Device for stably conveying phosphoric acid to production line by using waste heat of production line

Abstract

The utility model discloses a device for stably conveying phosphoric acid to a production line by using waste heat of the production line, which is used for conveying 85% phosphoric acid in ammonium polyphosphate production and comprises a first phosphoric acid storage tank and a second phosphoric acid storage tank, the bottom of the first phosphoric acid storage tank is connected with a first acid discharge pipe, and the bottom of the second phosphoric acid storage tank is connected with a second acid discharge pipe. The device for stably conveying phosphoric acid to the production line by using the waste heat of the production line further comprises a constant-temperature hot water tank, a production line waste heat fluid pipeline and a phosphoric acid main pipe, the first acid discharge pipe and the second acid discharge pipe are respectively communicated with the phosphoric acid main pipe, and the production line waste heat fluid pipeline is connected with the constant-temperature hot water tank. A first hot water heating jacket is arranged outside the tank bottom of the first phosphoric acid storage tank, a second hot water heating jacket is arranged outside the tank bottom of the second phosphoric acid storage tank, the phosphoric acid conveying device further comprises a heat preservation water pipe and a heat preservation water return pipe, and a first pump is installed on the heat preservation water pipe; the heat preservation water pipe is communicated with the first hot water heating jacket, the second hot water heating jacket and the constant-temperature hot water tank, the heat preservation water return pipe is communicated with the first hot water heating jacket, the second hot water heating jacket and the constant-temperature hot water tank, a second pump is installed on the output section of the phosphoric acid main pipe, and an outlet of the second pump is connected with a production line use conveying pipe. The phosphoric acid conveying device can stably convey 85% phosphoric acid to a production line.

Description

Technical Field

[0001] The utility model relates to the production of ammonium polyphosphate, and particularly to a device for stably transporting phosphoric acid to a production line by using the waste heat of the production line. Background Art

[0002] When producing products such as ammonium polyphosphate, 85% phosphoric acid is usually required. The crystallization point (freezing point) of 85% phosphoric acid is 21°C. When the temperature is lower than this temperature, hemihydrate crystals will precipitate. In a static state, as long as such a low temperature is maintained for a period of time, phosphoric acid is very easy to crystallize.

[0003] Large phosphoric acid storage tanks in factories (the storage tank material is generally 316L stainless steel) are usually arranged outdoors. When the temperature is low in winter, crystallization is extremely likely to occur, resulting in the inability of 85% phosphoric acid to be pumped to the acid-using position.

[0004] Existing treatment methods:

[0005] ⑴ Use 75% phosphoric acid instead of 85% phosphoric acid. Because the crystallization point of 75% phosphoric acid is lower, it is not as easy to crystallize as 85% phosphoric acid. However, if the outdoor temperature is extremely low, lower than 4°C, 75% phosphoric acid will also crystallize, and the use effect of 75% phosphoric acid in production is not as good as that of 85% phosphoric acid.

[0006] ⑵ Add heat tracing facilities outside the phosphoric acid storage tank, such as a steam heating jacket (because the steam temperature is high, it will cause corrosion of the 316L storage tank), and an electric heating tape wound outside the tank (the failure rate is high outdoors and the energy consumption is high). Summary of the Utility Model

[0007] In view of the above defects, the utility model provides a device for stably transporting phosphoric acid to a production line by using the waste heat of the production line, which can stably transport 85% phosphoric acid to the production line.

[0008] A device for stably transporting phosphoric acid to a production line by utilizing the waste heat of the production line, which is used to transport 85% phosphoric acid in the production of ammonium polyphosphate, includes a first phosphoric acid storage tank and a second phosphoric acid storage tank. A first acid discharge pipe is connected to the bottom of the first phosphoric acid storage tank, and a second acid discharge pipe is connected to the bottom of the second phosphoric acid storage tank. The device for stably transporting phosphoric acid to the production line by utilizing the waste heat of the production line further includes a constant temperature hot water tank, a waste heat fluid pipeline of the production line, and a main phosphoric acid pipe. The first acid discharge pipe and the second acid discharge pipe are respectively communicated with the main phosphoric acid pipe. The waste heat fluid pipeline of the production line is connected to the constant temperature hot water tank. A first hot water heating jacket is arranged outside the bottom of the first phosphoric acid storage tank, and a second hot water heating jacket is arranged outside the bottom of the second phosphoric acid storage tank. The device for transporting phosphoric acid further includes a heat preservation water pipe and a heat preservation water return pipe. A first pump is installed on the heat preservation water pipe. The heat preservation water pipe is respectively communicated with the first hot water heating jacket, the second hot water heating jacket, and the constant temperature hot water tank. The heat preservation water return pipe is respectively communicated with the first hot water heating jacket, the second hot water heating jacket, and the constant temperature hot water tank. A second pump is installed on the output section of the main phosphoric acid pipe. The outlet of the second pump is connected with a conveying pipe for production line use.

[0009] In one or more optional embodiments of the present utility model, the device for stably transporting phosphoric acid to the production line by utilizing the waste heat of the production line further includes a circulating acid pipe, the circulating acid pipe is connected to the conveying pipe for production line use, the second pump is a phosphoric acid preparation pump, and the circulating acid pipe is also respectively communicated with the first phosphoric acid storage tank and the second phosphoric acid storage tank.

[0010] In one or more optional embodiments of the present utility model, the device for stably transporting phosphoric acid to the production line by utilizing the waste heat of the production line further includes a phosphoric acid connecting pipe, one end of the phosphoric acid connecting pipe is communicated with the first phosphoric acid storage tank, and the other end is communicated with the second phosphoric acid storage tank. The phosphoric acid connecting pipe is located at the highest liquid level control line of the first phosphoric acid storage tank and the second phosphoric acid storage tank.

[0011] In one or more optional embodiments of the present utility model, a steam distributor is arranged at the bottom of the constant temperature hot water tank, and the steam distributor is communicated with the waste heat steam in the waste heat fluid pipeline of the production line.

[0012] In one or more optional embodiments of the present utility model, a safety valve is installed on the constant temperature hot water tank.

[0013] In one or more alternative embodiments of the present utility model, the device for stably conveying phosphoric acid to the production line by utilizing the waste heat of the production line further includes a PLC controller. A first electromagnetic valve is installed on the heat-insulated water pipe at the outlet of the first pump. A second electromagnetic valve is installed on the pipeline connecting the heat-insulated water pipe and the first hot water heating jacket. A third electromagnetic valve is installed on the pipeline connecting the heat-insulated water pipe and the second hot water heating jacket. A fourth electromagnetic valve is installed on the first acid discharge pipe. A fifth electromagnetic valve is installed on the second acid discharge pipe. A sixth electromagnetic valve is installed on the conveying pipe used by the production line. The circulating acid pipe is located between the sixth electromagnetic valve and the second pump. A seventh electromagnetic valve is installed near the conveying pipe used by the production line on the circulating acid pipe. An eighth electromagnetic valve is installed on the pipeline connecting the circulating acid pipe and the first phosphoric acid storage tank. A ninth electromagnetic valve is installed on the pipeline connecting the circulating acid pipe and the second phosphoric acid storage tank. A first acid temperature sensor is installed on the first phosphoric acid storage tank. A second acid temperature sensor is installed on the second phosphoric acid storage tank. A first ultrasonic level sensor is installed on the first phosphoric acid storage tank. A second ultrasonic level sensor is installed on the first phosphoric acid storage tank 2. A water temperature sensor and a magnetic flap level gauge are installed on the constant temperature hot water tank. The PLC controller is respectively connected to the first acid temperature sensor, the second acid temperature sensor, the first ultrasonic level sensor, the second ultrasonic level sensor, the water temperature sensor, the magnetic flap level gauge, the first electromagnetic valve, the second electromagnetic valve, the third electromagnetic valve, the fourth electromagnetic valve, the fifth electromagnetic valve, the sixth electromagnetic valve, the seventh electromagnetic valve, the eighth electromagnetic valve, the ninth electromagnetic valve, the first pump, and the second pump.

[0014] In one or more alternative embodiments of the present utility model, the first electromagnetic valve is a three-way electromagnetic valve, and the three-way electromagnetic valve is further connected to a drain pipe, and the drain pipe is connected to the in-plant circulating water collection pool.

[0015] Advantages of the invention:

[0016] The present utility model adopts a hot water heating jacket arranged outside the tank bottom, utilizes the waste heat of the factory, cooperates with a constant temperature hot water tank, and controls the hot water temperature at 30 - 40 °C through PLC. When the acid temperature is lower than the set temperature, the temperature of the constant temperature hot water tank is automatically adjusted, and the second electromagnetic valve and the third electromagnetic valve are opened to let water in. When the acid temperature reaches a certain level, the fourth electromagnetic valve and the fifth electromagnetic valve are opened, the second pump is started, and the seventh electromagnetic valve, the eighth electromagnetic valve, and the ninth electromagnetic valve on the circulating acid pipe are opened for closed-loop circulation operation to increase the overall tank temperature and prevent the crystallization from accelerating under the static state. Description of the drawings

[0017] Figure 1 It is a schematic diagram of the overall structure of the present utility model;

[0018] In the figure: 1. First phosphoric acid storage tank; 2. Second phosphoric acid storage tank; 3. Constant temperature hot water tank; 4. Waste heat fluid pipeline of the production line; 5. First hot water heating jacket; 6. Second hot water heating jacket; 7. Heat preservation water pipe; 8. Main phosphoric acid pipe; 9. Second pump; 10. Circulating acid pipe; 11. Delivery pipe for production line use; 12. First pump; 13. Drain pipe; 14. Phosphoric acid connecting pipe; 15. Heat preservation water return pipe; 16. Steam distributor; 17. Safety valve. Detailed implementation mode

[0019] The present utility model will be further described below.

[0020] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "longitudinal", "lateral", "horizontal", "inner", "outer", "front", "rear", "top", "bottom", etc. is the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present utility model is usually placed during use. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model. In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0021] In the description of the present utility model, it should also be noted that unless otherwise clearly specified and defined, the terms "set", "provided with", "installed", "connected", "connected to" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0022] Please refer to Figure 1 , Figure 1 , which is the overall structural schematic diagram of the present utility model.

[0023] A device for stably transporting phosphoric acid to a production line, comprising a first phosphoric acid storage tank 1, a second phosphoric acid storage tank 2, a constant-temperature hot water tank 3, a production line waste heat fluid pipeline 4 and a main phosphoric acid pipeline 8. A first acid discharge pipe is connected to the bottom of the first phosphoric acid storage tank 1, and a second acid discharge pipe is connected to the bottom of the second phosphoric acid storage tank 2. The first acid discharge pipe and the second acid discharge pipe are respectively communicated with the main phosphoric acid pipeline 8. The production line waste heat fluid pipeline 4 is connected to the constant-temperature hot water tank 3. A first hot water heating jacket 5 is arranged outside the bottom of the first phosphoric acid storage tank 1, and a second hot water heating jacket 6 is arranged outside the bottom of the second phosphoric acid storage tank 2. The device for transporting phosphoric acid further comprises a heat preservation water pipe 7 and a heat preservation water return pipe 15. A first pump 12 is installed on the heat preservation water pipe 7. The heat preservation water pipe 7 is respectively communicated with the first hot water heating jacket 5, the second hot water heating jacket 6 and the constant-temperature hot water tank 3. The heat preservation water return pipe 15 is respectively communicated with the first hot water heating jacket 5, the second hot water heating jacket 6 and the constant-temperature hot water tank 3. A second pump 9 is installed on the output section of the main phosphoric acid pipeline 8. The outlet of the second pump 9 is connected to a production line use conveying pipe 11.

[0024] Through the settings of the constant-temperature hot water tank 3, the production line waste heat fluid pipeline 4, the first hot water heating jacket 5 and the second hot water heating jacket 6, when the acid temperature is lower than the set temperature, the production line waste heat of the constant-temperature hot water tank 3 is input into the second hot water heating jacket 6 or the first hot water heating jacket 5 to heat the first phosphoric acid storage tank 1 and the second phosphoric acid storage tank 2 to prevent 85% phosphoric acid from crystallizing. When the production line needs acid, 85% phosphoric acid can be transported to the production line at any time.

[0025] In one or more specific embodiments of the present utility model, for the convenience of control, a first solenoid valve is installed on the heat preservation water pipe 7 at the outlet of the first pump 12, a second solenoid valve is installed on the pipeline where the heat preservation water pipe 7 is communicated with the first hot water heating jacket 5, and a third solenoid valve is installed on the pipeline where the heat preservation water pipe 7 is communicated with the second hot water heating jacket 6. The second solenoid valve and the third solenoid valve are used to control whether the heat preservation water enters the first hot water heating jacket 5 and the second hot water heating jacket 6.

[0026] In one or more specific embodiments of the present utility model, for the convenience of control, a fourth solenoid valve is installed on the first acid discharge pipe, a fifth solenoid valve is installed on the second acid discharge pipe, and a sixth solenoid valve is installed on the production line use conveying pipe 11. The fourth solenoid valve and the fifth solenoid valve are used to control whether the phosphoric acid is discharged from the tank, and the sixth solenoid valve is used to control whether the phosphoric acid is transported to the production line.

[0027] In one or more specific embodiments of the present utility model, the first solenoid valve is a three-way solenoid valve, and the three-way solenoid valve is further connected to a drain pipe 13, and the drain pipe 13 is connected to the in-plant circulating water collection pool.

[0028] Those skilled in the art need to know that in the present utility model, the waste heat fluid of the production line can be waste hot water, can also be waste heat steam, or can have both waste hot water and waste heat steam, which is determined according to the actual waste heat supply of the production line and is not specifically limited herein.

[0029] In one or more specific embodiments of the present utility model, the device for stably conveying phosphoric acid to the production line further includes a circulating acid pipe 10. The circulating acid pipe 10 is connected to the production line use conveying pipe 11, and is located between the sixth solenoid valve and the second pump 9. A seventh solenoid valve is installed at the position where the circulating acid pipe 10 is close to the production line use conveying pipe 11. The second pump 9 is a phosphoric acid preparation pump. The circulating acid pipe 10 is also respectively communicated with the first phosphoric acid storage tank 1 and the second phosphoric acid storage tank 2. Further, an eighth solenoid valve is installed on the pipeline where the circulating acid pipe 10 is communicated with the first phosphoric acid storage tank 1, and a ninth solenoid valve is installed on the pipeline where the circulating acid pipe 10 is communicated with the second phosphoric acid storage tank 2. When the temperature of the phosphoric acid reaches a certain temperature, the fourth solenoid valve and the fifth solenoid valve are opened, the second pump 9 is started, and the seventh solenoid valve, the eighth solenoid valve and the ninth solenoid valve are opened for closed-loop circulation operation to increase the overall tank temperature and prevent the crystallization from accelerating under the static state.

[0030] In one or more specific embodiments of the present utility model, the device for stably conveying phosphoric acid to the production line further includes a phosphoric acid connecting pipe 14. One end of the phosphoric acid connecting pipe 14 is communicated with the first phosphoric acid storage tank 1, and the other end is communicated with the second phosphoric acid storage tank 2. The phosphoric acid connecting pipe 14 is located at the highest liquid level control line of the first phosphoric acid storage tank 1 and the second phosphoric acid storage tank 2. When the liquid level of one phosphoric acid storage tank is too high, it is transferred to the other phosphoric acid storage tank to control the liquid level of the phosphoric acid storage tank not to exceed the control line.

[0031] In one or more specific embodiments of the present utility model, a steam distributor 16 is arranged at the bottom of the constant temperature hot water tank 3. The steam distributor 16 is communicated with the waste heat steam in the production line waste heat fluid pipeline 4.

[0032] In one or more specific embodiments of the present utility model, a safety valve 17 is installed on the constant temperature hot water tank 3 for constant temperature safety.

[0033] In one or more specific embodiments of the present utility model, in order to reduce labor costs and improve the degree of automation, the device for stably conveying phosphoric acid to the production line further includes a PLC controller. The first phosphoric acid storage tank 1 is equipped with a first acid temperature sensor, the second phosphoric acid storage tank 2 is equipped with a second acid temperature sensor, the first phosphoric acid storage tank 1 is equipped with a first ultrasonic level sensor, the second phosphoric acid storage tank 2 is equipped with a second ultrasonic level sensor, the constant temperature hot water tank 3 is equipped with a water temperature sensor and a magnetic flap level gauge. The PLC controller is respectively connected to the first acid temperature sensor, the second acid temperature sensor, the first ultrasonic level sensor, the second ultrasonic level sensor, the water temperature sensor, the magnetic flap level gauge, the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve, the fifth solenoid valve, the sixth solenoid valve, the seventh solenoid valve, the eighth solenoid valve, the ninth solenoid valve, the first pump 12, and the second pump 9. When in use, the PLC controller controls the hot water temperature to be 30 - 40 °C. When the acid temperature is lower than the set temperature, the temperature of the constant temperature hot water tank 3 is automatically adjusted, and the second solenoid valve and the third solenoid valve are opened to let water in. When the acid temperature reaches a certain level, the fourth solenoid valve and the fifth solenoid valve are opened, the second pump 9 is started, and the seventh solenoid valve, the eighth solenoid valve, and the ninth solenoid valve on the circulating acid pipe 10 are opened for closed-loop circulation operation to increase the overall tank temperature and prevent the crystallization from accelerating under the static state. During operation, only when the temperature of the corresponding acid temperature sensor is higher than the set value can the sixth solenoid valve be opened to adjust the acid to each acid point for production use, preventing the phosphoric acid in the pipeline from solidifying due to low temperature.

[0034] Those skilled in the art need to know that in the present utility model, the PLC automatic control system is purchased from the market.

[0035] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A device for stably conveying phosphoric acid to a production line by utilizing waste heat of a production line, which is used for conveying 85% phosphoric acid in ammonium polyphosphate production, comprising a first phosphoric acid storage tank (1) and a second phosphoric acid storage tank (2), wherein the bottom of the first phosphoric acid storage tank (1) is connected to a first acid discharge pipe, and the bottom of the second phosphoric acid storage tank (2) is connected to a second acid discharge pipe, characterized in that: The device for stably conveying phosphoric acid to the production line by utilizing the waste heat of the production line further comprises a constant temperature hot water tank (3), a waste heat fluid pipeline (4) of the production line and a phosphoric acid main pipeline (8), the first acid discharge pipeline and the second acid discharge pipeline are respectively connected to the phosphoric acid main pipeline (8), the waste heat fluid pipeline (4) of the production line is connected to the constant temperature hot water tank (3), a first hot water heating jacket (5) is arranged outside the bottom of the first phosphoric acid storage tank (1), a second hot water heating jacket (6) is arranged outside the bottom of the second phosphoric acid storage tank (2), and the device for conveying phosphoric acid further comprises a heat preservation water The heat preservation water pipe (7) and the heat preservation water return pipe (15) are connected to each other. The heat preservation water pipe (7) is provided with a first pump (12). The heat preservation water pipe (7) is respectively connected to the first hot water heating jacket (5), the second hot water heating jacket (6) and the constant temperature hot water tank (3). The heat preservation water return pipe (15) is respectively connected to the first hot water heating jacket (5), the second hot water heating jacket (6) and the constant temperature hot water tank (3). The output section of the phosphoric acid main pipe (8) is provided with a second pump (9). The outlet of the second pump (9) is connected to a delivery pipe (11) used by the production line.

2. The device for stably conveying phosphoric acid to a production line by utilizing the waste heat of a production line according to claim 1, characterized in that: The device for stably conveying phosphoric acid to the production line by utilizing the residual heat of the production line further comprises a circulating acid pipe (10), the circulating acid pipe (10) being connected to the production line use conveying pipe (11), the second pump (9) being a phosphoric acid preparation pump, and the circulating acid pipe (10) being also respectively connected to the first phosphoric acid storage tank (1) and the second phosphoric acid storage tank (2).

3. The device for stably conveying phosphoric acid to a production line by utilizing the residual heat of a production line according to claim 1, characterized in that: The device for stably conveying phosphoric acid to the production line by utilizing the residual heat of the production line further comprises a phosphoric acid connecting pipe (14), one end of the phosphoric acid connecting pipe (14) being connected to the first phosphoric acid storage tank (1), and the other end of the phosphoric acid connecting pipe (14) being connected to the second phosphoric acid storage tank (2), and the phosphoric acid connecting pipe (14) being located at the highest liquid level control line of the first phosphoric acid storage tank (1) and the second phosphoric acid storage tank (2).

4. The device for stably conveying phosphoric acid to a production line by utilizing the residual heat of a production line according to claim 1, characterized in that: A steam distributor (16) is provided at the bottom of the constant temperature hot water tank (3), and the steam distributor (16) is connected to the production line waste heat steam in the production line waste heat fluid pipeline (4).

5. The device for stably conveying phosphoric acid to a production line by utilizing the residual heat of a production line according to claim 1, characterized in that: The constant temperature hot water tank (3) is provided with a safety valve (17).

6. The device for stably conveying phosphoric acid to a production line by utilizing the residual heat of a production line according to any one of claims 2 to 5, characterized in that: The device for stably conveying phosphoric acid to the production line by utilizing the residual heat of the production line further comprises a PLC controller, a first solenoid valve is installed on the insulation water pipe (7) at the outlet of the first pump (12), a second solenoid valve is installed on the pipeline connecting the insulation water pipe (7) and the first hot water heating jacket (5), and a third solenoid valve is installed on the pipeline connecting the insulation water pipe (7) and the second hot water heating jacket (6); a fourth solenoid valve is installed on the first acid discharge pipe, a fifth solenoid valve is installed on the second acid discharge pipe, and a sixth solenoid valve is installed on the production line delivery pipe (11); the circulating acid pipe (10) is located between the sixth solenoid valve and the second pump (9), a seventh solenoid valve is installed on the circulating acid pipe (10) adjacent to the production line delivery pipe (11), an eighth solenoid valve is installed on the pipeline connecting the circulating acid pipe (10) and the first phosphoric acid storage tank (1), and the circulating acid pipe (10) is provided with a plurality of solenoid valves. A ninth solenoid valve is installed on the pipeline connecting the cyclic acid pipe (10) and the second phosphoric acid storage tank (2); the first phosphoric acid storage tank (1) is installed with a first acid temperature sensor, the second phosphoric acid storage tank (2) is installed with a second acid temperature sensor, the first phosphoric acid storage tank (1) is installed with a first ultrasonic liquid level sensor, the first phosphoric acid storage tank 2 is installed with a second ultrasonic liquid level sensor, and the constant temperature hot water tank (3) is installed with a water temperature sensor and a magnetic flap liquid level gauge; and a PLC controller is respectively connected to the first acid temperature sensor, the second acid temperature sensor, the first ultrasonic liquid level sensor, the second ultrasonic liquid level sensor, the water temperature sensor, the magnetic flap liquid level gauge, the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve, the fifth solenoid valve, the sixth solenoid valve, the seventh solenoid valve, the eighth solenoid valve, the ninth solenoid valve, the first pump (12), and the second pump (9).

7. The device for stably conveying phosphoric acid to a production line by utilizing the residual heat of a production line according to claim 6, characterized in that: The first solenoid valve is a three-way solenoid valve, which is also connected to a drainage pipe (13), and the drainage pipe (13) is connected to a circulating water collection pool in the factory.

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