A heat treatment-free composite fertilizer preparation process and system

Abstract

This invention discloses a heat-free compound fertilizer preparation process and system, relating to the field of compound fertilizer technology. The preparation process includes the following steps: S1, weighing nitrogen, phosphorus, and potassium raw materials according to the formula, mixing and grinding them with alkaline materials to obtain powdered materials; S2, a feeding auger delivers the powdered materials to a drum, where they are carried to a high point and scattered by a pusher in the rotating drum. In this invention, liquid sulfuric acid is atomized and sprayed through a nozzle. Powdered materials are sprayed from above the spraying area and collide with and mix with the sulfuric acid. The sulfuric acid reacts with the alkaline materials in the powdered materials to generate moisture and heat. The moisture initially "binds" the powder to form agglomerates. These agglomerates roll along the inner wall of the drum as it rotates, adhering to more powder and gradually forming small particles. The heat generated by the neutralization reaction raises the internal temperature of the drum, accelerating the evaporation of moisture from the particles and drying them to prevent particle sticking.

Description

Technical Field

[0001] This invention relates to the field of compound fertilizer technology, specifically to a heat-free compound fertilizer preparation process and system. Background Technology

[0002] As is generally known, compound fertilizers are made by mixing two or more chemical fertilizers. They have high nutrient content and fertilizer efficiency, and can meet the different nutrient needs of different plants while reducing fertilization costs, making them a relatively economical and efficient fertilization method. Common types of compound fertilizers include diammonium phosphate, monoammonium phosphate, binary compound fertilizers, and ternary compound fertilizers.

[0003] For example, the utility model patent with application publication number CN208824434U, application publication date May 7, 2019, entitled "A Compound Fertilizer Drum Granulator," includes a drum body, a power unit, drum support rollers, and a frame. Its key feature is that the drum body comprises a shell and a granulation drum located inside the shell. A sandwich channel is provided between the granulation drum and the shell, and the outlet of the sandwich channel is connected to the outlet of the granulation drum. The granulation drum is provided with a powder inlet and a liquid inlet pipe. Several nozzles are evenly distributed along the circumference at the outlet end of the liquid inlet pipe. Multiple granulation zones are provided inside the granulation drum, and adjacent granulation zones are separated by a screen. A granulated fertilizer outlet, automatically closed by a telescopic plate, is provided on the inner wall of each granulation zone, and the granulated fertilizer outlet is connected to the interior of the sandwich channel. This utility model has a simple structure, high granulation efficiency, and effectively reduces raw material loss.

[0004] The shortcomings of existing technologies lie in the fact that compound fertilizer production requires first weighing and crushing the raw materials into powder and mixing them. The mixture is then fed into a granulator, where a small amount of water or binder solution is sprayed in, causing the fine powder to wet, collide, and adhere during rolling, forming moist granules. These moist granules are then fed into a fluidized bed, where excess moisture is dried, and the granules are cooled again to prevent clumping. Finally, qualified granules are screened for packaging. However, this production method requires a hot air furnace outside the production equipment to heat the fluidized bed, thereby drying the granules and preventing adhesion, resulting in high production costs and cumbersome steps. Summary of the Invention

[0005] The purpose of this invention is to provide a heat-free compound fertilizer preparation process and system to overcome the above-mentioned shortcomings in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a heat-free compound fertilizer preparation process, comprising the following steps:

[0007] S1. Weigh nitrogen, phosphorus, and potassium raw materials according to the formula, mix and grind them with alkaline materials to obtain powder materials;

[0008] S2. The feeding auger delivers the powdered material into the drum, where it is carried to a high point and scattered by the pusher in the rotating drum.

[0009] S3. Add sulfuric acid material to the drum. The sprinkled powder mixes with the sulfuric acid material. The sulfuric acid material and the alkaline powder undergo a neutralization reaction to generate water and heat. The powder is moistened by water and clumps into particles in the drum. The heat dries the excess water.

[0010] S4. The particles are discharged from the outlet, and after being screened, they are measured and packaged.

[0011] A heat-free compound fertilizer preparation system, used to implement the heat-free compound fertilizer preparation process in the above-mentioned scheme, includes a frame, on which are arranged:

[0012] A closed-end roller with its discharge port located on the side wall is rotatably mounted on the frame. A pusher extending along a spiral is provided on the inner wall of the roller, and a storage trough is provided on the top plate of the pusher.

[0013] An installation cylinder is fixedly mounted on the frame and its end extends into the interior of the drum. The interior of the installation cylinder is equipped with a feeding auger and an atomizing nozzle, wherein:

[0014] The pusher rotates with the roller to deliver material from above the atomizing nozzle spray area through the storage trough.

[0015] As a further description of the above technical solution: the inside of the roller is provided with a plurality of guides arranged in sequence and in the same spiral direction as the pusher, and the tail end of the innermost guide is directly opposite the discharge port.

[0016] As a further description of the above technical solution: the slope of the pusher and the top plates of the multiple guides decreases sequentially.

[0017] As a further description of the above technical solution: the interior of the mounting cylinder is provided with a return feeder that is distributed opposite to the feeder and has the opposite spiral direction.

[0018] As a further description of the above technical solution: the inside of the roller is provided with a pair of stop blocks that correspond to the pusher and the outermost guide, respectively.

[0019] As a further description of the above technical solution: the cross-section of the stop block is a right triangle, the hypotenuse is parallel to the end of the roller, and the side edge faces the outside of the roller.

[0020] As a further description of the above technical solution: the atomizing nozzle on the mounting cylinder is tilted upwards at an angle.

[0021] As a further description of the above technical solution: both the pusher and the guide are provided with striking blocks distributed along a spiral array inside.

[0022] As a further description of the above technical solution: the plurality of striking blocks move as the roller rotates and collide with the inner wall of the corresponding pusher or guide in sequence.

[0023] In the above technical solution, the present invention provides a heat-free compound fertilizer preparation process and system, which has the following beneficial effects: During operation, the feeding auger delivers powdered material into the drum. The rotating drum, through a pusher, moves the powdered material upward and, through a storage trough, delivers the dry powdered material to a higher position. Liquid sulfuric acid is atomized and sprayed out through nozzles. The atomized sulfuric acid gathers in the spraying area, while the powdered material falls and disperses from above. The atomized sulfuric acid collides and mixes with the falling dry powder, making the dry powder wet. Furthermore, the sulfuric acid neutralizes the alkaline substances in the powdered material, generating moisture and heat. Moisture forms between the contact points of the powder particles. The "liquid bridge" generates surface tension, initially "binding" the powder together to form agglomerates. Then, the agglomerates roll along the inner wall of the drum as it rotates, adhering to more powder and gradually forming smaller particles. The heat generated by the neutralization reaction raises the internal temperature of the drum, accelerating the evaporation of moisture in the particles and drying them to prevent them from sticking together. The drum continues to rotate, and the storage trough on the pusher lifts the small particles and powder together and moves along the inclined storage trough. Since the particles have a greater ability to roll along the slope than the powder, most of the particles and a small portion of the powder will move directly along the inclined pusher towards the inside of the drum, while most of the powder will gather and remain in the storage trough and continue to move with the pusher to a higher point, where it will come into contact with the mist-like sulfuric acid again. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0025] Figure 1 This is a schematic diagram of the overall structure provided in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the bottom structure provided in an embodiment of the present invention;

[0027] Figure 3 A schematic diagram of the side structure of the roller provided in an embodiment of the present invention;

[0028] Figure 4 This is a schematic diagram of the internal structure of the drum provided in an embodiment of the present invention;

[0029] Figure 5 This is a schematic diagram of the structure of the recycle feeder provided in an embodiment of the present invention;

[0030] Figure 6 This is a schematic diagram of the pusher and guide provided in an embodiment of the present invention;

[0031] Figure 7 This is a schematic diagram of the cross-section of the feeder provided in an embodiment of the present invention;

[0032] Figure 8 A schematic cross-sectional view of the sliding sleeve provided in an embodiment of the present invention;

[0033] Figure 9 This is a schematic cross-sectional view of the pusher provided in an embodiment of the present invention;

[0034] Figure 10 A flowchart for compound fertilizer production provided in an embodiment of the present invention.

[0035] Explanation of reference numerals in the attached figures:

[0036] 1. Frame; 11. Roller; 111. Pusher; 112. Guide; 113. Returner; 114. Storage trough; 115. Discharge port; 116. Stop block; 12. Mounting cylinder; 121. Feeding auger; 122. Atomizing nozzle; 123. Spraying area; 13. Striking block; 131. Fixing rod; 132. Connecting rod; 133. Sliding sleeve; 134. Sliding block; 135. Rocker arm; 136. Tenon. Detailed Implementation

[0037] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0038] Example 1

[0039] Please see Figure 10 This invention provides a technical solution: a heat-free compound fertilizer preparation process, comprising the following steps:

[0040] S1. Weigh nitrogen, phosphorus, and potassium raw materials (such as urea, ammonium phosphate, and potassium chloride) according to the formula, mix them with alkaline materials (such as magnesium oxide), and then grind the mixed materials in a Raymond mill to 200 mesh to obtain powder materials.

[0041] S2. The feeding auger 121 delivers the powder material into the drum 11. The drum 11 is driven to rotate by the motor. The pusher 111 in the drum 11 is brought to a high point and thrown, so that the powder material is dispersed and has a longer falling distance.

[0042] S3. Add sulfuric acid to drum 11. The liquid sulfuric acid is atomized and sprayed out through the nozzle. The atomized sulfuric acid gathers in the spraying area 123. The powdered material is sprinkled and dispersed from above the spraying area 123. The atomized sulfuric acid collides and mixes with the dry powder falling from above, making the dry powder wet. The sulfuric acid reacts with the alkaline material in the powder to generate moisture and heat. The moisture forms "liquid bridges" between the contact points of the powder particles, generating surface tension and initially "binding" the powder together to form agglomerates. During the rotation of drum 11, the agglomerates adhere to the powder to form particles. The heat generated by the neutralization reaction keeps the internal temperature of drum 11 between 35℃ and 50℃, drying the particles and preventing them from sticking together. The reaction between sulfuric acid and alkaline material also forms a protective film on the surface of the particles. When used for fertilization, the film opens below the surface to dilute nutrients into the soil, which not only improves the soil and reduces volatilization, but also increases the utilization of compound fertilizer, greatly reduces soil clumping, and prevents the soil from becoming pulverized.

[0043] S4. The granules are discharged from the discharge port 115, and after being screened, they are measured and packaged.

[0044] Example 2

[0045] Please see Figure 1-9 This invention provides a technical solution: a heat-free compound fertilizer preparation system, used to implement the heat-free compound fertilizer preparation process in Embodiment 1, comprising a frame 1, on which are arranged:

[0046] A roller 11 with its end closed and its discharge port 115 located on the side wall is rotatably mounted on the frame 1. A pusher 111 extending along a spiral is provided on the inner wall of the roller 11, and a storage trough 114 is provided on the top plate of the pusher 111.

[0047] The mounting cylinder 12 is fixedly mounted on the frame 1 and its end extends into the interior of the drum 11. The interior of the mounting cylinder 12 is equipped with a feeding auger 121 and an atomizing nozzle 122, wherein:

[0048] The pusher 111 rotates with the roller 11 to deliver material from above the spraying area 123 of the atomizing nozzle 122 through the storage trough 114.

[0049] Specifically, the roller 11 has a gear ring in the middle for easy motor drive, and the mounting cylinder 12 has a pipe for the flow of liquid sulfuric acid. The atomizing nozzle 122 is connected to the end of the pipe.

[0050] Furthermore, the atomizing nozzle 122 on the mounting cylinder 12 is tilted upwards. Sulfuric acid is supplied to the atomizing nozzle 122 through a pipe. The atomizing nozzle 122 atomizes the liquid sulfuric acid and sprays it upwards at an angle, forming a mist. Figure 3 In the spraying area 123 shown, the mist-like sulfuric acid material can be suspended in the spraying area 123 for a period of time so that it can come into contact with the powdery material sprayed down from above.

[0051] Furthermore, during operation, the feeding auger 121 delivers the powdered material into the drum 11. The rotating drum 11, via the pusher 111, moves the powdered material upwards and through the storage trough 114, delivers the dry powdered material to a higher position. Liquid sulfuric acid is atomized and sprayed out through nozzles, and the atomized sulfuric acid gathers in the spraying area 123. The powdered material falls and disperses from above the spraying area 123. The atomized sulfuric acid collides and mixes with the dry powder falling from above, making the dry powder wet. The sulfuric acid also undergoes a neutralization reaction with the alkaline materials in the powdered material, generating moisture and heat. The moisture forms "liquid bridges" between the contact points of the powder particles, generating surface tension and initially "binding" the powder together. Initially, agglomerates are formed. Then, as the roller 11 rotates, the agglomerates roll along the inner wall of the roller 11. The agglomerates adhere to more powder and gradually form small particles. The heat generated by the neutralization reaction raises the internal temperature of the roller 11, accelerating the evaporation of moisture in the particles and drying the particles to prevent them from sticking together. The roller 11 continues to rotate, and the storage trough 114 on the pusher 111 lifts the small particles and powder together and moves along the inclined storage trough 114. Since the particles have a greater ability to roll along the slope than the powder, most of the particles and a small part of the powder will move directly along the inclined pusher 111 towards the inner side of the roller 11. Most of the powder will gather and remain in the storage trough 114 and continue to move with the pusher 111 to the higher point, where it will come into contact with the mist-like sulfuric acid again.

[0052] In another embodiment of the present invention, the inside of the roller 11 is provided with a plurality of guides 112 arranged in sequence and in the same spiral direction as the pusher 111. The tail end of the innermost guide 112 is directly opposite the discharge port 115, and the slope of the top plate of the pusher 111 and the plurality of guides 112 decreases sequentially.

[0053] Specifically, during the rotation of the drum 11, because the particles have a greater rolling ability along the slope than the powder, most of the particles and a small portion of the powder will move directly along the inclined pusher 111 towards the inner side of the drum 11, and then fall to the top of the guide 112 with a smaller inner slope. Since the larger the diameter of the particles, the greater their rolling ability along the slope, the larger diameter particles in the material at the top of the guide 112 can still continue to move backward along the top of the guide 112, while the smaller diameter particles and powder will remain on the guide 112. The material at the top of the feeder 112 moves to a higher position along with the feeder 112. When the top plate of the feeder 112 tilts towards the middle of the drum 11, the material at the top of the feeder 112 is thrown off. The thrown-off material rolls along the inner wall of the drum 11. Smaller particles gradually stick to the powder and become larger during the rolling. Then they can move along the spirally extended top plate of the feeder 112 towards the inside of the drum. This process is repeated multiple times. Particles that meet the size requirements can move along the top plates of multiple feeders 112 towards the direction close to the discharge port 115 and then be discharged from the discharge port 115.

[0054] In another embodiment of the present invention, the interior of the mounting cylinder 12 is provided with a return feeder 113 that is distributed opposite to the feeder 112 and has the opposite spiral direction.

[0055] Specifically, the slope of the return feeder 113 is greater than the slope of the pusher 111.

[0056] Furthermore, as the drum 11 continues to rotate, particles and powder continuously move towards the inner side of the drum 11. The material inside the drum 11 section corresponding to the inner guide 112 is mostly granular, lacking powder that can combine with the particles. Particles that meet the size requirements can move along the top plate of the guide 112 towards the discharge port 115, while particles that do not meet the size requirements are thrown off by the guide 112 and come into contact with the return feeder 113 during the rotation of the drum 11. The spiral direction of the return feeder 113 is opposite to that of the guide 112. The return feeder 113 guides the particles that do not meet the size requirements inside the drum 11 to the outer side of the drum 11, where they combine with the powder located on the outer side of the drum 11 and grow larger, thus becoming particles that meet the size requirements.

[0057] In another embodiment of the present invention, the inside of the roller 11 is provided with a pair of baffle blocks 116 corresponding to the pusher 111 and the outermost guide 112 respectively. The cross-section of the baffle block 116 is a right triangle, the hypotenuse is parallel to the end of the roller 11, and the side edge faces the outside of the roller 11.

[0058] Specifically, during the rotation of the drum 11, the material moves along the inner wall of the drum 11 and gradually comes into contact with the pusher 111. The granular and powdery materials accumulate in the storage trough 114 on the pusher 111. Since the ability of granules to roll along the slope is greater than that of powder, most of the granules and a small part of the powder will move directly along the inclined pusher 111 towards the inner side of the drum 11. Most of the powder is gathered between the stop block and the pusher 111. Due to the bridging effect, it continues to move with the pusher 111 to a higher point and comes into contact with the misty sulfuric acid material again.

[0059] Furthermore, during the rotation of the drum 11, the material moves along the inner wall of the drum 11 and gradually comes into contact with the feeder 112. The granular and powdery materials are lifted by the top of the feeder 112. Since the granules have a greater ability to roll along the slope than the powder, the larger granules will move directly along the inclined feeder 112 towards the inner side of the drum 11. The smaller granules and powder will remain on the top of the feeder 112 and slide during the movement of the feeder 112, thus accumulating between the baffle and the feeder 112. Due to the bridging effect, they continue to move with the feeder 112. When the feeder 112 reaches a high point and the top plate tilts towards the middle of the drum 11, it separates from the feeder 112 and falls onto the inner wall of the drum 11. It then moves with the inner wall of the drum 11, and the granules and powder further adhere, increasing the diameter of the granules. Since there is less powder in the area of ​​the drum 11 corresponding to the feeder 112, the baffle 116 is not needed, and the granules are screened only by their own inclination.

[0060] In another embodiment of the present invention, both the pusher 111 and the guide 112 are provided with striking blocks 13 arranged in a spiral array. Multiple striking blocks 13 move with the rotation of the roller 11 and collide with the inner wall of the corresponding pusher 111 or guide 112 in sequence.

[0061] Specifically, the striking block 13 is provided with a connecting rod 132, and the pusher 111 and the guide 112 are both provided with mounting rods 131. The end of the mounting rod 131 is rotatably connected to the end of the connecting rod 132. The mounting rod 131 is offset from the axis of the roller 11. A sliding sleeve 133 is sleeved on the mounting rod 131. The pusher 111 and the guide 112 are both provided with an arc-shaped rod coaxial with the roller 11. An arc-shaped groove coaxial with the roller 11 is opened on the arc-shaped plate. A slider 134 is slidably arranged on the arc-shaped groove. A rocker arm 135 is provided between the slider 134 and the sliding sleeve 133.

[0062] Furthermore, during the movement of the pusher 111 or guide 112 from a high point to a low point, the sliding sleeve 133 spans the mounting rod 131 and the connecting rod 132, with the mounting rod 131 and the connecting rod 132 on the same straight line, and the slider 134 moves along the tenon 136 from left to right (within the middle). Figure 7As shown in the diagram (the upper end of the tenon 136 is to the right and the lower end is to the left), the slider 134 moves upwards towards the mounting rod 131 by pushing the sliding sleeve 133 against the rocker arm 135. When the slider 134 is directly opposite the mounting rod 131, the sliding sleeve 133 separates from the connecting rod 132, the connecting rod 132 is unlocked, and the striking block 13 falls under the action of gravity, colliding with the inner wall of the pusher 111 or the inner wall of the guide 112, shaking the material attached to the top plate of the pusher 111 or the top plate of the guide 112 off. The roller 11 continues to rotate, the slider 134 continues to move to the right, and pulls the sliding sleeve 133 through the rocker arm 135. The end of the sliding sleeve 133 pushes the connecting rod 132, so that the connecting rod 132 and the mounting rod 131 return to the same straight line.

[0063] Furthermore, as the pusher 111 or guide 112 moves from a low point to a high point, the slider 134 moves from right to left along the tenon 136. The slider 134 pushes the sliding sleeve 133 upwards towards the mounting rod 131 via the rocker arm 135. When the slider 134 is directly facing the mounting rod 131, the sliding sleeve 133 separates from the connecting rod 132, the connecting rod 132 unlocks, and the striking block 13 falls under the action of gravity, colliding with the inner wall of the pusher 111 or guide 112, causing the pusher 111 or guide 112 to vibrate, promoting the material on the pusher 111 or guide 112 to move towards the inside of the rotating drum.

[0064] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A process for preparing a heat-free compound fertilizer, characterized in that, Includes the following steps: S1. Weigh nitrogen, phosphorus, and potassium raw materials according to the formula, mix and grind them with alkaline materials to obtain powder materials; S2, The feeding auger (121) feeds the powder material into the drum (11), and is carried to a high point and scattered by the pusher (111) in the rotating drum (11); S3. Add sulfuric acid material to the drum (11). The powder is mixed with the sulfuric acid material. The sulfuric acid material and the alkaline powder react to generate water and heat. The powder is moistened by water and forms granules in the drum (11). The heat dries the excess water. S4. The particles are discharged from the outlet (115), and after being screened, they are measured and packaged.

2. A heat-free compound fertilizer preparation system, used to implement the heat-free compound fertilizer preparation process according to claim 1, characterized in that, Includes a frame (1), on which are provided: A roller (11) with its end closed and its outlet (115) located on the side wall is rotatably mounted on the frame (1). A pusher (111) extending along a spiral is provided on the inner wall of the roller (11), and a storage trough (114) is provided on the top plate of the pusher (111). The mounting cylinder (12) is fixedly mounted on the frame (1) and its end extends into the interior of the drum (11). The interior of the mounting cylinder (12) is provided with a feeding auger (121) and an atomizing nozzle (122), wherein: The pusher (111) rotates with the roller (11) to deliver material over the spraying area (123) of the atomizing nozzle (122) through the storage tank (114).

3. The heat-free compound fertilizer preparation system according to claim 2, characterized in that, The roller (11) is provided with a plurality of guides (112) arranged in sequence and in the same spiral direction as the pusher (111), with the tail end of the innermost guide (112) facing the discharge port (115).

4. The heat-free compound fertilizer preparation system according to claim 3, characterized in that, The slopes of the top plates of the pusher (111) and the plurality of guides (112) decrease sequentially.

5. The heat-free compound fertilizer preparation system according to claim 3, characterized in that, The mounting cylinder (12) is equipped with a return feeder (113) that is distributed opposite to the feeder (112) and has the opposite spiral direction.

6. The heat-free compound fertilizer preparation system according to claim 3, characterized in that, The inside of the roller (11) is provided a pair of stop blocks (116) that correspond to the pusher (111) and the outermost guide (112) respectively.

7. The heat-free compound fertilizer preparation system according to claim 6, characterized in that, The cross-section of the baffle block (116) is a right triangle, with the hypotenuse parallel to the end of the roller (11) and the side edge facing outwards from the roller (11).

8. The heat-free compound fertilizer preparation system according to claim 2, characterized in that, The atomizing nozzle (122) on the mounting cylinder (12) is tilted upwards.

9. The heat-free compound fertilizer preparation system according to claim 3, characterized in that, Both the pusher (111) and the guide (112) are provided with striking blocks (13) arranged along a spiral array inside.

10. The heat-free compound fertilizer preparation system according to claim 9, characterized in that, Multiple striking blocks (13) move as the roller (11) rotates and collide with the inner wall of the corresponding pusher (111) or guide (112) in sequence.

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