A cooling device for precipitation of phenylhydrazine hydrochloride mother liquor

Abstract

This utility model discloses a cooling device for precipitation of phenylhydrazine hydrochloride mother liquor, comprising a refrigeration compressor, an oil separator fixedly connected to the output end of the refrigeration compressor, an evaporative condenser fixedly connected to the main outlet of the oil separator, an auxiliary ammonia storage tank fixedly connected to the outlet of the evaporative condenser via a first pipeline, an ammonia tank fixedly connected to the outlet of the auxiliary ammonia storage tank via a second pipeline, a shut-off valve installed at the connection between the ammonia tank and the second pipeline, and a thin-film evaporator fixedly connected to the outlet of the ammonia tank via a third pipeline. The main outlet of the thin-film evaporator is fixedly connected to a brine tank. Through the above structure, a buffer system is formed by the interlocking of the ammonia tank, the auxiliary ammonia storage tank, and the double shut-off valves, which can quickly isolate the ammonia source in case of emergency shutdown. In addition, the use of a closed-loop system with a low-temperature brine medium can effectively reduce energy consumption, thereby preventing the waste of cooling capacity caused by intermittent production.

Description

Technical Field

[0001] This utility model relates to the technical field of cooling devices, and in particular to a cooling device for precipitation of phenylhydrazine hydrochloride mother liquor. Background Technology

[0002] In the preparation of phenylhydrazine hydrochloride, the cooling device usually refers to the equipment used to separate and process the mother liquor precipitate. By effectively separating the precipitate and the mother liquor, and with the help of cooling treatment, it is easy to improve the yield and purity of the product. The cooling device plays a key role in production and can provide support for subsequent processes. For example, a new type of cold energy cooling device is disclosed in Chinese patent application number CN202122693927.6. It is coiled on the outside of the inner cylinder, and the coiling direction of adjacent coils is opposite, which increases the disturbance of the cold medium between the coils and improves the cooling efficiency. However, when the machine is stopped, the residual cold medium in the coil cannot be effectively utilized. The system needs to be re-pre-cooled when restarted, which consumes extra energy and thus leads to the waste of cold energy. Utility Model Content

[0003] The purpose of this invention is to at least solve one of the technical problems existing in the prior art, and to provide a cooling device for precipitation of phenylhydrazine hydrochloride mother liquor. The use of a wound evaporative condenser can improve heat exchange efficiency. At the same time, multiple evaporative condensers are connected in parallel to realize automatic diversion of refrigerant vapor. A buffer system is formed by interlocking an ammonia tank, an auxiliary ammonia storage tank and a double shut-off valve, which can quickly isolate the ammonia source in case of emergency shutdown. In addition, the use of a closed circulation system with low temperature brine medium can effectively reduce energy consumption, thereby preventing the waste of cold energy caused by intermittent production.

[0004] This utility model also provides a cooling device for precipitation of phenylhydrazine hydrochloride mother liquor, comprising: a refrigeration compressor, an oil separator fixedly connected to the output end of the refrigeration compressor, an evaporative condenser fixedly connected to the main outlet of the oil separator, an auxiliary ammonia storage tank fixedly connected to the outlet of the evaporative condenser via a first pipeline, an ammonia storage tank fixedly connected to the outlet of the auxiliary ammonia storage tank via a second pipeline, a shut-off valve provided at the connection between the ammonia storage tank and the second pipeline, and a thin-film evaporator fixedly connected to the outlet of the ammonia storage tank via a third pipeline; the main outlet of the thin-film evaporator... A brine tank is fixedly connected to the outlet. A No. 1 brine pump and a No. 2 brine pump are fixedly connected to each side of the brine tank. The input end of the No. 1 brine pump is fixedly connected to the secondary outlet of the brine tank, and its output end is fixedly connected to the brine tank via a return pipe. The input end of the No. 2 brine pump is fixedly connected to the main outlet of the brine tank, and its output end is fixedly connected to the jacket of a thin-film evaporator via a No. 4 pipe. The outer outlet of the thin-film evaporator is fixedly connected to the brine tank, and the bottom outlet of the thin-film evaporator is fixedly connected to a neutralization tank via a No. 5 pipe. The use of a wound-type evaporative condenser improves heat exchange efficiency. Multiple evaporative condensers are connected in parallel to achieve automatic refrigerant vapor distribution. A buffer system is formed by interlocking an ammonia cylinder, an auxiliary ammonia storage tank, and a double shut-off valve, which can quickly isolate the ammonia source in case of emergency shutdown. Furthermore, the closed-loop system using low-temperature brine as the medium effectively reduces energy consumption, thus preventing the waste of cooling capacity caused by intermittent production.

[0005] According to the present invention, a cooling device for precipitation of phenylhydrazine hydrochloride mother liquor includes a reciprocating ice compressor and a screw ice compressor, which are fixedly connected by a connecting pipe. The reciprocating ice compressor and the screw ice compressor form a cascade system. When the reciprocating ice compressor is under low load, it switches to a cold storage mode and delivers excess cold energy to the screw ice compressor through the connecting pipe, reducing restart energy consumption.

[0006] According to the present invention, a cooling device for precipitation of phenylhydrazine hydrochloride mother liquor includes multiple oil separators and multiple evaporative condensers, with the oil separators and evaporative condensers connected in series. This three-stage series oil separator reduces the amount of residual lubricating oil in the ammonia gas, preventing the oil film from reducing the heat exchange efficiency of the evaporative condenser.

[0007] According to the present invention, a cooling device for precipitation of phenylhydrazine hydrochloride mother liquor includes three ammonia cylinders arranged side by side. The outlets of the three ammonia cylinders are fixedly connected to an absorption water tank via discharge pipes. The parallel pipes enable staged pressure relief, preventing concentrated release from overloading the absorption water tank. The exhaust gas from the three ammonia cylinders enters the absorption water tank through a collecting pipe, thereby improving the ammonia recovery rate.

[0008] According to the present invention, a cooling device for precipitation of phenylhydrazine hydrochloride mother liquor is provided, wherein an expansion valve is installed at the connection between the thin-film evaporator and the No. 3 pipeline, and a gas-liquid separator is fixedly connected to the top outlet of the thin-film evaporator. The expansion valve allows liquid ammonia to be converted from a high-pressure liquid state to a low-temperature, low-pressure mist mixture, thereby providing a cooling source for the thin-film evaporator.

[0009] According to the present invention, a cooling device for precipitating phenylhydrazine hydrochloride mother liquor is provided, wherein the outer outlet of the gas-liquid separator is fixedly connected to the output end of the refrigeration compressor, and the bottom outlet of the gas-liquid separator is fixedly connected to pipeline No. 4. The separated dry ammonia gas is returned to the refrigeration compressor via the outer outlet, and the volatile substances containing HCl are treated by the gas-liquid separator.

[0010] According to the present invention, a cooling device for precipitation of phenylhydrazine hydrochloride mother liquor is provided. An external circulating pump is fixedly connected to the evaporative condenser, and the output end of the circulating pump is fixedly connected to the evaporative condenser. The evaporative condenser adopts a wound-type heat exchange structure and has high condensation capacity. The wound-type condenser heat exchange design increases the heat exchange area, shortens the contact path between the cooling medium and the mother liquor, and improves heat exchange efficiency. Furthermore, the use of titanium enhances the corrosion resistance of the heat exchange equipment while also providing good heat transfer performance.

[0011] According to the present invention, a cooling device for precipitation of phenylhydrazine hydrochloride mother liquor includes an oil separator with a fixedly connected secondary outlet to an oil reservoir, and the top outlet of the oil reservoir being fixedly connected to a connecting pipe. The lubricating oil separated by the oil separator is returned to the refrigeration compressor lubrication system, ensuring continuous lubrication of moving parts and reducing mechanical wear.

[0012] Beneficial effects: Compared with existing technologies, this novel cooling device for precipitating phenylhydrazine hydrochloride mother liquor uses a wound-type evaporative condenser to improve heat exchange efficiency. At the same time, multiple evaporative condensers are connected in parallel to achieve automatic diversion of refrigerant vapor. A buffer system is formed by interlocking an ammonia tank, an auxiliary ammonia storage tank, and a double shut-off valve, which can quickly isolate the ammonia source in case of emergency shutdown. In addition, the use of a closed-loop system with low-temperature brine medium can effectively reduce energy consumption, thereby preventing the waste of cooling capacity caused by intermittent production. Attached Figure Description

[0013] The present invention will be further described below with reference to the accompanying drawings and embodiments;

[0014] Figure 1 This is a complete structural diagram of the cooling device for precipitation of phenylhydrazine hydrochloride mother liquor according to this utility model;

[0015] Figure 2This is a structural diagram of the refrigeration compressor and oil separator of the cooling device for precipitation of phenylhydrazine hydrochloride mother liquor according to this utility model;

[0016] Figure 3 This is a structural diagram of the thin-film evaporator and brine tank of the cooling device for precipitation of phenylhydrazine hydrochloride mother liquor according to this utility model;

[0017] Figure 4 This is a diagram of the circulating cooling structure of the cooling device for precipitation of phenylhydrazine hydrochloride mother liquor according to this invention.

[0018] Legend:

[0019] 1. Refrigeration compressor; 2. Oil separator; 3. Evaporative condenser; 4. Pipeline 1; 5. Auxiliary ammonia receiver; 6. Pipeline 2; 7. Ammonia tank; 8. Pipeline 3; 9. Thin-film evaporator; 10. Brine tank; 11. Brine pump 1; 12. Brine pump 2; 13. Return pipe; 14. Pipeline 4; 15. Pipeline 5; 16. Neutralization tank; 17. Piston ice machine; 18. Screw ice machine; 19. Discharge pipe; 20. Absorption water tank; 21. Expansion valve; 22. Connecting pipe; 23. Gas-liquid separator; 24. Oil receiver; 25. Shut-off valve; 26. Circulation pump. Detailed Implementation

[0020] This section will describe in detail the specific embodiments of the present utility model. The preferred embodiments of the present utility model are shown in the accompanying drawings. The purpose of the drawings is to supplement the description of the textual part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present utility model, but they should not be construed as limiting the scope of protection of the present utility model.

[0021] Reference Figure 1-4 This utility model provides a cooling device for precipitation of phenylhydrazine hydrochloride mother liquor, comprising: a refrigeration compressor 1, which includes a piston ice machine 17 and a screw ice machine 18, which are fixedly connected by a connecting pipe 22; an oil separator 2 is fixedly connected to the output end of the refrigeration compressor 1; an oil reservoir 24 is fixedly connected to the secondary outlet of the oil separator 2; the top outlet of the oil reservoir 24 is fixedly connected to the connecting pipe 22; an evaporative condenser 3 is fixedly connected to the main outlet of the oil separator 2; an auxiliary ammonia reservoir 5 is fixedly connected to the outlet of the evaporative condenser 3 via a first pipe 4; an ammonia cylinder 7 is fixedly connected to the outlet of the auxiliary ammonia reservoir 5 via a second pipe 6; a shut-off valve 25 is provided at the connection between the ammonia cylinder 7 and the second pipe 6; and a thin-film evaporator 9 is fixedly connected to the outlet of the ammonia cylinder 7 via a third pipe 8.

[0022] Specifically, liquid ammonia is used as the refrigerant. Cooling is generated by the vaporization of stored liquid ammonia. The vaporized ammonia is compressed back to the liquid ammonia storage tank by multiple refrigeration compressors of different models 1. At the same time, the system is connected to the ammonia unit in the workshop. Cooling is achieved by continuously vaporizing liquid ammonia into ammonia gas and consuming it. The evaporative condenser 3 cools the gaseous ammonia into liquid ammonia, which flows into the ammonia tank 7 for temporary storage. It works in conjunction with the auxiliary ammonia storage tank 5 to balance the ammonia quantity in the system. Then, the high-pressure liquid ammonia enters the thin-film evaporator 9 after being throttled by the expansion valve 21.

[0023] The main outlet of the thin-film evaporator 9 is fixedly connected to a brine tank 10. A first brine pump 11 and a second brine pump 12 are fixedly connected to each side of the brine tank 10. The input end of the first brine pump 11 is fixedly connected to the secondary outlet of the brine tank 10. The output end of the first brine pump 11 is fixedly connected to the brine tank 10 through a return pipe 13. The input end of the second brine pump 12 is fixedly connected to the main outlet of the brine tank 10. The output end of the second brine pump 12 is fixedly connected to the jacket of the thin-film evaporator 9 through a fourth pipe 14. The outer outlet of the thin-film evaporator 9 is fixedly connected to the brine tank 10. The bottom outlet of the thin-film evaporator 9 is fixedly connected to a neutralization tank 16 through a fifth pipe 15.

[0024] Specifically, calcium chloride aqueous solution is used as the refrigerant. The brine tank 10 delivers low-temperature brine to the jacket of the thin-film evaporator 9 through the second brine pump 12. The brine that absorbs heat and heats up returns to the brine tank 10 for recooling, forming a closed loop. The acidic liquid is neutralized through the neutralization tank 16.

[0025] There are multiple oil separators 2 and multiple evaporative condensers 3. The multiple oil separators 2 are connected to each other in sequence, and the multiple evaporative condensers 3 are connected to each other in sequence. A circulation pump 26 is fixedly connected to the outside of the evaporative condenser 3. The output end of the circulation pump 26 is fixedly connected to the evaporative condenser 3. The evaporative condenser 3 adopts a wound heat exchange structure and has high condensation performance. There are three ammonia cylinders 7 arranged side by side. The outlets of the three ammonia cylinders 7 are fixedly connected to the absorption water tank 20 through the discharge pipe 19.

[0026] Specifically, the three-stage series oil separator 2 can reduce the amount of lubricating oil residue in ammonia gas, and avoid the oil film from reducing the heat exchange efficiency of the evaporative condenser 3. The evaporative condenser 3, which adopts a winding heat exchange structure, has high condensation properties, which improves the liquefaction efficiency of ammonia vapor. The three parallel ammonia cylinders 7 are connected in parallel to the absorption water tank 20 through the discharge pipeline 19 to realize the storage of ammonia liquid.

[0027] An expansion valve 21 is installed at the connection between the thin film evaporator 9 and the third pipeline 8. The top outlet of the thin film evaporator 9 is fixedly connected to a gas-liquid separator 23. The outer outlet of the gas-liquid separator 23 is fixedly connected to the output end of the refrigeration compressor 1. The bottom outlet of the gas-liquid separator 23 is fixedly connected to the fourth pipeline 14.

[0028] Specifically, the expansion valve 21 can convert liquid ammonia from a high-pressure liquid state to a low-temperature, low-pressure mist mixture, thereby providing a cold source for the thin-film evaporator 9, and the gas-liquid separator 23 can treat volatile substances containing HCl.

[0029] Working principle: The refrigeration compressor 1 draws in low-temperature ammonia gas from the gas-liquid separator 23. After compression, the ammonia gas passes through the oil separator 2 to remove oil. The high-temperature, high-pressure ammonia gas then enters the evaporative condenser 3. The lubricating oil separated by the oil separator 2 returns to the lubrication system of the refrigeration compressor 1. The evaporative condenser 3 cools the gaseous ammonia into liquid ammonia, which flows into the ammonia tank 7 for temporary storage. It also works with the auxiliary ammonia storage tank 5 to balance the ammonia level in the system. Next, the high-pressure liquid ammonia enters the thin-film evaporator 9 after being throttled by the expansion valve 21. It absorbs heat from the mother liquor and evaporates into low-temperature ammonia gas. The evaporated gas-liquid mixture returns to the gas-liquid separator 23. The gas phase re-enters the refrigeration compressor 1 for circulation. Then, the brine tank 10 delivers low-temperature brine to the jacket of the thin-film evaporator 9 through the second brine pump 12. The brine that absorbs heat and heats up returns to the brine tank 10 for re-cooling, forming a closed loop.

[0030] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A cooling device for precipitation of phenylhydrazine hydrochloride mother liquor, characterized in that, include: A refrigeration compressor (1) is fixedly connected to an oil separator (2) at its output end. The main outlet of the oil separator (2) is fixedly connected to an evaporative condenser (3). The outlet of the evaporative condenser (3) is fixedly connected to an auxiliary ammonia storage tank (5) via a first pipeline (4). The outlet of the auxiliary ammonia storage tank (5) is fixedly connected to an ammonia cylinder (7) via a second pipeline (6). A shut-off valve (25) is provided at the connection between the ammonia cylinder (7) and the second pipeline (6). The outlet of the ammonia cylinder (7) is fixedly connected to a thin-film evaporator (9) via a third pipeline (8). The main outlet of the thin-film evaporator (9) is fixedly connected to a brine tank (10). A first brine pump (11) and a second brine pump (12) are fixedly connected to each side of the brine tank (10). The input end of the first brine pump (11) is fixedly connected to the secondary outlet of the brine tank (10). The output end of the first brine pump (11) is fixedly connected to the brine tank (10) through a return pipe (13). The input end of the second brine pump (12) is fixedly connected to the main outlet of the brine tank (10). The output end of the second brine pump (12) is fixedly connected to the jacket of the thin-film evaporator (9) through a fourth pipe (14). The outer outlet of the thin-film evaporator (9) is fixedly connected to the brine tank (10). The bottom outlet of the thin-film evaporator (9) is fixedly connected to a neutralization tank (16) through a fifth pipe (15).

2. The cooling device for precipitation of phenylhydrazine hydrochloride mother liquor according to claim 1, characterized in that, The refrigeration compressor (1) includes a piston ice machine (17) and a screw ice machine (18), which are fixedly connected by a connecting pipe (22).

3. The cooling device for precipitation of phenylhydrazine hydrochloride mother liquor according to claim 1, characterized in that, There are multiple oil separators (2) and multiple evaporative condensers (3), and the multiple oil separators (2) are connected to each other in sequence, and the multiple evaporative condensers (3) are connected to each other in sequence.

4. The cooling device for precipitation of phenylhydrazine hydrochloride mother liquor according to claim 1, characterized in that, There are three ammonia cylinders (7) arranged side by side, and the outlets of the three ammonia cylinders (7) are fixedly connected to the absorption water tank (20) through the discharge pipe (19).

5. A cooling device for precipitation of phenylhydrazine hydrochloride mother liquor according to claim 1, characterized in that, An expansion valve (21) is provided at the connection between the thin film evaporator (9) and the third pipeline (8), and a gas-liquid separator (23) is fixedly connected to the top outlet of the thin film evaporator (9).

6. A cooling device for precipitation of phenylhydrazine hydrochloride mother liquor according to claim 5, characterized in that, The outer outlet of the gas-liquid separator (23) is fixedly connected to the output end of the refrigeration compressor (1), and the bottom outlet of the gas-liquid separator (23) is fixedly connected to the fourth pipeline (14).

7. A cooling device for precipitation of phenylhydrazine hydrochloride mother liquor according to claim 1, characterized in that, The evaporative condenser (3) is externally fixedly connected to a circulating pump (26), the output end of which is fixedly connected to the evaporative condenser (3). The evaporative condenser (3) adopts a wound heat exchange structure and has high condensation performance.

8. A cooling device for precipitation of phenylhydrazine hydrochloride mother liquor according to claim 1, characterized in that, The secondary outlet of the oil separator (2) is fixedly connected to an oil reservoir (24), and the top outlet of the oil reservoir (24) is fixedly connected to a connecting pipe (22).

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