Rectification coupling concentration decolorization device

Abstract

The utility model belongs to the technical field of vitamin C purification devices, and particularly relates to a rectification coupling concentration decolorization device. The rectifying, coupling, concentrating and decolorizing device comprises an atmospheric tower, a falling-film evaporator, an atmospheric tower return tank and a gas-liquid separator, a methanol steam pipe is arranged on the atmospheric tower, a coupling pipe is connected onto the methanol steam pipe, the falling-film evaporator is provided with a shell, the coupling pipe is connected onto the shell, and the gas-liquid separator is connected onto the shell. A decolorizing liquid feeding pipe is arranged on the falling film evaporator body, the falling film evaporator body is connected with the gas-liquid separator, the bottom of the falling film evaporator body is connected with the circulating pump, the circulating pump is connected with the top of the falling film evaporator body, the gas-liquid separator is connected with the circulating pump, a discharging pump is further arranged at the bottom of the falling film evaporator body, and the gas-liquid separator is connected with the discharging pump. And the falling film evaporator body is connected with the atmospheric tower return tank. The utility model provides a rectification coupling concentration decoloration device which solves the problems of heat loss and water waste of an atmospheric tower and a decoloration device, saves energy and reduces consumption.

Description

Technical Field

[0001] The utility model belongs to the technical field of vitamin C purification devices, and in particular relates to a rectification coupled concentration and decolorization device. Background Art

[0002] At present, the synthesis process of raw material vitamin C mainly uses sodium vitamin C as raw material, and produces vitamin C through acidification, separation, desalination, recovery, refining and purification. The refining and purification adopts the existing single-effect tower, double-effect tower atmospheric pressure tower, and triple-effect tower atmospheric pressure tower. The methanol vapor at 65°C at the top of the tower is condensed by a circulating water heat exchanger. The problems are as follows: (1) Large heat loss: The calorific value of methanol vapor generated per hour is 16 million kcal, which is directly condensed by circulating water, resulting in heat waste. (2) Waste of circulating water: including the operation of high-power circulating water pumps and cooling tower fans consumes electricity, and the volatilization of circulating water requires a large amount of tap water to be supplemented. (3) Waste of ice brine and methanol caused by insufficient cooling capacity in summer.

[0003] In the existing decolorization process, the decolorization liquid external circulation is mainly used, which requires the decolorization liquid with a content of 17% to be concentrated into a concentrated crystallization liquid with a content of 80% in a 4-hour cycle. The following problems exist: (1) The steam consumption is large: 30 tons of steam are required per hour; (2) The long steaming cycle affects the quality; (3) The circulating pump and vacuum pump used in the forced external circulation consume a lot of power; (4) In summer, due to the high temperature of the circulating water, the existing equipment cannot meet the production demand and leads to methanol volatilization loss. Utility Model Content

[0004] The technical problem to be solved by the utility model is to overcome the above-mentioned defects in the prior art, provide a distillation-coupled concentration and decolorization device, improve the problems of heat loss and water waste in the atmospheric pressure tower and the decolorization device, and save energy and reduce consumption.

[0005] The distillation coupling concentration and decolorization device described in the utility model comprises an atmospheric tower, a falling film evaporator, an atmospheric tower reflux tank, and a gas-liquid separator. The atmospheric tower is provided with a methanol steam pipe, the methanol steam pipe is connected with a coupling pipe, the falling film evaporator is provided with a shell, the coupling pipe is connected to the shell, the falling film evaporator body is provided with a decolorizing liquid feed pipe, the falling film evaporator body is connected to the gas-liquid separator, the bottom of the falling film evaporator body is connected to a circulation pump, the circulation pump is connected to the top of the falling film evaporator body, the gas-liquid separator is connected to the circulation pump, the bottom of the falling film evaporator body is also provided with a discharge pump, and the falling film evaporator body is connected to the atmospheric tower reflux tank. The atmospheric tower is a common distillation tower, and its main function is to distill the materials in the tower. It is an existing commercially available device, and its internal structure is no longer discussed in detail. The falling film evaporator is an existing device, and its internal structure is provided with a secondary distributor, that is, an existing two-layer parallel liquid distributor, and a heating tube is also provided inside, also called a falling film tube. Therefore, its internal structure is also an existing device, so its internal structure is no longer discussed. The outside of its body is provided with an outer shell, which mainly serves the function of heating and heat preservation.

[0006] Preferably, the methanol steam pipe is connected to the primary condenser, the primary condenser is connected to the secondary condenser, the secondary condenser is connected to the atmospheric tower reflux tank, and the atmospheric tower reflux tank is connected to the atmospheric tower via a reflux pump.

[0007] Preferably, the falling film evaporator body is connected to a secondary condenser.

[0008] Preferably, the primary condenser is connected to the reflux tank of the atmospheric tower.

[0009] Preferably, the top of the gas-liquid separator is connected to a condensing device, the condensing device is connected to a methanol storage tank, and the methanol storage tank is connected to a vacuum device. The condensing device is a common condensing device, and its main function is to cool the material. It can be a condenser or other equipment for condensation. They are all existing devices, so no further limitation is made on their internal structure.

[0010] Further preferably, the methanol storage tank is provided with a methanol outlet pipe with water.

[0011] Preferably, a methanol extraction pipe is provided on the outlet pipe of the reflux pump.

[0012] Preferably, the pipeline connecting the falling film evaporator body and the atmospheric tower reflux tank is a methanol condensate pipe.

[0013] The utility model discloses a rectification coupled concentration and decolorization device, wherein the steam after distillation at the top of the atmospheric tower enters a primary condenser and a secondary condenser for condensation, and the condensate after condensation enters a reflux tank of the atmospheric tower, a coupling pipe is connected to the methanol steam pipe at the top of the atmospheric tower, the coupling pipe is connected to the body of the falling film evaporator, and low-content decolorization liquid is continuously fed into the body of the falling film evaporator through a decolorization liquid feed pipe, a secondary distributor inside the falling film evaporator ensures that the decolorization liquid enters the falling film tube array uniformly, the shell side of the outer shell of the falling film evaporator enters the methanol steam of the atmospheric tower, the tube side inside the falling film evaporator is the decolorization liquid, a gas-liquid separator is connected in parallel below the tube side, the bottoms of the falling film evaporator and the gas-liquid separator are both connected to a circulating pump, and a discharging pump is arranged at the bottom of the falling film evaporator, the circulating pump with a large flow rate realizes the material flow rate entering the falling film, ensures the evaporation rate, and the discharging pump realizes continuous extraction of the decolorization liquid with increased concentration by calculating the height and the outlet. The methanol condensed in the shell side of the falling film evaporator enters the reflux tank of the atmospheric tower. The falling film evaporator body is vacuumed to achieve a steam temperature below 50°C, and the methanol-containing gas is absorbed to achieve methanol recovery and safe discharge. The 65°C methanol vapor heats the decolorized liquid below 50°C, increasing the decolorized liquid content from 17% to about 30%.

[0014] Compared with the prior art, the utility model has the following beneficial effects:

[0015] (1) The distillation-coupled concentration and decolorization device of the utility model significantly reduces the amount of steam required for concentrating the decolorized liquid by adding a falling film evaporator and a gas-liquid separator.

[0016] (2) The distillation-coupled concentration and decolorization device of the utility model reduces the concentration external circulation steaming cycle from 4 hours to less than 2 hours by adding a falling film evaporator and a gas-liquid separator, reduces the use of the concentration pot by half, and reduces the use of the power circulation water by half.

[0017] (3) The distillation-coupled concentration and decolorization device of the utility model reduces the temperature and cycle of crude vitamin C steaming and improves the quality of crude vitamin C by adding a falling film evaporator and a gas-liquid separator. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the distillation-coupled concentration and decolorization device of the utility model.

[0019] In the figure: 1. atmospheric tower; 2. falling film evaporator; 3. primary condenser; 4. secondary condenser; 5. methanol storage tank; 6. condensing device; 7. atmospheric tower reflux tank; 8. gas-liquid separator; 9. methanol steam pipe; 10. coupling pipe; 11. decolorizing liquid feed pipe; 12. methanol condensate pipe; 13. discharge pump; 14. circulation pump; 15. reflux pump; 16. methanol extraction pipe; 17. vacuum device; 18. methanol outlet pipe with water; 19. outer shell. DETAILED DESCRIPTION

[0020] The utility model is further described below in conjunction with specific embodiments.

[0021] In the present invention, the terms "connected" and "connected" should be understood in a broad sense in the chemical industry. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] In the present utility model, the falling film evaporator, condensation device, condenser, etc. are all existing commercially available devices, and the internal structure of the devices is mature and is prior art. Those skilled in the art can make a clear judgment, so their internal structures are no longer discussed in detail. In addition, the "inlet" and "outlet" that appear in the description are conventional settings in the structure, and are conventional structures that are well known and operable by those skilled in the art, so they are no longer specifically marked in the structure of the present utility model.

[0023] like Figure 1 As shown, the rectification coupled concentration and decolorization device comprises an atmospheric tower 1, a falling film evaporator 2, an atmospheric tower reflux tank 7, and a gas-liquid separator 8. The atmospheric tower 1 is provided with a methanol steam pipe 9, and the methanol steam pipe 9 is connected with a coupling pipe 10. The falling film evaporator 2 is provided with a shell 19, and the coupling pipe 10 is connected to the shell 19. The falling film evaporator 2 body is provided with a decolorizing liquid feed pipe 11. The falling film evaporator 2 body is connected to the gas-liquid separator 8. The bottom of the falling film evaporator 2 body is connected to a circulating pump 14, and the circulating pump 14 is connected to the top of the falling film evaporator 2 body. The gas-liquid separator 8 is connected to the circulating pump 14. The bottom of the falling film evaporator 2 body is also provided with a discharge pump 13, and the falling film evaporator 2 body is connected to the atmospheric tower reflux tank 7. The atmospheric tower 1 is a common rectification tower, and its main function is to distill the materials in the tower. It is an existing commercially available device, and its internal structure is not discussed in detail. The falling film evaporator 2 is an existing device, and its internal structure is provided with a secondary distributor, that is, an existing two-layer parallel liquid distributor, and a heating tube is also provided inside, also called a falling film tube. Therefore, its internal structure is also an existing device, so its internal structure is no longer discussed. The outer shell 19 is provided on the outside of its body, and its main function is heating and heat preservation.

[0024] The methanol steam pipe 9 is connected to the primary condenser 3, the primary condenser 3 is connected to the secondary condenser 4, the secondary condenser 4 is connected to the atmospheric tower reflux tank 7, and the atmospheric tower reflux tank 7 is connected to the atmospheric tower 1 through a reflux pump 15.

[0025] The falling film evaporator 2 body is connected to the secondary condenser 4 .

[0026] The primary condenser 3 is connected to the atmospheric tower reflux tank 7 .

[0027] The top of the gas-liquid separator 8 is connected to the condensing device 6, the condensing device 6 is connected to the methanol storage tank 5, and the methanol storage tank 5 is connected to the vacuum device 17. The condensing device 6 is a common condensing device, and its main function is to cool the material. It can be a condenser or other equipment for condensation. They are all existing devices, so no further limitation is made on their internal structure.

[0028] The methanol storage tank 5 is provided with a methanol outlet pipe 18 with water.

[0029] The outlet pipe of the reflux pump 15 is provided with a methanol extraction pipe 16 .

[0030] The pipeline connecting the falling film evaporator 2 body and the atmospheric tower reflux tank 7 is a methanol condensate pipe 12.

[0031] The distillation coupled concentration and decolorization device described in the utility model is that the steam after distillation at the top of the atmospheric tower 1 enters the primary condenser 3 and the secondary condenser 4 for condensation, and the condensed condensate enters the atmospheric tower reflux tank 7, and the methanol steam pipe 9 at the top of the atmospheric tower 1 is connected with a coupling pipe 10, and the coupling pipe 10 is connected to the body of the falling film evaporator 2, and the low-content decolorized liquid is continuously fed into the body of the falling film evaporator 2 through the decolorized liquid feed pipe 11, and the secondary distributor inside the falling film evaporator 2 ensures that the decolorized liquid is evenly fed into the falling film evaporator 2. Enter the falling film tube array, the shell side of the falling film evaporator 2 enters the methanol vapor of the atmospheric tower 1, the internal tube side of the falling film evaporator 2 is the decolorant, the gas-liquid separator 8 is connected in parallel below the tube side, the bottom of the falling film evaporator 2 and the gas-liquid separator 8 are connected to the circulating pump 14, and a discharge pump 13 is arranged at the bottom of the falling film evaporator 2, the large flow circulation pump 14 realizes the material flow entering the falling film, ensures the evaporation rate, and the discharge pump 13 realizes continuous extraction of the decolorant with increased concentration by calculating the height and the outlet. The methanol condensed in the shell side of the falling film evaporator 2 enters the atmospheric tower reflux tank 7, the body of the falling film evaporator 2 is vacuumed to achieve the steam material temperature below 50°C, and the methanol-containing gas is also absorbed, so as to achieve methanol recovery and safe discharge, and the 65°C methanol vapor heats the decolorant below 50°C, and the decolorant content is increased from 17% to about 30%.

[0032] The rectification coupled concentration and decolorization device of the utility model is applied to the synthesis process of raw material medicine vitamin C.

[0033] Of course, the above contents are only preferred embodiments of the present invention and cannot be considered to limit the scope of the embodiments of the present invention. The present invention is not limited to the above examples, and any equivalent changes and improvements made by ordinary technicians in the technical field within the essential scope of the present invention shall fall within the scope of the patent coverage of the present invention.

Claims

1. A distillation coupled concentration and decolorization device, characterized in that: The invention comprises an atmospheric tower (1), a falling film evaporator (2), an atmospheric tower reflux tank (7), and a gas-liquid separator (8); the atmospheric tower (1) is provided with a methanol steam pipe (9), the methanol steam pipe (9) is connected with a coupling pipe (10), the falling film evaporator (2) is provided with a shell (19), the coupling pipe (10) is connected to the shell (19), the falling film evaporator (2) body is provided with a decolorizing liquid feed pipe (11), the The falling film evaporator (2) body is connected to a gas-liquid separator (8), the bottom of the falling film evaporator (2) body is connected to a circulation pump (14), the circulation pump (14) is connected to the top of the falling film evaporator (2) body, the gas-liquid separator (8) is connected to the circulation pump (14), a discharge pump (13) is also provided at the bottom of the falling film evaporator (2) body, and the falling film evaporator (2) body is connected to a reflux tank (7) of an atmospheric tower.

2. The distillation-coupled concentration-decolorization device according to claim 1, characterized in that: The methanol steam pipe (9) is connected to the primary condenser (3), the primary condenser (3) is connected to the secondary condenser (4), the secondary condenser (4) is connected to the atmospheric tower reflux tank (7), and the atmospheric tower reflux tank (7) is connected to the atmospheric tower (1) via a reflux pump (15).

3. The distillation-coupled concentration-decolorization device according to claim 2, characterized in that: The falling film evaporator (2) body is connected to the secondary condenser (4).

4. The distillation-coupled concentration-decolorization device according to claim 2, characterized in that: The primary condenser (3) is connected to the atmospheric tower reflux tank (7).

5. The distillation-coupled concentration-decolorization device according to claim 1, characterized in that: The top of the gas-liquid separator (8) is connected to the condensing device (6), the condensing device (6) is connected to the methanol storage tank (5), and the methanol storage tank (5) is connected to the vacuum device (17).

6. The distillation-coupled concentration-decolorization device according to claim 5, characterized in that: The methanol storage tank (5) is provided with a methanol outlet pipe (18) containing water.

7. The distillation-coupled concentration-decolorization device according to claim 2, characterized in that: The outlet pipe of the reflux pump (15) is provided with a methanol extraction pipe (16).

8. The distillation-coupled concentration-decolorization device according to claim 1, characterized in that: The pipeline connecting the falling film evaporator (2) body and the atmospheric tower reflux tank (7) is a methanol condensate pipe (12).

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