Preparation process of ammonium chloride rounded granular fertilizer

Abstract

The invention discloses a preparation process of an ammonium chloride rounded granular fertilizer, and relates to the technical field of granular fertilizer production. After ammonia chloride powder enters an extruding machine to be extruded, flour and pre-gelatinized tapioca flour are added into a mixture of obtained ammonium chloride particles and a small amount of ammonia chloride powder, then the mixed material is conveyed into a granulating barrel, urea sulfate and continuous water vapor are sprayed, and primary round ammonium chloride particles are obtained after granulation; and finally melting and drying at a high temperature of 380 DEG C to obtain the round ammonium chloride granular fertilizer. When the round ammonium chloride particles prepared by the method and other round particle fertilizers are used as a blended fertilizer, the uniform fertilizer application is realized, the later fertilizer removal is avoided, the production cost of a user is reduced, the preparation process is simple, the operation is easy, the cost is low, and the round effect of the ammonium chloride particles is obvious.

Description

Technical Field

[0001] The invention relates to the technical field of granular fertilizer production, in particular to a method for preparing rounded ammonium chloride granular fertilizer. Background Art

[0002] Blended fertilizer is a fertilizer containing any two or three of the three nutrients of nitrogen, phosphorus and potassium. It is made from unit fertilizer or compound fertilizer through simple mechanical mixing, and there is no significant chemical reaction during the mixing process. The main function of ammonium chloride fertilizer is to provide nitrogen to plants, promote plant growth, increase crop yield and quality, enhance stress resistance and improve soil properties.

[0003] Ammonium chloride fertilizer is used as a filler for blended fertilizers. It is mixed with other unit fertilizers or compound fertilizers in the form of extruded granules. At present, most unit fertilizers or compound fertilizers can be made into round granules by spraying urea sulfate after extrusion molding. However, the granules of ammonium chloride made by the current existing process are flat in appearance and have edges and burrs. When users use machines to spread fertilizers mixed with ammonium chloride granules, the flat ammonium chloride granules are not easy to go down, and the amount of fertilizer applied is reduced by as much as 20%, which seriously affects the crop's absorption of fertilizers. In order to prevent fertilizer loss in the later stage, it is necessary to increase the amount of fertilizer, which increases the user's production cost. Summary of the invention

[0004] In order to solve the above-mentioned technical problems, the present invention provides a preparation process of ammonium chloride rounded granular fertilizer. The prepared ammonium chloride rounded granules, when used as a mixed fertilizer with other round granular fertilizers, can achieve common and uniform fertilization, avoid fertilizer loss in the later stage, and reduce the production cost of users. The preparation process is simple, easy to operate, low in cost, and the ammonium chloride granules have a significant rounding effect.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: A preparation process of ammonium chloride round granular fertilizer is achieved by the following steps: 1) Raw material mixing: weigh 1 ton of ammonium chloride powder, 3 kg of flour, 1 kg of pre-gelatinized cassava flour, and 20 kg of urea sulfate viscous material; 2) Extrusion granulation: 1 ton of ammonium chloride powder in step 1) is conveyed into an extruder to obtain a mixture of 70% irregular ammonium chloride particles and 30% ammonium chloride powder. At this time, 3 kg of flour and 1 kg of pregelatinized cassava flour are added to the mixture, and the mixed materials are conveyed to a granulation cylinder. 20 kg of urea sulfate viscous material is sprayed on the mixed material in the granulation cylinder. As the granulation cylinder rotates, the unextruded ammonium chloride powder is adhered to the ammonium chloride particles by the viscosity of the urea sulfate viscous material, flour, and pregelatinized cassava flour, filling the holes on the surface of the extruded ammonium chloride particles. At the same time, water vapor is continuously sprayed to keep the surface of the ammonium chloride particles moist, and the burrs and edges on the surface of the extruded ammonium chloride particles are removed by mutual friction between the particles to form preliminarily rounded ammonium chloride particles. 3) Drying: The ammonium chloride particles formed in step 2) enter the drying drum, and the temperature of the drying drum is set to 380°C to melt the surface of the ammonium chloride particles. During the drying process, the ammonium chloride particles become round particles; 4) Cooling and forming: the rounded ammonium chloride particles obtained in step 3) are placed in a cooling device for cooling and forming; 5) Subsequent processing: the rounded ammonium chloride particles obtained in step 4) are screened, packaged, stored, and quality inspected. The spraying of the water vapor in step 2) is set to 1.5 tons / hour.

[0006] The urea sulfate viscous material in step 1) is formed by the reaction and dissolution of urea, water and concentrated sulfuric acid in a mass ratio of 3.6:1:1.

[0007] The ammonium chloride powder in step 1) can be replaced with ammonium sulfate crystal powder, and the drying drum temperature in step 3) is set to 235°C.

[0008] In the present invention, after the ammonium chloride powder enters the extruder for extrusion, flour and pre-gelatinized cassava flour are added to the obtained mixture of ammonium chloride particles and a small amount of ammonium chloride powder, and then the mixture is transported to a granulating cylinder for spraying with urea sulfate and continuous water vapor. The pre-gelatinized cassava flour and flour increase the viscosity of the ammonium chloride particles, and work together with urea sulfate to make the remaining ammonium chloride powder adhere to the ammonium chloride particles, fill the pits on the surface of the ammonium chloride particles after extrusion, and keep the surface of the ammonium chloride particles moist. In the process of rotating the granulating cylinder, the particles rub against each other so that the edges and burrs on the surface of the ammonium chloride particles are mutually smoothed and eliminated, forming initially rounded ammonium chloride particles, and finally enter a high-temperature drying process at 380°C. The drying cylinder makes the surface of the ammonium chloride particles in a molten state, and ammonium chloride particles with rounded surfaces are formed during the rolling process. Although the pre-gelatinized cassava powder and flour in this scheme are low-cost, they play a vital role in the process of making the flat ammonium chloride particles round. Combined with the continuous water vapor in the granulating cylinder and the specific temperature setting of the drying cylinder, the technical problem that the ammonium chloride extruded particles cannot be used to prepare round granular fertilizers is solved. The obtained ammonium chloride round granular fertilizer is more fully mixed with other round granular fertilizers, and the fertilizer is applied smoothly to avoid fertilizer loss in the later stage. In comparison, the amount of fertilizer applied is reduced, and the production cost is reduced without affecting the growth needs of crops. There is no precedent in the industry at present, and it is suitable for large-scale promotion and application. DETAILED DESCRIPTION

[0009] A preparation process of ammonium chloride round granular fertilizer is achieved by the following steps: 1) Raw material mixing: weigh 1 ton of ammonium chloride powder, 3 kg of flour, 1 kg of pre-gelatinized cassava flour, and 20 kg of urea sulfate viscous material; 2) Extrusion granulation: 1 ton of ammonium chloride powder in step 1) is conveyed into an extruder to obtain a mixture of 70% irregular ammonium chloride particles and 30% ammonium chloride powder. At this time, 3 kg of flour and 1 kg of pregelatinized cassava flour are added to the mixture, and the mixed materials are conveyed to a granulation cylinder. 20 kg of urea sulfate viscous material is sprayed on the mixed material in the granulation cylinder. As the granulation cylinder rotates, the unextruded ammonium chloride powder is adhered to the ammonium chloride particles by the viscosity of the urea sulfate viscous material, flour, and pregelatinized cassava flour, filling the holes on the surface of the extruded ammonium chloride particles. At the same time, water vapor is continuously sprayed to keep the surface of the ammonium chloride particles moist, and the burrs and edges on the surface of the extruded ammonium chloride particles are removed by mutual friction between the particles to form preliminarily rounded ammonium chloride particles. 3) Drying: The ammonium chloride particles formed in step 2) enter the drying drum, and the temperature of the drying drum is set to 380°C to melt the surface of the ammonium chloride particles. During the drying process, the ammonium chloride particles become round particles; 4) Cooling and forming: the rounded ammonium chloride particles obtained in step 3) are placed in a cooling device for cooling and forming; 5) Subsequent processing: the rounded ammonium chloride particles obtained in step 4) are screened, packaged, stored, and quality inspected. As a preferred embodiment, the spraying of the water vapor in step 2) is set to 1.5 tons / hour.

[0010] As a preferred embodiment, the urea sulfate viscous material in step 1) is formed by the reaction and dissolution of urea, water and concentrated sulfuric acid in a mass ratio of 3.6:1:1.

[0011] As an alternative, the ammonium chloride powder in step 1) can be replaced with ammonium sulfate crystal powder, and the drying drum temperature in step 3) is set to 235°C. The screening system ensures that the finished product particles are of uniform size, removes unqualified particles, and qualified particles can be packaged for easy storage and sale. Appropriate packaging materials and packaging specifications can be selected, and the ammonium chloride granular fertilizer can be packed into bags or barrels, and labeled and instructions can be added. At the same time, it should be stored in a dry, well-ventilated warehouse, away from fire and oxidants to ensure that its quality is not damaged. The prepared ammonium chloride granular fertilizer needs to be tested to ensure that it meets the relevant standards and usage requirements. Common quality monitoring items include nitrogen content, solubility, humidity, particle size, etc.

[0012] After many tests, the ammonium chloride particles obtained in this preparation scheme are round. The particles are extracted and their shapes are observed under an optical microscope. The particle outline is infinitely close to a circle. After measurement, the ratio of its major axis to its minor axis is 0.9-1.0, which proves that the roundness of the particles has reached or even exceeded that of the existing round granular compound fertilizers and can achieve the expected effect.

[0013] At the same time, a large number of particle photos or microscopic images on the production line were analyzed by image analysis method, and the roundness of the particles was evaluated by calculating the particle boundary curvature or the ratio of circumference to area. The production line was monitored online, and the parameters obtained were comparable to the roundness parameters of round granular fertilizers on the market, proving that this method can be implemented. Of course, the above description is not a limitation of the invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A preparation process for ammonium chloride round granular fertilizer, characterized in that: This is accomplished by the following steps: 1) Raw material mixing: weigh 1 ton of ammonium chloride powder, 3 kg of flour, 1 kg of pre-gelatinized cassava flour, and 20 kg of urea sulfate viscous material; 2) Extrusion granulation: 1 ton of ammonium chloride powder in step 1) is conveyed into an extruder to obtain a mixture of 70% irregular ammonium chloride particles and 30% ammonium chloride powder. At this time, 3 kg of flour and 1 kg of pregelatinized cassava flour are added to the mixture, and the mixed materials are conveyed to a granulation cylinder. 20 kg of urea sulfate viscous material is sprayed on the mixed material in the granulation cylinder. As the granulation cylinder rotates, the unextruded ammonium chloride powder is adhered to the ammonium chloride particles by the viscosity of the urea sulfate viscous material, flour, and pregelatinized cassava flour, filling the holes on the surface of the extruded ammonium chloride particles. At the same time, water vapor is continuously sprayed to keep the surface of the ammonium chloride particles moist, and the burrs and edges on the surface of the extruded ammonium chloride particles are removed by mutual friction between the particles to form preliminarily rounded ammonium chloride particles. 3) Drying: The ammonium chloride particles formed in step 2) enter the drying drum, and the temperature of the drying drum is set to 380°C to melt the surface of the ammonium chloride particles. During the drying process, the ammonium chloride particles become round particles; 4) Cooling and forming: the rounded ammonium chloride particles obtained in step 3) are placed in a cooling device for cooling and forming; 5) Subsequent processing: the rounded ammonium chloride particles obtained in step 4) are screened, packaged, stored, and quality inspected.

2. The preparation process of a kind of ammonium chloride round granular fertilizer according to claim 1, characterized in that, The spraying of the water vapor in step 2) is set to 1.5 tons / hour.

3. The preparation process of a kind of ammonium chloride round granular fertilizer according to claim 1, characterized in that, The urea sulfate viscous material in step 1) is formed by the reaction and dissolution of urea, water and concentrated sulfuric acid in a mass ratio of 3.6:1:

1.

4. The preparation process of a kind of ammonium chloride round granular fertilizer according to claim 1, characterized in that, The ammonium chloride powder in step 1) can be replaced with ammonium sulfate crystal powder, and the drying drum temperature in step 3) is set to 235°C.