Fertilizer preparation device integrating drying, cooling and screening

Abstract

The invention relates to the technical field of fertilizer production, in particular to a fertilizer preparation device integrating drying, cooling and screening. The device comprises a screening box, a first treatment barrel and a second treatment barrel are connected to the lower portion of the screening box, a screening structure and a dust removal structure are arranged in the screening box, and a movable partition structure is arranged in the middle of the interior of the first treatment barrel and divides the interior of the first treatment barrel into an upper drying cavity and a lower cooling cavity. The first treatment cylinder and the second treatment cylinder are the same in internal structure, and normal-temperature air inlet pipes connected into the two drying cavities are arranged in front of the first treatment cylinder and the second treatment cylinder. The cooling cavity is connected with a low-temperature air inlet pipe; a heat recovery device is arranged on the normal-temperature air inlet pipe; the integrated design is adopted, the three internal areas are relatively independent, the internal temperatures of the three internal areas can be kept relatively stable, and energy consumption is reduced; the heat recovery device is designed, gas heat energy is recycled, so that energy needed by equipment heating is greatly reduced, and energy conservation and environment protection are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fertilizer production, in particular to a fertilizer preparation device integrating drying, cooling and screening. BACKGROUND

[0002] As the "food" of food, fertilizer is used in agricultural production to provide plants with the required nutrients while providing special properties such as soil modification. Traditional fertilizer production processes usually separate drying, cooling and screening processes, resulting in large equipment footprint, complex process flow, high energy consumption and low production efficiency. In recent years, some integrated devices have appeared that can perform the above processes on fertilizer particles using a single device. However, the internal chambers of the integrated device are independent, and heating, drying, cooling and screening must be completed in the chambers. The temperature changes during heating and cooling result in a large amount of heat loss, causing waste and high energy consumption for reheating at low temperatures. SUMMARY

[0003] The present application aims to overcome the deficiencies of the prior art and provide a fertilizer preparation device integrating drying, cooling and screening, which can solve the above-mentioned problems.

[0004] To achieve the above-mentioned purposes, the present application adopts the following technical scheme: it includes a screening box, a processing cylinder one and a processing cylinder two connected below the screening box, a spiral feeder connected to the screening box installed on the side of the processing cylinder one and the processing cylinder two, a valve-equipped discharge pipe for discharging connected to the bottom of the processing cylinder one and the processing cylinder two, a screening structure and a dust removal structure provided in the screening box, a movable partition structure provided in the middle of the processing cylinder one, which divides the processing cylinder one into a drying chamber above and a cooling chamber below, the internal structures of the processing cylinder one and the processing cylinder two are the same, a normal temperature air inlet pipe connected to the two drying chambers is provided in front of the processing cylinder one and the processing cylinder two, and heating wires are provided at the connection between the normal temperature air inlet pipe and the two drying chambers; the cooling chamber is connected to a low temperature air inlet pipe connected to an external low temperature drying gas supply device, and the normal temperature air inlet pipe is connected to an external clean gas device; a heat recovery device is provided on the normal temperature air inlet pipe.

[0005] Preferably, the heat recovery device includes a heat exchanger one provided in front of the drying chamber, the drying chamber is connected to the heat exchanger one through an air outlet pipe on the side opposite to the normal temperature air inlet pipe, the heat exchanger one has a curved heat exchange channel one and a curved heat exchange channel two, the normal temperature air inlet pipe is disconnected in the middle and connected to the two ports of the heat exchange channel one, and the air outlet pipe of the drying chamber is connected to the heat exchange channel two.

[0006] Preferably, the heat exchanger is provided with a heat exchanger two behind, the structure of the heat exchanger two is the same as that of the heat exchanger one, the rear half of the normal temperature air inlet pipe is disconnected and connected to the two ports of the heat exchange air duct two of the heat exchanger two respectively, the heat exchanger two is provided with a heat pump on the side, the outlet end of the heat exchange air duct two of the heat exchanger one is connected to the heat pump, the exhaust port of the heat pump is connected with an exhaust pipe, and the heat output circulation pipeline of the heat pump is connected to the heat exchange air duct two of the heat exchanger two.

[0007] Preferably, a pipeline for exhaust is connected to the side opposite to the low-temperature air inlet pipe on the cooling cavity, the pipeline is connected with a switching valve, the switching valve is a three-way switching valve, and the two outlet ends of the three-way switching valve are connected to the exhaust pipe and the pipeline between the heat exchanger one and the heat pump through the pipeline respectively.

[0008] Preferably, the movable separation structure comprises a disc-shaped fixed plate fixed to the middle part of the processing cylinder one, a plurality of discharging grooves are formed in the fixed plate, a movable plate is rotatably installed below the fixed plate, a plurality of discharging grooves identical to those in the fixed plate are formed in the movable plate, a control motor is installed on the inner wall of the processing cylinder one, a control gear is connected to the movable end of the control motor, an arc-shaped rack is arranged at the outer edge of the bottom of the movable plate, and the control gear is engaged with the arc-shaped rack.

[0009] Preferably, temperature sensors are arranged in the drying cavity and the cooling cavity respectively.

[0010] Preferably, the screening structure comprises a screen plate obliquely installed in a screening box, a vibration motor is arranged below the screen plate, a plurality of buffers are installed on the bottom of the screen plate, the outlet end of the spiral feeder is arranged above the higher end of the screen plate, two feed pipes are connected to the bottom of the screening box, the bottom ends of the two feed pipes are connected to the processing cylinder one and the processing cylinder two respectively, a discharging hopper is arranged below the screen plate and in front of the screen plate respectively, and the bottom ends of the two discharging hoppers are connected to the two feed pipes respectively.

[0011] Preferably, the dust removal structure comprises two baffle plates embedded in the two sides of the screening box, a plurality of holes are formed in the baffle plates, the sizes of the holes are smaller than the minimum size of the fertilizer particles, dust suction heads are arranged on the outer sides of the baffle plates on the two sides of the screening box, a dust collector is arranged on the side of the processing cylinder one, the dust collector is connected to the two dust suction heads through air pipes, and a plurality of air holes for air inlet are formed in the top of the screening box.

[0012] Preferably, rotating shafts are rotatably installed at the centers of the processing cylinder one and the processing cylinder two respectively, a plurality of groups of stirring blades are arranged on the rotating shafts in the drying cavity and the cooling cavity, a driving motor is installed on the processing cylinder two, a speed reducer is connected to the driving motor, and the output end of the speed reducer is drivingly connected to the two rotating shafts through a chain wheel assembly.

[0013] Preferably, a control plate is slidably arranged in the horizontal direction in each of the processing barrel one and the processing barrel two, and the control plate is arranged at the lower side of the inlet pipe; an extension cylinder is arranged on the outer side of the processing barrel one and the processing barrel two, and the movable end of the extension cylinder is connected to the control plate.

[0014] After the above structure is adopted, the beneficial effects of the present application are: The present application adopts an integrated design, in which the spiral feeder uniformly feeds materials, and then the materials are screened by a vibrating screen, dusted, dried and cooled; the three areas are relatively independent, and the working process is closed, the influence between the areas is small, the internal temperature of each area is relatively stable, and the energy consumption is reduced.

[0015] The present application designs a heat recovery device, which recycles the high-temperature gas in the initial drying and cooling stage, especially, the high-temperature gas in the drying stage is subjected to twice heat exchange, and the heat is used for preheating the newly-incoming gas, so that the energy required for heating the equipment is greatly reduced, the temperature of the discharged gas is reduced, and energy saving and environmental protection are achieved. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a front side structure schematic diagram of the present application; Figure 2 is a right side structure schematic diagram of the present application; Figure 3 is Figure 2 is an enlarged view of A part in the present application; Figure 4 is a right rear structure schematic diagram of the present application; Figure 5 is a principle schematic diagram of the heat recovery device in the present application; Figure 6 is a cross-sectional view of the processing barrel one, the processing barrel two and the screening box in the present application; Figure 7 is a bottom view of the movable partition structure in the present application; Figure 8 is a structure schematic diagram when the fixed plate and the movable plate are closed in the present application; Figure 9 is a cross-sectional view of the heat exchanger one in the present application.

[0017] Explanation of reference signs: 1, spiral feeder; 2, screening box; 3, sieve plate; 4, vibration motor; 5, buffer; 6, discharge funnel; 7, feed pipe; 8, processing cylinder one; 9, processing cylinder two; 10, baffle; 11, dust suction head; 12, dust collector; 13, drive motor; 14, speed reducer; 15, chain wheel assembly; 16, rotating shaft; 17, stirring blade; 18, fixed plate; 19, movable plate; 20, discharge slot; 21, control motor; 22, arc-shaped rack; 23, control gear; 24, air hole; 25, normal temperature air inlet pipe; 26, heat exchanger one; 27, heat exchanger two; 28, heat exchange air duct one; 29, heat exchange air duct two; 30, heat pump; 31, switching valve; 32, temperature sensor; 33, exhaust pipe; 34, low temperature air inlet pipe; 35, discharge pipe; 36, control panel; 37, telescopic cylinder. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0019] Referring to Figures 1-6 As shown in the figure, it comprises an efficient screening box 2, and the screening box 2 is connected with a processing cylinder one 8 and a processing cylinder two 9 below, the side surfaces of the two processing cylinders are provided with a spiral feeder 1 for uniform feeding; the bottom of the processing cylinder one 8 and the processing cylinder two 9 are both provided with a discharge pipe 35 with a valve for facilitating the discharge of materials; the inside of the screening box 2 is provided with a screening structure and a dust removal structure to ensure that the materials are screened efficiently and environmentally friendly; the middle part of the processing cylinder one 8 is provided with a movable partition structure, which divides the processing cylinder one 8 into a drying cavity in the upper part and a cooling cavity in the lower part; the internal structures of the processing cylinder one 8 and the processing cylinder two 9 are the same, and both are provided with a normal temperature air inlet pipe 25 connected to the two drying cavities in front, and the connection between the air inlet pipe and the drying cavity is provided with a heating wire to provide necessary drying heat; the cooling cavity is connected with a low temperature air inlet pipe 34 connected to an external low temperature drying air supply equipment, while the normal temperature air inlet pipe 25 is connected to an external clean air equipment to ensure that the gas entering the system is clean and pollution-free; the normal temperature air inlet pipe 25 is provided with a heat recovery device to improve energy utilization efficiency.

[0020] Referring to Figures 1-9As shown, the heat recovery device comprises a heat exchanger 26 arranged in front of the drying chamber, the drying chamber is connected to the heat exchanger 26 through the air outlet pipeline on the side opposite to the normal temperature air inlet pipe 25, the heat exchanger 26 is respectively provided with a curved heat exchange air channel 28 and a heat exchange air channel 29, the middle part of the normal temperature air inlet pipe 25 is disconnected and respectively connected to the two ports of the heat exchange air channel 28, and the air outlet pipeline of the drying chamber is connected to the heat exchange air channel 29; The heat exchanger 26 is provided with a heat exchanger 27 behind it, which has the same structure as the heat exchanger 26, the rear half of the normal temperature air inlet pipe 25 is disconnected and respectively connected to the two ports of the heat exchange air channel 29 of the heat exchanger 27, and the heat pump 30 is arranged on the side of the heat exchanger 27, the heat pump 30 is a high-temperature heat pump 30, the outlet end of the heat exchange air channel 29 of the heat exchanger 26 is connected to the heat pump 30, the exhaust port of the heat pump 30 is connected to the exhaust pipe 33, and the heat output circulation pipeline of the heat pump 30 is connected to the heat exchange air channel 29 of the heat exchanger 27, forming an efficient heat recovery circulation system; the cooling chamber is connected to a pipeline for exhaust on the side opposite to the low-temperature air inlet pipe 34, the pipeline is connected to a switching valve 31, the switching valve 31 is a three-way switching valve 31, the two outlet ends of the three-way switching valve 31 are respectively connected to the exhaust pipe 33 and the pipeline between the heat exchanger 26 and the heat pump 30 through the pipeline, so as to realize flexible control and discharge of the gas; the drying chamber and the cooling chamber are respectively provided with temperature sensors 32, so as to realize real-time monitoring and adjustment of the temperature in the chamber, and ensure the best effect of the material processing process.

[0021] The high-temperature gas entering the drying chamber is discharged as exhaust gas, and then enters the heat exchanger 26, directly conducts heat to the gas flowing in the normal temperature air inlet pipe 25, and preliminarily preheats the gas, and the temperature of the exhaust gas discharged from the heat exchanger 26 is greatly reduced compared with that before entering the heat exchanger 26, so that the heat of the exhaust gas is further extracted by the heat pump 30, and the heat is concentrated by circulating water or steam, and then the heat is conducted to the gas entering the drying chamber through the heat exchanger 27 again, so that the gas has been double-preheated when contacting the heating wire, the heating power required by the heating wire is greatly reduced, and the heat of the exhaust gas has been recovered in a large amount, so that the exhaust gas is directly discharged through the exhaust pipe 33; At the same time, after the gas enters the cooling chamber, the temperature of the gas is relatively high in the initial period of time due to the high temperature of the particulate matter after drying, so that the exhaust gas also contains a certain amount of heat energy, and the temperature sensor 32 in the cooling chamber can detect the temperature, when the temperature is relatively high and has recovery value, the switching valve 31 is connected to the heat pump 30, and the gas in the cooling chamber is not actively heated, so the temperature is lower than that of the gas directly discharged from the drying chamber, so the gas in the cooling chamber is mixed with the gas discharged from the heat exchanger 26, and the heat energy is recovered by the heat pump 30; when the temperature of the cooling chamber is relatively low, the switching valve 31 is switched to the exhaust pipe 33, and the gas is directly discharged.

[0022] Referring to Figures 1-7 As shown, the movable partition structure comprises a disc-shaped fixed plate 18 fixed at a middle position in the processing cylinder 1, a plurality of discharging slots 20 are formed on the fixed plate 18, a movable plate 19 is rotatably installed below the fixed plate 18, a plurality of discharging slots 20 are formed on the movable plate 19, a control motor 21 is installed on the inner wall of the processing cylinder 1, a control gear 23 is connected to the movable end of the control motor 21, an arc-shaped rack 22 is arranged at the outer edge of the bottom of the movable plate 19, and the control gear 23 is engaged with the arc-shaped rack 22 to realize accurate control of the movable plate 19.

[0023] By controlling the control motor 21, the movable plate 19 is driven to rotate by the gear and the arc-shaped rack 22. When the discharging slots 20 of the movable plate 19 and the fixed plate 18 are aligned, the fertilizer particles can fall through the discharging slots 20. When the two are misaligned, for example Figure 8 As shown, the discharging slots 20 are closed, and the drying chamber and the cooling chamber are relatively closed.

[0024] Referring to Figures 1-6 As shown, the screening structure comprises a screen plate 3 obliquely installed in the screening box 2, a vibration motor 4 is arranged below the screen plate 3, a plurality of buffers 5 are installed at the bottom of the screen plate 3 to reduce the impact force generated by material vibration, the outlet end of the screw feeder 1 is arranged above the higher end of the screen plate 3, two feed pipes 7 are connected to the bottom of the processing cylinder 1 and the processing cylinder 2, respectively, a discharging hopper 6 is arranged below the screen plate 3 and in front of the lower side of the screen plate 3, respectively, and the bottom of the two discharging hoppers 6 is connected to the two feed pipes 7, respectively, to ensure that the material can smoothly enter the processing cylinder.

[0025] Referring to Figures 1-6 As shown, the dust removal structure comprises two baffle plates 10 embedded on both sides of the screening box 2, a plurality of holes are formed on the baffle plates 10, and the size of the holes is smaller than the minimum size of the fertilizer particles, a dust suction head 11 is arranged on the outer side of the baffle plate 10 on both sides of the screening box 2, a dust collector 12 is arranged beside the processing cylinder 1, and the dust collector 12 is connected to the two dust suction heads 11 through an air pipe to effectively remove the dust generated during the screening process; a plurality of air holes 24 are formed on the top of the screening box 2 for air intake, to ensure air circulation inside the system and stable air pressure.

[0026] Referring to Figures 1-6As shown, a rotating shaft 16 is rotatably installed at the center of processing cylinder 8 and processing cylinder 9 respectively. Multiple sets of stirring blades 17 are provided on the rotating shaft 16 in the drying chamber and cooling chamber to ensure that the material is uniformly heated and cooled during the processing. A drive motor 13 is installed on processing cylinder 9, and a reducer 14 is connected to the drive motor 13. The output end of the reducer 14 is connected to the two rotating shafts 16 through a sprocket assembly 15 to achieve efficient driving of the rotating shafts 16. A control plate 36 is slidably installed in processing cylinder 8 and processing cylinder 9 in the horizontal direction. The control plate 36 is located at the lower opening of the feed pipe 7. Telescopic cylinders 37 are installed on the outer side of processing cylinder 8 and processing cylinder 9 respectively. The movable end of the telescopic cylinder 37 is connected to the control plate 36 to control the flow of material and keep the drying chamber relatively closed during the operation.

[0027] The usage process of this invention: First, the equipment is started to feed fertilizer granules through the screw feeder 1. The screw feeder 1 feeds the material into the screening box 2 at a uniform speed. Under the action of vibration, the granules are screened. At the same time, because the granules are suspended in the air and vibrate during the falling process, the dust mixed in with the granules will be raised and sucked out by the airflow and removed by the dust collector 12. The granules are then screened according to size and enter the processing cylinder 1 8 and processing cylinder 2 9 respectively. After a batch of feeding is completed, the control board 36 is closed, and the drying chamber is sealed. The drive motor 13 drives the rotating shaft 16 to rotate, which drives the stirring blade 17 to stir the granules. The gas is input from the ambient temperature air inlet pipe 25 and heated, so that the temperature in the drying chamber rises. As the temperature rises, the heat exchanger 1 26, the heat pump 30, and the heat exchanger 2 27 start to work to recover the heat of the waste gas. The heating wire controls the power in real time according to the temperature of the drying chamber. As the usage time increases, the heating power consumption of the equipment will gradually decrease until it stabilizes. After the particles in the drying chamber are processed, the drive motor 13 stops working, the control motor 21 starts, and the particles fall from the feeding slot 20 into the cooling chamber. Then the control plate 36 opens, and the upper drying chamber is fed again. Then the drive motor 13 starts, and the drying chamber and cooling chamber operate synchronously. The gas discharged from the cooling chamber is also recovered until the temperature drops to the threshold. The switching valve 31 automatically switches, and the gas discharged from the cooling chamber stops being recovered. After a certain period of time, both the cooling chamber and the drying chamber have completed their work. At this time, the discharge pipe 35 opens, the equipment discharges the particles, and the valve closes. Then the movable plate 19 rotates and opens, and the particles in the drying chamber are discharged. The screw feeder 1 starts feeding again, thus enabling continuous operation. Therefore, the drying chamber is not affected by cooling, and the overall internal temperature can be maintained within a certain range, reducing energy loss.

[0028] It should be understood that the foregoing detailed description of the application, rather than limiting the application, is intended to explain and describe the current implementation of the application. Therefore, any modification, equivalent replacement or improvement made without departing from the spirit and scope of the application should be included in the protection scope of the application. In addition, the appended claims of the application are intended to cover all changes and modifications falling within the scope and boundary of the appended claims, or the equivalent form of such scope and boundary.

Claims

1. A fertilizer production plant combining drying, cooling and sieving in one, comprising a sieving box (2), characterized in that: The screening box (2) is connected with a processing cylinder I (8) and a processing cylinder II (9) below, the side of the processing cylinder I (8) and the processing cylinder II (9) is provided with a screw feeder (1) connected to the screening box (2), the bottom of the processing cylinder I (8) and the processing cylinder II (9) is connected with a valve-equipped discharge pipe (35) for discharging, the screening box (2) is provided with a screening structure and a dust removal structure, the middle of the processing cylinder I (8) is provided with a movable separation structure, the movable separation structure divides the processing cylinder I (8) into a drying cavity above and a cooling cavity below, the internal structure of the processing cylinder I (8) and the processing cylinder II (9) is the same, the front of the processing cylinder I (8) and the processing cylinder II (9) is provided with a normal-temperature air inlet pipe (25) connected to two drying cavities, the connection between the normal-temperature air inlet pipe (25) and the two drying cavities is provided with a heating wire; the cooling cavity is connected with a low-temperature air inlet pipe (34), the low-temperature air inlet pipe (34) is connected to an external low-temperature drying air supply equipment, and the normal-temperature air inlet pipe (25) is connected to an external clean air equipment; the normal-temperature air inlet pipe (25) is provided with a heat recovery device.

2. A fertilizer manufacturing unit incorporating drying, cooling and screening in one, as claimed in claim 1, wherein: The heat recovery device comprises a heat exchanger I (26) arranged in front of the drying cavity, the drying cavity is connected to the heat exchanger I (26) through an air outlet pipeline on the side opposite to the normal-temperature air inlet pipe (25), the heat exchanger I (26) is respectively provided with a curved heat exchange air channel I (28) and a heat exchange air channel II (29), the middle of the normal-temperature air inlet pipe (25) is disconnected and connected to two ports of the heat exchange air channel I (28), and the air outlet pipeline of the drying cavity is connected to the heat exchange air channel II (29).

3. A fertilizer manufacturing unit incorporating drying, cooling and screening in one, as claimed in claim 2, wherein: The heat exchanger I (26) is provided with a heat exchanger II (27) behind, the structure of the heat exchanger II (27) is the same as that of the heat exchanger I (26), the rear half of the normal-temperature air inlet pipe (25) is disconnected and connected to two ports of the heat exchange air channel II (29) of the heat exchanger II (27), the heat exchanger II (27) is provided with a heat pump (30) on the side, the outlet end of the heat exchange air channel II (29) of the heat exchanger I (26) is connected to the heat pump (30), the exhaust port of the heat pump (30) is connected with an exhaust pipe (33), and the heat output circulation pipeline of the heat pump (30) is connected to the heat exchange air channel II (29) of the heat exchanger II (27).

4. A fertilizer manufacturing plant integrating drying, cooling and screening, according to claim 3, characterized in that: The side opposite to the low-temperature air inlet pipe (34) of the cooling cavity is connected with a pipeline for exhausting air, the pipeline is connected with a switching valve (31), the switching valve (31) is a three-way switching valve (31), two outlet ends of the three-way switching valve (31) are connected to the exhaust pipe (33) and the pipeline between the heat exchanger I (26) and the heat pump (30) through pipelines.

5. A fertilizer manufacturing unit incorporating drying, cooling and screening in one, as claimed in claim 1, wherein: The movable separation structure comprises a disc-shaped fixed plate (18) fixed to a middle position in the processing cylinder (8), a plurality of discharging slot holes (20) are formed in the fixed plate (18), a movable plate (19) is rotatably arranged below the fixed plate (18), a plurality of discharging slot holes (20) identical to those in the fixed plate (18) are formed in the movable plate (19), a control motor (21) is arranged on the inner wall of the processing cylinder (8), a control gear (23) is connected to the movable end of the control motor (21), an arc-shaped gear rack (22) is arranged at the outer edge of the bottom of the movable plate (19), and the control gear (23) is engaged with the arc-shaped gear rack (22).

6. A fertilizer manufacturing unit incorporating drying, cooling and screening in one as claimed in claim 1, wherein: Temperature sensors (32) are arranged in the drying cavity and the cooling cavity respectively.

7. A fertilizer manufacturing unit incorporating drying, cooling and screening in one, as claimed in claim 1, wherein: The screening structure comprises a screen plate (3) obliquely arranged in a screening box (2), a vibration motor (4) is arranged below the screen plate (3), a plurality of buffers (5) are arranged on the bottom of the screen plate (3), the outlet end of the spiral feeder (1) is arranged above the higher end of the screen plate (3), two feed pipes (7) are connected to the bottom of the processing cylinder (8) and the processing cylinder (9) respectively, a discharging hopper (6) is arranged below the screen plate (3) and in front of the screen plate (3) respectively, and the bottom of the two discharging hoppers (6) is connected to the two feed pipes (7) respectively.

8. A fertilizer manufacturing unit incorporating drying, cooling and screening in one as claimed in claim 1, wherein: The dust removal structure comprises two baffle plates (10) arranged at the two sides of the screening box (2), a plurality of holes are formed in the baffle plates (10), the size of the holes is smaller than the minimum size of the fertilizer particles, dust suction heads (11) are arranged at the positions outside the baffle plates (10) at the two sides of the screening box (2), a dust collector (12) is arranged at the side of the processing cylinder (8), the dust collector (12) is connected to the two dust suction heads (11) through air pipes, and a plurality of air holes (24) for air inlet are formed in the top of the screening box (2).

9. A fertilizer manufacturing unit incorporating drying, cooling and screening in one as claimed in claim 1, wherein: Rotating shafts (16) are rotatably arranged at the centers of the processing cylinder (8) and the processing cylinder (9) respectively, a plurality of groups of stirring blades (17) are arranged on the rotating shafts (16) in the drying cavity and the cooling cavity, a driving motor (13) is arranged on the processing cylinder (9), a speed reducer (14) is connected to the driving motor (13), and the output end of the speed reducer (14) is drivingly connected to the two rotating shafts (16) through a chain wheel assembly (15).

10. A fertilizer manufacturing plant integrating drying, cooling and screening, according to claim 7, characterized in that: Control plates (36) are slidingly arranged in the processing cylinder (8) and the processing cylinder (9) respectively along the horizontal direction, the control plates (36) are arranged at the lower side of the feed pipe (7), telescopic cylinders (37) are arranged at the outer sides of the processing cylinder (8) and the processing cylinder (9) respectively, and the movable ends of the telescopic cylinders (37) are connected to the control plates (36).

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