A device for ammonium sulfate and sodium sulfate reaction cooling crystallization

Abstract

This invention discloses a cooling crystallization device for the reaction of ammonium sulfate and sodium sulfate, including a crystallizer for crystallizing the reaction between materials; an external cooler located on one side of the crystallizer for cooling the materials; and a feed circulation pump. This invention allows the sodium sulfate slurry and sodium bicarbonate centrifugal mother liquor to directly mix and react inside the lower insertion pipe and downcomer, thus entering the bottom of the outer cylinder. This effectively prevents high salt content in the crystallizer overflow due to severe boiling during the reaction. The inverted cone design increases the liquid flow rate to some extent, preventing crystal deposition at the bottom of the crystallizer and causing blockage. A water tank is located outside the sodium sulfate slurry feed pipe, and an electric heating element heats the water inside the tank. The heated water surrounds the outside of the sodium sulfate slurry feed pipe, further heating the material during feeding and effectively preventing or mitigating pipe blockage caused by material cooling.

Description

Technical Field

[0001] This utility model relates to the technical field of crystallization, specifically to a device for cooling and crystallizing the reaction of ammonium sulfate and sodium sulfate. Background Technology

[0002] Traditional sodium bicarbonate production uses the Hou's process, employing sodium chloride and ammonium bicarbonate in a double decomposition reaction to produce ammonium bicarbonate, with ammonium chloride as a byproduct. While this process is simple, it is currently uneconomical, as the byproduct ammonium chloride has low economic value. Most chemical companies, especially those in the lithium-ion battery and fine chemical industries, have large quantities of sodium sulfate as a byproduct. Sodium sulfate can be used instead of sodium chloride as a raw material to obtain sodium bicarbonate, with ammonium sulfate as a byproduct.

[0003] In this process, sodium bicarbonate and ammonium sulfate mother liquor and sodium sulfate slurry need to enter the recrystallization unit for reaction and cooling to precipitate sodium ammonium sulfate double salt (molecular formula (NH4)2SO4·Na2SO4·4H2O), and sodium ammonium sulfate, sodium bicarbonate and crystallization mother liquor are separated in the cooling crystallization unit.

[0004] However, the crystallization devices used in the existing process still have some problems: severe boiling of the liquid surface in the crystallizer leads to a high salt content in the overflow liquid, the bottom of the crystallizer is prone to blockage, causing the liquid at the bottom of the crystallizer to back up, the sodium sulfate slurry feed pipe is prone to blockage, the feed circulation pump vibrates greatly at the top of the crystallizer, and the external cooler needs to be cleaned frequently. To address these issues, we have proposed a reaction cooling crystallization device using ammonium sulfate and sodium sulfate to solve the above problems. Utility Model Content

[0005] The purpose of this invention is to provide a device for the reaction and cooling crystallization of ammonium sulfate and sodium sulfate to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a device for the reaction and cooling crystallization of ammonium sulfate and sodium sulfate, comprising...

[0007] A crystallizer is used to crystallize the reaction between materials.

[0008] An external cooler is located on one side of the crystallizer and is used to cool the material.

[0009] A liquid circulation pump is located between the crystallizer and the external cooler. A long pipe and a short pipe are fixedly installed on the liquid circulation pump. The other end of the long pipe is fixedly installed on the crystallizer, and the other end of the short pipe is fixedly installed on the external cooler.

[0010] A refrigerant circulation pump is installed on the outside of the external cooler, and the refrigerant circulation pump is connected to the external cooler;

[0011] The crystallizer and the external cooler are connected by a connecting pipe.

[0012] As a further preferred embodiment of this technical solution, the crystallizer includes an outer cylinder, a collection tank is provided on the outer side of the outer cylinder, a sodium bicarbonate centrifugal mother liquor inlet is fixedly provided on the top of the collection tank, a lower insertion pipe is provided inside the outer cylinder, a downcomer is fixedly connected to the top of the lower insertion pipe, the other end of the downcomer passes through the outer cylinder and is connected to the collection tank, a sodium sulfate slurry feed pipe is provided at the top of the crystallizer, the bottom end of the sodium sulfate slurry feed pipe is fixedly connected to the downcomer, a circulating liquid outlet is fixedly installed at the top of the crystallizer, the circulating liquid outlet is connected to a long pipe, a water tank is fixedly installed on the outer side of the sodium sulfate slurry feed pipe, an electric heating tube is fixedly provided inside the water tank, the electric heating tube is annularly wrapped around the outer side of the sodium sulfate slurry feed pipe, a water inlet pipe is fixedly installed on the water tank, the ends of the electric heating tube and the water inlet pipe both pass through the inside of the outer cylinder, and the other end of the water inlet pipe is connected to an external water pump.

[0013] As a further preferred embodiment of this technical solution, an exhaust pipe is fixedly installed on the water tank, and the end of the exhaust pipe passes through the crystallizer and is located on the outside of the sodium sulfate slurry feed pipe.

[0014] As a further preferred embodiment of this technical solution, the exhaust pipes are evenly spaced on the water tank, and the end of the exhaust pipe passing through the crystallizer is inclined.

[0015] As a further preferred embodiment of this technical solution, the liquid collection tank is provided in two sets, which are symmetrically distributed on the outer side of the outer cylinder, and both sets of liquid collection tanks are connected to the downcomer.

[0016] As a further preferred embodiment of this technical solution, an inverted cone is fixedly installed inside the outer cylinder, the inverted cone being located below the bottom end of the lower insertion tube, and a discharge port is fixedly installed on the outer side of the outer cylinder, the discharge ports being symmetrically distributed on the outer side of the outer cylinder.

[0017] As a further preferred embodiment of this technical solution, the external cooler includes a housing, an upper tube box is fixedly installed on the top of the housing, a lower tube box is fixedly installed on the bottom of the housing, the top of the upper tube box is fixedly connected to a connecting pipe, and the other end of the connecting pipe is fixedly installed on the outside of a long pipe.

[0018] This invention provides a cooling crystallization apparatus for the reaction of ammonium sulfate and sodium sulfate, which has the following advantages:

[0019] This invention features a lower insertion pipe and a downcomer inside the outer cylinder. The downcomer is arc-shaped inside the outer cylinder, and the bottom of the sodium sulfate slurry feed pipe is connected to the downcomer. The sodium sulfate slurry and sodium bicarbonate centrifugal mother liquor can directly mix and react inside the lower insertion pipe and downcomer before entering the bottom of the outer cylinder. This effectively prevents high salt content in the crystallizer overflow due to severe boiling during the reaction. The inverted cone shape increases the liquid flow rate to a certain extent, preventing crystals from depositing at the bottom of the crystallizer and causing blockage. A water tank is located outside the sodium sulfate slurry feed pipe, and an electric heating element heats the water inside the tank. The heated water surrounds the outside of the sodium sulfate slurry feed pipe, which heats the material being fed, effectively preventing or mitigating pipe blockage caused by material cooling.

[0020] This invention uses a small cone angle for the upper and lower tube boxes, which allows for more uniform liquid distribution within the external cooler, reducing turbulence and short-circuit flow, thereby reducing the frequency of cleaning the external cooler. Additionally, the liquid circulation pump is positioned below the crystallizer, which avoids significant vibration to the crystallizer. Attached Figure Description

[0021] Figure 1 This is a front view schematic diagram of the structure of this utility model;

[0022] Figure 2 This is a front view sectional diagram of the outer cylinder of this utility model;

[0023] Figure 3 This utility model Figure 2 Enlarged structural diagram of A in the middle;

[0024] Figure 4 This is a front view schematic diagram of the upper and lower pipe boxes of this utility model.

[0025] In the diagram: 1. Crystallizer; 2. External cooler; 3. Feed circulation pump; 4. Refrigerant circulation pump; 5. Outer cylinder; 6. Collection tank; 7. Sodium bicarbonate centrifugal mother liquor inlet; 8. Lower insertion pipe; 9. Downcomer; 10. Sodium sulfate slurry feed pipe; 11. Circulating liquid outlet; 12. Inverted cone; 13. Discharge port; 14. Water tank; 15. Electric heating element; 16. Water inlet pipe; 17. Exhaust pipe; 18. Shell; 19. Upper pipe box; 20. Lower pipe box. Detailed Implementation

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0027] This utility model provides a technical solution: such as Figure 1 , Figure 2 and Figure 3As shown in this embodiment, an ammonium sulfate and sodium sulfate reaction cooling crystallization device includes a crystallizer 1 for crystallizing the reaction between materials; an external cooler 2, located on one side of the crystallizer 1 for cooling the materials; a liquid circulation pump 3, located between the crystallizer 1 and the external cooler 2, with a long pipe and a short pipe fixedly mounted on the pump 3, the other end of the long pipe fixedly mounted on the crystallizer 1 and the other end of the short pipe fixedly mounted on the external cooler 2; a refrigerant circulation pump 4, located on the outside of the external cooler 2, connected to the external cooler 2; the crystallizer 1 and the external cooler 2 are connected by a connecting pipe; the crystallizer 1 includes an outer cylinder 5. A collection tank 6 is provided on the outside of the crystallizer 1. A sodium bicarbonate centrifugal mother liquor inlet 7 is fixedly installed on the top of the collection tank 6. A lower insertion pipe 8 is provided inside the outer cylinder 5. A downcomer 9 is fixedly connected to the top of the lower insertion pipe 8. The other end of the downcomer 9 passes through the outer cylinder 5 and is connected to the collection tank 6. A sodium sulfate slurry feed pipe 10 is provided on the top of the crystallizer 1. The bottom end of the sodium sulfate slurry feed pipe 10 is fixedly connected to the downcomer 9. A circulating liquid outlet 11 is fixedly installed on the top of the crystallizer 1. The circulating liquid outlet 11 is connected to a long pipe. A water tank 14 is fixedly installed on the outside of the sodium sulfate slurry feed pipe 10. An electric heating tube 15 is fixedly installed inside the water tank 14. The electric heating tube 15 is arranged in a ring around the sodium sulfate slurry. On the outside of the feed pipe 10, a water inlet pipe 16 is fixedly installed on the water tank 14. The ends of the electric heating pipe 15 and the water inlet pipe 16 both pass through the interior of the outer cylinder 5. The other end of the water inlet pipe 16 is connected to an external water pump. A lower insertion pipe 8 and a downcomer 9 are provided inside the outer cylinder 5. The part of the downcomer 9 inside the outer cylinder 5 is arc-shaped. The bottom end of the sodium sulfate slurry feed pipe 10 is connected to the downcomer 9. The sodium sulfate slurry and sodium bicarbonate centrifugal mother liquor can directly mix and react inside the lower insertion pipe 8 and the downcomer 9, thus entering the bottom of the outer cylinder 5. This effectively prevents the high salt content in the overflow liquid of the crystallizer 1 due to severe boiling during the reaction. The inverted cone 12 also increases the liquid flow rate to a certain extent and avoids crystallization. The material deposits at the bottom of the crystallizer 1, causing blockage. A water tank 14 is located outside the sodium sulfate slurry feed pipe 10. An electric heating element 15 heats the water inside the water tank 14. The heated water surrounds the outside of the sodium sulfate slurry feed pipe 10, effectively heating the material during feeding and preventing or mitigating pipe blockage caused by material cooling. An exhaust pipe 17 is fixedly installed on the water tank 14. The end of the exhaust pipe 17 passes through the crystallizer 1 and is located outside the sodium sulfate slurry feed pipe 10. The exhaust pipes 17 are evenly spaced on the water tank 14, and the end of the exhaust pipe 17 passing through the crystallizer 1 is inclined. Through the exhaust pipes 17, the water inside the water tank 14 is heated by the electric heating element 15.A large amount of hot steam will be generated and flow upward from inside the exhaust pipe 17, and sprayed onto the outside of the sodium sulfate slurry feed pipe 10 from the bend of the exhaust pipe 17, thereby preheating the external part of the sodium sulfate slurry feed pipe 10. Two sets of collection tanks 6 are provided, symmetrically distributed on the outside of the outer cylinder 5. Both sets of collection tanks 6 are connected to the downcomer 9. The collection tanks 6 enable further pre-storage of the mother liquor. An inverted cone is fixedly installed inside the outer cylinder 5. 12. The inverted cone 12 is located below the bottom end of the lower insertion tube 8. A discharge port 13 is fixedly installed on the outer side of the outer cylinder 5. The discharge ports 13 are symmetrically distributed on the outer side of the outer cylinder 5. The inverted cone 12 acts as a backflushing mechanism for the material being fed, increasing the liquid flow rate to a certain extent and preventing crystals from depositing at the bottom of the crystallizer 1 and causing blockage. Furthermore, the discharge ports 13 can be selected in one or more groups depending on the operating conditions, reducing dead zones within the equipment and lowering the risk of blockage at the bottom of the crystallizer 1.

[0028] like Figure 4 As shown, the external cooler 2 includes a housing 18, an upper tube box 19 is fixedly installed on the top of the housing 18, and a lower tube box 20 is fixedly installed on the bottom of the housing 18. The top end of the upper tube box 19 is fixedly connected to a connecting pipe, and the other end of the connecting pipe is fixedly installed on the outside of a long pipe. By setting the upper tube box 19 and the lower tube box 20 into a small cone angle, the liquid can be distributed more evenly in the external cooler 2, reducing turbulence and short-circuit flow, thereby reducing the cleaning frequency of the external cooler 2.

[0029] This invention provides a device for cooling and crystallizing the reaction of ammonium sulfate and sodium sulfate, the specific working principle of which is as follows:

[0030] In operation, the outer cylinder 5 is equipped with a lower insertion pipe 8 and a downcomer 9. The portion of the downcomer 9 inside the outer cylinder 5 is arc-shaped. The bottom end of the sodium sulfate slurry inlet pipe 10 is connected to the downcomer 9. The sodium sulfate slurry and sodium bicarbonate centrifugal mother liquor can directly mix and react inside the lower insertion pipe 8 and the downcomer 9, thus entering the bottom of the outer cylinder 5. This effectively prevents high salt content in the overflow liquid of the crystallizer 1 due to severe boiling during the reaction. Furthermore, the inverted cone 12 increases the liquid flow rate to a certain extent, preventing crystals from depositing at the bottom of the crystallizer 1 and causing blockage. A water tank 14 is installed on the outside of the sodium slurry feed pipe 10. An electric heating tube 15 can heat the water inside the water tank 14. The heated water wraps around the outside of the sodium sulfate slurry feed pipe 10, which can heat the material being fed, effectively avoiding or mitigating pipe blockage caused by material cooling. The upper pipe box 19 and the lower pipe box 20 are designed with a small cone angle, which can make the liquid more evenly distributed in the external cooler 2, reduce turbulence and short-circuit flow, thereby reducing the cleaning frequency of the external cooler 2. The liquid circulation pump 3 is located below the crystallizer 1, which can avoid large vibrations to the crystallizer 1.

[0031] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A device for cooling and crystallizing the reaction of ammonium sulfate and sodium sulfate, characterized in that: include Crystallizer (1) is used to crystallize the reaction between materials; An external cooler (2) is located on one side of the crystallizer (1) and is used to cool the material. A liquid circulation pump (3) is set in the middle of the crystallizer (1) and the external cooler (2). A long pipe and a short pipe are fixedly installed on the liquid circulation pump (3). The other end of the long pipe is fixedly installed on the crystallizer (1), and the other end of the short pipe is fixedly installed on the external cooler (2). A refrigerant circulation pump (4) is installed on the outside of the external cooler (2), and the refrigerant circulation pump (4) is connected to the external cooler (2); The crystallizer (1) and the external cooler (2) are connected by a connecting pipe.

2. The ammonium sulfate and sodium sulfate reaction cooling crystallization apparatus according to claim 1, characterized in that: The crystallizer (1) includes an outer cylinder (5), a collection tank (6) is provided on the outside of the outer cylinder (5), a sodium bicarbonate centrifugal mother liquor inlet (7) is fixedly provided on the top of the collection tank (6), a lower insertion pipe (8) is provided inside the outer cylinder (5), a downcomer (9) is fixedly connected to the top of the lower insertion pipe (8), and the other end of the downcomer (9) passes through the outer cylinder (5) and is connected to the collection tank (6). A sodium sulfate slurry feed pipe (10) is provided at the top of the crystallizer (1), and the bottom end of the sodium sulfate slurry feed pipe (10) is fixedly connected to the downcomer (9). A circulating liquid outlet (11) is fixedly installed on the top of the device (1). The circulating liquid outlet (11) is connected to a long pipe. A water tank (14) is fixedly installed on the outside of the sodium sulfate slurry feed pipe (10). An electric heating tube (15) is fixedly installed inside the water tank (14). The electric heating tube (15) is arranged in a ring around the outside of the sodium sulfate slurry feed pipe (10). A water inlet pipe (16) is fixedly installed on the water tank (14). The ends of the electric heating tube (15) and the water inlet pipe (16) both pass through the inside of the outer cylinder (5). The other end of the water inlet pipe (16) is connected to an external water pump.

3. The ammonium sulfate and sodium sulfate reaction cooling crystallization apparatus according to claim 2, characterized in that: An exhaust pipe (17) is fixedly installed on the water tank (14), and the end of the exhaust pipe (17) passes through the crystallizer (1) and is located on the outside of the sodium sulfate slurry feed pipe (10).

4. The ammonium sulfate and sodium sulfate reaction cooling crystallization apparatus according to claim 3, characterized in that: The exhaust pipes (17) are evenly spaced on the water tank (14), and the end of the exhaust pipes (17) that passes through the crystallizer (1) is inclined.

5. The ammonium sulfate and sodium sulfate reaction cooling crystallization apparatus according to claim 2, characterized in that: The liquid collection tank (6) is provided in two sets, and the two sets of liquid collection tanks (6) are symmetrically distributed on the outside of the outer cylinder (5). Both sets of liquid collection tanks (6) are connected to the downcomer (9).

6. The ammonium sulfate and sodium sulfate reaction cooling crystallization apparatus according to claim 2, characterized in that: An inverted cone (12) is fixedly installed inside the outer cylinder (5). The inverted cone (12) is located below the bottom end of the lower insertion tube (8). A discharge port (13) is fixedly installed on the outer side of the outer cylinder (5). The discharge ports (13) are symmetrically distributed on the outer side of the outer cylinder (5).

7. The ammonium sulfate and sodium sulfate reaction cooling crystallization apparatus according to claim 1, characterized in that: The external cooler (2) includes a housing (18), an upper pipe box (19) is fixedly installed on the top of the housing (18), a lower pipe box (20) is fixedly installed on the bottom of the housing (18), the top of the upper pipe box (19) is fixedly connected to a connecting pipe, and the other end of the connecting pipe is fixedly installed on the outside of a long pipe.

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