CN221619444U

CN221619444U - Nitration reaction system

Info

Publication number: CN221619444U
Application number: CN202323657982.5U
Authority: CN
Inventors: 王威; 相子喜; 王杰; 李日翔; 秦兆彬
Original assignee: Shandong Youquan New Material Co ltd
Current assignee: Shandong Youquan New Material Co ltd
Priority date: 2023-12-28
Filing date: 2023-12-28
Publication date: 2024-08-30
Anticipated expiration: 2033-12-28

Abstract

The application relates to the technical field of chemical equipment, and particularly discloses a nitration reaction system which comprises an acid phase separator and a loop reactor. The loop reactor comprises at least one combination of a non-circulating reactor and a circulating pump, wherein the outlet of the circulating pump is communicated with the inlet of the non-circulating reactor, and the inlet of the circulating pump is communicated with the outlet of the non-circulating reactor; or the loop reactor is a loop reactor; the acid phase separator is suitable for separating acid phase, and the inlet of the acid phase separator is communicated with the reaction liquid outlet of the final circulation reactor. The application adopts the loop reactor, can realize continuous feeding, continuous reaction, continuous discharging and separation of an acid phase and an organic phase containing a product, can realize full-automatic control in the whole process, reduces labor cost, ensures personnel safety, ensures low online quantity of nitrified materials in the whole reaction system, ensures higher mass transfer and heat transfer efficiency by the loop reactor structure, can improve production efficiency, and is suitable for industrial scale production.

Description

Nitration reaction system

Technical Field

The application relates to the technical field of chemical equipment, in particular to a nitration reaction system.

Background

The nitration reaction belongs to one of dangerous production processes, has higher reaction risk, is still used by most enterprises at present by using an intermittent kettle or continuous kettle type nitration process, has large production equipment volume, large online nitration material storage capacity, poor heat transfer capability and low production efficiency, and is urgent for the improvement of nitration reaction equipment.

Disclosure of Invention

In view of the above, the application provides a nitration reaction system to solve the problems of large volume, large online nitration material storage capacity, poor heat transfer capability and low production efficiency of the existing nitration reaction equipment.

The application provides a nitration reaction system which comprises a loop reactor and an acid phase separator. Wherein the loop reactor comprises at least one combination of a non-circulating reactor and a circulating pump, the outlet of the circulating pump is communicated with the inlet of the non-circulating reactor, and the inlet of the circulating pump is communicated with the outlet of the non-circulating reactor; or the loop reactor is a loop reactor; the acid phase separator is suitable for separating acid phase, and the inlet of the acid phase separator is communicated with the reaction liquid outlet of the circulation reactor of the final stage.

In an alternative embodiment, the nitration reaction system further comprises an acid phase temporary storage tank, an inlet of the acid phase temporary storage tank is communicated with an outlet of the acid phase separator, and an outlet of the acid phase temporary storage tank is communicated with an acid phase inlet of the loop reactor of any stage through a transfer pump.

In an alternative embodiment, the nitration reaction system further comprises an acid phase concentrating unit, the acid phase separator having a first acid phase outlet and a second acid phase outlet, the first acid phase outlet being in communication with the acid phase inlet of the loop reactor of either stage via a transfer pump, the second acid phase outlet being in communication with the inlet of the acid phase concentrating unit.

In an alternative embodiment, the nitration reaction system further comprises an acid phase temporary storage tank; the outlet of the acid phase separator is communicated with the inlet of the acid phase concentrating unit, the outlet of the acid phase concentrating unit is communicated with the inlet of the acid phase temporary storage tank, and the outlet of the acid phase temporary storage tank is communicated with the acid phase inlet of the loop reactor of any stage through the transfer pump; or the acid phase separator is provided with a first acid phase outlet and a second acid phase outlet, the first acid phase outlet is communicated with the acid phase inlet of the loop reactor of any stage through the transfer pump, the second acid phase outlet is communicated with the inlet of the acid phase concentrating unit, the outlet of the acid phase concentrating unit is communicated with the inlet of the acid phase temporary storage tank, and the outlet of the acid phase temporary storage tank is communicated with the acid phase inlet of the loop reactor of any stage through the transfer pump.

In an alternative embodiment, the nitration reaction system further comprises a delay device, an inlet of the delay device being in communication with an outlet of the loop reactor of the final stage, an outlet of the delay device being in communication with an inlet of the acid phase separator.

In an alternative embodiment, the nitration reaction system further comprises a material conveying device comprising a raw material conveying device and an acid phase conveying device, the discharge port of the raw material conveying device being in communication with the raw material inlet of the loop reactor of the first stage, the discharge port of the acid phase conveying device being in communication with the acid phase inlet of the loop reactor of the first stage.

In an alternative embodiment, the nitration reaction system further comprises a mixing apparatus; the feed inlet of the mixing device is communicated with the discharge outlet of the material conveying device, and the discharge outlet of the mixing device is communicated with the inlet of the first-stage loop reactor; or the feed inlet of the mixing device is communicated with the discharge outlet of the material conveying device and the reaction liquid outlet of the loop reactor of any stage, and the discharge outlet of the mixing device is communicated with the material inlet of the loop reactor of the first stage.

In an alternative embodiment, the feed inlet of the mixing device is in communication with the reaction liquid outlet of the loop reactor of any stage and the acid outlet of the acid phase separator, and the discharge outlet of the mixing device is in communication with the feed inlet of the loop reactor of any stage.

In an alternative embodiment, the nitration reaction system further comprises at least one pre-heat exchange apparatus; the inlet of the pre-heat exchange equipment is communicated with the discharge port of the material conveying equipment, and the outlet of the pre-heat exchange equipment is communicated with the inlet of the first-stage loop reactor; or the inlet of the pre-heat exchange equipment is communicated with the outlet of the acid phase separator, and the outlet of the pre-heat exchange equipment is communicated with the inlet of any stage of loop reactor. In an alternative embodiment, the loop reactor is a loop reactor, and the loop reactor is an annular loop reactor formed by a transmission device, a stirring shaft provided with axial flow blades, a fluid distributor and a heat exchanger, wherein the transmission device drives the stirring shaft to rotate.

The beneficial effects are that:

The nitration reaction system provided by the application adopts the acid phase separator and the circulation reactor, can realize continuous feeding, continuous reaction, continuous discharging and separation of an acid phase and an organic phase containing a product, can realize full-automatic control in the whole process, realizes unmanned management, is simple to operate, reduces labor cost, ensures personal safety, ensures low online quantity of nitration materials in the whole reaction system, ensures higher mass transfer and heat transfer efficiency due to the circulation reactor structure, ensures intrinsic safety of the reaction process, can improve production efficiency and can be applied to industrial-scale production.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present application, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

Description of the drawings:

FIG. 1 is a schematic diagram of a first configuration of a nitration reaction system according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a second configuration of a nitration reaction system according to an embodiment of the present application;

FIG. 3 is a schematic diagram of a third configuration of a nitration reaction system according to an embodiment of the present application;

FIG. 4 is a schematic diagram of a fourth configuration of a nitration reaction system according to an embodiment of the present application;

FIG. 5 is a schematic view of a fifth embodiment of a nitration reaction system according to the present application;

FIG. 6 is a schematic view showing a sixth configuration of a nitration reaction system according to an embodiment of the present application;

FIG. 7 is a schematic view of a seventh configuration of a nitration reaction system according to an embodiment of the present application;

FIG. 8 is a schematic view of an eighth configuration of a nitration reaction system according to an embodiment of the present application;

FIG. 9 is a schematic diagram of a ninth configuration of a nitration reaction system according to an embodiment of the present application;

FIG. 10 is a schematic view of a tenth construction of a nitration reaction system according to an embodiment of the present application;

FIG. 11 is a schematic view showing an eleventh construction of the nitration reaction system according to the embodiment of the application.

Reference numerals illustrate:

1. A loop reactor;

A. A first stage loop reactor; a-1, a first circulating pump; a-2, a first primary reaction device; a-3, a first secondary reaction device; a-4, a first transmission device; a-5, a first stirring shaft; a-6, a first fluid distributor; a-7, a first heat exchanger;

B. a second stage loop reactor; b-1, a second circulating pump; b-2, second-stage reaction equipment; b-3, second-stage reaction equipment; b-4, a second transmission device; b-5, a second stirring shaft; b-6, a second fluid distributor; b-7, a second heat exchanger;

C. A third stage loop reactor; c-1, a third circulating pump; c-2, third-stage reaction equipment;

2. an acid phase separator; 3. an acid phase temporary storage tank; 4. a transfer pump;

4-1, a first transfer pump; 4-2, a second transfer pump;

5. an acid phase concentrating unit; 6. a delay device; 7. a material conveying device;

7-1, raw material conveying equipment; 7-2, acid phase conveying equipment;

8. a mixing device;

8-1, a first mixing device; 8-2, a second mixing device;

9. A pre-heat exchange device;

9-1, a first pre-heat exchange device; 9-2, a second pre-heat exchange device; 9-3, a third pre-heat exchange device.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

Referring to fig. 1, the present application provides a nitration reaction system comprising a loop reactor 1 and an acid phase separator 2. Wherein the loop reactor 1 comprises at least one combination of a non-circulating reactor and a circulating pump, the outlet of the circulating pump is communicated with the inlet of the non-circulating reactor, and the inlet of the circulating pump is communicated with the outlet of the non-circulating reactor; or the loop reactor is a loop reactor; the acid phase separator 2 is suitable for separating acid phase, and the inlet of the acid phase separator 2 is communicated with the reaction liquid outlet of the final circulation reactor 1.

Preferably, the loop reactor 1 has multiple stages in series in sequence.

Specifically, the nitration reaction system provided by the application adopts the acid phase separator 2 and the loop reactor 1 which are sequentially connected in series, so that continuous feeding, continuous reaction, continuous discharging and separation of an acid phase and an organic phase containing a product can be realized, full-automatic control can be realized in the whole process, unmanned management is realized, the operation is simple, the labor cost is reduced, the personal safety is ensured, the online quantity of nitration materials in the whole reaction system is low, the loop reactor structure ensures higher mass transfer and heat transfer efficiency, the intrinsic safety of the reaction process is ensured, the production efficiency can be improved, and the nitration reaction system can be applied to industrial scale production.

In particular, the acid phase separator 2 is selected from a solid-liquid separator or a liquid-liquid separator; the corresponding separator is selected according to the state of the materials in the nitration reaction liquid, namely, when the nitration reaction liquid is in a solid-liquid two-phase state, the solid-liquid separator is selected, and when the nitration reaction liquid is in a liquid-liquid heterogeneous state, the liquid-liquid separator is selected, and the separated water phase is the acid phase.

In some embodiments, referring to fig. 2, the nitration reaction system further comprises an acid phase temporary storage tank 3, an inlet of the acid phase temporary storage tank 3 is communicated with an outlet of the acid phase separator 2, and an outlet of the acid phase temporary storage tank 3 is communicated with an acid phase inlet of the loop reactor 1 of any stage through a transfer pump 4.

Specifically, the outlet of the acid phase separator 2 is communicated with the inlet of the acid phase temporary storage tank 3, the outlet of the acid phase temporary storage tank 3 is communicated with the acid phase inlet of the loop reactor 1 of any stage through the transfer pump 4, and part of the acid phase separated by the acid phase separator 2 is returned to the loop reactor 1 of any stage through the transfer pump 4.

Further, the acid phase separated by the acid phase separator 2 is recycled, so that the treatment cost of the acid is reduced, the utilization rate of the acid is improved, and the acid cost is saved; moreover, the acid phase temporary storage tank 3 can wait for the acid adding time, so that the situation that the acid quantity in the loop reactor 1 is too much due to direct acid adding is avoided, the reaction is too violent, and the acid phase temporary storage tank can be used for supplementing when the acid quantity in the loop reactor 1 is smaller, so that the reaction rate is improved, and the production rhythm is controlled.

In some embodiments, referring to fig. 3, the nitration reaction system further comprises an acid phase enrichment unit 5, the acid phase separator 2 having a first acid phase outlet in communication with the acid phase inlet of the loop reactor 1 of either stage via a transfer pump 4 and a second acid phase outlet in communication with the inlet of the acid phase enrichment unit 5.

Specifically, the acid phase separator 2 can separate and purify the nitration reaction liquid for a plurality of times, the concentrated acid which is primarily separated can be directly recycled, then the separated dilute acid is concentrated by the acid phase concentrating unit 5 to increase the concentration, and then the dilute acid is recycled, so that the utilization rate of the acid is further improved, the acid cost is saved, and the treatment cost of the waste acid is reduced.

In some embodiments, referring to fig. 4 and 5, the nitration reaction system further includes an acid phase temporary storage tank 3. The outlet of the acid phase separator 2 is communicated with the inlet of the acid phase concentrating unit 5, the outlet of the acid phase concentrating unit 5 is communicated with the inlet of the acid phase temporary storage tank 3, and the outlet of the acid phase temporary storage tank 3 is communicated with the acid phase inlet of the loop reactor 1 of any stage through the transfer pump 4; or the acid phase separator 2 is provided with a first acid phase outlet and a second acid phase outlet, the first acid phase outlet is communicated with the acid phase inlet of the loop reactor 1 of any stage through the transfer pump 4, the second acid phase outlet is communicated with the inlet of the acid phase concentrating unit 5, the outlet of the acid phase concentrating unit 5 is communicated with the inlet of the acid phase temporary storage tank 3, and the outlet of the acid phase temporary storage tank 3 is communicated with the acid phase inlet of the loop reactor 1 of any stage through the transfer pump 4.

Specifically, the present solution proposes two parallel embodiments, and the present solution and the above solution also constitute parallel embodiments.

Specifically, the acid phase concentrating unit 5 is one or a combination of a distillation still and a rectification tower, when the acid phase is nitric acid with lower concentration, the acid phase concentrating unit 5 can be a distillation still or a rectification tower, and when the acid phase is nitric acid or sulfuric acid with higher concentration, the acid phase concentrating unit 5 is a combination of a distillation still and a rectification tower.

In some embodiments, referring to fig. 6, the nitration reaction system further comprises a delay apparatus 6, an inlet of the delay apparatus 6 being in communication with an outlet of the loop reactor 1 of the final stage, an outlet of the delay apparatus 6 being in communication with an inlet of the acid phase separator 2.

Specifically, the scheme is that a delay device 6 is arranged at the rear end of the loop reactor 1 and is used for prolonging the reaction time of materials, improving the conversion rate of raw materials and reducing the residual materials in the products.

In particular, the delay device 6 is selected from one of a dynamic tubular reactor, a static tubular reactor and a microchannel reactor.

In some embodiments, referring to fig. 6-11, the nitration reaction system further comprises a material transfer apparatus 7, the material transfer apparatus 7 comprising a raw material transfer apparatus 7-1 and an acid phase transfer apparatus 7-2, a discharge port of the raw material transfer apparatus 7-1 being in communication with a raw material inlet of the loop reactor 1 of the first stage and a discharge port of the acid phase transfer apparatus 7-2 being in communication with an acid phase inlet of the loop reactor 1 of the first stage.

In particular, the raw material transporting apparatus 7-1 is selected from at least one of a diaphragm pump, a centrifugal pump, a gear pump, a plunger pump, a screw pump, a slurry pump, and a solid feeder, and is selected according to the state of the raw material.

The acid phase transporting device 7-2 is at least one selected from the group consisting of a diaphragm pump, a centrifugal pump, a gear pump, a plunger pump, and a screw pump.

In some embodiments, referring to fig. 7-9 and 11, the nitration reaction system further comprises a mixing apparatus 8. The feed inlet of the mixing device 8 is communicated with the discharge outlet of the material conveying device 7, and the discharge outlet of the mixing device 8 is communicated with the inlet of the first-stage loop reactor 1; or the feed inlet of the mixing device 8 is communicated with the discharge outlet of the material conveying device 7 and the reaction liquid outlet of the first-stage loop reactor 1, and the discharge outlet of the mixing device 8 is communicated with the material inlet of the first-stage loop reactor 1.

In some embodiments, the feed inlet of the mixing device 8 is in communication with the reaction liquid outlet of the loop reactor 1 of any stage and the outlet of the acid phase separator 2, and the discharge outlet of the mixing device 8 is in communication with the feed inlet of the loop reactor 1 of any stage.

Specifically, the above two schemes provide three parallel embodiments, and the mixing device 8 pre-mixes the materials before entering the loop reactor 1, so that the materials participating in the nitration reaction are mixed more uniformly and the reaction is more complete.

More specifically, in one embodiment, the feed inlet of the mixing device 8 is in communication with the discharge outlet of the material conveying device 7, the discharge outlet of the mixing device 8 is in communication with the material inlet of the loop reactor 1 of the first stage for premixing the raw material with the acid phase material. In one embodiment, the feed inlet of the mixing device 8 is in communication with the discharge outlet of the material handling device 7 and the outlet of the circulation pump, the discharge outlet of the mixing device 8 is in communication with the inlet of the loop reactor 1 of the first stage for mixing the raw material with the acid phase material and the circulating material. In one embodiment, the feed inlet of the mixing device 8 is in communication with the material outlet of the loop reactor 1 of any stage and the outlet of the transfer pump 4, and the discharge outlet of the mixing device 8 is in communication with the material inlet of the loop reactor 1 of any stage for mixing the recycled material with the recovered acid phase material.

In particular, the mixing device 8 is selected from one of a static mixer, a dynamic tubular reactor and a microchannel reactor.

As shown in fig. 8, the mixing device 8 includes, but is not limited to, a first mixing device 8-1 and a second mixing device 8-2.

In some embodiments, referring to fig. 10 and 11, the nitration reaction system further comprises at least one pre-heat exchange apparatus 9. The inlet of the pre-heat exchange equipment 9 is communicated with the discharge port of the material conveying equipment 7, and the outlet of the pre-heat exchange equipment 9 is communicated with the inlet of the first-stage loop reactor 1; or the inlet of the pre-heat exchange equipment 9 is communicated with the outlet of the acid phase separator 2, and the outlet of the pre-heat exchange equipment 9 is communicated with the inlet of the loop reactor 1 of any stage.

Specifically, the scheme provides two parallel embodiments, in one embodiment, a feed inlet of the pre-heat exchange device 9 is communicated with a discharge outlet of the material conveying device 7, and the discharge outlet of the pre-heat exchange device 9 is communicated with an inlet of the first-stage loop reactor 1 and is used for preheating or precooling a raw material or an acid phase material. In one embodiment, the feed inlet of the pre-heat exchange device 9 is communicated with the outlet of the transfer pump 4, and the discharge outlet of the pre-heat exchange device 9 is communicated with the inlet of any stage of loop reactor 1 for heating or cooling the recovered acid phase material.

In particular, the pre-heat exchange device 9 is selected from a tubular heat exchanger or a plate heat exchanger.

It should be noted that, as shown in fig. 10, the pre-heat exchanging device 9 includes, but is not limited to, a first pre-heat exchanging device 9-1, a second pre-heat exchanging device 9-2, and a third pre-heat exchanging device 9-3.

In some embodiments, referring to fig. 1, 2, 4-6 and 8-10, the loop reactor 1 comprises at least one non-circulating reactor and at least one circulating pump, the outlet of the circulating pump being in communication with the inlet of the non-circulating reactor, the inlet of the circulating pump being in communication with the outlet of the non-circulating reactor.

In particular, the present solution is an alternative embodiment of the loop reactor 1.

In particular, the reaction apparatus is selected from the group consisting of one or more of a dynamic tubular reactor, a static tubular reactor and a microchannel reactor. In order to increase the throughput of the reaction system or in the case of solid materials involved, the reaction apparatus is preferably a dynamic tubular reactor.

In addition, the circulation pump is selected from one or more of a centrifugal pump, a screw pump, a gear pump, an emulsion pump, a rotor pump, and an axial flow pump.

In some embodiments, referring to fig. 3, 7 and 11, the loop reactor 1 is a loop reactor, which is a loop reactor consisting of a transmission device, a stirring shaft equipped with axial flow blades, a fluid distributor and a heat exchanger, wherein the transmission device drives the stirring shaft to rotate.

Specifically, the scheme is another alternative embodiment of the loop reactor 1, the transmission device drives the stirring shaft to rotate, axial flow paddles on the stirring shaft generate downward axial force on materials, the materials enter the heat exchanger through the fluid distributor under the action of the axial force and circularly flow in the loop, and a raw material inlet and an acid phase inlet of the loop reactor 1 can be arranged at any position of the loop reactor 1; preferably, the raw material inlet and the acid phase inlet are arranged at the inlet end of the chamber where the stirring shaft is arranged or the flow direction front end of the fluid distributor, and the reaction liquid outlet of the loop reactor 1 is arranged at the outlet end of the heat exchanger.

Wherein the fluid distributor is used to enhance the mass transfer effect of the loop reactor 1.

In particular, the heat exchanger is selected from a shell and tube heat exchanger or a coiled tube heat exchanger.

More specifically, as shown in fig. 1 to 11, the loop reactor 1 may include, but is not limited to, a first stage loop reactor a, a second stage loop reactor B, and a third stage loop reactor C. Wherein the first stage loop reactor A includes, but is not limited to, a first circulation pump A-1, a first primary reaction device A-2, and a first secondary reaction device A-3; or comprises a first transmission device A-4, a first stirring shaft A-5, a first fluid distributor A-6 and a first heat exchanger A-7. The second-stage loop reactor B comprises, but is not limited to, a second circulating pump B-1, a second first-stage reaction device B-2 and a second-stage reaction device B-3; or comprises a second transmission device B-4, a second stirring shaft B-5, a second fluid distributor B-6 and a second heat exchanger B-7. The third stage loop reactor C includes, but is not limited to, a third circulation pump C-1 and a third stage reaction apparatus C-2.

In the present application, unless explicitly specified or defined otherwise, the manner of communication between units or devices should be construed broadly. For example, the pipeline communication can be direct pipeline communication, or pipeline communication through conventional conveying, metering, controlling and temporary storage equipment such as pumping equipment, metering equipment, valve pipe fittings, intermediate tanks and the like, or fixed communication or detachable communication. The specific meaning of the above terms in the present application can be understood by those skilled in the art according to the specific circumstances.

In the present application, various components of the reaction apparatus, such as a microchannel reactor, a heat exchanger, a circulating pump, a dynamic tube reactor, a solid-liquid separator, a liquid-liquid separator, etc., are commercially available, but the entire reaction apparatus is not commercially available nor known to those skilled in the art.

Claims

1. A nitration reaction system, comprising:

A loop reactor (1) comprising a combination of at least one non-loop reactor and a circulation pump, the outlet of the circulation pump being in communication with the inlet of the non-loop reactor, the inlet of the circulation pump being in communication with the outlet of the non-loop reactor; or the loop reactor (1) is a loop reactor;

An acid phase separator (2) adapted to separate an acid phase, an inlet of said acid phase separator (2) being in communication with a reaction liquid outlet of said loop reactor (1) of the final stage.

2. The nitration reaction system according to claim 1, further comprising an acid phase temporary storage tank (3);

The inlet of the acid phase temporary storage tank (3) is communicated with the acid phase outlet of the acid phase separator (2), and the outlet of the acid phase temporary storage tank (3) is communicated with the acid phase inlet of the loop reactor (1) of any stage through a transfer pump (4).

3. The nitration reaction system according to claim 1, further comprising an acid phase enrichment unit (5);

The acid phase separator (2) is provided with a first acid phase outlet and a second acid phase outlet, the first acid phase outlet is communicated with an acid phase inlet of the loop reactor (1) of any stage through a transfer pump (4), and the second acid phase outlet is communicated with an inlet of the acid phase concentration unit (5).

4. A nitration reaction system according to claim 3, characterised in that it further comprises an acid phase temporary storage tank (3);

The acid phase outlet of the acid phase separator (2) is communicated with the inlet of the acid phase concentrating unit (5), the outlet of the acid phase concentrating unit (5) is communicated with the inlet of the acid phase temporary storage tank (3), and the outlet of the acid phase temporary storage tank (3) is communicated with the acid phase inlet of the loop reactor (1) of any stage through a transfer pump (4);

Or the acid phase separator (2) is provided with a first acid phase outlet and a second acid phase outlet, the first acid phase outlet is communicated with an acid phase inlet of the loop reactor (1) of any stage through a transfer pump (4), the second acid phase outlet is communicated with an inlet of the acid phase concentrating unit (5), an outlet of the acid phase concentrating unit (5) is communicated with an inlet of the acid phase temporary storage tank (3), and an outlet of the acid phase temporary storage tank (3) is communicated with an acid phase inlet of the loop reactor (1) of any stage through the transfer pump (4).

5. The nitration reaction system according to claim 1, further comprising a time delay device (6); the inlet of the delay device (6) is communicated with the outlet of the loop reactor (1) of the final stage, and the outlet of the delay device (6) is communicated with the inlet of the acid phase separator (2).

6. The nitration reaction system according to claim 1, further comprising a material conveying device (7);

The material conveying equipment (7) comprises raw material conveying equipment (7-1) and acid phase conveying equipment (7-2), a discharge port of the raw material conveying equipment (7-1) is communicated with a raw material inlet of the loop reactor (1) of the first stage, and a discharge port of the acid phase conveying equipment (7-2) is communicated with an acid inlet of the loop reactor (1) of the first stage.

7. The nitration reaction system according to claim 6, further comprising a mixing apparatus (8);

The feed inlet of the mixing device (8) is communicated with the discharge outlet of the material conveying device (7), and the discharge outlet of the mixing device (8) is communicated with the material inlet of the loop reactor (1) of the first stage;

Or the feed inlet of the mixing device (8) is communicated with the discharge outlet of the material conveying device (7) and the reaction liquid outlet of the loop reactor (1) of any stage, and the discharge outlet of the mixing device (8) is communicated with the material inlet of the loop reactor (1) of the first stage.

8. The nitration reaction system according to claim 6, further comprising a mixing apparatus (8); the feed inlet of the mixing device (8) is communicated with the reaction liquid outlet of the loop reactor (1) of any stage and the acid phase outlet of the acid phase separator (2), and the discharge outlet of the mixing device (8) is communicated with the material inlet of the loop reactor (1) of any stage.

9. The nitration reaction system according to claim 6, further comprising a pre-heat exchange device (9);

The inlet of the pre-heat exchange equipment (9) is communicated with the discharge port of the material conveying equipment (7), and the outlet of the pre-heat exchange equipment (9) is communicated with the material inlet of the loop reactor (1) of the first stage;

or the inlet of the pre-heat exchange equipment (9) is communicated with the outlet of the acid phase separator (2), and the outlet of the pre-heat exchange equipment (9) is communicated with the material inlet of the loop reactor (1) of any stage.

10. The nitration reaction system according to any of claims 1 to 9, wherein the circulation reactor is a loop reactor comprising a transmission, a stirring shaft fitted with axial flow paddles, a fluid distributor and a heat exchanger, the transmission driving the stirring shaft in rotation.