A crystalline diammonium phosphate neutralization system

Abstract

The utility model relates to the technical field of chemical production, and specifically, provides a crystalline ammonium dihydrogen phosphate neutralization system, comprising a primary neutralization tower and a secondary neutralization tower which are connected in sequence, wherein a primary reactor is arranged in the primary neutralization tower, and a first discharge pipe is arranged at the discharge end of the primary reactor; the first discharge pipe is connected to the secondary neutralization tower; the secondary neutralization tower comprises a secondary reactor, a tertiary reactor, and a circulation pump; the secondary reactor is arranged in the secondary neutralization tower and the secondary reactor is connected to the first discharge pipe; a second discharge pipe is arranged at the bottom of the secondary neutralization tower, and a discharge branch pipe is connected to one side of the second discharge pipe; the circulation pump is arranged at the discharge end of the second discharge pipe, and the circulation pump is connected to a third discharge pipe, and the discharge end of the third discharge pipe is connected to the secondary neutralization tower; one side of the third discharge pipe is connected to a tertiary reactor for conveying liquid nitrogen, which can make the reaction of ammonia and phosphoric acid more complete and sufficient, and the installation and connection between the components of the neutralization system are more stable and reliable.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical production, in particular to a crystalline diammonium phosphate neutralization system. Background Art

[0002] In the actual production process of crystalline ammonium dihydrogen phosphate, due to the problems of neutralization reaction process and ammonia passing rate, since the existing technology basically introduces ammonia slowly at one time to mix with phosphoric acid, the reaction between ammonia and phosphoric acid is not thorough, which eventually leads to unstable slurry concentration, specific gravity, and neutralization degree, and finally causes pipeline blockage, severe vibration of the circulation pipe and reactor, and even frequent ammonia leakage, resulting in frequent shutdown of the device and long-term low-load operation. Not only does it affect the production capacity of the device, but it also affects the stability of subsequent crystallization. Utility Model Content

[0003] The utility model aims to provide a crystalline diammonium phosphate neutralization system, which can make the reaction between ammonia and phosphoric acid more complete and sufficient, and the installation and connection between the components of the neutralization system are more stable and reliable.

[0004] The embodiments of the present invention are implemented by the following technical solutions:

[0005] A crystalline diammonium phosphate neutralization system comprises a primary neutralization tower and a secondary neutralization tower which are connected in sequence.

[0006] A first reactor is arranged in the first neutralization tower, and a first discharge pipe is provided at the discharge end of the first reactor; liquid ammonia and phosphoric acid are fed into the first reactor through a feed pipe to react to obtain reaction slurry, and the reaction slurry is fed into the second neutralization tower through the first discharge pipe;

[0007] The secondary neutralization tower comprises a secondary reactor, a tertiary reactor, and a circulation pump; the secondary reactor is arranged inside the secondary neutralization tower, and the feed end of the secondary reactor is connected to the discharge end of the first discharge pipe; a second discharge pipe is arranged at the bottom of the secondary neutralization tower, and one side of the second discharge pipe is connected to a discharge branch pipe; the circulation pump is arranged at the discharge end of the second discharge pipe, and the circulation pump is connected to a third discharge pipe, and the discharge end of the third discharge pipe is connected to the secondary neutralization tower; one side of the third discharge pipe is connected to a tertiary reactor for conveying liquid nitrogen;

[0008] The reaction slurry is sent to the circulation pump through the second discharge pipe and enters the tertiary reactor with liquid nitrogen. Then the reaction slurry is sent to the secondary neutralization tower through the third discharge pipe, and the mixed material is taken out through the discharge branch pipe on the side wall of the second discharge pipe.

[0009] Furthermore, the secondary neutralization tower further comprises a heat exchanger, and the heat exchanger is arranged between the discharge end of the third discharge pipe and the secondary neutralization tower.

[0010] Furthermore, a circulation pipe is connected to the discharge end of the heat exchanger, and the circulation pipe extends into the secondary neutralization tower; the nozzle of the secondary reactor is located below the nozzle of the circulation pipe.

[0011] Furthermore, an expansion joint is provided at the connection between the feed pipe and the primary reactor.

[0012] Furthermore, the primary reactor is spirally arranged in an S shape inside the primary neutralization tower.

[0013] The technical solution of the embodiment of the utility model has at least the following advantages and beneficial effects:

[0014] The utility model has reasonable design and simple structure. Liquid ammonia and phosphoric acid are sent into a primary reactor through a feed pipe for a primary ammoniation reaction, and then the reaction slurry is sent into a secondary neutralization tower through a first discharge pipe of the primary reactor. The reaction slurry is first sent to a circulation pump through a second discharge pipe of the secondary neutralization tower and mixed with liquid nitrogen for a secondary ammoniation reaction, and then sent into the secondary neutralization tower to be mixed with the reaction slurry entering the secondary neutralization tower; the mixed material is extracted through a discharge branch pipe on the side wall of the second discharge pipe; it is beneficial to complete and sufficient ammoniation reaction of the reaction slurry, and ensures a constant concentration of the circulating crystal slurry; more importantly, compared with the existing treatment system, the neutralization system of the utility model has less modification, less investment, and obvious reaction effect; the equipment is simple, easy to install and implement, low investment, simple operation, and practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model 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 paying creative work.

[0016] Figure 1 A flow chart of a crystalline diammonium phosphate neutralization system provided in an embodiment of the utility model;

[0017] Icons: 1-primary neutralization tower, 2-feed pipe, 3-primary reactor, 4-first discharge pipe, 5-secondary reactor, 6-secondary neutralization tower, 7-circulation pipe, 8-second discharge pipe, 9-circulation pump, 10-third discharge pipe, 11-tertiary reactor, 12-heat exchanger, 13-discharge branch pipe. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0019] Example 1

[0020] A crystalline ammonium dihydrogen phosphate neutralization system comprises a primary neutralization tower 1 and a secondary neutralization tower 6 which are connected in sequence, wherein a primary reactor 3 is arranged in the primary neutralization tower 1, and a first discharge pipe 4 is provided at the discharge end of the primary reactor 3; liquid ammonia and phosphoric acid are fed into the primary reactor 3 through a feed pipe 2 to react to obtain a reaction slurry, and the reaction slurry is fed into the secondary neutralization tower 6 through the first discharge pipe 4;

[0021] The secondary neutralization tower 6 comprises a secondary reactor 5, a tertiary reactor 11, and a circulation pump 9; the secondary reactor 5 is arranged inside the secondary neutralization tower 6, and the feed end of the secondary reactor 5 is connected to the discharge end of the first discharge pipe 4; a second discharge pipe 8 is arranged at the bottom of the secondary neutralization tower 6, and a discharge branch pipe 13 is connected to one side of the second discharge pipe 8; the circulation pump 9 is arranged at the discharge end of the second discharge pipe 8, and the circulation pump 9 is connected to the third discharge pipe 10, and the discharge end of the third discharge pipe 10 is connected to the secondary neutralization tower 6; one side of the third discharge pipe 10 is connected to the tertiary reactor 11 for conveying liquid nitrogen;

[0022] The reaction slurry is sent to the circulation pump 9 through the second discharge pipe 8 and enters the tertiary reactor 11 with liquid nitrogen. Then the reaction slurry is sent to the secondary neutralization tower 6 through the third discharge pipe 10. The mixed material is produced through the discharge branch pipe 13 on the side wall of the second discharge pipe 8. Preferably, a production pump can also be provided on the discharge branch pipe 13.

[0023] In this embodiment, the secondary neutralization tower 6 further includes a heat exchanger 12, which is arranged between the discharge end of the third discharge pipe 10 and the secondary neutralization tower 6; so that heat exchange can be performed when the reaction slurry and liquid nitrogen undergo secondary amination reaction, and the reaction is more sufficient and thorough.

[0024] In this embodiment, the discharge end of the heat exchanger 12 is connected to a circulation pipe 7, and the circulation pipe 7 extends into the secondary neutralization tower 6; the nozzle of the secondary reactor 5 is located below the nozzle of the circulation pipe 7, which is conducive to the complete and sufficient amination reaction of the reaction slurry; specifically in this embodiment, the secondary reactor 5 can be set to a tubular structure.

[0025] In this embodiment, an expansion joint is provided at the connection between the feed pipe 2 of the primary reactor 3 and the primary reactor 3, thereby achieving a certain vibration reduction effect and making the reaction more stable and reliable.

[0026] In this embodiment, one side of the third discharge pipe 10 between the discharge port of the circulation pump 9 and the heat exchanger 12 is connected to a tertiary reactor 11 for conveying liquid nitrogen, so as to facilitate rapid mixing of liquid ammonia with the reaction slurry and enter the heat exchanger 12 together for a thorough heat exchange reaction; specifically, in this embodiment, the tertiary reactor 11 can be configured as a tubular structure.

[0027] In this embodiment, the primary reactor 3 is spirally arranged in an S shape in the primary neutralization tower 1, so that the flow path between the liquid ammonia and the phosphoric acid is longer, thereby making the reaction between the liquid ammonia and the phosphoric acid more thorough.

[0028] Working principle: The utility model utilizes a primary neutralization tower 1 and a secondary neutralization tower 6 to carry out two-stage ammonia flow and two-stage reaction; the primary reaction and the primary ammonia flow are carried out in the primary neutralization tower 1. Specifically, liquid ammonia and phosphoric acid are sent to the primary reactor 3 through the feed pipe 2 for primary amination reaction, and then the reaction slurry is sent to the secondary neutralization tower 6 through the first discharge pipe 4 of the primary reactor 3. The reaction slurry is first sent to the circulation pump 9 through the second discharge pipe 8 of the secondary neutralization tower 6 and mixed with the liquid nitrogen in the tertiary reactor 11 for secondary amination reaction, and then sent to the secondary neutralization tower through the third discharge pipe 10. Tower 6, mixed with the reaction slurry entering the secondary neutralization tower 6; preferably, a heat exchanger 12 is also provided before entering the secondary neutralization tower 6, so that the material can be heat exchanged, which is conducive to a more thorough reaction; the mixed material is taken out through the discharge branch pipe 13 on the side wall of the second discharge pipe 8; it is conducive to the complete and sufficient amination reaction of the reaction slurry, ensuring the constant concentration of the circulating crystal slurry; more importantly, compared with the existing treatment system, the neutralization system of the utility model has less modification, less investment, and obvious reaction effect; the equipment is simple, easy to install and implement, low investment, simple operation, and practical.

[0029] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A crystalline diammonium phosphate neutralization system, characterized in that: It includes a primary neutralization tower and a secondary neutralization tower which are connected in sequence. A first reactor is arranged in the first neutralization tower, and a first discharge pipe is provided at the discharge end of the first reactor; liquid ammonia and phosphoric acid are fed into the first reactor through a feed pipe to react to obtain reaction slurry, and the reaction slurry is fed into the second neutralization tower through the first discharge pipe; The secondary neutralization tower comprises a secondary reactor, a tertiary reactor, and a circulation pump; the secondary reactor is arranged inside the secondary neutralization tower, and the feed end of the secondary reactor is connected to the discharge end of the first discharge pipe; a second discharge pipe is arranged at the bottom of the secondary neutralization tower, and one side of the second discharge pipe is connected to a discharge branch pipe; the circulation pump is arranged at the discharge end of the second discharge pipe, and the circulation pump is connected to a third discharge pipe, and the discharge end of the third discharge pipe is connected to the secondary neutralization tower; one side of the third discharge pipe is connected to a tertiary reactor for conveying liquid nitrogen; The reaction slurry is sent to the circulation pump through the second discharge pipe and enters the tertiary reactor with liquid nitrogen. Then the reaction slurry is sent to the secondary neutralization tower through the third discharge pipe, and the mixed material is taken out through the discharge branch pipe on the side wall of the second discharge pipe.

2. The crystalline diammonium phosphate neutralization system according to claim 1, characterized in that: The secondary neutralization tower further comprises a heat exchanger, and the heat exchanger is arranged between the discharge end of the third discharge pipe and the secondary neutralization tower.

3. The crystalline diammonium phosphate neutralization system according to claim 2, characterized in that: The discharge end of the heat exchanger is connected with a circulation pipe, and the circulation pipe extends into the secondary neutralization tower; the nozzle of the secondary reactor is located below the nozzle of the circulation pipe.

4. The crystalline ammonium dihydrogen phosphate neutralization system according to claim 1, characterized in that: An expansion joint is provided at the connection between the feed pipe and the primary reactor.

5. The crystalline ammonium dihydrogen phosphate neutralization system according to claim 1, characterized in that: The primary reactor is spirally arranged in an S shape inside the primary neutralization tower.

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