Fluidized bed granulation system that can improve granulation efficiency

Abstract

This utility model relates to the field of fertilizer processing technology, and more particularly to a fluidized bed granulation system that can improve granulation efficiency. The fluidized bed granulation system includes a fluidized bed granulation device, within which a granulation section and a cooling section are formed. The granulation section is equipped with at least one sorting extractor, which is used to sort large-particle fertilizer within the granulation section and output it from the fluidized bed granulation device. Small-particle fertilizer seed crystals are added to the granulation section, and then molten fertilizer is sprayed into the granulation section, converting the small-particle fertilizer seed crystals into large-particle fertilizer, which then flows into the cooling section of the fluidized bed granulation device. During this process, the sorting extractor separates qualified particles, increasing the amount of molten fertilizer sprayed onto the small-particle fertilizer per unit area, improving the efficiency of converting small-particle fertilizer into large-particle fertilizer, and ultimately outputting more large-particle fertilizer, thus improving the efficiency of fluidized bed granulation for producing large particles.

Description

Technical Field

[0001] This utility model relates to the field of fertilizer processing technology, and in particular to a fluidized bed granulation system that can improve granulation efficiency. Background Technology

[0002] Fertilizer, as one of the essential factors for plant growth, plays a variety of roles and functions in agricultural production. The main form of fertilizer in agricultural production is granular fertilizer, which is divided into small granules (particle size less than 2mm) and large granules (particle size between 2 and 4mm). Because small granular fertilizer can cause "seedling burn" when it sticks to plant leaves, there is a higher demand for large granular fertilizer under the market mechanism. In the processing of granular fertilizer, the granulation of large granular fertilizer is commonly carried out through fluidized bed.

[0003] Fluidized bed granulation involves feeding materials into a closed container at once, where the materials are uniformly mixed and flowed to form granules.

[0004] In the traditional fluidized bed granulation process, when the material forms granules flowing in the fluidized bed, there are both large and small particles. The small particles need to be further sprayed and granulated to form larger particles, while the standard-compliant large particles will still be mixed in with the small particles until they are output from the outlet. During this process, the large particles that have already met the standard will not only continue to grow, wasting material, but will also affect the growth of small particles by occupying space, thus affecting the particle size compliance rate of the final output granular fertilizer and reducing the granulation efficiency of the fluidized bed. Utility Model Content

[0005] This invention provides a fluidized bed granulation system that can improve granulation efficiency, thereby solving the defect in the prior art where large-particle fertilizers that meet standards in the early stages of fluidized bed granulation can affect the efficiency of fluidized bed granulation.

[0006] This utility model provides a fluidized bed granulation system that can improve granulation efficiency, including a fluidized bed granulation device. The fluidized bed granulation device includes a fluidized bed granulator and a fluidized bed cooler. The fluidized bed granulator and the fluidized bed cooler respectively form a granulation section and a cooling section within the fluidized bed granulation device. The granulation section is used to convert small granular fertilizer seeds into large granular fertilizer. The cooling section is connected to the granulation section to receive and cool the granular fertilizer converted by the granulation section. The granulation section is provided with at least one sorting extractor, which is used to sort the large granular fertilizer in the granulation section and output it from the fluidized bed granulation device.

[0007] According to the present invention, a fluidized bed granulation system that can improve granulation efficiency is provided, wherein a seed inlet is provided in the granulation section away from the cooling section for adding small granular fertilizer seed crystals to the granulation section; the granulation section is provided with a plurality of sorting extractors, which are evenly spaced between the seed inlet and the cooling section.

[0008] According to the present invention, a fluidized bed granulation system that can improve granulation efficiency is provided. The granulation section is equipped with a granulation nozzle. The granulation nozzle is connected to a fertilizer melt source through a pipeline. The fertilizer melt source sprays fertilizer melt into the granulation section through the granulation nozzle to transform small fertilizer seed crystals in the granulation section into large fertilizer particles.

[0009] According to the present invention, a fluidized bed granulation system that can improve granulation efficiency is provided, wherein the fertilizer melt source is a liquid tank containing fertilizer melt, the liquid tank is connected to a delivery pump through a pipeline, and the delivery pump is connected to the granulation section through a pipeline.

[0010] The fertilizer melt in the liquid tank is at least one of urea melt, ammonium nitrate melt, calcium ammonium nitrate melt, and compound fertilizer melt, and the weight percentage of the fertilizer melt ranges from 92% to 99.7 wt%.

[0011] According to the present invention, a fluidized bed granulation system that can improve granulation efficiency is provided, wherein the outlet of the cooling section and the outlet of the sorting extractor are both connected to a material distribution screen through pipelines. The material distribution screen includes a small particle outlet and a large particle outlet. The small particle outlet is connected to the granulation section through a pipeline, and the large particle outlet outputs granular fertilizer products.

[0012] According to the present invention, a fluidized bed granulation system that can improve granulation efficiency is provided, wherein an intermediate cooler is provided on the pipeline connecting the outlet of the cooling section and / or the outlet of the sorting extractor to the material distribution screen.

[0013] According to the present invention, a fluidized bed granulation system that can improve granulation efficiency is provided, wherein a bucket elevator is installed on the pipeline connecting the small particle discharge port of the material distribution screen and the granulation section.

[0014] The large particle outlet is connected to a product cooler so that granular fertilizer products can be output through the product cooler outlet.

[0015] According to the present invention, a fluidized bed granulation system that can improve granulation efficiency is provided. The fluidized bed granulation system that can improve granulation efficiency further includes an atomizing fan. The atomizing fan is connected to an atomizing air preheater through a pipeline. The atomizing air preheater is connected to the fluidized bed granulation equipment through a pipeline.

[0016] The fluidized bed granulation system that can improve granulation efficiency also includes a fluidizing blower, which is connected to a fluidizing air preheater via a pipeline, and the fluidizing air preheater is connected to the fluidized bed granulation equipment via a pipeline.

[0017] The exhaust gas outlet of the fluidized bed granulation equipment is connected to a dust collector, and the dust collector is connected to an induced draft fan, so that the exhaust gas of the fluidized bed granulation equipment is discharged externally through the dust collector and the induced draft fan.

[0018] The fluidized bed granulation system provided by this utility model can improve granulation efficiency. Small granular fertilizer seed crystals are added into the granulation section of the fluidized bed granulation equipment, and then molten fertilizer liquid is sprayed into the granulation section to transform the small granular fertilizer seed crystals into large granular fertilizer, which then flows into the cooling section of the fluidized bed granulation equipment. During the conversion of small-particle fertilizer seeds into large-particle fertilizer, the conversion rates of each small-particle fertilizer seed are not the same. The sorting extractor separates the particles that are successfully converted earlier and transports them out, preventing them from participating in the later particle flow process. Only the small-particle fertilizer that does not meet the standards is retained in the granulation section and further sprayed and granulated into large particles. In this way, in the later granulation section, since there is no large-particle fertilizer involved in the flow, the amount of fertilizer melt sprayed onto the small-particle fertilizer per unit area increases, improving the efficiency of small-particle fertilizer to large-particle fertilizer conversion. This results in more large-particle fertilizer being output in the end. The large-particle fertilizer separated by the sorting extractor and the granular fertilizer output from the cooling section are output together, increasing the proportion of large-particle fertilizer output from the fluidized bed and improving the efficiency of fluidized bed large-particle production. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the flow of a fluidized bed granulation system that can improve granulation efficiency, provided by this utility model.

[0021] Reference numerals in the attached drawings: 1. Fluidized bed granulation equipment; 101. Granulation section; 102. Cooling section; 2. Separator and extractor; 3. Conveyor pump; 4. Material distribution screen; 5. Intercooler; 6. Bucket elevator; 7. Product cooler; 8. Atomizing fan; 9. Atomizing air preheater; 10. Fluidizing fan; 11. Fluidizing air preheater; 12. Dust collector; 13. Exhaust fan. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0023] In the description of the embodiments of this utility model, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this utility model. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] In the description of the embodiments of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this utility model based on the specific circumstances.

[0025] In this embodiment of the utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0026] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0027] The following is combined with Figure 1 This invention describes the specific composition of a fluidized bed granulation system that can improve granulation efficiency, and the specific process of a fluidized bed granulation method that can improve granulation efficiency.

[0028] One embodiment of this utility model provides a fluidized bed granulation system that can improve granulation efficiency. See [link to relevant documentation]. Figure 1 As shown, the fluidized bed granulation system that can improve granulation efficiency includes a fluidized bed granulation device 1. The fluidized bed granulation device 1 includes a fluidized bed granulator and a fluidized bed cooler. The fluidized bed granulator and the fluidized bed cooler respectively form a granulation section 101 and a cooling section 102 within the fluidized bed granulation device 1. The granulation section 101 is used to convert small granular fertilizer seeds into large granular fertilizer. The cooling section 102 is connected to the granulation section 101 to receive and cool the granular fertilizer converted by the granulation section 101. The granulation section 101 is provided with at least one sorting extractor 2, which is used to sort the large granular fertilizer within the granulation section 101 and output it from the fluidized bed granulation device 1.

[0029] It is understood that this fluidized bed granulation system, which can improve granulation efficiency, involves adding small-particle fertilizer seed crystals into the granulation section 101 of the fluidized bed granulation equipment 1, and then spraying molten fertilizer liquid into the granulation section 101 to transform the small-particle fertilizer seed crystals into large-particle fertilizer, which then flows into the cooling section 102 of the fluidized bed granulation equipment 1. During the process of converting small granular fertilizer seeds into large granular fertilizer, the conversion rates of the various small granular fertilizer seeds are not the same. The sorting extractor 2 separates the granules that are successfully converted earlier and transports them out, so that they do not participate in the later granule flow process. Only the small granular fertilizer that does not meet the standard is retained in the granulation section 101 and further sprayed and granulated into large granules. In this way, in the later granulation section, since there is no large granular fertilizer involved in the flow, the amount of fertilizer melt sprayed onto the small granular fertilizer per unit area increases, which improves the efficiency of converting small granular fertilizer into large granular fertilizer. This allows more large granular fertilizer to be output in the end. The large granular fertilizer separated by the sorting extractor 2 and the granular fertilizer output from the cooling section 102 are output together, which increases the proportion of large granular fertilizer output from the fluidized bed and improves the efficiency of fluidized bed large granule production.

[0030] In some embodiments of the fluidized bed granulation system of this utility model that can improve granulation efficiency, a seed inlet is provided in the granulation section 101 at a position away from the cooling section 102 for feeding small granular fertilizer seed crystals into the granulation section 101; the granulation section 101 is provided with a plurality of sorting extractors 2, which are evenly spaced between the seed inlet and the cooling section 102.

[0031] It is understood that the small-particle fertilizer seed crystals fed into the granulation section 101 from the seed crystal inlet can be small-particle fertilizers screened by the fluidized bed granulation system of this embodiment, small particles crushed by a traditional fluidized bed crusher, or small-particle seed crystals produced by specialized seed crystal production equipment. Multiple sorting extractors 2 are evenly spaced in the granulation section 101 to periodically separate qualified granular fertilizer particles as they flow from the seed crystal inlet to the cooling section 102. This ensures sufficient flow space for unqualified small-particle fertilizer particles, increases the probability of small-particle fertilizer particles being sprayed by the molten fertilizer, and improves the conversion rate into larger granular fertilizer particles. It should be understood that the sorting extractor 2 is a particle sorting device; it can be air classifier, adjusted on a perforated plate, or an existing sorting device to separate granular fertilizer particles that meet the particle size requirements.

[0032] In some specific examples of the fluidized bed granulation system of this utility model that can improve granulation efficiency, the granulation section 101 is equipped with a granulation nozzle. The granulation nozzle is connected to a fertilizer melt source via a pipeline. The fertilizer melt source sprays fertilizer melt into the granulation section 101 through the granulation nozzle to transform small fertilizer seed crystals in the granulation section 101 into large fertilizer particles. The fertilizer melt source is a liquid tank containing fertilizer melt, which is connected to a transfer pump 3 via a pipeline. The transfer pump 3 is connected to the granulation section 101 via a pipeline. The fertilizer melt in the liquid tank is at least one of urea melt, ammonium nitrate melt, calcium ammonium nitrate melt, and compound fertilizer melt, and the weight percentage of the fertilizer melt ranges from 92% to 99.7 wt%.

[0033] Understandably, in order to improve granulation efficiency, granulation nozzles are installed in the granulation section 101. The granulation nozzles are connected to the fertilizer melt source through pipelines, so that the fertilizer melt can be accurately sprayed onto the small fertilizer seed crystals inside the granulation section 101 through the granulation nozzles. In this process, the delivery pump 3 plays a key role. It draws and pressurizes the fertilizer melt contained in the liquid tank through pipelines and then delivers it to the granulation nozzles. In this way, the granulation nozzles can effectively spray the fertilizer melt onto the small fertilizer seed crystals inside the granulation section 101, thereby promoting the gradual growth of these small particles into large fertilizer particles.

[0034] In the fluidized bed granulation system of this invention, the fertilizer melt source can specifically be one or more liquid tanks containing fertilizer melt. These liquid tanks are connected to the delivery pump 3 through pipelines, and the delivery pump 3 is then connected to the granulation nozzle in the granulation section 101 through another set of pipelines. This ensures that the melt can be stably and continuously sprayed onto the small fertilizer seed crystals inside the granulation section 101 to support an efficient granulation process.

[0035] The weight percentage (wt%) of the fertilizer melt in the liquid tank is controlled between 92% and 99.7 wt%. This high concentration range helps ensure that the melt has appropriate physical properties (such as viscosity and flowability), which is conducive to the formation of high-quality granular fertilizer and can reduce moisture content and drying energy consumption. The fertilizer melt can be urea melt, ammonium nitrate melt, calcium ammonium nitrate melt, or compound fertilizer melt prepared according to requirements. Depending on the type of fertilizer melt selected, fertilizer products such as large-particle urea, large-particle ammonium nitrate, large-particle calcium ammonium nitrate, and large-particle compound fertilizer can be produced.

[0036] In some embodiments of the fluidized bed granulation system of this utility model that can improve granulation efficiency, see also... Figure 1As shown, the outlet of the cooling section 102 and the outlet of the sorting extractor 2 are both connected to the sorting screen 4 through pipelines. The sorting screen 4 includes a small particle outlet and a large particle outlet. The small particle outlet is connected to the granulation section 101 through pipelines, and the large particle outlet outputs granular fertilizer products.

[0037] To ensure that the final product particle size meets the standard and to effectively recover substandard particles to optimize resource utilization, the fluidized bed granulation system of this embodiment introduces a material separating screen 4. The outlet of the cooling section 102 and the outlet of the sorting extractor 2 are both connected to the material separating screen 4 via pipelines. The granular fertilizer output from the outlet of the cooling section 102 and the outlet of the sorting extractor 2 is screened by the material separating screen 4. The material separating screen 4 can distinguish between small granular fertilizer particles that fail to meet the predetermined size and large granular fertilizer particles that meet the requirements.

[0038] The small granular fertilizer particles screened out by the separating screen 4 are transported back to the granulation section 101 via a specific pipeline as seed crystals. These small granular fertilizer particles can further grow into qualified large granular fertilizer particles within the granulation section 101, thereby avoiding material waste and improving overall production efficiency. The large granular fertilizer particles that meet the preset specifications and are screened out by the separating screen 4 are directly output as finished products through the large particle outlet, ready for market entry or the next stage of processing.

[0039] This embodiment, through the effective screening of the separating screen 4, ensures that all granular fertilizers output as the final product meet specific size requirements, which helps improve product quality consistency. Reintroducing small granular fertilizers that do not meet size requirements into the granulation process not only reduces waste generation but also maximizes resource utilization and lowers production costs. It is understood that, based on changes in actual production and market demand, the proportion of granular fertilizers of different sizes can be flexibly controlled by adjusting the operating parameters of the separating screen 4, thereby adjusting production capacity.

[0040] Furthermore, in addition to the small particle discharge port and the large particle discharge port of the material sorting screen, an ultra-large particle discharge port can also be set. For example, ultra-large particles with a particle size greater than 4mm can be screened out through the ultra-large particle discharge port. The screened ultra-large particle fertilizer can be crushed by the crusher and then used as small particle seed crystals to supplement the granulation section 101, or it can be dissolved by the dissolving equipment and used as fertilizer melt to enter the fertilizer melt source.

[0041] In some specific aspects of the fluidized bed granulation system of this invention, which improves granulation efficiency, an intercooler 5 is installed on the pipeline connecting the outlet of the cooling section 102 and / or the outlet of the sorting extractor 2 to the distribution screen 4. The main function of the intercooler 5 is to provide additional cooling treatment to the material exiting the cooling section 102 and the sorting extractor 2. This ensures that large granular fertilizer particles are sufficiently cooled before entering the distribution screen 4, avoiding product quality problems or blockages during the sorting process due to excessive temperature. The cooling treatment by the intercooler 5 makes the differences between particles of different sizes more apparent, thereby improving the sorting accuracy of the distribution screen 4 in separating qualified products from small particles that need to be returned for further granulation. Simultaneously, lowering the material temperature reduces potential damage to the distribution screen 4 and its downstream equipment caused by high temperatures, extending the equipment's service life and contributing to the stable operation of the entire system. It should be understood that the intermediate cooler 5 is an optional device and can be set up or not as needed. The intermediate cooler 5 can cool the material coming out of the cooling section 102 and the sorting extractor 2 at the same time, or it can be used alone to cool the material coming out of the cooling section 102 or the material coming out of the sorting extractor 2. The specific connection and installation can be based on actual needs.

[0042] A bucket elevator 6 is installed on the pipeline connecting the small particle outlet of the sorting screen 4 and the granulation section 101. The bucket elevator 6 vertically lifts and transports the small granular fertilizer screened by the sorting screen 4 to the granulation section 101. This design solves the space limitation problem that may be encountered in horizontal conveying and ensures that the small granular fertilizer can be smoothly returned to the starting stage of the granulation process. The bucket elevator 6 can realize continuous material conveying, ensuring the smooth operation of the entire system and improving production efficiency. Due to its good material handling performance, the bucket elevator 6 can effectively prevent pipeline blockage and maintain the stability and reliability of the system.

[0043] A product cooler 7 is connected to the large particle outlet to discharge the granular fertilizer product through its output port. The product cooler 7 provides an additional cooling environment for the pre-cooled large granular fertilizer, ensuring it reaches suitable storage and transportation temperatures and preventing quality degradation or safety hazards caused by excessively high temperatures. The granular fertilizer processed by the product cooler 7 can be directly output as a finished product, ready for market entry or further processing such as packaging. This step helps improve the product's appearance quality and physical properties, such as hardness and roundness.

[0044] In some specific embodiments of the fluidized bed granulation system of this utility model that can improve granulation efficiency, the fluidized bed granulation system that can improve granulation efficiency also includes an atomizing fan 8, the atomizing fan 8 is connected to an atomizing air preheater 9 through a pipeline, and the atomizing air preheater 9 is connected to the fluidized bed granulation equipment 1 through a pipeline.

[0045] The atomizing fan 8 provides the necessary airflow pressure to break the molten fertilizer into fine droplets, thereby promoting granulation. The atomizing air preheater 9 heats the atomizing air from the atomizing fan 8, ensuring it reaches the appropriate temperature for better contact with the molten fertilizer, helping to form uniform small seed particles and accelerating the drying process. Specifically, the airflow generated by the atomizing fan 8 is transported through pipelines to the atomizing air preheater 9, where it is preheated before entering the granulation section 101 of the fluidized bed granulator 1. The preheated atomizing air acts on the molten fertilizer sprayed from the granulation nozzle within the granulation section 101, breaking it into fine droplets. This also helps control the temperature of the granulation environment, preventing granules from sticking together due to excessive temperature.

[0046] Furthermore, the fluidized bed granulation system, which can improve granulation efficiency, also includes a fluidizing blower 10. The fluidizing blower 10 is connected to a fluidizing air preheater 11 via pipeline, and the fluidizing air preheater 11 is connected to the fluidized bed granulation equipment 1 via pipeline. The fluidizing blower 10 can provide sufficient airflow to support the particles, keeping them in a suspended state, i.e., "fluidization," to facilitate mass and heat transfer. The fluidizing air preheater 11 preheats the fluidizing air from the fluidizing blower 10, adjusting it to a temperature suitable for the granulation process, ensuring that the particles can grow under optimal conditions. Specifically, the airflow provided by the fluidizing blower 10 is also connected to the fluidizing air preheater 11 via pipeline. After preheating here, it is sent to the granulation section 101 and cooling section 102 of the fluidized bed granulation equipment 1 through another set of pipelines. In the granulation section 101, the preheated fluidizing air helps maintain the fluidized state of the material, ensuring uniform particle distribution and growth. In the cooling section 102, it is mainly used to remove heat and help cool down the large granular fertilizer.

[0047] In some specific examples, the exhaust gas outlet of the fluidized bed granulation equipment 1 is connected to a dust collector 12, and the dust collector 12 is connected to an induced draft fan 13 to discharge the exhaust gas from the fluidized bed granulation equipment 1 through the dust collector 12 and the induced draft fan 13. It is understood that this example specifically designs an exhaust gas treatment system to ensure environmental protection and operational safety during the production process. The exhaust gas treatment system consists of a dust collector 12 and an induced draft fan 13, used to treat the exhaust gas discharged from the fluidized bed granulation equipment 1. Specifically, during the fluidized bed granulation process, exhaust gas containing dust and other pollutants is generated due to the heating and evaporation of the material. This exhaust gas is first discharged from the exhaust gas outlet of the fluidized bed granulation equipment 1, and then directly enters the dust collector 12 through pipelines. Inside the dust collector 12, the exhaust gas undergoes efficient dust removal treatment, and most of the dust and particulate matter are effectively captured, reducing the impact on the environment. Depending on the specific application scenario, different types of equipment can be used for the dust collector, such as bag filters, electrostatic precipitators, or wet scrubbers. After being purified by the dust collector 12, the exhaust gas is safely discharged into the atmosphere through the pipeline system under the action of the induced draft fan 13. The suction force provided by the induced draft fan 13 ensures the smooth flow of the exhaust gas throughout the entire treatment process. At the same time, the induced draft fan 13 is an optional device, and the air volume can be adjusted according to actual needs to select whether the induced draft fan 13 is needed, ensuring the best treatment effect.

[0048] The granulation method of the fluidized bed granulation system of this utility model, which can improve granulation efficiency, includes: feeding small granular fertilizer seed crystals into the granulation section 101 of the fluidized bed granulation equipment 1; spraying molten fertilizer liquid onto the granulation section 101 based on a fertilizer melt source to convert the small granular fertilizer seed crystals into large granular fertilizer particles, which then flow into the cooling section 102 of the fluidized bed granulation equipment 1; sorting the granular fertilizer particles flowing in the granulation section 101 that meet the particle size requirements based on a sorting extractor 2; and outputting the granular fertilizer particles that meet the particle size requirements sorted by the sorting extractor 2 and the granular fertilizer particles output from the cooling section 102.

[0049] A fluidized bed granulation method that can improve granulation efficiency also includes: granular fertilizer output from the separator 2 and cooling section 102 is sieved by a separating screen 4; small granular fertilizer sieved by the separating screen 4 is transported to the granulation section 101 as seed granules; and large granular fertilizer sieved by the separating screen 4 is output as the granular fertilizer product. Atomizing air is output into the fluidized bed granulation equipment 1 using an atomizing fan 8 and an atomizing air preheater 9 to form uniform droplets from the molten fertilizer sprayed within the fluidized bed granulation equipment 1. Fluidizing air is output into the fluidized bed granulation equipment 1 using a fluidizing fan 10 and a fluidizing air preheater 11 to maintain the granular fertilizer in a fluidized suspension state within the fluidized bed granulation equipment 1.

[0050] It is understood that the fluidized bed granulation method of this embodiment aims to provide a granulation method that can improve granulation efficiency. In the process of converting small granular fertilizer seeds into large granular fertilizer, fertilizer particles that meet the particle size standard are continuously output through the sorting extractor 2 to improve the contact between the non-compliant granular fertilizer particles and the molten fertilizer, thereby improving the efficiency of converting small granular fertilizer into large granular fertilizer.

[0051] First, small-particle fertilizer seed crystals are fed into the granulation section 101 of the fluidized bed granulator 1. A pump 3 draws molten fertilizer from a source and sprays it evenly into the granulation section 101 through a granulation nozzle. The molten fertilizer adheres to the small-particle fertilizer seed crystals, gradually forming large-particle fertilizer. As the granulation process continues, the granulated fertilizer moves towards the cooling section 102 of the fluidized bed granulator 1. During this process, a sorting extractor 2 sorts the granulated fertilizer flowing in the granulation section 101, separating out those with the required particle size. The granulated fertilizer with the required particle size sorted by the sorting extractor 2, along with the granulated fertilizer output from the cooling section 102, is transported out for further processing. The granular fertilizer output from the sorting extractor 2 and the cooling section 102 is screened using the sorting screen 4. The small granular fertilizer after screening is sent back to the granulation section 101 to continue to participate in the granulation process, while the large granular fertilizer after screening is output as the final product.

[0052] In the above process, as the sorting extractor 2 continuously sorts out the granular fertilizer that meets the particle size standard from the granulation section 101 of the fluidized bed granulation equipment 1, only the small granular fertilizer that does not meet the standard is retained to flow in the granulation section 101 and further sprayed and granulated into large granules. In this way, in the subsequent granulation section, since there is no large granular fertilizer involved in the flow, the amount of fertilizer melt sprayed onto the small granular fertilizer per unit area increases, which improves the efficiency of small granular fertilizer to large granular fertilizer. This results in more large granular fertilizer being output in the end. The large granular fertilizer sorted by the sorting extractor 2 and the granular fertilizer output from the cooling section 102 are output together, which increases the proportion of large granular fertilizer output from the fluidized bed and improves the efficiency of fluidized bed granulation.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A fluidized bed granulation system capable of improving granulation efficiency, characterized by, The fluidized bed granulation equipment (1) includes a fluidized bed granulator and a fluidized bed cooler. The fluidized bed granulator and the fluidized bed cooler form a granulation section (101) and a cooling section (102) respectively within the fluidized bed granulation equipment (1). The granulation section (101) is used to convert small granular fertilizer seeds into large granular fertilizer. The cooling section (102) is connected to the granulation section (101) to receive and cool the granular fertilizer converted by the granulation section (101). The granulation section (101) is provided with at least one sorting extractor (2). The sorting extractor (2) is used to sort the large granular fertilizer in the granulation section (101) and output it to the fluidized bed granulation equipment (1).

2. The fluidized bed granulation system capable of improving granulation efficiency according to claim 1, wherein, The granulation section (101) is provided with a seed inlet at a position away from the cooling section (102) for adding small granular fertilizer seed crystals to the granulation section (101); the granulation section (101) is provided with a plurality of sorting extractors (2), which are evenly spaced between the seed inlet and the cooling section (102).

3. The fluidized bed granulation system for improving granulation efficiency according to claim 1, characterized in that, The granulation section (101) is equipped with a granulation nozzle. The granulation nozzle is connected to a fertilizer melt source via a pipeline. The fertilizer melt source sprays fertilizer melt onto the granulation section (101) through the granulation nozzle to transform small granular fertilizer seeds in the granulation section (101) into large granular fertilizer.

4. The fluidized bed granulation system for improving granulation efficiency according to claim 3, characterized in that, The fertilizer melt source is a liquid tank containing fertilizer melt, and the liquid tank is connected to a delivery pump (3) via a pipeline. The delivery pump (3) is connected to the granulation section (101) via a pipeline.

5. The fluidized bed granulation system for improving granulation efficiency according to claim 1, characterized in that, The outlet of the cooling section (102) and the outlet of the sorting extractor (2) are both connected to the sorting screen (4) through pipelines. The sorting screen (4) includes a small particle outlet and a large particle outlet. The small particle outlet is connected to the granulation section (101) through pipelines, and the large particle outlet outputs granular fertilizer products.

6. The fluidized bed granulation system for improving granulation efficiency according to claim 5, characterized in that, An intermediate cooler (5) is provided on the pipeline connecting the outlet of the cooling section (102) and / or the outlet of the sorting extractor (2) to the sorting screen (4).

7. The fluidized bed granulation system for improving granulation efficiency according to claim 6, characterized in that, A bucket elevator (6) is installed on the pipeline connecting the small particle outlet of the dividing screen (4) and the granulation section (101). And / or, The large particle outlet is connected to a product cooler (7) so that the granular fertilizer product can be output through the outlet of the product cooler (7).

8. The fluidized bed granulation system for improving granulation efficiency according to any one of claims 1 to 7, characterized in that, The fluidized bed granulation system that can improve granulation efficiency also includes an atomizing fan (8), which is connected to an atomizing air preheater (9) via a pipeline, and the atomizing air preheater (9) is connected to the fluidized bed granulation equipment (1) via a pipeline. And / or, The fluidized bed granulation system that can improve granulation efficiency also includes a fluidizing blower (10), which is connected to a fluidizing air preheater (11) via a pipeline, and the fluidizing air preheater (11) is connected to the fluidized bed granulation equipment (1) via a pipeline. And / or, The exhaust outlet of the fluidized bed granulation equipment (1) is connected to a dust collector (12), and the dust collector (12) is connected to an induced draft fan (13) to discharge the exhaust gas of the fluidized bed granulation equipment (1) through the dust collector (12) and the induced draft fan (13).

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