Hydrosolvent distillation, compression and separation device

Abstract

The invention discloses a hydrosolvent distillation, compression and separation device, which belongs to the technical field of chemical separation and comprises a reaction kettle, a gas-liquid separator, a low-pressure balance tank, a high-pressure balance tank, a low-pressure steam purification filter, a steam compressor, a steam boiler, an electric cabinet and a condensed water heat recoverer. The steam compressor sucks steam of a water solvent, reduces pressure in the reaction kettle and promotes evaporation of the water solvent in the reaction kettle, the steam compressor compresses the steam of the water solvent into high-temperature and high-pressure steam to enter a heating layer of the reaction kettle, and extract and a solvent in the reaction kettle are condensed into liquid to flow out while being heated; the energy consumption of the device is 20% of the energy consumption of a distillation cooling device, and compared with the distillation cooling device, the energy consumption can be reduced by 80%.

Description

Technical Field

[0001] This invention belongs to the field of chemical separation technology, and particularly relates to the field of distillation separation technology of water solvents. It is mainly used in the recovery and recycling of latent heat of vaporization in the distillation separation of water solvents in chemical and pharmaceutical enterprises. Background Technology

[0002] In the distillation and cooling process of solvents in chemical and pharmaceutical companies, it is necessary to separate the aqueous solvent from the extract. Currently, the common method is distillation and cooling: the solvent is heated to its boiling point to generate steam, and then the latent heat of vaporization of the solvent vapor is dissipated, so that the solvent vapor cools and condenses into a liquid and is separated from the extract.

[0003] In this process, the heat energy required to raise 1 kg of water from 20℃ to 100℃ is 334.88 kJ, while the heat energy required to form 1 kg of water into 100℃ steam is 2257.9 kJ. That is, 85.2% of the heat energy is consumed in the latent heat of vaporization of the solvent evaporation (1-334.88 / 2257.9=0.852), and this part of the heat energy is released into the atmosphere through the cooling tower, wasting a lot of heat energy.

[0004] As those skilled in the art know, if the latent heat of vaporization of the solvent is recovered and recycled, the energy consumption in solvent distillation and separation can be significantly reduced. Summary of the Invention

[0005] To address the high energy consumption caused by the dissipation of the latent heat of vaporization of solvents in existing solvent distillation and cooling production processes, this invention provides a solvent distillation compression separation device.

[0006] In the distillation and compression separation device, the steam compressor draws in the vapor of the water solvent in the reaction vessel. By reducing the pressure of the vapor in the reaction vessel, the boiling point of the water solvent is lowered. The compressor compresses the drawn-in water vapor into high-temperature and high-pressure steam for heating the reaction vessel, causing the solvent in the reaction vessel to boil further. At the same time, the steam from the compressor condenses into a high-temperature liquid. The high-temperature liquid is converted into a low-temperature liquid by the condensate heat recovery device and discharged from the condensate drain, thus achieving the purpose of solvent separation.

[0007] Because this device recovers and utilizes the latent heat of vaporization of the solvent, and there is no release of latent heat of vaporization from the cooling tower, the boiler steam consumption can be reduced by 85% in the solvent separation production process.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The technical solution adopted by the present invention: A water-soluble distillation and compression separation device includes a reaction vessel, a gas-liquid separator, a low-pressure balance tank, a high-pressure balance tank, a low-pressure steam purification filter, a steam compressor, a heating device, and an electrical control box. The reactor is equipped with a reactor heating layer. The upper part of the reactor is connected to a vapor-liquid separator via a steam pipe. The vapor-liquid separator is equipped with a return pipe connected to the inside of the reactor. The vapor-liquid separator is also connected to a low-pressure balance tank via a pipeline. A low-pressure steam purification filter is connected to the rear of the low-pressure balance tank. The low-pressure steam purification filter is equipped with a low-pressure steam vent valve. The low-pressure steam purification filter is connected to a steam compressor via a compressor inlet valve. The steam compressor is connected to the reactor heating layer via a high-pressure balance tank. The high-pressure balance tank is connected to a heating device.

[0009] The heating device is a steam boiler; a condensate heat recovery device is connected to the bottom of the heating layer of the reactor and then connected to a high-pressure steam vent valve, and a steam trap is also connected below the condensate heat recovery device; an external water supply pipe passes through the condensate heat recovery device and is connected to the steam boiler.

[0010] The working method of an aqueous solvent distillation and compression separation device is as follows: Step 1: Turn on the steam boiler and open the high-pressure steam vent valve to use the steam from the steam boiler to purge the air from the high-pressure balance tank, the heating layer of the reactor, and the connecting pipes. Step 2: Close the high-pressure steam vent valve, heat the extract and water solvent in the reactor to boiling using the steam boiler, open the low-pressure steam vent valve, use the steam of the water solvent to purge the air from the reactor, low-pressure balance tank, gas-liquid separator and pipelines, then close the low-pressure steam vent valve, shut off the steam boiler and close the boiler steam valve. Step 3: Open the compressor inlet valve and start the steam compressor. The solvent vapor enters the steam compressor through the low-pressure steam purification filter. The steam compressor compresses the low-pressure solvent vapor into high-pressure and high-temperature steam. The high-temperature and high-pressure steam enters the heating layer of the reactor through the high-pressure balance tank. While heating the extract and water solvent in the reactor, it condenses into high-temperature condensate. The high-temperature condensate passes through the condensate heat recovery device to form low-temperature condensate and is discharged. Step 4: When the extract in the reactor reaches the required concentration, turn off the steam compressor and close the compressor inlet valve to complete one extraction cycle of the reactor.

[0011] Preferably, the heating device is connected to the low-pressure steam purification filter through pipelines and backwash valves, and its function is to realize the backwashing of the low-pressure steam purification filter. When the extraction cycle of the reactor is completed, the low-pressure steam vent valve and the backwash valve of the steam boiler are opened to flush the low-pressure steam purification filter with steam from the steam boiler and discharge the residual impurities in the low-pressure steam purification filter from the low-pressure steam vent valve.

[0012] Preferably, the condensate heat recovery unit is an exchanger for heat between condensate and clean softened water, wherein the flow rate of condensate is the same as the design flow rate of clean softened water, and the clean softened water enters the steam boiler as boiler makeup water after passing through the condensate heat recovery unit.

[0013] Preferably, the low-pressure balance tank and the high-pressure balance tank are used to buffer and balance the intake pressure and discharge pressure of the compressor, and to prevent drastic changes in the intake pressure and discharge pressure of the compressor during operation.

[0014] The beneficial effects of this invention are: Since there is no release of the latent heat of solvent vaporization, the boiler steam consumption is reduced by 85%. The boiler steam is only consumed in the initial stage of heating the extract and water solvent to the boiling point in the reaction vessel. The energy consumption of the compressor accounts for less than 5% of the latent heat of vaporization. For example, when the compressor's suction temperature is 90℃ and the discharge temperature is 120℃, the vapor enthalpy difference (i.e., the energy consumption of the compressor) is: 2706.3kj / kg - 2660.1kj / kg = 46.2kj / kg, while the latent heat of vaporization of water at 100℃ is 2257.9kj / kg. Therefore, under this condition, the energy consumption of the compressor accounts for only 2% of the latent heat of vaporization (46.2 / 2257.9=2%). Therefore, the energy consumption of this device is 20% of that of the distillation cooling device, and compared with the distillation cooling device, it can reduce energy consumption by 80%. Attached Figure Description

[0015] Figure 1 The diagram shows the structure and working principle of each component of this invention; The components include: 1. Steam trap; 2. High-pressure steam vent valve; 3. Condensate heat recovery unit; 4. Check valve; 5. Reactor heating layer; 6. Reactor; 7. Reactor steam pipe; 8. Vapor-liquid separator; 9. Low-pressure balance tank; 10. Low-pressure steam vent valve; 11. Low-pressure steam purification filter; 12. Backwash valve; 13. Boiler steam valve; 14. Compressor inlet valve; 15. Steam compressor; 16. High-pressure balance tank; 17. Electrical control connection cable; 18. Electrical control box; 19. Steam boiler; 20. Cleaning and softening water pipe. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0017] Example 1: See Figure 1The present invention provides a distillation and compression separation device, including a reaction vessel 6, a gas-liquid separator 8, a low-pressure balance tank 9, a high-pressure balance tank 16, a low-pressure steam purification filter 11, a steam compressor 15, a steam boiler 19, an electrical control box 18, a condensate heat recovery unit 3, and other components.

[0018] A more specific connection method is as follows: The reactor 6 is provided with a reactor heating layer 5. The upper part of the reactor 6 is connected to the vapor-liquid separator 8 through the reactor steam pipe 7. The vapor-liquid separator 8 is provided with a return pipe connected to the reactor. The vapor-liquid separator 8 is also connected to the low-pressure balance tank 9 through a pipeline. The rear side of the low-pressure balance tank 9 is connected to the low-pressure steam purification filter 11 through a one-way valve II 41. The low-pressure steam purification filter 11 is provided with a low-pressure steam vent valve 10. The low-pressure steam purification filter 11 is connected to the steam compressor 15 through the compressor inlet valve 14. The steam compressor 15 is connected to the reactor heating layer 5 through the high-pressure balance tank 16 and the one-way valve III 42. The high-pressure balance tank 16 is connected to the heating device. In this embodiment, the heating device is a steam boiler 19; the bottom of the reactor heating layer 5 is connected to a condensate heat recovery device 3 via a one-way valve I4 and then connected to a high-pressure steam vent valve 2. A steam trap 1 is also connected below the condensate heat recovery device 3. The steam trap 1 only discharges liquid and does not discharge gas.

[0019] The low-pressure balance tank 9 and the high-pressure balance tank 16 are used to buffer and balance the suction pressure and discharge pressure of the steam compressor 15, and to prevent drastic changes in the suction pressure and discharge pressure of the steam compressor 15 during operation.

[0020] An external clean water softening pipe 20 is connected to the steam boiler 19 after being supplemented by heat from the condensate heat recovery unit 3. The flow rate of condensate in the steam trap 1 is the same as the design flow rate of the clean water softening pipe 20. The water in the clean water softening pipe 20 enters the clean steam boiler after passing through the condensate heat recovery unit, and is used as boiler makeup water.

[0021] The steam boiler 19 is connected to the low-pressure steam purification filter 11 via pipelines, boiler steam valve 13 and backwash valve 12.

[0022] The electrical control box 18 is connected to the following components via electrical control connection line 17, and controls the opening and closing of the following components: steam boiler 19, steam compressor 15, compressor inlet valve 14, backwash valve 12, and boiler steam valve 13.

[0023] The outlets of the aforementioned reactor heating layer 5, low-pressure balance tank 9, and high-pressure balance tank 16 are respectively equipped with one-way valve I4, one-way valve II41, and one-way valve III42, the purpose of which is to prevent the reverse entry of steam and air.

[0024] Example 2: The working method of an aqueous solvent distillation and compression separation device is as follows: Step 1: Load the extract and aqueous solution into the reaction vessel 6, turn on the steam boiler 19, open the high-pressure steam vent valve 2, and use the steam from the steam boiler 19 to remove the air from the high-pressure balance tank 16, the heating layer 5 of the reaction vessel, and the connecting pipes. Step 2: Close the high-pressure steam vent valve 2, heat the extract and water solvent in the reaction vessel 6 to boiling using the steam boiler 19, open the low-pressure steam vent valve 10, and use the steam of the water solvent to remove air from the reaction vessel 6, low-pressure balance tank 9, gas-liquid separator 8 and pipelines. Then close the low-pressure steam vent valve 10, close the steam boiler 19, and close the boiler steam valve 13. Step 3: Open the compressor inlet valve 14 and start the steam compressor 15. The solvent vapor enters the steam compressor 15 through the low-pressure steam purification filter 11. The steam compressor 15 compresses the low-pressure solvent vapor into high-pressure and high-temperature steam. The high-temperature and high-pressure steam enters the heating layer 5 of the reaction vessel through the high-pressure balance tank 16. While heating the extract and water solvent in the reaction vessel 6, it condenses into high-temperature condensate. After passing through the condensate heat recovery device 3, the high-temperature condensate forms low-temperature condensate and is discharged, thus realizing the separation of water solvent and extract. During the heating process of the reactor 6, the steam compressor 15 draws in the steam of the water solvent in the reactor 6 to reduce the pressure of the steam in the reactor 6, thereby lowering the boiling point of the water solvent. The steam compressor 15 compresses the drawn-in water vapor into high-temperature and high-pressure steam for heating the reactor 6, causing the solvent in the reactor 6 to boil further. The lower the pressure in the reactor 6, the lower its boiling point, and the lower its relative temperature on the wall of the reactor heating layer 5. This further promotes the condensation of the steam into a high-temperature liquid in the reactor heating layer 5. The high-temperature liquid is converted into a low-temperature liquid by the condensate heat recovery device and discharged from the condensate drain, thus achieving and accelerating the purpose of solvent separation.

[0025] Step 4: When the extract in the reactor reaches the required concentration, turn off the steam compressor and close the compressor inlet valve to complete one extraction cycle of the reactor.

[0026] As a further technical extension, the present invention also has a backwashing function for the low-pressure steam purification filter 11: the steam boiler 19 is connected to the low-pressure steam purification filter 11 through pipelines and backwash valve 12; when the extraction cycle of the reactor 6 is completed, the low-pressure steam vent valve 10 is opened and the backwash valve 12 matched with the steam boiler 19 is opened, and the steam of the steam boiler 19 is used to flush the low-pressure steam purification filter 11, so that the residual impurities in the low-pressure steam purification filter 11 are discharged from the low-pressure steam vent valve 10.

[0027] In the above method, in order to maintain the stable operation of the steam boiler 19, part of the makeup water of the steam boiler 19 enters the condensate heat recovery unit 3 through the clean softened water pipe 20, and then enters the steam boiler 19 after heat exchange and energy absorption to form high temperature water.

Claims

1. A water-solvent distillation and compression separation apparatus, characterized in that: Includes a reaction vessel, gas-liquid separator, low-pressure balance tank, high-pressure balance tank, low-pressure steam purification filter, steam compressor, heating device, and electrical control box; The reactor is equipped with a reactor heating layer. The upper part of the reactor is connected to a vapor-liquid separator via a steam pipe. The vapor-liquid separator is equipped with a return pipe connected to the inside of the reactor. The vapor-liquid separator is also connected to a low-pressure balance tank via a pipeline. A low-pressure steam purification filter is connected to the rear of the low-pressure balance tank. The low-pressure steam purification filter is equipped with a low-pressure steam vent valve. The low-pressure steam purification filter is connected to a steam compressor via a compressor inlet valve. The steam compressor is connected to the reactor heating layer via a high-pressure balance tank. The high-pressure balance tank is connected to a heating device.

2. The water-solvent distillation and compression separation apparatus as described in claim 1, characterized in that: The heating device is a steam boiler; a condensate heat recovery device is connected to the bottom of the heating layer of the reactor and then connected to a high-pressure steam vent valve, and a steam trap is also connected below the condensate heat recovery device; an external water supply pipe passes through the condensate heat recovery device and is connected to the steam boiler.

3. The method of using the water-solvent distillation compression separation device as described in claim 2, characterized in that: Solvent vapor enters the steam compressor through a low-pressure steam purification filter. The steam compressor compresses the low-pressure solvent vapor into high-pressure, high-temperature steam. The high-temperature, high-pressure steam enters the heating layer of the reactor through a high-pressure balance tank, heating the extract and aqueous solvent in the reactor while condensing into high-temperature condensate. The high-temperature condensate passes through a condensate heat recovery unit to achieve the separation of the aqueous solvent and the extract.

4. The method of using the water-solvent distillation compression separation apparatus as described in claim 3, characterized in that: The steam boiler is connected to the low-pressure steam purification filter through pipelines and backwash valves. When the extraction cycle of the reactor is completed, the low-pressure steam vent valve is opened and then the backwash valve is opened to flush the low-pressure steam purification filter with steam from the steam boiler and discharge it.

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