Low-temperature cold air circulation supply system in fertilizer production

Abstract

The utility model relates to fertilizer production equipment technical field, concretely is low temperature cold air circulation supply system in fertilizer preparation, including raw material warehouse, air pipe subassembly, first dust collector, second dust collector and high tower, the warehouse wall of raw material warehouse is opened to have the air intake, and the air intake place is installed with the air draught fan, and the air draught fan is used for containing the air of dust in raw material warehouse in turn via main air pipe, first dust collector and the air pipe of connection introduction high tower, the air pipe subassembly includes main air pipe and the air pipe of connection, the top of tower body is equipped with the feed inlet, and the bottom is equipped with the discharge gate, and the below of feed inlet is equipped with the granulating device, the upper part lateral wall of high tower is equipped with the waste gas discharge port, and the waste gas discharge port is connected to second dust collector through the pipeline, the bottom of second dust collector is equipped with the dust outlet, and the top is equipped with the exhaust port, and the exhaust port is connected filter box through the pipeline, and the gas outlet of filter box extends to the inside of high tower upper part. The utility model realizes the integration function of " once air draught - dust removal - cooling air supply simultaneously ".

Description

Technical Field

[0001] This utility model relates to the field of fertilizer production equipment technology, specifically a low-temperature cold air circulation supply system in fertilizer preparation. Background Technology

[0002] Existing compound fertilizer processing and production requires processes such as high-tower granulation, cooling, screening, coating, and packaging. After high-tower granulation, the high-temperature fertilizer granules need to undergo convective cooling to ensure the physical properties and storage stability of the fertilizer granules. At the same time, when storing fertilizer raw materials (such as nitrogen, phosphorus, and potassium raw material powders), the raw materials are prone to generating dust. If the dust escapes, it will cause environmental pollution and may also cause safety hazards. Therefore, the raw material silo needs to be equipped with dust removal devices.

[0003] In existing technology, the dust removal system of the raw material silo and the cooling air supply system of the tower are two independent sets of equipment. The dust removal system is only responsible for extracting dust-laden air from the raw material silo, purifying it, and then discharging it directly. The cooling air supply system, on the other hand, requires additional equipment such as fans and refrigeration units to extract air from the outside, cool it, and then introduce it into the tower. This independent setup has the following drawbacks: The equipment is numerous, occupies a large factory space, and has high equipment purchase and installation costs; the two systems operate separately, resulting in high energy consumption, which does not meet the production requirements for energy conservation and consumption reduction; when the cooling air supply system draws air from the outside, it requires a large amount of additional electricity to drive the fan, which increases the cost of cooling air preparation, and the outside air temperature is affected by ambient temperature and humidity, making it difficult to stably guarantee the low-temperature air supply required for high tower cooling.

[0004] Therefore, there is an urgent need for a technical solution that can integrate dust removal and cooling air supply functions, reduce energy consumption and costs, and ensure the stability of cooling air. Utility Model Content

[0005] The purpose of this invention is to address the problems of high equipment cost, high energy consumption, and poor cooling air stability caused by the independent operation of the raw material silo dust removal and high tower cooling air supply systems in the existing technology. This invention provides a low-temperature cold air circulation supply system for fertilizer preparation, which realizes the integrated function of "single-stage exhaust - synchronous dust removal - cooling air supply".

[0006] To solve the above problems, the technical solution adopted by this utility model is a low-temperature cold air circulation supply system for fertilizer preparation, including a raw material silo (1), a duct assembly (2), a first dust removal device (3), a second dust removal device (4), and a high tower (5).

[0007] The raw material silo (1) has an exhaust vent (11) on its wall. An exhaust fan (12) is installed at the exhaust vent (11). The exhaust fan (12) is used to introduce the dust-containing air in the raw material silo (1) into the tower (5) in sequence through the main air duct (21), the first dust removal device (3) and the connecting air duct (22). The duct assembly (2) includes a main duct (21) and a connecting duct (22). One end of the main duct (21) is connected to the exhaust port (11) through the blower (12), and the other end of the main duct (21) is connected to the air inlet of the first dust removal device (3). One end of the connecting duct (22) is connected to the air outlet of the first dust removal device (3), and the other end of the connecting duct (22) extends to the cold air inlet (51) on the bottom side wall of the tower (5). An airflow distribution plate is provided at the cold air inlet (51), and several evenly distributed ventilation holes are provided on the airflow distribution plate to allow the purified cold air to enter the tower evenly and exchange heat with the fertilizer particles. The tower (5) is provided with a feed inlet (52) at the top and a discharge outlet (53) at the bottom. A granulation device (54) is provided below the feed inlet (52). An exhaust gas outlet (55) is provided on the upper side wall of the tower (5). The exhaust gas outlet (55) is connected to the second dust removal device (4) through a pipe. The second dust removal device (4) is provided with a dust discharge outlet (56) at the bottom and an exhaust outlet (57) at the top. The exhaust outlet (57) is connected to a filter box (58) through a pipe. The exhaust outlet of the filter box (58) extends to the upper inner side of the tower (5) and is at the same height as the discharge outlet of the granulation device (54). It is used to reuse the reprocessed gas for cooling the fertilizer particles in the granulation area.

[0008] Furthermore, the first dust removal device (3) includes a settling chamber (32) and a cyclone dust collector (31) arranged in series. The inlet of the settling chamber (32) is connected to the induced draft fan (12) through a pipeline, and the outlet is connected to the inlet of the cyclone dust collector (31) through a pipeline.

[0009] Furthermore, the bottom of the cyclone dust collector (31) and the settling chamber (32) are both equipped with a discharge valve (33) and a discharge pipe (34) for periodically collecting raw material dust and realizing the recycling and reuse of raw material dust.

[0010] Furthermore, it also includes a temperature control component (6), which includes a temperature sensor (61) installed in the connecting duct (22) and a temperature control valve (62) installed on the connecting duct (22); the temperature control valve (62) is connected to an external low-temperature air source through a pipeline; when the temperature sensor (61) detects that the air temperature is higher than a preset threshold, the temperature control valve (62) opens to supplement low-temperature air and ensure that the air temperature entering the tower (5) meets the cooling process requirements.

[0011] Furthermore, a pressure balancing valve (13) is provided on the top of the raw material silo (1). When the blower (12) draws air and causes the negative pressure inside the silo to exceed the preset value, the pressure balancing valve (13) automatically opens, allowing filtered air from outside to enter the raw material silo (1) and preventing the raw material silo (1) from deforming due to excessive negative pressure.

[0012] Furthermore, the filter box (58) is equipped with a bag filter membrane for efficiently removing residual raw material dust in the exhaust gas, thereby achieving gas purification and reuse.

[0013] Compared with existing technologies, the beneficial effects of this solution are: 1. Energy saving and consumption reduction: The air in the raw material silo is used as the basic air source for the cooling air of the high tower. After dust removal, it is directly supplied without the need to draw a large amount of air from the outside and process it separately, which reduces the energy consumption of the air supply components. At the same time, the temperature of the air after dust removal is close to room temperature, so there is no need for additional deep cooling. Only a small amount of low temperature air is added when the temperature exceeds the standard, which further saves energy.

[0014] 2. Integrated functions and reduced costs: This system integrates the dust removal of raw material silos and the supply of cooling air to the high tower into one set of equipment. There is no need to configure separate exhaust and filtration equipment for the cooling air of the high tower, which reduces the number of equipment and the space occupied in the plant, and reduces the equipment purchase and operating costs.

[0015] 3. Raw material recycling to reduce waste: The raw material dust collected by the first dust removal device can be returned to the production system to avoid raw material loss caused by dust emissions and improve raw material utilization.

[0016] 4. Stable air supply and guaranteed quality: By supplementing low-temperature air through temperature control components, the temperature of the air entering the tower can be stably controlled, avoiding the impact of ambient temperature fluctuations on the fertilizer cooling effect and ensuring the quality of fertilizer products. Attached Figure Description

[0017] Figure 1 This is an overall structural diagram of the low-temperature cold air circulation supply system in the fertilizer preparation of this utility model.

[0018] In the diagram: 1-Raw material silo, 11-Exhaust vent, 12-Exhaust fan, 13-Pressure balancing valve, 2-Dust duct assembly, 21-Main duct, 22-Connecting duct, 3-First dust removal device, 31-Cyclone dust collector, 32-Settling chamber, 33-Discharge valve, 34-Discharge pipe, 4-Second dust removal device, 5-High tower, 51-Cold air inlet, 52-Feed inlet, 53-Discharge outlet, 54-Pelletizing device, 55-Waste gas emission outlet, 56-Dust outlet, 57-Exhaust outlet, 58-Filter box, 6-Temperature control component, 61-Temperature sensor, 62-Temperature control valve. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] Implementation, for example, attached Figure 1 As shown: This embodiment is a low-temperature cold air circulation supply system for fertilizer preparation, including a raw material silo 1, a duct assembly 2, a first dust removal device 3, a second dust removal device 4, and a high tower 5.

[0021] Raw material silo 1 is a vertical, sealed silo used to store the nitrogen, phosphorus, and potassium mixed raw materials for compound fertilizer. An exhaust vent 11 is provided on the silo wall of raw material silo 1, and an exhaust fan 12 is installed at the exhaust vent 11. The exhaust fan 12 is used to sequentially introduce dust-containing air from raw material silo 1 into the high tower 5 via the main air duct 21, the first dust removal device 3, and the connecting air duct 22. A pressure balancing valve 13 is installed at the top of raw material silo 1. When the exhaust fan 12 causes the negative pressure inside the silo to exceed a preset value, the pressure balancing valve 13 automatically opens, allowing filtered air from outside to enter raw material silo 1, preventing deformation of raw material silo 1 due to excessive negative pressure. The pressure balancing valve 13 is a spring-loaded pressure valve, and the preset negative pressure threshold is set according to the actual production environment, typically -5 kPa.

[0022] The duct assembly 2 includes a main duct 21 and a connecting duct 22, both made of stainless steel. One end of the main duct 21 is connected to the exhaust port 11 via an induced draft fan 12, and the other end is connected to the air inlet of the first dust removal device 3. One end of the connecting duct 22 is connected to the air outlet of the first dust removal device 3, and the other end extends to the cold air inlet 51 on the bottom side wall of the tower 5. An airflow distribution plate is provided at the cold air inlet 51. The airflow distribution plate is a perforated stainless steel plate with several evenly distributed ventilation holes. The ventilation holes have a diameter of 10 mm and a spacing of 20 mm, which are used to ensure that the purified cold air enters the tower evenly and exchanges heat with the fertilizer particles. In this scheme, the first dust removal device 3 includes a settling chamber 32 and a cyclone dust collector 31 connected in series. The inlet of the settling chamber 32 is connected to the induced draft fan 12 via a pipe, and the outlet is connected to the inlet of the cyclone dust collector 31 via a pipe for initial dust removal. Both the bottom of the cyclone dust collector 31 and the settling chamber 32 are equipped with a discharge valve 33 and a discharge pipe 34, which are used to periodically collect raw material dust. After secondary processing, the collected raw material dust is put back into the production system to realize the recycling and reuse of raw material dust.

[0023] The tower 5 has a feed inlet 52 at the top and a discharge outlet 53 at the bottom. A granulation device 54 is located below the feed inlet 52. An exhaust gas outlet 55 is located on the upper side wall of the tower 5. The exhaust gas outlet 55 is connected to the second dust removal device 4 through a pipe. The second dust removal device 4 has a dust discharge outlet 56 at the bottom and an exhaust outlet 57 at the top. The exhaust outlet 57 is connected to a filter box 58 through a pipe. The filter box 58 is equipped with a bag filter membrane, which is used to efficiently remove residual raw material dust in the exhaust gas to achieve gas purification and reuse. The exhaust outlet of the filter box 58 extends to the inner side of the upper part of the tower 5 and is at the same height as the discharge outlet of the granulation device 54. It is used to reuse the reprocessed gas for cooling fertilizer granules in the granulation area.

[0024] This system also includes a temperature control component 6, which includes a temperature sensor 61 installed inside the connecting duct 22 and a temperature control valve 62 installed on the connecting duct 22. The temperature control valve 62 is connected to an external low-temperature air source through a pipeline; when the temperature sensor 61 detects that the air temperature is higher than a preset threshold (the preset threshold can be set according to actual production conditions, generally 25℃), the temperature control valve 62 opens to supplement low-temperature air, such as low-temperature air prepared by an air-cooled refrigeration unit, to ensure that the air temperature entering the high tower 5 meets the cooling process requirements.

[0025] Working principle: When the induced draft fan 12 is started, air containing raw material dust in the raw material silo 1 enters the main air duct 21 through the exhaust port 11; the dust-laden air enters the first dust removal device 3, where the dust is trapped and falls into the settling chamber 32 and the bottom of the cyclone dust collector 31. It is periodically collected through the discharge valve 33 and discharge pipe 34. After secondary treatment, the collected raw material dust is recycled and reused in the production system; the purified air enters the connecting air duct 22, where the temperature sensor 61 monitors the air temperature in real time: if the temperature is ≤25℃, the temperature control valve 6... 2. When closed, purified air is directly and evenly introduced into the high tower 5 through the airflow distribution plate in the cold air inlet 51, where it convects and exchanges heat with the high-temperature fertilizer granules to complete the cooling. If the temperature is >25℃, the temperature control valve 62 is opened, and low-temperature outside air is introduced into the connecting air duct 22. After mixing, the air temperature drops below 25℃ and is then introduced into the high tower cooling zone 5. When the induced draft fan 12 draws air from the raw material silo 1, causing the negative pressure inside the silo to drop below -5kPa, the pressure balancing valve 13 is opened, and outside air enters the raw material silo 1 after being filtered by the filter screen, maintaining stable and safe pressure inside the silo. The exhaust gas generated during the cooling process enters the second dust removal device 4 through the exhaust port 55 for dust removal treatment. The dust-removed gas is discharged through the exhaust port 57, enters the interior above the high tower 5 through the filter box 58, and after being filtered again, the gas enters the high tower 5 to convectively cool the fertilizer granules produced by the granulation device 54.

[0026] This system integrates dust removal and cooling air supply functions, reducing the number of equipment and energy consumption, lowering costs, stabilizing cooling air temperature, ensuring fertilizer quality, and recovering raw material dust to reduce waste.

[0027] The above descriptions are merely embodiments of this utility model, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of this utility model, and these should also be considered within the scope of protection of this utility model. These modifications will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application shall be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A low-temperature cold air circulation supply system for fertilizer preparation, comprising a raw material silo (1), a duct assembly (2), a first dust removal device (3), a second dust removal device (4), and a high tower (5), characterized in that: The raw material silo (1) has an exhaust vent (11) on its wall. An exhaust fan (12) is installed at the exhaust vent (11). The exhaust fan (12) is used to introduce the dust-containing air in the raw material silo (1) into the tower (5) in sequence through the main air duct (21), the first dust removal device (3) and the connecting air duct (22). The duct assembly (2) includes a main duct (21) and a connecting duct (22). One end of the main duct (21) is connected to the exhaust port (11) through the blower (12), and the other end of the main duct (21) is connected to the air inlet of the first dust removal device (3). One end of the connecting duct (22) is connected to the air outlet of the first dust removal device (3), and the other end of the connecting duct (22) extends to the cold air inlet (51) on the bottom side wall of the tower (5). An airflow distribution plate is provided at the cold air inlet (51), and several evenly distributed ventilation holes are provided on the airflow distribution plate to allow the purified cold air to enter the tower evenly and exchange heat with the fertilizer particles. The tower (5) is provided with a feed inlet (52) at the top and a discharge outlet (53) at the bottom. A granulation device (54) is provided below the feed inlet (52). An exhaust gas outlet (55) is provided on the upper side wall of the tower (5). The exhaust gas outlet (55) is connected to the second dust removal device (4) through a pipe. The second dust removal device (4) is provided with a dust discharge outlet (56) at the bottom and an exhaust outlet (57) at the top. The exhaust outlet (57) is connected to a filter box (58) through a pipe. The exhaust outlet of the filter box (58) extends to the upper inner side of the tower (5) and is at the same height as the discharge outlet of the granulation device (54). It is used to reuse the reprocessed gas for cooling the fertilizer particles in the granulation area.

2. The low-temperature cold air circulation supply system for fertilizer preparation according to claim 1, characterized in that: The first dust removal device (3) includes a settling chamber (32) and a cyclone dust collector (31) arranged in series. The inlet of the settling chamber (32) is connected to the induced draft fan (12) through a pipeline, and the outlet is connected to the inlet of the cyclone dust collector (31) through a pipeline.

3. The low-temperature cold air circulation supply system for fertilizer preparation according to claim 2, characterized in that: The bottom of both the cyclone dust collector (31) and the settling chamber (32) is equipped with a discharge valve (33) and a discharge pipe (34) for periodically collecting raw material dust and realizing the recycling and reuse of raw material dust.

4. The low-temperature cold air circulation supply system for fertilizer preparation according to claim 1, characterized in that: It also includes a temperature control component (6), which includes a temperature sensor (61) installed in the connecting duct (22) and a temperature control valve (62) installed on the connecting duct (22). The temperature control valve (62) is connected to an external low-temperature air source through a pipeline. When the temperature sensor (61) detects that the air temperature is higher than a preset threshold, the temperature control valve (62) opens to supplement low-temperature air and ensure that the air temperature entering the tower (5) meets the cooling process requirements.

5. The low-temperature cold air circulation supply system for fertilizer preparation according to claim 1, characterized in that: The top of the raw material silo (1) is equipped with a pressure balancing valve (13). When the blower (12) draws air and causes the negative pressure inside the silo to exceed the preset value, the pressure balancing valve (13) automatically opens, allowing filtered air from outside to enter the raw material silo (1) and preventing the raw material silo (1) from deforming due to excessive negative pressure.

6. The low-temperature cold air circulation supply system for fertilizer preparation according to claim 1, characterized in that: The filter box (58) is equipped with a bag filter membrane, which is used to efficiently remove residual raw material dust in the exhaust gas and realize gas purification and reuse.

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