Production system of nitro-compound fertilizer

Abstract

The utility model discloses a production system of a nitro-compound fertilizer, and belongs to the technical field of compound fertilizers. Comprising a melting tank, a first-stage mixing tank, a second-stage mixing tank, a uniform mixer, a granulation tower and a discharging heat-preservation conveying pipe, the heights of the melting tank, the first-stage mixing tank and the second-stage mixing tank are sequentially reduced, an overflow port of the melting tank is connected with a feeding port of the first-stage mixing tank, and an overflow port of the first-stage mixing tank is connected with a feeding port of the second-stage mixing tank; a feed port of the uniform mixer is directly connected with an overflow port of the secondary mixing tank, and a first powder spraying discharge port is formed in the upper part of the uniform mixer; a discharge port of the melting tank is connected with a feed port of the secondary mixing tank; the first-stage mixing tank, the second-stage mixing tank and a discharge port of the uniform mixer are connected with a discharge heat-preservation conveying pipe; a second powder spraying and discharging opening is formed in the discharging end of the discharging heat preservation conveying pipe; the granulation tower is connected with one of the first powder spraying discharge port and the second powder spraying discharge port; during production, the granulation tower is connected with the first powder spraying discharge hole; and during shutdown, the granulation tower is connected with the second powder spraying discharge port.

Description

Technical Field

[0001] This utility model belongs to the field of compound fertilizer technology, and specifically relates to a production system for nitro compound fertilizer. Background Technology

[0002] High-tower compound fertilizer adopts melt urea carrier tower granulation technology, which uses molten urea and raw materials such as phosphorus and potassium, which are fully mixed and sprayed down from the top of the tower, and then naturally cooled and granulated.

[0003] For example, patent application number CN201510500998.6 discloses a method for preventing the combustion and explosion of ammonium nitrate in the process of producing nitrate-sulfur-based compound fertilizer by high-tower granulation. The method includes the following steps:

[0004] Step 1: Design a device to prevent ammonium nitrate from igniting or exploding. This device should include an over-temperature alarm interlock protection system, a belt feeder, a heating steam supply unit, a water supply unit, and sequentially connected intermediate tanks, a melter, a first mixing tank, a second mixing tank, a homogenizer, and a granulator. Ammonium nitrate is sequentially fed into the intermediate tank, melter, first mixing tank, second mixing tank, homogenizer, and granulator. The intermediate tank, melter, first mixing tank, and second mixing tank are each connected to the heating steam supply unit via heating steam pipelines, and each heating steam pipeline is equipped with a heating steam valve. The intermediate tank, melter, first mixing tank, second mixing tank, and granulator are each connected to the water supply unit via water supply pipelines, and each water supply pipeline is equipped with a water supply valve. The intermediate tank and the melter, as well as the melter and the first mixing tank, are all connected via ammonium nitrate delivery pipelines. A first ammonium nitrate feed pump is installed at the feed end of the intermediate tank, and a second ammonium nitrate feed pump is installed on the ammonium nitrate delivery pipeline between the intermediate tank and the melter. An ammonium nitrate solution feed valve is installed on the ammonium nitrate delivery pipeline between the melter and the first mixing tank. The first mixing tank and the second mixing tank, the second mixing tank and the homogenizer, and the homogenizer and the granulator are all connected via mixed material delivery pipelines. A first mixed material feed valve is installed on the mixed material delivery pipeline between the first and second mixing tanks, and a second mixed material feed valve is installed on the mixed material delivery pipeline between the second mixing tank and the homogenizer. A third mixed material is installed on the mixed material delivery pipeline between the homogenizer and the granulator. Feed valves; discharge valves are installed on the intermediate tank, melter, No. 1 mixing tank, No. 2 mixing tank, and homogenizer; a first raw material feed valve is installed at the feed end of the melter, a second raw material feed valve is installed at the feed end of the No. 1 mixing tank, and a third raw material feed valve is installed at the feed end of the No. 2 mixing tank; the over-temperature alarm interlock protection system needs to include a controller, a first temperature sensor installed on the intermediate tank, a second temperature sensor installed on the melter, a third temperature sensor installed on the No. 1 mixing tank, and a fourth temperature sensor installed on the No. 2 mixing tank. The first, second, third, and fourth temperature sensors and the belt feeder are respectively connected to the controller for communication. At the same time, alarm temperature values ​​for the intermediate tank, melter, No. 1 mixing tank, and No. 2 mixing tank are set in the controller.

[0005] Step 2: Add monoammonium phosphate and potassium dihydrogen phosphate to mixing tank No. 1 via belt feeder, and add potassium sulfate and potassium chloride to mixing tank No. 2.

[0006] Step 3: Use the first temperature sensor to monitor the temperature in the intermediate tank in real time and transmit the collected temperature value to the controller in real time; use the second temperature sensor to monitor the temperature in the melt in real time and transmit the collected temperature value to the controller in real time; use the third temperature sensor to monitor the temperature in the first mixing tank in real time and transmit the collected temperature value to the controller in real time; use the fourth temperature sensor to monitor the temperature in the second mixing tank in real time and transmit the collected temperature value to the controller in real time; when the temperature in the intermediate tank, melt, first mixing tank, and second mixing tank exceeds the set value, the controller issues a control command.

[0007] For example, patent application number CN201721015125.7 discloses a nitro compound fertilizer production system, including: a first conveying line and a second conveying line, each including a batching device, a screening machine, a screw conveyor, a high-tower elevator, and a mixing silo connected in sequence; a primary mixing tank connected to the mixing silo of the first conveying line; and a secondary mixing tank connected to the mixing silo of the second conveying line. The secondary mixing tank is connected to the finished product silo in sequence through a homogenizer I, a granulator, a granulation tower, a disc scraper, a cooling screening device, and an oil film coating device. The primary mixing tank is connected to the secondary mixing tank in sequence through a homogenizer II and a flash evaporator. In the second conveying line, the batching device includes a feeding silo I for adding base fertilizer and a feeding silo II for adding additives. The feeding silo I and the feeding silo II are connected in sequence. Each of the two silos (II and III) is fed to a consolidation belt via a batching belt, which then feeds the material to a screening machine. The screening machine also returns material to the consolidation belt via a crusher. The returned material from the cooling screening device is returned to a melting tank via a high-tower elevator (III). An ammonium nitrate neutralization device is connected to the melting tank via a first ammonium nitrate flash evaporation device. A dehumidification device is connected to a second cooling drum. A controller and an operating station connected to the controller are also included. The melting tank, the primary mixing tank, and the secondary mixing tank are all equipped with stirring motors and heating devices. The high-tower elevator, the disc scraper, the dehumidification device, the stirring motor, the heating device, the crusher, and the batching belt are all equipped with electrical instruments, which are all connected to the controller.

[0008] Existing compound fertilizer preparation systems typically include a melting tank, a primary mixing tank, a secondary mixing tank, a homogenizer, and a granulation tower connected in sequence. The applicant discovered the following issues while using the existing compound fertilizer system: 1. The quality of the raw materials used in compound fertilizer is not good (e.g., agricultural grade ammonium phosphate is used), leading to unstable product quality and potentially substandard active ingredients (key indicators for compound fertilizer, typically nitrogen, phosphorus, and potassium content); 2. After shutdown, the raw materials in each structure rapidly solidify, causing equipment blockage. Summary of the Invention

[0009] To address the aforementioned problems, this utility model provides a production system for nitro compound fertilizer. Material conveying does not require pumps, and the output is entirely overflow, resulting in high-quality compound fertilizer. After shutdown, residual material from each component is sent to a granulation tower for granulation, ensuring product quality and preventing material agglomeration and equipment blockage. The technical solution is as follows:

[0010] This utility model embodiment provides a production system for nitro compound fertilizer. The system includes a melting tank 1, a primary mixing tank 2, a secondary mixing tank 3, a homogenizer 4, a granulation tower 5, and a discharge insulated conveying pipe 14. The melting tank 1 is connected to a nitro-ammonium phosphate supply system 6 and a return system. The primary mixing tank 2 is connected to a potassium salt supply system 7, and the secondary mixing tank 3 is connected to a phosphate-ammonium supply system 8. The heights of the melting tank 1, primary mixing tank 2, and secondary mixing tank 3 decrease sequentially. The overflow port at the top of the melting tank 1 is connected to the feed inlet at the top of the primary mixing tank 2 via a downward-sloping first insulated conveying pipe 11. The overflow port at the top of the primary mixing tank 2 is connected to the feed inlet at the top of the secondary mixing tank 3 via a downward-sloping second insulated conveying pipe 12. The homogenizer 4 is arranged side-by-side with the secondary mixing tank 3, and its upper feed inlet is directly connected to the upper overflow port of the secondary mixing tank 3. A first powder spraying outlet is provided at the top of the homogenizer 4. 15; The discharge port at the bottom of the melting tank 1 is equipped with a first valve, which is connected to the feed port at the top of the secondary mixing tank 3 via a downwardly inclined third insulated conveying pipe 13; The discharge port at the bottom of the primary mixing tank 2 is equipped with a second valve, which is connected to the discharge insulated conveying pipe 14; The discharge port at the bottom of the secondary mixing tank 3 is equipped with a third valve, which is connected to the discharge insulated conveying pipe 14; The discharge port at the bottom of the homogenizer 4 is equipped with a fourth valve, which is connected to the discharge insulated conveying pipe 14; The discharge insulated conveying pipe 14 is located below the secondary mixing tank 3 and its discharge end is equipped with a second powder spraying outlet 16; The granulation tower 5 is equipped with a powder spraying pump 18, and its inlet is selectively connected to either the first powder spraying outlet 15 or the second powder spraying outlet 16; During production, the inlet of the granulation tower 5 is connected to the first powder spraying outlet 15; When shutting down, the inlet of the granulation tower 5 is connected to the second powder spraying outlet 16.

[0011] Specifically, in this embodiment of the present invention, there are two melting tanks 1, which are arranged side by side.

[0012] In one embodiment of this patent, a flexible hose 17 is provided on both the first powder spraying outlet 15 and the second powder spraying outlet 16. The end of the flexible hose 17 is provided with a quick-connect buckle on the feed inlet of the granulation tower 5. The flexible hose 17 is detachably connected to the feed inlet of the granulation tower 5.

[0013] In another embodiment of this patent, the first powder spraying outlet 15 and the second powder spraying outlet 16 are connected to the two inlets of a three-way valve, and the outlet of the three-way valve is connected to the inlet of the granulation tower 5.

[0014] The production system for nitro compound fertilizer provided in this embodiment of the present invention also includes an elevated tank 9 and a tail gas treatment device 10. The tail gas outlets of the melting tank 1, the primary mixing tank 2, and the secondary mixing tank 3 are connected to the tail gas treatment device 10 through pipelines, and their water inlets are connected to the elevated tank 9 through equalization pipelines. The elevated tank 9 is higher than the circulation tank of the melting tank 1, the primary mixing tank 2, the secondary mixing tank 3, and the tail gas treatment device 10, and the water inlet of the circulation tank is connected to the elevated tank 9 through a pipeline.

[0015] Specifically, in this embodiment of the present invention, a loss-in-weight scale 19 is provided directly above the secondary mixing tank 3. The loss-in-weight scale 19 is used to add other raw materials besides ammonium nitrate phosphate, potassium salt and ammonium phosphate.

[0016] The beneficial effects of the technical solution provided by this utility model embodiment are as follows: This utility model embodiment provides a production system for nitro compound fertilizer. The material conveying does not require a pump (the powder spraying pump mainly plays the role of powder spraying, and at the same time, it sends the slurry from the homogenizer to the granulation tower) and the output is all overflow (impurities settle at the bottom of each tank). The quality of the prepared compound fertilizer is good (impurities have settled and are included in the powder spraying product after shutdown). After shutdown, the remaining material of each structure is sent to the granulation tower for granulation (to be discarded or sold as a low-quality product, etc.), which not only ensures the quality of the product (the slurry at the bottom of each tank contains a lot of impurities), but also avoids material agglomeration and clogging of the equipment. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the production system for nitro compound fertilizer provided in Example 1;

[0018] Figure 2 This is a schematic diagram of the production system for nitro compound fertilizer provided in Example 2;

[0019] Figure 3 This is a schematic diagram illustrating the principle of exhaust gas treatment and cleaning process;

[0020] Figure 4 This is a schematic diagram of the production system for nitro compound fertilizer provided in Example 1.

[0021] In the diagram: 1 Melting tank, 2 Primary mixing tank, 3 Secondary mixing tank, 4 Homogenizer, 5 Granulation tower, 6 Ammonium nitrate phosphate supply system, 7 Potassium salt supply system, 8 Ammonium phosphate supply system, 9 High-level tank, 10 Tail gas treatment device, 11 First insulated conveying pipe, 12 Second insulated conveying pipe, 13 Third insulated conveying pipe, 14 Discharge insulated conveying pipe, 15 First powder spraying outlet, 16 Second powder spraying outlet, 17 Hoses, 18 Powder spraying pump, 19 Loss-in-weight scale. Detailed Implementation

[0022] To make the objectives, technical solutions and advantages of this utility model clearer, the utility model will be described in further detail below with reference to the accompanying drawings.

[0023] Example 1

[0024] See Figure 1 and 3-4. Example 1 provides a production system for nitro compound fertilizer. This system includes a melting tank 1, a primary mixing tank 2, a secondary mixing tank 3, a homogenizer 4, a granulation tower 5, a discharge and heat-insulated conveying pipe 14, a loss-in-weight scale 19, an elevated tank 9, and a tail gas treatment device 10. The melting tank 1 is connected to the ammonium nitrate phosphate supply system 6 and the return material system for adding ammonium nitrate phosphate and returning material. The primary mixing tank 2 is connected to the potassium salt supply system 7 for adding potassium salt. The secondary mixing tank 3 is connected to the ammonium phosphate supply system 8 for adding ammonium phosphate. The loss-in-weight scale 19 is located directly above the secondary mixing tank 3 and is used to add other raw materials (such as additives, humic acid, trace elements, etc.) besides ammonium nitrate phosphate, potassium salt, and ammonium phosphate to the secondary mixing tank 3. The heights of the melting tank 1, the primary mixing tank 2, and the secondary mixing tank 3 decrease sequentially, with the bottom of the melting tank 1 being higher than the top of the secondary mixing tank 3. The overflow port at the top of the melting tank 1 is connected to the feed port at the top of the primary mixing tank 2 via a downward-sloping first insulated conveying pipe 11. The overflow port at the top of the primary mixing tank 2 is connected to the feed port at the top of the secondary mixing tank 3 via a downward-sloping second insulated conveying pipe 12. The homogenizer 4 is arranged side by side with the secondary mixing tank 3, and its upper feed port is directly connected to the upper overflow port of the secondary mixing tank 3. A first powder spraying outlet 15 is provided at its top. A first valve is provided on the discharge port at the bottom of the melting tank 1, and it is connected to the upper feed port of the secondary mixing tank 3 via a downward-sloping third insulated conveying pipe 13 to form a height difference. A second valve is installed at the discharge port at the bottom of the primary mixing tank 2, and it is connected to the discharge insulated conveying pipe 14. A third valve is installed at the discharge port at the bottom of the secondary mixing tank 3, and it is connected to the discharge insulated conveying pipe 14. A fourth valve is installed at the discharge port at the bottom of the homogenizer 4, and it is connected to the discharge insulated conveying pipe 14. The discharge insulated conveying pipe 14 is located below the secondary mixing tank 3, and its discharge end is equipped with a second powder spraying outlet 16. The granulation tower 5 is equipped with a powder spraying pump 18 (for powder spraying), and its inlet is connected to either the first powder spraying outlet 15 or the second powder spraying outlet 16. The tail gas outlets of the melting tank 1, the primary mixing tank 2, and the secondary mixing tank 3 are connected to the tail gas treatment device 10 through pipelines, and their water inlets are connected to the high-level tank 9 (for storing clean water or process water) through a homogenizing pipeline (equipped with a valve) for cleaning. The high-level tank 9 is higher than the melting tank 1, the primary mixing tank 2, the secondary mixing tank 3 and the circulation tank of the exhaust gas treatment device 10. The water inlet of the circulation tank is connected to the high-level tank 9 through a pipeline.

[0025] During production, the feed inlet of granulation tower 5 is connected to the first powder spraying outlet 15, and compound fertilizer is produced through overflow. At this time, the first, second, third, and fourth valves are closed. During shutdown, the feed inlet of granulation tower 5 is connected to the second powder spraying outlet 16 to drain residue and perform powder spraying to prevent equipment blockage. At this time, the first, second, third, and fourth valves are opened. Specifically, the first valve can be opened first, followed by the second, third, and fourth valves. During cleaning, the high-level tank 9 outputs cleaning water to the melting tank 1, the primary mixing tank 2, and the secondary mixing tank 3. The feed inlet of granulation tower 5 is connected to the second powder spraying outlet 16 to drain the cleaning liquid and perform powder spraying.

[0026] In this embodiment of the invention, the melting tank 1, the primary mixing tank 2, the secondary mixing tank 3, the homogenizer 4, the first insulated conveying pipe 11, the second insulated conveying pipe 12, the third insulated conveying pipe 13, and the discharge insulated conveying pipe 14 are all equipped with heating jackets (heated by steam); the melting tank 1, the primary mixing tank 2, the secondary mixing tank 3, and the homogenizer 4 are all equipped with a stirrer.

[0027] Both the first powder spraying outlet 15 and the second powder spraying outlet 16 are equipped with flexible hoses 17. The ends of the flexible hoses 17 are connected to the feed inlet of the granulation tower 5 via quick-connect couplings, allowing for detachable connection between the flexible hoses 17 and the feed inlet of the granulation tower 5. Specifically, the flexible hoses 17 are relatively short and do not require heating jackets. They are required to withstand high temperatures and can be made of corrugated metal.

[0028] In this embodiment, the exhaust gas treatment device 10 includes a spray tower, a circulation tank, and a circulation pump, which are consistent with the prior art. Detailed descriptions are omitted in this embodiment.

[0029] In this embodiment, the ammonium nitrate-phosphate supply system 6, the potassium salt supply system 7, and the ammonium phosphate supply system 8 include a feeder, a bucket elevator, a weighing scale, and a scraper conveyor, which are consistent with the prior art. Detailed descriptions are omitted in this embodiment.

[0030] Example 2

[0031] See Figure 2 Example 2 provides a nitro compound fertilizer production system, whose structure is basically the same as that of Example 1, except that: in this example, the first powder spraying outlet 15 and the second powder spraying outlet 16 are connected to the two inlets of a three-way valve, and the outlet of the three-way valve is connected to the inlet of the granulation tower 5. Switching is achieved by controlling the three-way valve.

[0032] Example 3

[0033] See Figure 4Example 3 provides a production system for nitro compound fertilizer, which has a structure that is basically the same as that of Example 1, except that: in this example, there are two melting tanks 1, which are arranged side by side.

[0034] Example 4

[0035] Example 4 provides a nitro compound fertilizer production system, the structure of which is basically the same as that of Example 1, except that the nitro compound fertilizer production system in this example is located in a 150,000-ton compound fertilizer production system.

[0036] In this embodiment, "first", "second", "third" and "fourth" serve only as distinctions and have no other special meanings.

[0037] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A production system for nitro compound fertilizer, comprising a melting tank (1), a primary mixing tank (2), a secondary mixing tank (3), a homogenizer (4), and a granulation tower (5), wherein the melting tank (1) is connected to a nitrophosphate supply system (6) and a return material system, the primary mixing tank (2) is connected to a potassium salt supply system (7), and the secondary mixing tank (3) is connected to a phosphate supply system (8); characterized in that, The production system also includes a discharge heat-insulating conveying pipe (14); the heights of the melting tank (1), the primary mixing tank (2), and the secondary mixing tank (3) decrease sequentially; the overflow port at the top of the melting tank (1) is connected to the feed port at the top of the primary mixing tank (2) via a downward-sloping first heat-insulating conveying pipe (11); the overflow port at the top of the primary mixing tank (2) is connected to the feed port at the top of the secondary mixing tank (3) via a downward-sloping second heat-insulating conveying pipe (12); the homogenizer (4) is arranged side by side with the secondary mixing tank (3), and its feed port is directly connected to the overflow port at the top of the secondary mixing tank (3); a first powder spraying outlet (15) is provided at the top of the melting tank (1); a first valve is provided at the discharge port at the bottom of the melting tank (1), and it is connected to the feed port at the top of the secondary mixing tank (3) via a downward-sloping third heat-insulating conveying pipe (13); The discharge port at the bottom of the primary mixing tank (2) is equipped with a second valve and is connected to the discharge heat-insulating conveying pipe (14). The discharge port at the bottom of the secondary mixing tank (3) is equipped with a third valve and is connected to the discharge heat-insulating conveying pipe (14). The discharge port at the bottom of the homogenizer (4) is equipped with a fourth valve and is connected to the discharge heat-insulating conveying pipe (14). The discharge heat-insulating conveying pipe (14) is located below the secondary mixing tank (3) and its discharge end is equipped with a second powder spraying outlet (16). The granulation tower (5) is equipped with a powder spraying pump (18) and its inlet is connected to either the first powder spraying outlet (15) or the second powder spraying outlet (16). During production, the inlet of the granulation tower (5) is connected to the first powder spraying outlet (15). When the granulation tower (5) is shut down, the inlet of the granulation tower (5) is connected to the second powder spraying outlet (16).

2. The production system for nitro compound fertilizer according to claim 1, characterized in that, The number of the melting tanks (1) is two, and the two melting tanks (1) are arranged side by side.

3. The production system for nitro compound fertilizer according to claim 1, characterized in that, Both the first powder spraying outlet (15) and the second powder spraying outlet (16) are equipped with hoses (17), and the ends of the hoses (17) and the feed inlet of the granulation tower (5) are equipped with quick-connect buckles. The hoses (17) are detachably connected to the feed inlet of the granulation tower (5).

4. The production system for nitro compound fertilizer according to claim 1, characterized in that, The first powder spraying outlet (15) and the second powder spraying outlet (16) are connected to the two inlets of the three-way valve, and the outlet of the three-way valve is connected to the inlet of the granulation tower (5).

5. The production system for nitro compound fertilizer according to claim 1, characterized in that, The production system also includes an elevated tank (9) and a tail gas treatment device (10). The tail gas outlets of the melting tank (1), the primary mixing tank (2), and the secondary mixing tank (3) are connected to the tail gas treatment device (10) through pipelines, and their water inlets are connected to the elevated tank (9) through equalization pipelines. The elevated tank (9) is higher than the circulation tank of the melting tank (1), the primary mixing tank (2), the secondary mixing tank (3), and the tail gas treatment device (10). The water inlet of the circulation tank is connected to the elevated tank (9) through pipelines.

6. The production system for nitro compound fertilizer according to claim 1, characterized in that, The secondary mixing tank (3) is provided with a loss-in-weight scale (19) directly above it. The loss-in-weight scale (19) is used to add raw materials other than ammonium nitrate, potassium salt and ammonium phosphate.

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