that the wastewater is discharged from the medium outlet of the preheater.

[0015] The outlet of the feed pump is connected to the material inlet of the preheater, and the material outlet of the preheater is connected to the first column bottom. The feed pump is used to pump the alkali methanol to the preheater for heat exchange and heating, and then allow the alkali methanol to flow into the first column bottom for distillation and separation.

[0016] Furthermore, the medium outlet of the preheater is connected to the wastewater treatment plant.

[0017] Furthermore, the glyphosate solvent recovery device also includes a first pressure reducing valve, a first condenser, and a first storage tank;

[0018] The outlet of the first buffer tank is connected to the inlet of the first pressure reducing valve, and the outlet of the first pressure reducing valve is connected to the material inlet of the first condenser. The methylal and chloromethane in the first buffer tank are used to flow into the first pressure reducing valve for pressure reduction and then flow into the first condenser for condensation and liquefaction.

[0019] The material outlet of the first condenser is connected to the first storage tank so that the condensed and liquefied methyl acetal in the first condenser is discharged into the first storage tank for storage.

[0020] The gas phase outlet of the first condenser is used to discharge uncondensed and liquefied chloromethane gas from the first condenser.

[0021] Furthermore, the glyphosate solvent recovery device also includes a gas-liquid separator;

[0022] The inlet of the gas-liquid separator is connected to the gas phase outlet of the first condenser so that the uncondensed and liquefied chloromethane gas in the first condenser flows into the gas-liquid separator.

[0023] The gas phase outlet of the gas-liquid separator is used to discharge chloromethane gas, and the liquid phase outlet of the gas-liquid separator is connected to the first storage tank.

[0024] Furthermore, the glyphosate solvent recovery device also includes a first discharge pump and a first discharge pipeline. The inlet of the first discharge pump is connected to the outlet of the first storage tank, and the outlet of the first discharge pump is connected to the first discharge pipeline. The first discharge pump is used to pump and discharge methylal from the first storage tank through the first discharge pipeline.

[0025] Furthermore, the glyphosate solvent recovery device also includes a first reflux pipeline, the outlet of the first discharge pump is connected to the first reflux pipeline, the first reflux pipeline is connected to the reflux port of the first tower bottom, and the first discharge pump is used to pump methylal from the first storage tank and return a portion of the methylal from the first reflux pipeline to the first tower bottom.

[0026] Furthermore, the glyphosate solvent recovery device also includes a second pressure reducing valve, a second condenser, and a second storage tank;

[0027] The outlet of the second buffer tank is connected to the inlet of the second pressure reducing valve, the outlet of the second pressure reducing valve is connected to the material inlet of the second condenser, the material outlet of the second condenser is connected to the second storage tank, and the methanol in the second buffer tank is used to flow into the second pressure reducing valve for pressure reduction, then flow into the second condenser for condensation and liquefaction, and finally flow into the second storage tank for storage.

[0028] Furthermore, the glyphosate solvent recovery device also includes a second discharge pump and a second discharge pipeline. The inlet of the second discharge pump is connected to the outlet of the second storage tank, and the outlet of the second discharge pump is connected to the second discharge pipeline. The second discharge pump is used to pump methanol from the second storage tank out of the second discharge pipeline.

[0029] Furthermore, the glyphosate solvent recovery device also includes a second reflux pipeline, the outlet of the second discharge pump is also connected to the second reflux pipeline, the second reflux pipeline is connected to the reflux port of the second tower bottom, and the second discharge pump is used to pump methanol in the second storage tank and return a portion of the methanol from the second reflux pipeline to the second tower bottom.

[0030] After adopting the above technical solution, the alkali methanol is first introduced into the first column reboiler and then subjected to atmospheric pressure distillation separation. The temperature at the top of the first column reboiler is controlled at 43-46℃, and the temperature at the bottom of the first column reboiler is controlled at 83-86℃. The light component material separated in the first column reboiler flows into the first light component tank. The light component material flowing into the first light component tank is gaseous and contains 85-95% methylal, a small amount of chloromethane, and water. The methylal and chloromethane in the first light component tank are pressurized and heated to 1.0-1.5MPa and 95-130℃ by the first heat pump, and then flow into the first reboiler and then into the first buffer tank. At the same time, the heavy component material at the bottom of the first column reboiler flows into the first reboiler and then flows back into the first column reboiler. Therefore, the methylal and chloromethane gases, after being pressurized and heated in the first reboiler, can heat the heavy component material at the bottom of the first column reboiler through heat exchange. Therefore, the heat of the first reboiler comes from the heat in gases such as methylal and chloromethane. On the one hand, the energy consumption is low when the first heat pump pressurizes and heats the methylal and chloromethane. On the other hand, it makes full use of the latent heat and sensible heat of vaporization of methylal and chloromethane when they vaporize in the first reboiler. The heat in the methylal and chloromethane is used to heat the heavy components flowing through the first reboiler. There is no need to introduce a large amount of high-temperature steam into the first reboiler to provide heat energy, which greatly saves the amount of high-temperature steam used, reduces energy consumption, and saves energy costs.

[0031] Furthermore, the heavy component material at the bottom of the first column reboiler consists of methanol, water, and sodium chloride. Activating the transfer pump allows this heavy component material to be pumped to the second column reboiler for atmospheric pressure distillation separation. The temperature at the top of the second column reboiler is controlled at 64–67°C, and the temperature at the bottom is controlled at 105–108°C. The light component material separated in the second column reboiler flows into the second light component tank, where the methanol content is ≥99.5%. Then, the methanol gas in the second light component tank flows through the second heat pump, where it is pressurized and heated to 1.0–1.5 MPa and 100–150°C. The methanol gas then flows through the second reboiler and then into the second buffer tank. Meanwhile, the heavy component material at the bottom of the second column reboiler also flows into the second reboiler and then back into the second column reboiler. Therefore, the pressurized and heated methanol gas in the second reboiler can heat the heavy component material at the bottom of the second column reboiler through heat exchange. Therefore, the heat of the second reboiler comes from the heat in the methanol gas. On the one hand, the energy consumption is low when pressurizing and heating the methanol gas through the second heat pump. On the other hand, it makes full use of the latent heat and sensible heat of vaporization of methanol in the second tower. The heat in the methanol gas is used to heat the heavy component material flowing through the second reboiler. There is no need to introduce a large amount of high-temperature steam into the second reboiler to provide heat energy, thereby saving the amount of high-temperature steam used, reducing energy consumption, and saving energy costs. Attached Figure Description

[0032] Figure 1 This is a process flow diagram of the glyphosate solvent recovery device of this utility model;

[0033] In the diagram: 1. First reboiler; 2. First light component tank; 3. First heat pump; 4. First reboiler; 5. First buffer tank; 6. Transfer pump; 7. Second reboiler; 8. Second light component tank; 9. Second heat pump; 10. Second reboiler; 11. Second buffer tank; 12. Feed pump; 13. Preheater; 14. Wastewater pump; 15. First pressure reducing valve; 16. First condenser; 17. First storage tank; 18. Gas-liquid separator; 19. First discharge pump; 20. First discharge pipeline; 21. First reflux pipeline; 22. Second pressure reducing valve; 23. Second condenser; 24. Second storage tank; 25. Second discharge pump; 26. Second discharge pipeline; 27. Second reflux pipeline. Detailed Implementation

[0034] To make the content of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0035] like Figure 1As shown, a glyphosate solvent recovery device includes a first reboiler 1, a first light component tank 2, a first heat pump 3, a first reboiler 4, a first buffer tank 5, a transfer pump 6, a second reboiler 7, a second light component tank 8, a second heat pump 9, a second reboiler 10, and a second buffer tank 11.

[0036] The first column bottom 1 is used to feed in alkaline methanol and to perform distillation separation of alkaline methanol;

[0037] The first light component tank 2 is connected to the top gas phase outlet of the first column reactor 1 and is used to receive the methyl acetal and chloromethane separated in the first column reactor 1;

[0038] The inlet of the first heat pump 3 is connected to the first light component tank 2, the outlet of the first heat pump 3 is connected to the heating medium inlet of the first reboiler 4, and the heating medium outlet of the first reboiler 4 is connected to the inlet of the first buffer tank 5, so that the gaseous methyl acetal and gaseous chloromethane in the first light component tank 2 flow into the first heat pump 3 for pressurization and heating, then flow through the first reboiler 4 and then into the first buffer tank 5.

[0039] The material inlet of the first reboiler 4 is connected to the liquid phase outlet at the bottom of the first column 1, and the material outlet of the first reboiler 4 is connected to the first column 1, so that the heavy component material at the bottom of the first column 1 flows into the first reboiler 4 for heat exchange and heating and then flows back into the first column 1.

[0040] The inlet of the transfer pump 6 is connected to the bottom liquid outlet of the first column 1, and the outlet of the transfer pump 6 is connected to the second column 7. The transfer pump 6 is used to pump the heavy component material separated in the first column 1 to the second column 7 for distillation separation.

[0041] The second light component tank 8 is connected to the top gas phase outlet of the second column bottom 7 and is used to receive the methanol separated in the second column bottom 7;

[0042] The inlet of the second heat pump 9 is connected to the second light component tank 8, the outlet of the second heat pump 9 is connected to the heating medium inlet of the second reboiler 10, and the heating medium outlet of the second reboiler 10 is connected to the inlet of the second buffer tank 11, so that the gaseous methanol in the second light component tank 8 flows into the second heat pump 9 for pressurization and heating, then flows through the second reboiler 10 and then into the second buffer tank 11.

[0043] The material inlet of the second reboiler 10 is connected to the liquid outlet at the bottom of the second reboiler 7, and the material outlet of the second reboiler 10 is connected to the second reboiler 7, so that the heavy components at the bottom of the second reboiler 7 flow into the second reboiler 10 for heat exchange and heating before flowing back into the second reboiler 7. Both the first reboiler 1 and the second reboiler 7 can be distillation columns.

[0044] Specifically, after the alkali methanol is introduced into the first reboiler 1, it undergoes atmospheric pressure distillation separation. The temperature at the top of the first reboiler 1 is controlled at 43-46°C, and the temperature at the bottom of the first reboiler 1 is controlled at 83-86°C. The light component material separated in the first reboiler 1 flows into the first light component tank 2. The light component material flowing into the first light component tank 2 is gaseous and contains 85-95% methylal, a small amount of chloromethane, and water. The methylal and chloromethane in the first light component tank 2 are pressurized and heated to 1.0-1.5 MPa and 95-130°C by the first heat pump 3, and then flow into the first reboiler 4 and then into the first buffer tank 5. At the same time, the heavy component material at the bottom of the first reboiler 1 flows into the first reboiler 4 and then flows back into the first reboiler 1. Therefore, the methylal and chloromethane gases, after being pressurized and heated in the first reboiler 4, can heat the heavy component material at the bottom of the first reboiler 1 through heat exchange. Therefore, the heat of the first reboiler 4 comes from the heat in gases such as methylal and chloromethane. On the one hand, the energy consumption is low when the first heat pump 3 pressurizes and heats the methylal and chloromethane. On the other hand, it makes full use of the latent heat and sensible heat of vaporization of methylal and chloromethane when they vaporize in the first reboiler 1. The heat in the methylal and chloromethane is used to heat the heavy component material flowing through the first reboiler 4. It is not necessary to introduce a large amount of high-temperature steam into the first reboiler 4 to provide heat energy, thereby greatly saving the amount of high-temperature steam used, reducing energy consumption, and saving energy costs.

[0045] More specifically, the heavy component material at the bottom of the first reboiler 1 includes methanol, water, and sodium chloride. Activating the transfer pump 6 allows the heavy component material at the bottom of the first reboiler 1 to be pumped to the second reboiler 7 for atmospheric pressure distillation separation. The temperature at the top of the second reboiler 7 is controlled at 64–67°C, and the temperature at the bottom of the second reboiler 7 is controlled at 105–108°C. The light component material separated in the second reboiler 7 flows into the second light component tank 8, and the methanol content in the light component material flowing into the second light component tank 8 is ≥99.5%. Then, the methanol gas in the second light component tank 8 flows through the second heat pump 9, where it is pressurized and heated to 1.0–1.5 MPa and 100–150°C. The methanol gas then flows through the second reboiler 10 and then into the second buffer tank 11. Meanwhile, the heavy component material at the bottom of the second reboiler 7 also flows into the second reboiler 10 and then back into the second reboiler 7. Therefore, the pressurized and heated methanol gas in the second reboiler 10 can heat the heavy component material at the bottom of the second reboiler 7 through heat exchange. Thus, the heat of the second reboiler 10 comes from the heat in the methanol gas. On the one hand, the energy consumption for pressurizing and heating the methanol gas through the second heat pump 9 is low; on the other hand, it fully utilizes the latent heat and sensible heat of vaporization of methanol in the second reboiler 7. The heat in the methanol gas is used to heat the heavy component material flowing through the second reboiler 10, eliminating the need to introduce a large amount of high-temperature steam into the second reboiler 10 to provide heat energy, thereby saving the amount of high-temperature steam used, reducing energy consumption, and saving energy costs. The specific structures of the first heat pump 3 and the second heat pump 9 are existing technologies well known to those skilled in the art, and will not be described in detail in this embodiment.

[0046] like Figure 1 As shown, the glyphosate solvent recovery device may also include a feed pump 12, a preheater 13, and a wastewater pump 14;

[0047] The inlet of the wastewater pump 14 is connected to the bottom liquid outlet of the second tower bottom 7, and the outlet of the wastewater pump 14 is connected to the medium inlet of the preheater 13. The wastewater pump 14 is used to pump the separated wastewater in the second tower bottom 7 to the medium inlet of the preheater 13 so that the wastewater is discharged from the medium outlet of the preheater 13.

[0048] The outlet of the feed pump 12 is connected to the material inlet of the preheater 13, and the material outlet of the preheater 13 is connected to the first column bottom 1. The feed pump 12 is used to pump the alkali methanol to the preheater 13 for heat exchange and heating, and then let the alkali methanol flow into the first column bottom 1 for distillation and separation.

[0049] Specifically, the medium outlet of the preheater 13 is connected to the wastewater treatment plant. In the preheater 13, the alkali methanol exchanges heat with the wastewater, and the alkali methanol is heated and then flows into the first tower reactor 1, while the wastewater flows into the wastewater treatment plant for treatment, thus fully utilizing the residual heat in the wastewater. The specific structure of the preheater 13 is prior art well known to those skilled in the art, and will not be described in detail in this embodiment.

[0050] like Figure 1 As shown, the glyphosate solvent recovery device may further include a first pressure reducing valve 15, a first condenser 16, and a first storage tank 17;

[0051] The outlet of the first buffer tank 5 is connected to the inlet of the first pressure reducing valve 15, and the outlet of the first pressure reducing valve 15 is connected to the material inlet of the first condenser 16. The methylal and chloromethane in the first buffer tank 5 are used to flow into the first pressure reducing valve 15 for pressure reduction and then flow into the first condenser 16 for condensation and liquefaction.

[0052] The material outlet of the first condenser 16 is connected to the first storage tank 17 so that the condensed and liquefied methyl acetal in the first condenser 16 is discharged into the first storage tank 17 for storage.

[0053] The gas phase outlet of the first condenser 16 is used to discharge the uncondensed and liquefied chloromethane gas in the first condenser 16.

[0054] like Figure 1 As shown, the glyphosate solvent recovery device may further include a gas-liquid separator 18;

[0055] The inlet of the gas-liquid separator 18 is connected to the gas phase outlet of the first condenser 16 so that the uncondensed chloromethane gas in the first condenser 16 flows into the gas-liquid separator 18.

[0056] The gas phase outlet of the gas-liquid separator 18 is used to discharge chloromethane gas, and the liquid phase outlet of the gas-liquid separator 18 is connected to the first storage tank 17. Specifically, the methylal and chloromethane flowing into the first buffer tank 5 will flow into the first pressure reducing valve 15 for pressure reduction and then flow into the first condenser 16 for condensation and liquefaction. The temperature in the first condenser 16 is controlled so that the methylal is condensed and liquefied while the chloromethane remains in a gaseous state. The liquefied methylal will be discharged from the material outlet of the first condenser 16 into the first storage tank 17 for storage, while the chloromethane gas that has not been condensed and liquefied in the first condenser 16 will be discharged from the gas phase outlet of the first condenser 16 into the gas-liquid separator 18 for gas-liquid separation. The separated chloromethane gas will be discharged from the gas phase outlet of the gas-liquid separator 18 to the chloromethane workshop for further recovery, while the separated liquid will be discharged from the liquid phase outlet of the gas-liquid separator 18 into the first storage tank.

[0057] like Figure 1 As shown, the glyphosate solvent recovery device may further include a first discharge pump 19 and a first discharge pipeline 20. The inlet of the first discharge pump 19 is connected to the outlet of the first storage tank 17, and the outlet of the first discharge pump 19 is connected to the first discharge pipeline 20. The first discharge pump 19 is used to pump and discharge methylal from the first storage tank 17 through the first discharge pipeline 20.

[0058] like Figure 1 As shown, the glyphosate solvent recovery device may further include a first reflux pipeline 21, the outlet of the first discharge pump 19 is also connected to the first reflux pipeline 21, the first reflux pipeline 21 is connected to the reflux port of the first tower bottom 1, the first discharge pump 19 is used to pump methylal in the first storage tank 17 and return part of the methylal from the first reflux pipeline 21 to the first tower bottom 1; specifically, by pumping methylal stored in the first storage tank 17 through the first discharge pump 19, a portion of the methylal is pumped out from the first discharge pipeline 20, and another portion of the methylal is returned from the first reflux pipeline 21 to the first tower bottom 1 as reflux liquid.

[0059] like Figure 1 As shown, the glyphosate solvent recovery device may further include a second pressure reducing valve 22, a second condenser 23, and a second storage tank 24;

[0060] The outlet of the second buffer tank 11 is connected to the inlet of the second pressure reducing valve 22, the outlet of the second pressure reducing valve 22 is connected to the material inlet of the second condenser 23, and the material outlet of the second condenser 23 is connected to the second storage tank 24. The methanol in the second buffer tank 11 is used to flow into the second pressure reducing valve 22 for pressure reduction, then into the second condenser 23 for condensation and liquefaction, and finally into the second storage tank 24 for storage. Specifically, the methanol flowing into the second buffer tank 11 will flow into the second pressure reducing valve 22 for pressure reduction and then into the second condenser 23 for condensation and liquefaction. The liquefied methanol will be discharged from the material outlet of the second condenser 23 into the second storage tank 24 for storage.

[0061] like Figure 1 As shown, the glyphosate solvent recovery device may further include a second discharge pump 25 and a second discharge pipeline 26. The inlet of the second discharge pump 25 is connected to the outlet of the second storage tank 24, and the outlet of the second discharge pump 25 is connected to the second discharge pipeline 26. The second discharge pump 25 is used to pump and discharge methanol in the second storage tank 24 from the second discharge pipeline 26.

[0062] like Figure 1As shown, the glyphosate solvent recovery device may further include a second reflux pipeline 27, the outlet of the second discharge pump 25 is also connected to the second reflux pipeline 27, the second reflux pipeline 27 is connected to the reflux port of the second tower bottom 7, the second discharge pump 25 is used to pump methanol in the second storage tank 24 and return a portion of the methanol from the second reflux pipeline 27 to the second tower bottom 7; specifically, the second discharge pump 25 can pump methanol stored in the second storage tank 24 so that a portion of the methanol is pumped out from the second discharge pipeline 26, and a portion of the methanol flows back to the second tower bottom 7 from the second reflux pipeline 27 as reflux liquid.

[0063] Specifically, the glyphosate solvent recovery device of this application embodiment requires a small amount of high-temperature steam to be introduced into the first reboiler 4 from the heating medium inlet and a small amount of high-temperature steam to be introduced into the second reboiler 10 from the heating medium inlet to ensure the heat source supply during startup. Once normal operation begins, it is no longer necessary to introduce high-temperature steam into the first reboiler 4 and the second reboiler 10. According to actual calculations, after adopting the glyphosate solvent recovery device of this application embodiment, the high-temperature steam required per ton of glyphosate decreased from the original 3.5 tons to 0.5 tons, while the electricity required per ton of glyphosate increased by 200 kWh. Based on an electricity price of 0.5 yuan / kWh and a high-temperature steam price of 200 yuan / ton, the energy cost saved per ton of glyphosate is (3.5 - 0.5) × 200 - 200 × 0.5 = 500 yuan. Based on an annual glyphosate production of 120,000 tons, the annual energy cost savings are 500 × 120,000 = 60 million yuan.

[0064] In summary, after the alkali methanol is introduced into the first reboiler 1, it undergoes atmospheric pressure distillation separation. The temperature at the top of the first reboiler 1 is controlled at 43-46℃, and the temperature at the bottom of the first reboiler 1 is controlled at 83-86℃. The light component material separated in the first reboiler 1 flows into the first light component tank 2. The light component material flowing into the first light component tank 2 is gaseous and contains 85-95% methylal, a small amount of chloromethane, and water. The methylal and chloromethane in the first light component tank 2 are pressurized and heated to 1.0-1.5MPa and 95-130℃ by the first heat pump 3, and then flow into the first reboiler 4 and then into the first buffer tank 5. At the same time, the heavy component material at the bottom of the first reboiler 1 flows into the first reboiler 4 and then flows back into the first reboiler 1. Therefore, the methylal and chloromethane gases, after being pressurized and heated in the first reboiler 4, can heat the heavy component material at the bottom of the first reboiler 1 through heat exchange. Therefore, the heat of the first reboiler 4 comes from the heat in gases such as methylal and chloromethane. On the one hand, the energy consumption is low when the first heat pump 3 pressurizes and heats the methylal and chloromethane. On the other hand, it makes full use of the latent heat and sensible heat of vaporization of methylal and chloromethane when they vaporize in the first reboiler 1. The heat in the methylal and chloromethane is used to heat the heavy component material flowing through the first reboiler 4. It is not necessary to introduce a large amount of high-temperature steam into the first reboiler 4 to provide heat energy, thereby greatly saving the amount of high-temperature steam used, reducing energy consumption, and saving energy costs.

[0065] Furthermore, the heavy component material at the bottom of the first reboiler 1 consists of methanol, water, and sodium chloride. Activating the transfer pump 6 allows the heavy component material at the bottom of the first reboiler 1 to be pumped to the second reboiler 7 for atmospheric pressure distillation separation. The temperature at the top of the second reboiler 7 is controlled at 64–67°C, and the temperature at the bottom of the second reboiler 7 is controlled at 105–108°C. The light component material separated in the second reboiler 7 flows into the second light component tank 8, where the methanol content is ≥99.5%. Then, the methanol gas in the second light component tank 8 flows through the second heat pump 9, where it is pressurized and heated to 1.0–1.5 MPa and 100–150°C. The methanol gas then flows through the second reboiler 10 and then into the second buffer tank 11. Meanwhile, the heavy component material at the bottom of the second reboiler 7 also flows into the second reboiler 10 and then back into the second reboiler 7. Therefore, the pressurized and heated methanol gas in the second reboiler 10 can heat the heavy component material at the bottom of the second reboiler 7 through heat exchange. Thus, the heat of the second reboiler 10 comes from the heat in the methanol gas. On the one hand, the energy consumption for pressurizing and heating the methanol gas through the second heat pump 9 is low; on the other hand, it fully utilizes the latent heat and sensible heat of vaporization of methanol in the second reboiler 7. The heat in the methanol gas is used to heat the heavy component material flowing through the second reboiler 10, eliminating the need to introduce a large amount of high-temperature steam into the second reboiler 10 to provide heat energy, thereby saving the amount of high-temperature steam used, reducing energy consumption, and saving energy costs.

[0066] The specific embodiments described above further illustrate the technical problems, technical solutions, and beneficial effects of this utility model. It should be understood that the above descriptions are merely specific embodiments of this utility model and are not intended to limit this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A glyphosate solvent recovery apparatus characterized by comprising: It includes a first reboiler (1), a first light component tank (2), a first heat pump (3), a first reboiler (4), a first buffer tank (5), a transfer pump (6), a second reboiler (7), a second light component tank (8), a second heat pump (9), a second reboiler (10), and a second buffer tank (11); The first column bottom (1) is used to feed in alkali methanol and to perform distillation separation of alkali methanol; The first light component tank (2) is connected to the top gas phase outlet of the first column (1) and is used to feed the methyl acetal and chloromethane separated in the first column (1); The inlet of the first heat pump (3) is connected to the first light component tank (2), the outlet of the first heat pump (3) is connected to the heating medium inlet of the first reboiler (4), and the heating medium outlet of the first reboiler (4) is connected to the inlet of the first buffer tank (5). The material inlet of the first reboiler (4) is connected to the bottom liquid outlet of the first column (1), and the material outlet of the first reboiler (4) is connected to the first column (1). The inlet of the transfer pump (6) is connected to the bottom liquid outlet of the first column (1), and the outlet of the transfer pump (6) is connected to the second column (7). The transfer pump (6) is used to pump the heavy component material separated in the first column (1) to the second column (7) for distillation separation. The second light component tank (8) is connected to the top gas phase outlet of the second column (7) and is used to feed the methanol separated in the second column (7); The inlet of the second heat pump (9) is connected to the second light component tank (8), the outlet of the second heat pump (9) is connected to the heating medium inlet of the second reboiler (10), and the heating medium outlet of the second reboiler (10) is connected to the inlet of the second buffer tank (11). The material inlet of the second reboiler (10) is connected to the bottom liquid outlet of the second column bottom (7), and the material outlet of the second reboiler (10) is connected to the second column bottom (7).

2. The glyphosate solvent recovery apparatus according to claim 1, characterized in that, It also includes a feed pump (12), a preheater (13), and a wastewater pump (14); The inlet of the wastewater pump (14) is connected to the bottom liquid outlet of the second tower (7), and the outlet of the wastewater pump (14) is connected to the medium inlet of the preheater (13). The wastewater pump (14) is used to pump the separated wastewater in the second tower (7) to the medium inlet of the preheater (13) so that the wastewater is discharged from the medium outlet of the preheater (13). The outlet of the feed pump (12) is connected to the material inlet of the preheater (13), and the material outlet of the preheater (13) is connected to the first column bottom (1). The feed pump (12) is used to pump the alkali methanol to the preheater (13) for heat exchange and heating, and then let the alkali methanol flow into the first column bottom (1) for distillation and separation.

3. The glyphosate solvent recovery apparatus according to claim 2, wherein The media outlet of the preheater (13) is connected to the sewage treatment plant.

4. The glyphosate solvent recovery apparatus of claim 1, wherein It also includes a first pressure reducing valve (15), a first condenser (16), and a first storage tank (17); The outlet of the first buffer tank (5) is connected to the inlet of the first pressure reducing valve (15), and the outlet of the first pressure reducing valve (15) is connected to the material inlet of the first condenser (16). The methylal and chloromethane in the first buffer tank (5) are used to flow into the first pressure reducing valve (15) for pressure reduction and then flow into the first condenser (16) for condensation and liquefaction. The material outlet of the first condenser (16) is connected to the first storage tank (17) so that the condensed and liquefied methyl acetal in the first condenser (16) is discharged into the first storage tank (17) for storage. The gas phase outlet of the first condenser (16) is used to discharge the uncondensed liquefied chloromethane gas in the first condenser (16).

5. The glyphosate solvent recovery apparatus of claim 4, wherein, It also includes a gas-liquid separator (18); The inlet of the gas-liquid separator (18) is connected to the gas phase outlet of the first condenser (16) so that the uncondensed chloromethane gas in the first condenser (16) flows into the gas-liquid separator (18). The gas phase outlet of the gas-liquid separator (18) is used to discharge chloromethane gas, and the liquid phase outlet of the gas-liquid separator (18) is connected to the first storage tank (17).

6. The glyphosate solvent recovery apparatus of claim 4, wherein, It also includes a first discharge pump (19) and a first discharge pipeline (20). The inlet of the first discharge pump (19) is connected to the outlet of the first storage tank (17), and the outlet of the first discharge pump (19) is connected to the first discharge pipeline (20). The first discharge pump (19) is used to pump and discharge methylal from the first storage tank (17) through the first discharge pipeline (20).

7. The glyphosate solvent recovery apparatus of claim 6, wherein, It also includes a first reflux line (21), the outlet of the first discharge pump (19) is also connected to the first reflux line (21), the first reflux line (21) is connected to the reflux port of the first tower bottom (1), and the first discharge pump (19) is used to pump methyl acetal in the first storage tank (17) and cause part of the methyl acetal to flow back from the first reflux line (21) to the first tower bottom (1).

8. The glyphosate solvent recovery apparatus of claim 1, wherein, It also includes a second pressure reducing valve (22), a second condenser (23), and a second storage tank (24); The outlet of the second buffer tank (11) is connected to the inlet of the second pressure reducing valve (22), the outlet of the second pressure reducing valve (22) is connected to the material inlet of the second condenser (23), the material outlet of the second condenser (23) is connected to the second storage tank (24), and the methanol in the second buffer tank (11) is used to flow into the second pressure reducing valve (22) for pressure reduction, then flow into the second condenser (23) for condensation and liquefaction, and finally flow into the second storage tank (24) for storage.

9. The glyphosate solvent recovery apparatus of claim 8, wherein, It also includes a second discharge pump (25) and a second discharge pipeline (26). The inlet of the second discharge pump (25) is connected to the outlet of the second storage tank (24), and the outlet of the second discharge pump (25) is connected to the second discharge pipeline (26). The second discharge pump (25) is used to pump methanol from the second storage tank (24) out of the second discharge pipeline (26).

10. The glyphosate solvent recovery apparatus of claim 9, wherein, It also includes a second reflux line (27), the outlet of the second discharge pump (25) is also connected to the second reflux line (27), the second reflux line (27) is connected to the reflux port of the second tower bottom (7), and the second discharge pump (25) is used to pump methanol in the second storage tank (24) and cause part of the methanol to flow back from the second reflux line (27) to the second tower bottom (7).

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