Purification system for primary crude product of diaminomaleonitrile

Abstract

The utility model discloses a purification system for a primary crude product of diaminomaleonitrile, which relates to the technical field of purification and comprises a crude product crystallizing tank, an automatic multifunctional filter press, a solvent tank, a washing water temporary storage tank, a crude product dryer and a dust removal condensing system, a liquid inlet of the crude product crystallizing tank is communicated with a liquid outlet of the diaminomaleonitrile reaction system, a liquid outlet of the crude product crystallizing tank is communicated with a feeding hole of the automatic multifunctional filter press, a liquid inlet of the solvent tank is communicated with the solvent tank area through a pipeline, a liquid outlet of the solvent tank is communicated with a feeding hole of the automatic multifunctional filter press, and a liquid outlet of the automatic multifunctional filter press is communicated with a liquid outlet of the crude product crystallizing tank. A liquid outlet of the automatic multifunctional filter press is communicated with a liquid inlet of the washing water temporary storage tank; a discharge hole of the automatic multifunctional filter press is communicated with the crude product dryer; and an air outlet of the crude product dryer is communicated with the dust removal condensation system. The device is reasonable in design, simplifies equipment, reduces operation procedures, improves the operation automation level, and has the advantages of energy conservation and environmental protection.

Description

Technical Field

[0001] The utility model relates to the technical field of purification, and more specifically to the technical field of a purification system for a crude diaminomaleonitrile product. Background Art

[0002] Diaminomaleonitrile is a brown crystalline powder used as a starting material for the synthesis of various heterocyclic compounds. One method for preparing diaminomaleonitrile is to polymerize it using a catalyst, not limited to one type, in the presence of an organic solvent, with the addition of liquid hydrocyanic acid, and controlled reaction temperature and pressure to produce diaminomaleonitrile.

[0003] After the diaminomaleonitrile polymerization reaction is completed, the added catalyst and the oligomeric impurities generated by the reaction need to be separated from the polymerization reaction liquid to perform the first crude diaminomaleonitrile purification. The original process is to first place the diaminomaleonitrile polymerization reaction liquid into a crude product crystallization tank pre-added with desalted water, then stir and cool it for crystallization. After the crude product crystallization liquid is centrifuged in a crude product centrifuge, the residual solvent in the centrifuged solid material is washed with desalted water to obtain a crude crystallization product. The crude crystallization product is transferred to a reflux impurity removal kettle, and a solvent is added to heat and dissolve it, and then the temperature is lowered. Then, it is placed in an impurity removal centrifuge for centrifugation. After the centrifugation is completed, the residual solvent in the centrifuged solid material is washed with desalted water, and the centrifuged solid material is placed in a crude product dryer for normal pressure drying to obtain a crude diaminomaleonitrile.

[0004] The existing process system involved numerous pieces of equipment and was cumbersome to operate. The secondary water washing of the solids produced a significant amount of organic wastewater, necessitating high energy and time consumption in subsequent processing steps, placing a heavy financial burden on the company. The high water content of the crude product led to prolonged drying times and high energy consumption. This did not meet energy-saving requirements, and because water, catalysts, and oligomer impurities are incompatible, some impurities dissolved in the solvent were displaced during rinsing, resulting in a high impurity content in the primary crude product and a certain degree of compromise in product purity. The organic waste gases emitted during the drying and centrifugation processes were harmful to the health of on-site operators and were detrimental to the environment. Utility Model Content

[0005] The purpose of the utility model is to solve the above technical problems and provide a purification system for a crude diaminomaleonitrile product.

[0006] In order to achieve the above-mentioned purpose, the present invention specifically adopts the following technical solutions:

[0007] The utility model provides a crude diaminomaleonitrile purification system, comprising a crude product crystallization tank, an automatic multifunctional filter press, a solvent tank, a washing water temporary storage tank, a crude product dryer, and a dust removal and condensation system;

[0008] The liquid inlet of the crude product crystallization tank is connected to the liquid outlet of the diaminomaleonitrile reaction system, the liquid outlet of the crude product crystallization tank is connected to the feed port of the automatic multifunctional filter press, the liquid inlet of the solvent tank is connected to the solvent tank area through a pipeline, and the liquid outlet of the solvent tank is connected to the feed port of the automatic multifunctional filter press;

[0009] The air outlet of the automatic multifunctional filter press, the air outlet of the washing water temporary storage tank, and the air outlet of the solvent tank are all connected to the tail gas treatment system;

[0010] The liquid outlet of the automatic multifunctional filter press is connected to the liquid inlet of the washing water temporary storage tank; the material filtered by the automatic multifunctional filter press enters the coarse product dryer through the outlet of the automatic multifunctional filter press, and the air outlet of the coarse product dryer is connected to the dust removal condensation system.

[0011] Specifically, the diaminomaleonitrile polymerization reaction liquid from the diaminomaleonitrile reaction system is placed into a crude product crystallization tank through a liquid inlet, stirred, cooled, and crystallized, and then placed into an automatic multifunctional filter press. The fully automatic filter press is operated to perform a first filter press on the crystallization liquid. The filter cake after the first filter press is rinsed with desalted water and then subjected to a second filter press. The filter cake is a diaminomaleonitrile crude product containing a certain amount of water. In the fully automatic filter press, the diaminomaleonitrile filter cake after the second filter press is stirred and heated with a solvent from a solvent tank, kept warm for a period of time, and then cooled and filtered for a third time. After the filter press is completed, the filter cake is rinsed with a solvent and then filtered for a fourth time. The filter cake is broken up and placed in a crude product dryer for vacuum drying.

[0012] In one embodiment, the solvent recovered by the dust removal and condensation system is returned to the solvent tank through a pipeline, and the liquid outlet of the wash water temporary storage tank is connected to the crude product crystallization tank through a pipeline.

[0013] Specifically, the solvent gas generated during drying in the crude product dryer is condensed by a dust removal and condensation system and then returned to the solvent tank for reuse. The filter cake after drying is the primary crude diaminomaleonitrile product. The third and fourth press filtrates, containing oligomer impurities and spent catalyst, are then processed in the solvent recovery system of the next process, completing the initial purification of the crude diaminomaleonitrile.

[0014] In one embodiment, the crude product crystallization tank includes a tank body, a crystallization material inlet arranged at the top of the tank body, a crystallization buffer inlet arranged at the top of the tank body, a crystallization material outlet arranged at the bottom of the tank body, a stirring mechanism arranged in the tank body, and a drive motor arranged at the top of the tank body to drive the stirring mechanism to rotate, the tank body includes an inner shell and an outer shell, the inner shell and the outer shell form a freezing cavity, the outer shell is provided with a chilled water inlet pipe and a chilled water outlet pipe communicated with the inside of the freezing cavity, and the tank body is further provided with a first low-pressure nitrogen inlet. The first low-pressure nitrogen inlet is to replace the air inside the crude product crystallization tank with nitrogen, mainly to allow the crude product crystallization tank to have the gas space filled with nitrogen, isolate the crystallization material from contact with air, and reduce the possibility of combustion and explosion of solvent volatile gas in the polymerization reaction liquid.

[0015] In one embodiment, the automatic multifunctional filter press includes a filter press housing, a filter press material feed port and a second tail gas outlet provided at the top of the filter press housing, a filter press liquid outlet provided at the bottom of a side wall of the filter press housing, and a filter press material discharge port provided on the side wall of the filter press housing and located above the filter press liquid outlet;

[0016] The filter press material feed port is connected to the crystallization material outlet, the solvent tank outlet, the low-pressure nitrogen pipe and the washing desalted water pipe respectively;

[0017] The filter press outlet is respectively connected to the washing water temporary storage tank, the impurity removal filtrate recovery and processing pipeline, and the solvent filtrate recovery and processing pipeline.

[0018] In one embodiment, the solvent tank includes a solvent tank housing, a second low-pressure nitrogen inlet disposed at the top of the solvent tank housing, a solvent feed port disposed at the top of the solvent tank housing (sharing a pipe with the solvent from the tank area), a first tail gas outlet disposed at the top of the solvent tank housing, and a solvent liquid outlet disposed at the bottom of the solvent tank housing;

[0019] The first low-pressure nitrogen inlet and the second low-pressure nitrogen inlet are in communication with a nitrogen source;

[0020] The first tail gas outlet and the second tail gas outlet are connected to the tail gas treatment system through a pipeline;

[0021] The solvent outlet is connected to the filter press material feed port through a pipeline.

[0022] In one embodiment, the wash water temporary storage tank includes a temporary storage tank shell, a temporary storage liquid inlet provided at the top of the temporary storage tank shell, a temporary storage air outlet provided at the top of the temporary storage tank shell, and a temporary storage liquid outlet provided at the bottom of the temporary storage tank shell;

[0023] The temporary storage liquid inlet is connected to the filter press liquid outlet through a pipeline;

[0024] The temporary gas outlet is connected to the exhaust gas treatment system;

[0025] The temporary liquid outlet is connected to the crystallization buffer liquid inlet through a pipeline.

[0026] In one embodiment, the crude product dryer includes a drying shell, a feed bin disposed on the top of the drying shell, and a discharge bin disposed on the bottom of the drying shell.

[0027] In one embodiment, multiple layers of interconnected dry hot water pipe assemblies are evenly distributed inside the drying shell, and a dry hot water inlet pipe and a dry hot water outlet pipe connected to the dry hot water pipe assemblies are provided outside the drying shell.

[0028] In one embodiment, the tops of the drying shell, the feed bin, and the discharge bin are all provided with outlet branch pipes, the three outlet branch pipes are connected to the outlet main pipe, and the outlet main pipe is connected to the dust removal and condensation system.

[0029] In one embodiment, the dust removal and condensation system includes a dust collector, a condenser, and a condensate receiving tank;

[0030] The air outlet main pipe is connected to the air inlet of the dust collector, the air outlet of the dust collector is connected to the air inlet of the condenser, the air outlet of the condenser is connected to the vacuum tube unit, the condensate outlet of the condenser is connected to the liquid inlet of the condensate receiving tank, and the liquid outlet of the condensate receiving tank is connected to the solvent feed port of the solvent tank.

[0031] The beneficial effects of the utility model are as follows:

[0032] 1. The utility model has a reasonable design, simplifies the equipment, reduces the operating procedures, and improves the automation of operation; reduces the material loss and safety risks caused by leakage caused by multi-device material transfer, reduces the investment in equipment such as machines and pumps, and reduces the land occupied by the factory.

[0033] 2. The utility model adopts a solvent secondary washing solid material process, which effectively reduces the generation and treatment volume of wastewater. When the crude product is dried, the selected impurity removal solvent has a lower boiling point than water (when dichloroethane is selected as the impurity removal solvent, the boiling point of the impurity removal solvent is 17°C lower than that of water). When the crude product is dried, the drying time is shorter than the water washing process, energy consumption is reduced, and carbon emission reduction is beneficial. The impurity removal solvent used for washing is recycled and reused through conventional distillation, which can save the amount of impurity removal solvent and thus save costs.

[0034] 3. The filtration process is carried out in a fully enclosed environment of the filter press, and the operators are not harmed by organic gases; the wet crude product is dried in a vacuum-sealed manner, and the organic gas is collected and recycled after condensation, which reduces the recycling process and reduces the emission of unorganized organic waste gas, making it safe, environmentally friendly and energy-saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0036] Figure 1 It is a structural diagram of the utility model;

[0037] Figure 2 It is a structural diagram of the crude product crystallization tank;

[0038] Figure 3 It is a structural diagram of a dynamic multifunctional filter press;

[0039] Figure 4 It is a structural diagram of the solvent tank;

[0040] Figure 5 It is a structural diagram of the wash water temporary storage tank;

[0041] Figure 6 It is a schematic diagram of the structure of the crude product dryer;

[0042] Figure 7 It is a structural diagram of the dust removal and condensation system;

[0043] Reference numerals: 1-crude product crystallization tank, 2-solvent tank, 3-wash water temporary storage tank, 4-automatic multifunctional filter press, 5-dust removal and condensation system, 6-crude product dryer;

[0044] 11-inner housing, 12-outer housing, 13-stirring mechanism, 14-crystallization material liquid outlet, 15-chilled water liquid inlet pipe, 16-chilled water liquid outlet pipe, 17-crystallization buffer liquid inlet, 18-crystallization material liquid inlet, 19-driving motor;

[0045] 21-first tail gas outlet, 22-second low-pressure nitrogen inlet, 23-solvent tank shell, 24-solvent liquid outlet, 25-solvent feed inlet;

[0046] 31-temporary liquid outlet, 32-temporary liquid inlet, 33-temporary gas outlet, 34-temporary tank shell;

[0047] 41 - filter press material feed port, 42 - second tail gas outlet, 43 - filter press housing, 44 - filter press material discharge port, 45 - filter press liquid outlet, 46 - solvent filtrate recovery processing pipeline, 47 - impurity removal filtrate recovery processing pipeline, 48 - washing desalted water pipe, 49 - low-pressure nitrogen pipe;

[0048] 51-dust collector, 52-condenser, 53-condensate receiving tank;

[0049] 61-drying shell, 62-feeding bin, 63-air outlet main pipe, 64-drying hot water inlet pipe, 65-discharge bin, 66-drying hot water outlet pipe. DETAILED DESCRIPTION

[0050] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0051] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0052] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. In addition, the terms "first," "second," etc. are used only to distinguish the descriptions and are not to be understood as indicating or implying relative importance.

[0053] In the description of the embodiments of the present invention, it should be noted that the terms "inside", "outside", "upper", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the product of the present invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as a limitation on the present invention.

[0054] Example 1

[0055] like Figures 1 to 7 As shown, this embodiment provides a purification system for a crude diaminomaleonitrile product, comprising a crude product crystallization tank 1, an automatic multifunctional filter press 4, a solvent tank 2, a washing water temporary storage tank 3, a crude product dryer 6, and a dust removal and condensation system 5;

[0056] The liquid inlet of the crude product crystallization tank 1 is communicated with the liquid outlet of the diaminomaleonitrile reaction system, the liquid outlet of the crude product crystallization tank 1 is communicated with the feed port of the automatic multifunctional filter press 4, the liquid inlet of the solvent tank 2 is communicated with the solvent tank area through a pipeline, and the liquid outlet of the solvent tank 2 is communicated with the feed port of the automatic multifunctional filter press 4;

[0057] The air outlet of the automatic multifunctional filter press 4, the air outlet of the washing water temporary storage tank 3, and the air outlet of the solvent tank 2 are all connected to the tail gas treatment system;

[0058] The liquid outlet of the automatic multifunctional filter press 4 is connected to the liquid inlet of the wash water storage tank 3; the material filtered by the automatic multifunctional filter press 4 enters the coarse product dryer 6 through the discharge port of the automatic multifunctional filter press 4, and the air outlet of the coarse product dryer 6 is connected to the dust removal condensation system 5.

[0059] Specifically, the diaminomaleonitrile polymerization reaction liquid from the diaminomaleonitrile reaction system is placed into a crude product crystallization tank 1 through a liquid inlet, stirred, cooled, and crystallized, and then placed into an automatic multifunctional filter press 4. The fully automatic filter press is operated to perform a first filter press on the crystallization liquid. The filter cake after the first filter press is rinsed with desalted water and then subjected to a second filter press. The filter cake is a diaminomaleonitrile crude product containing a certain amount of water. In the fully automatic filter press, the diaminomaleonitrile filter cake after the second filter press is stirred and heated with the solvent from the solvent tank 2, kept warm for a period of time, and then cooled and filtered for a third time. After the filter press is completed, the filter cake is rinsed with a solvent and then filtered for a fourth time. The filter cake is broken up and placed in a crude product dryer 6 for vacuum drying.

[0060] Example 2

[0061] like Figures 1 to 7 As shown, this embodiment provides a purification system for a crude diaminomaleonitrile product, comprising a crude product crystallization tank 1, an automatic multifunctional filter press 4, a solvent tank 2, a washing water temporary storage tank 3, a crude product dryer 6, and a dust removal and condensation system 5;

[0062] The liquid inlet of the crude product crystallization tank 1 is communicated with the liquid outlet of the diaminomaleonitrile reaction system, the liquid outlet of the crude product crystallization tank 1 is communicated with the feed port of the automatic multifunctional filter press 4, the liquid inlet of the solvent tank 2 is communicated with the solvent tank area through a pipeline, and the liquid outlet of the solvent tank 2 is communicated with the feed port of the automatic multifunctional filter press 4;

[0063] The air outlet of the automatic multifunctional filter press 4, the air outlet of the washing water temporary storage tank 3, and the air outlet of the solvent tank 2 are all connected to the tail gas treatment system;

[0064] The liquid outlet of the automatic multifunctional filter press 4 is connected to the liquid inlet of the wash water storage tank 3; the material filtered by the automatic multifunctional filter press 4 enters the coarse product dryer 6 through the discharge port of the automatic multifunctional filter press 4, and the air outlet of the coarse product dryer 6 is connected to the dust removal condensation system 5.

[0065] The solvent recovered by the dust removal and condensation system 5 is returned to the solvent tank 2 through a pipeline, and the liquid outlet of the wash water temporary storage tank 3 is connected to the crude product crystallization tank 1 through a pipeline.

[0066] Specifically, the solvent gas generated by drying in the crude product dryer 6 is condensed by the dust removal and condensation system 5 and then returned to the solvent metering tank for reuse. The filter cake after drying is the primary crude diaminomaleonitrile product. The third and fourth press filtrates are the impurity-removed filtrates containing oligomer impurities and spent catalyst, and are then processed in the solvent recovery system of the next process. This completes the initial purification of the crude diaminomaleonitrile.

[0067] Example 3

[0068] like Figure 2 As shown, this embodiment is further optimized based on embodiment 2, specifically:

[0069] The crude product crystallization tank 1 includes a tank body, a crystallization material liquid inlet 18 arranged at the top of the tank body, a crystallization buffer liquid inlet 17 arranged at the top of the tank body, a crystallization material liquid outlet 14 arranged at the bottom of the tank body, a stirring mechanism 13 arranged in the tank body, and a drive motor 19 arranged at the top of the tank body to drive the stirring mechanism 13 to rotate. The tank body includes an inner shell 11 and an outer shell 12, and the inner shell 11 and the outer shell 12 form a freezing cavity. The outer shell 12 is provided with a chilled water inlet pipe 15 and a chilled water outlet pipe 16 connected to the inside of the freezing cavity, and the tank body is also provided with a first low-pressure nitrogen inlet.

[0070] Example 4

[0071] like Figure 3 As shown, this embodiment is further optimized based on embodiment 3, specifically:

[0072] The automatic multifunctional filter press 4 includes a filter press housing 43, a filter press material feed port 41 and a second tail gas outlet 42 provided at the top of the filter press housing 43, a filter press liquid outlet 45 provided at the bottom of the side wall of the filter press housing 43, and a filter press material discharge port 44 provided on the side wall of the filter press housing 43 and located above the filter press liquid outlet 45;

[0073] The filter press material discharge port 44 is connected to the feed port of the crude product dryer 6;

[0074] The filter press material feed port 41 is connected to the crystallization material outlet 14, the liquid outlet of the solvent tank 2, the low-pressure nitrogen pipe 49 and the washing desalted water pipe 48 respectively;

[0075] The filter press outlet 45 is connected to the washing water temporary storage tank 3, the impurity removal filtrate recovery and processing pipeline 47, and the solvent filtrate recovery and processing pipeline 46 respectively.

[0076] Example 5

[0077] like Figure 4 As shown, this embodiment is further optimized based on the embodiment 4, specifically:

[0078] The solvent tank 2 includes a solvent tank housing 23, a second low-pressure nitrogen inlet 22 provided at the top of the solvent tank housing 23, a solvent feed port 25 provided at the top of the solvent tank housing 23, a first tail gas outlet 21 provided at the top of the solvent tank housing 23, and a solvent liquid outlet 24 provided at the bottom of the solvent tank housing 23;

[0079] The first low-pressure nitrogen inlet and the second low-pressure nitrogen inlet 22 are in communication with a nitrogen source;

[0080] The first tail gas outlet 21 and the second tail gas outlet 42 are connected to the tail gas treatment system through a pipeline;

[0081] The solvent outlet 24 is connected to the filter press material feed port 41 through a pipeline.

[0082] Example 6

[0083] like Figure 5 As shown, this embodiment is further optimized based on embodiment 5, specifically:

[0084] The washing water temporary storage tank 3 includes a temporary storage tank shell 34, a temporary storage liquid inlet 32 ​​provided at the top of the temporary storage tank shell 34, a temporary storage air outlet 33 provided at the top of the temporary storage tank shell 34, and a temporary storage liquid outlet 31 provided at the bottom of the temporary storage tank shell 34;

[0085] The temporary storage liquid inlet 32 ​​is connected to the filter press liquid outlet 45 through a pipeline;

[0086] The temporary gas outlet 33 is connected to the exhaust gas treatment system;

[0087] The temporary liquid outlet 31 is connected to the crystallization buffer liquid inlet 17 through a pipeline.

[0088] Example 7

[0089] like Figure 6 As shown, this embodiment is further optimized based on Example 6, specifically:

[0090] The crude product dryer 6 includes a drying shell 61 , a feed bin 62 disposed on the top of the drying shell 61 , and a discharge bin 65 disposed on the bottom of the drying shell 61 .

[0091] Multiple layers of interconnected dry hot water pipe assemblies are evenly distributed inside the dry shell 61 , and a dry hot water inlet pipe 64 and a dry hot water outlet pipe 66 communicating with the dry hot water pipe assemblies are provided outside the dry shell 61 .

[0092] The tops of the drying shell 61 , the feed bin 62 , and the discharge bin 65 are all provided with outlet branch pipes. The three outlet branch pipes are connected to the outlet main pipe 63 , and the outlet main pipe 63 is connected to the dust removal and condensation system 5 .

[0093] Example 8

[0094] like Figure 7 As shown, this embodiment is further optimized based on Example 7, specifically:

[0095] The dust removal and condensation system 5 includes a dust collector 51, a condenser 52, and a condensate receiving tank 53;

[0096] The air outlet main pipe 63 is connected to the air inlet of the dust collector 51, the air outlet of the dust collector 51 is connected to the air inlet of the condenser 52, the air outlet of the condenser 52 is connected to the vacuum tube unit, the condensate outlet of the condenser 52 is connected to the liquid inlet of the condensate receiving tank 53, and the liquid outlet of the condensate receiving tank 53 is connected to the solvent feed port 25 at the top of the solvent tank shell 23.

Claims

1. A system for purifying a crude diaminomaleonitrile product, characterized in that: It includes a crude product crystallization tank (1), an automatic multifunctional filter press (4), a solvent tank (2), a washing water temporary storage tank (3), a crude product dryer (6), and a dust removal condensation system (5); The liquid inlet of the crude product crystallization tank (1) is connected to the liquid outlet of the diaminomaleonitrile reaction system, the liquid outlet of the crude product crystallization tank (1) is connected to the feed port of the automatic multifunctional filter press (4), the liquid inlet of the solvent tank (2) is connected to the solvent tank area through a pipeline, and the liquid outlet of the solvent tank (2) is connected to the feed port of the automatic multifunctional filter press (4); The air outlet of the automatic multifunctional filter press (4), the air outlet of the washing water temporary storage tank (3), and the air outlet of the solvent tank (2) are all connected to the tail gas treatment system; The liquid outlet of the automatic multifunctional filter press (4) is connected to the liquid inlet of the washing water temporary storage tank (3); the material filtered by the automatic multifunctional filter press (4) enters the crude product dryer (6) through the discharge port of the automatic multifunctional filter press (4), and the air outlet of the crude product dryer (6) is connected to the dust removal condensation system (5).

2. A purification system for a crude diaminomaleonitrile product according to claim 1, characterized in that, The solvent recovered by the dust removal and condensation system (5) is returned to the solvent tank (2) through a pipeline, and the liquid outlet of the wash water temporary storage tank (3) is connected to the crude product crystallization tank (1) through a pipeline.

3. A purification system for a crude diaminomaleonitrile product according to claim 1, characterized in that, The crude product crystallization tank (1) comprises a tank body, a crystallization material liquid inlet (18) arranged at the top of the tank body, a crystallization buffer liquid inlet (17) arranged at the top of the tank body, a crystallization material liquid outlet (14) arranged at the bottom of the tank body, a stirring mechanism (13) arranged in the tank body, and a driving motor (19) arranged at the top of the tank body for driving the stirring mechanism (13) to rotate, the tank body comprises an inner shell (11) and an outer shell (12), the inner shell (11) and the outer shell (12) enclose a freezing cavity, the outer shell (12) is provided with a chilled water inlet pipe (15) and a chilled water outlet pipe (16) connected to the inside of the freezing cavity, and the tank body is also provided with a first low-pressure nitrogen inlet.

4. A purification system for a crude diaminomaleonitrile product according to claim 3, characterized in that, The automatic multifunctional filter press (4) comprises a filter press housing (43), a filter press material feed port (41) and a second tail gas outlet (42) arranged at the top of the filter press housing (43), a filter press liquid outlet (45) arranged at the bottom of the side wall of the filter press housing (43), and a filter press material discharge port (44) arranged on the side wall of the filter press housing (43) and located above the filter press liquid outlet (45); The filter press material discharge port (44) is connected to the feed port of the crude product dryer (6); The filter press material feed port (41) is respectively connected to the crystallization material liquid outlet (14), the liquid outlet of the solvent tank (2), the low-pressure nitrogen pipe (49) and the washing desalted water pipe (48); The filter press outlet (45) is respectively connected to the wash water temporary storage tank (3), the impurity removal filtrate recovery and processing pipeline (47), and the solvent filtrate recovery and processing pipeline (46).

5. A purification system for a crude diaminomaleonitrile product according to claim 4, characterized in that, The solvent tank (2) comprises a solvent tank shell (23), a second low-pressure nitrogen inlet (22) arranged at the top of the solvent tank shell (23), a solvent feed port (25) arranged at the top of the solvent tank shell (23), a first tail gas outlet (21) arranged at the top of the solvent tank shell (23), and a solvent liquid outlet (24) arranged at the bottom of the solvent tank shell (23); The first low-pressure nitrogen inlet and the second low-pressure nitrogen inlet (22) are in communication with a nitrogen source; The solvent feed port (25) is connected to the impurity removal filtrate recovery and processing pipeline (47); The first exhaust gas outlet (21) and the second exhaust gas outlet (42) are connected to the exhaust gas treatment system via a pipeline; The solvent outlet (24) is connected to the filter press material feed port (41) via a pipeline.

6. A purification system for a crude diaminomaleonitrile product according to claim 5, characterized in that, The wash water temporary storage tank (3) comprises a temporary storage tank shell (34), a temporary storage liquid inlet (32) arranged at the top of the temporary storage tank shell (34), a temporary storage air outlet (33) arranged at the top of the temporary storage tank shell (34), and a temporary storage liquid outlet (31) arranged at the bottom of the temporary storage tank shell (34); The temporary storage liquid inlet (32) is connected to the filter press liquid outlet (45) via a pipeline; The temporary gas outlet (33) is in communication with the tail gas treatment system; The temporary liquid outlet (31) is connected to the crystallization buffer liquid inlet (17) via a pipeline.

7. A purification system for a crude diaminomaleonitrile product according to claim 6, characterized in that, The crude product dryer (6) comprises a drying shell (61), a feed bin (62) arranged at the top of the drying shell (61), and a discharge bin (65) arranged at the bottom of the drying shell (61).

8. A purification system for a crude diaminomaleonitrile product according to claim 7, characterized in that, Multiple layers of interconnected dry hot water pipe assemblies are evenly distributed inside the drying shell (61), and a dry hot water inlet pipe (64) and a dry hot water outlet pipe (66) connected to the dry hot water pipe assemblies are provided outside the drying shell (61).

9. A purification system for a crude diaminomaleonitrile product according to claim 7, characterized in that, The tops of the drying shell (61), the feed bin (62), and the discharge bin (65) are all provided with outlet branch pipes. The three outlet branch pipes are connected to the outlet main pipe (63). The outlet main pipe (63) is connected to the dust removal and condensation system (5).

10. A system for purifying a crude diaminomaleonitrile product according to claim 9, characterized in that: The dust removal and condensation system (5) comprises a dust collector (51), a condenser (52), and a condensate receiving tank (53); The main air outlet pipe (63) is connected to the air inlet of the dust collector (51), the air outlet of the dust collector (51) is connected to the air inlet of the condenser (52), the air outlet of the condenser (52) is connected to the vacuum tube unit, the condensate outlet of the condenser (52) is connected to the liquid inlet of the condensate receiving tank (53), and the liquid outlet of the condensate receiving tank (53) is connected to the solvent feed port (25) at the top of the solvent tank shell (23).

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