Controlled loss compound fertilizer and preparation process and feeding flap structure of granulation mixing tank

Abstract

The control-loss compound fertilizer includes the following components: 10-80 parts of nitrogen fertilizer, 10-40 parts of phosphate fertilizer, 10-45 parts of potash fertilizer, 0.1-5 parts of control-loss agent, 0.5-10 parts of calcium powder, and 0.1-6 parts of functional additives. In the preparation process, the feeding flap structure of the granulation mixing tank includes a mixing tank body, a discharge pipe, a hinged arm, and a valve plate. A bolt rod is provided at the center of the front side of the valve plate. The first rod body and the second rod body of the bolt rod are respectively provided with a first external thread and a second external thread. The tooth top circle diameter of the first external thread is smaller than that of the second external thread, and the helix angle of the first external thread is smaller than that of the second external thread. The second rod body is provided with a valve body made of polytetrafluoroethylene, the valve body is truncated, and the valve body is screwed to the second rod body. The front side of the first rod body exceeds the front side of the valve body and is screwed with a locking nut matching the first external thread on the first rod body. The discharge pipe is provided with a conical surface that matches the circumference of the truncated valve body along its axial direction close to the valve plate. It has good sealing performance, is not easy to leak, the flap valve has stable performance and a long overall life.

Description

Technical Field

[0001] The invention relates to a controlled-loss compound fertilizer, a preparation process thereof and a feeding flap structure of a granulation mixing tank. Background Art

[0002] Controlled-release compound fertilizers are key products for improving soil fertility and promoting plant growth. During the production process, the particles need to be coated, and the coating material is not easily degraded. Controlled-release compound fertilizers add loss-control agents with nutrient capture effects to the formula, which solves the inefficiency of fertilizer nutrient loss and volatilization, improves fertilizer utilization, and reduces environmental pollution. High-tower granulation technology is often used in the production process, which effectively improves the particle uniformity and yield rate of controlled-release fertilizers.

[0003] In the production process of controlled-loss compound fertilizer, flap valve is a commonly used discharge device, and its structure and function are widely used in many industries, such as the relevant structural design mentioned in Chinese patent CN217583202U. However, in the high-tower granulation mixing tank of controlled-loss compound fertilizer, the use of traditional stainless steel flap valve as the discharge port has some significant shortcomings. The design of the conventional flap valve forms a hard seal between it and the discharge pipe. Due to the high viscosity of the control loss agent, the valve is not closed tightly, resulting in leakage problems, especially for the second mixing tank (generally, the first mixing tank is injected with room temperature raw materials, and the second mixing tank is injected with processed high-temperature materials). Due to the high feed temperature, the operator is easily scalded by the high-temperature material leaking from the valve plate when repairing the emulsifier. Summary of the invention

[0004] The first technical problem to be solved by the present invention is to provide a controlled-loss compound fertilizer, which has a good controlled-loss effect, meets the requirements of crops and the environment, and has a high nutrient utilization rate.

[0005] The second technical problem to be solved by the present invention is to provide a preparation process of the above-mentioned controlled-loss compound fertilizer, which has simple steps, convenient processing and is suitable for batch production.

[0006] The third technical problem to be solved by the present invention is to provide a feeding flap structure of the granulation mixing tank in the preparation process of the above-mentioned controlled loss compound fertilizer, wherein the flap has good sealing performance, is not easy to leak, and the flap valve has stable performance and a long overall life.

[0007] To solve the first technical problem mentioned above, the present invention provides a loss-controlling compound fertilizer, comprising the following components in parts by weight: 10 to 80 parts of nitrogen fertilizer, 10 to 40 parts of phosphate fertilizer, 10 to 45 parts of potassium fertilizer, 0.1 to 5 parts of loss-control agent, 0.5 to 10 parts of calcium powder, and 0.1 to 6 parts of functional additives.

[0008] Preferably, the nitrogen fertilizer is a combination of urea and dry ammonium or wet ammonium; the phosphate fertilizer is a combination of one or more of monoammonium phosphate, diammonium phosphate, and double superphosphate; the potash fertilizer is a combination of one or more of potassium sulfate, potassium chloride, and potassium nitrate; the loss control agent is a combination of one or more of resin-coated loss control agents, fatty acid salt loss control agents, or biopolymer materials;

[0009] Among them, the functional additives are composed of one or more combinations of trace elements, auxiliary agents, and synergists; among them, 0.1 to 2 parts of trace elements are selected from one or a mixture of zinc, boron, iron, and copper; 0.5 to 3 parts of auxiliary agents are selected from one or a mixture of two anti-caking agents and moisture-proof agents; 0.1 to 1 part of synergists are selected from one or a mixture of two of humic acid and alginic acid.

[0010] In order to solve the above second technical problem, the present invention provides a preparation process of a controlled loss compound fertilizer, comprising the following steps:

[0011] Step 1: transporting urea to a melting tank in proportion and heating and melting it into a molten liquid;

[0012] Step 2: nitrogen fertilizer, phosphate fertilizer, potash fertilizer, calcium powder and loss control agent are conveyed in proportion to form a mixed slurry through different metering belt scales; the mixed slurry is conveyed from the first-stage mixing tank to the second-stage mixing tank through a mixing pipe device; then, the mixed slurry is granulated by a nozzle, cooled and falls into a collecting hopper to obtain coarse particles;

[0013] Step 3: transport the coarse particles in step 2 into the coating kiln, add functional additives for coating, and obtain the controlled loss compound fertilizer after packaging.

[0014] In order to solve the third technical problem mentioned above, the present invention provides a feeding flap structure of a granulating mixing trough in the processing technology of controlled loss compound fertilizer, comprising a mixing trough body, a discharge pipe, an articulated arm, and a valve plate. The discharge pipe is arranged on the circumferential side wall of the mixing trough body, and the end of the discharge pipe exceeds the circumferential side wall of the mixing trough body. The valve plate is installed on the inner wall of the mixing trough through the articulated arm and cooperates with the discharge pipe. It is characterized in that: the side of the valve plate close to the discharge pipe along its normal direction is the front side, and the side away from the discharge pipe is the rear side. A bolt rod extending forward along the normal direction is provided at the center of the front side of the valve plate. The bolt rod comprises a first rod body and a second rod body which are coaxially arranged and connected front and back. The first rod body is circumferentially provided with a first external thread, and the second rod body is circumferentially provided with a second external thread. The tooth top circle diameter of the first external thread is smaller than The diameter of the tooth bottom circle of the second external thread, the helix angle of the first external thread is smaller than the helix angle of the second external thread, and a valve body made of polytetrafluoroethylene is provided on the second rod body. The valve body is truncated cone-shaped, and its axial direction is forward and backward. The front diameter of the truncated cone-shaped valve body is small, and the rear diameter is large. A threaded hole is provided at the axis core of the truncated cone-shaped valve body that penetrates it axially. The internal thread of the threaded hole matches the second external thread. The valve body is screwed to the second rod body, and the rear side of the valve body is against the front side of the valve plate. The front side of the valve body exceeds the front side of the second rod body, and the front side of the first rod body exceeds the front side of the valve body and is screwed with a locking nut matching the first external thread on the first rod body. The rear side of the locking nut is tightly attached to the front side of the valve body, and a conical surface that matches the circumference of the truncated cone-shaped valve body is provided on one end of the discharge pipe along its axial direction close to the valve plate.

[0015] Advantages of the present invention:

[0016] 1. The controlled loss compound fertilizer provided by the present invention has good control effect, meets the requirements of crops and the environment, and has high nutrient utilization rate;

[0017] 2. The preparation method of the controlled-loss compound fertilizer has simple steps, convenient processing and is suitable for mass production.

[0018] 3. The valve body of the present invention adopts a truncated cone valve body of polytetrafluoroethylene, which has a conical surface. The discharge pipe is also provided with a corresponding conical surface. Compared with the traditional straight surface sealing, the conical surface sealing effect has a larger fitting area and a better sealing effect. Polytetrafluoroethylene has excellent chemical stability, corrosion resistance, sealing, high lubricity and non-stickiness, electrical insulation and good anti-aging resistance. The installation method of the valve body adopts a two-stage bolt rod. If the screw connection between the valve body and the second rod body is loose, the valve body has a tendency to drive the locking nut to rotate. However, since the helix angle of the first external thread is smaller than the helix angle of the second external thread (the locking nut is driven by the valve body through friction, so the rotation angle of the locking nut is less than or equal to the rotation angle of the valve body), the axial movement distance of the valve body is greater than the axial movement distance of the locking nut, which will only make the locking nut fit more closely with the valve body, and will not drive the locking nut to rotate. This structure makes the valve body itself have extremely high mechanical stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the present invention (flap closed state).

[0020] Figure 2 It is another structural schematic diagram of the present invention (flap open state). DETAILED DESCRIPTION

[0021] Example 1

[0022] A loss control compound fertilizer comprises the following components in parts by weight: 30 parts of urea, 20 parts of dry ammonium, 20 parts of ammonium phosphate, 20 parts of potassium chloride, 0.5 parts of a loss control agent, 5 parts of calcium powder, and 4.5 parts of a functional additive;

[0023] Preferably, the processing technology of the controlled loss compound fertilizer comprises the following steps:

[0024] Step 1: transporting urea to a melting tank in proportion and heating and melting it into a molten liquid;

[0025] Step 2: nitrogen fertilizer, phosphate fertilizer, potash fertilizer, calcium powder, loss control agent and other molten liquids in the first step are transported into mixed slurry in proportion through different metering belt scales. The mixed slurry is transported from the first-stage mixing tank to the second-stage mixing tank through a mixing pipe device, and then granulated by a nozzle, cooled and then falls into a collecting hopper to obtain coarse particles.

[0026] Step 3: transport the coarse particles in step 2 into the coating kiln, add functional additives for coating, and obtain the controlled loss compound fertilizer after packaging.

[0027] See also Figure 1-Figure 2A mixing trough feeding flap structure of a high-tower granulation process for controlling loss of compound fertilizers, comprising a mixing trough body 1, a discharge pipe 2, an articulated arm 3, and a valve plate 4, wherein the discharge pipe 2 is arranged on the circumferential side wall of the mixing trough body 1, and the end of the discharge pipe 2 exceeds the circumferential side wall of the mixing trough body 1, and the valve plate 4 is installed on the inner wall of the mixing trough through the articulated arm 3 and cooperates with the discharge pipe 2, and the side of the valve plate 4 along its normal direction close to the discharge pipe 2 is the front side, and the side away from the discharge pipe 2 is the rear side, and a bolt rod 5 extending forward along the normal direction is provided at the center of the front side of the valve plate 4, and the bolt rod 5 comprises a first rod body 51 and a second rod body 52 which are coaxially arranged and connected front and back, the first rod body 51 is circumferentially provided with a first external thread, and the second rod body 52 is circumferentially provided with a second external thread, and the tooth top circle diameter of the first external thread is smaller than the tooth bottom circle diameter of the second external thread The helix angle of the first external thread is smaller than the helix angle of the second external thread. A valve body 6 made of polytetrafluoroethylene is provided on the second rod body 52. ​​The valve body 6 is truncated cone-shaped, and its axial direction is forward and backward. The front diameter of the truncated cone-shaped valve body 6 is small and the rear diameter is large. A threaded hole is provided at the axis core of the truncated cone-shaped valve body 6 to penetrate it axially. The internal thread of the threaded hole matches the second external thread. The valve body 6 is screwed to the second rod body 52. ​​The rear side of the valve body 6 is against the front side of the valve plate 4. The front side of the valve body 6 exceeds the front side of the second rod body 52. ​​The front side of the first rod body 51 exceeds the front side of the valve body 6 and is screwed with a locking nut 7 matching the first external thread on the first rod body 51. The rear side of the locking nut 7 is tightly attached to the front side of the valve body 6. A conical surface 21 that matches the circumferential direction of the truncated cone-shaped valve body 6 is provided on one end of the discharge pipe 2 along its axial direction close to the valve plate 4.

[0028] Advantages of the present invention:

[0029] 1. The controlled loss compound fertilizer provided by the present invention has good control effect, meets the requirements of crops and the environment, and has high nutrient utilization rate;

[0030] 2. The preparation method of the controlled-loss compound fertilizer has simple steps, convenient processing and is suitable for mass production.

[0031] 3. The valve body 6 of the present invention adopts a truncated cone-shaped valve body 6 of polytetrafluoroethylene. The truncated cone-shaped valve body 6 has a conical surface, and a corresponding conical surface 21 is also provided on the discharge pipe 2. The sealing effect of the conical surface 21 is compared with the traditional straight surface sealing, the fitting area becomes larger, and the sealing effect is good. Polytetrafluoroethylene has excellent chemical stability, corrosion resistance, sealing, high lubricity and non-stickiness, electrical insulation and good anti-aging resistance. The valve body 6 is installed by using a two-stage bolt rod 5. If the screw connection between the valve body 6 and the second rod body 52 becomes loose, the valve body 6 tends to drive the locking nut 7 to rotate. However, since the helix angle of the first external thread is smaller than the helix angle of the second external thread (the locking nut 7 is driven by the valve body 6 through friction, so the rotation angle of the locking nut 7 is less than or equal to the rotation angle of the valve body 6), the axial movement distance of the valve body 6 is greater than the axial movement distance of the locking nut 7. This will only make the locking nut 7 fit more closely to the valve body 6 and will not drive the locking nut 7 to rotate. This structure makes the valve body 6 itself have extremely high mechanical stability.

Claims

1. A controlled loss compound fertilizer, characterized in that: The invention comprises the following components in parts by weight: 10 to 80 parts of nitrogen fertilizer, 10 to 40 parts of phosphate fertilizer, 10 to 45 parts of potash fertilizer, 0.1 to 5 parts of loss control agent, 0.5 to 10 parts of calcium powder and 0.1 to 6 parts of functional additive.

2. The controlled loss compound fertilizer according to claim 1, characterized in that: The nitrogen fertilizer is a combination of urea and dry ammonium or wet ammonium; the phosphate fertilizer is a combination of one or more of monoammonium phosphate, diammonium phosphate, and double superphosphate; the potash fertilizer is a combination of one or more of potassium sulfate, potassium chloride, and potassium nitrate; the loss control agent is a combination of one or more of resin-coated loss control agents, fatty acid salt loss control agents, or biopolymer materials; Among them, the functional additives are composed of one or more combinations of trace elements, auxiliary agents, and synergists; among them, 0.1 to 2 parts of trace elements are selected from one or a mixture of zinc, boron, iron, and copper; 0.5 to 3 parts of auxiliary agents are selected from one or a mixture of two anti-caking agents and moisture-proof agents; 0.1 to 1 part of synergists are selected from one or a mixture of two of humic acid and alginic acid.

3. The preparation process of the controlled loss compound fertilizer according to claim 1 or 2, characterized in that: The following steps are involved: Step 1: transporting urea to a melting tank in proportion and heating and melting it into a molten liquid; Step 2: nitrogen fertilizer, phosphate fertilizer, potash fertilizer, calcium powder and loss control agent are conveyed in proportion to form a mixed slurry through different metering belt scales; the mixed slurry is conveyed from the first-stage mixing tank to the second-stage mixing tank through a mixing pipe device; then, the mixed slurry is granulated by a nozzle, cooled and falls into a collecting hopper to obtain coarse particles; Step 3: transport the coarse particles in step 2 into the coating kiln, add functional additives for coating, and obtain the controlled loss compound fertilizer after packaging.

4. The feeding flap structure of the granulation mixing tank in the processing technology of the controlled loss compound fertilizer according to claim 3 is characterized by: The invention comprises a mixing trough body, a discharge pipe, an articulated arm and a valve plate. The discharge pipe is arranged on the circumferential side wall of the mixing trough body. The end of the discharge pipe exceeds the circumferential side wall of the mixing trough body. The valve plate is installed on the inner wall of the mixing trough through the articulated arm and cooperates with the discharge pipe. The invention is characterized in that the side of the valve plate close to the discharge pipe along its normal direction is the front side, and the side away from the discharge pipe is the rear side. A bolt rod extending forward along the normal direction is provided at the center of the front side of the valve plate. The bolt rod comprises a first rod body and a second rod body which are coaxially arranged and connected front and back. The first rod body is circumferentially provided with a first external thread, and the second rod body is circumferentially provided with a second external thread. The top circle diameter of the first external thread is smaller than the bottom circle diameter of the second external thread. The spiral rise of the first external thread is The angle is smaller than the helix angle of the second external thread, and the second rod body is provided with a valve body made of polytetrafluoroethylene. The valve body is truncated cone-shaped, and its axial direction is forward and backward. The front diameter of the truncated cone-shaped valve body is small, and the rear diameter is large. A threaded hole is provided at the axis core of the truncated cone-shaped valve body which penetrates it axially, and the internal thread of the threaded hole matches the second external thread. The valve body is screwed to the second rod body, and the rear side of the valve body is against the front side of the valve plate. The front side of the valve body exceeds the front side of the second rod body, and the front side of the first rod body exceeds the front side of the valve body and is screwed with a locking nut matching the first external thread on the first rod body. The rear side of the locking nut is tightly attached to the front side of the valve body, and a conical surface which matches the circumference of the truncated cone-shaped valve body is provided on one end of the discharge pipe along its axial direction close to the valve plate.

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