In the agricultural input market, “Formula Fertilizer No. 7” is a frequently chosen option by farmers when purchasing fertilizers for the fruit enlargement period. However, it is not a nationally standardized number, but rather a custom-designed formula code used within the industry. As a specialized fertilizer designed specifically for the reproductive growth stage of crops, Formula Fertilizer No. 7 features “high potassium, low nitrogen, and medium phosphorus” as its core characteristics, precisely matching the nutrient requirements for fruit enlargement, coloring, and sweetening. It has become a key fertilizer for improving the yield and quality of fruits and cash crops, and is also a standard “fruit enlargement fertilizer” commonly used in the agricultural input industry.

The core advantage of Formula Fertilizer No. 7 lies in its scientific nutrient ratio. The classic formula ratios for mainstream Formula Fertilizer No. 7 in the industry are mostly 15-5-20, 16-6-22, etc., with the core characteristics of potassium content not less than 20%, nitrogen content moderate to low, and phosphorus content moderate. Potassium, known as a “quality element,” promotes the transport of photosynthetic products to fruits and seeds, effectively improving fruit sweetness, color, and firmness, and reducing fruit cracking and deformities. A low-nitrogen design prevents excessive vegetative growth, avoids nutrient competition, and ensures nutrient supply for reproductive growth. Appropriate phosphorus levels maintain root vitality, ensuring successful pollination and preventing empty seeds and fruit drop. Some manufacturers also add micronutrients such as calcium, magnesium, boron, and zinc to further enhance fertilizer efficiency.

Compared to other numbered fertilizer formulas, Formula 7 is highly targeted in its application. In the agricultural input industry, fertilizer formulations are typically categorized by crop growth stage and nutrient emphasis: Fertilizer No. 1 is high in nitrogen, low in phosphorus, and low in potassium, suitable for promoting seedling growth and leaf development; Fertilizer No. 2 has a balanced nitrogen, phosphorus, and potassium content, suitable for general supplemental fertilization throughout the crop’s growth period; Fertilizer No. 3 is high in phosphorus, medium in nitrogen, and low in potassium, primarily promoting root and flower development; while Fertilizer No. 7, with its “low nitrogen, medium phosphorus, and high potassium” formulation, is specifically targeted at critical reproductive stages such as fruit expansion, grain filling, and coloring, making it a dedicated fertilizer for the crop’s yield and quality formation stages. This clear positioning allows farmers to quickly and accurately select the right fertilizer.

Fertilizer No. 7 has a wide range of applications, especially suitable for crops with high potassium requirements. In fruits and vegetables such as watermelon, strawberries, tomatoes, grapes, and citrus, application significantly improves fruit expansion speed and fruit quality; in cash crops such as peanuts and soybeans during the pod-setting stage, and sweet potatoes and potatoes during the tuber enlargement stage, application increases yield and marketability; even in field crops such as rice and corn, application during the grain-filling stage and the late trumpet stage can improve grain plumpness. The optimal application time is during the fruit enlargement stage after flowering, typically 2-3 times consecutively, with an interval of 10-15 days, to maximize its effectiveness.

When applying Formula 7 fertilizer, attention must be paid to its suitability and scientific formulation. For chlorine-sensitive crops such as grapes, citrus, and sweet potatoes, potassium sulfate-based Formula 7 fertilizer should be chosen; for field crops, potassium chloride-based formula can be used to reduce planting costs. It is mainly used as a top dressing or fertigation fertilizer and cannot replace base fertilizer; it should be used in combination with organic fertilizer or balanced fertilizer as a base fertilizer. Foliar spraying with potassium dihydrogen phosphate and boron fertilizer during the fruit enlargement stage can further enhance the quality improvement effect. In addition, some manufacturers adjust the formula according to regional soil characteristics; for example, Formula 7 fertilizer for acidic soils in the south adds calcium and magnesium to adjust the acidity, while Formula 7 fertilizer for greenhouses uses a fully water-soluble formula suitable for drip irrigation. Farmers can choose according to their needs.

Manufacturing Precision: From Formula No. 7 to Professional Production

The widespread use of specialized formulas like Fertilizer No. 7 is enabled by sophisticated, flexible production systems. This precise formulation of “high potassium, low nitrogen, medium phosphorus” requires a manufacturing process that can accurately blend and shape specific nutrient ratios to meet exacting market demands.

The creation of such products is the domain of modern professional fertilizer manufacturing equipment. A typical npk fertilizer production line for this purpose would begin with a precise npk blending machine to mix raw materials to the exact No. 7 specification. This mixture is then formed into granules using specialized fertilizer granulator technology. Manufacturers might choose a disc granulation production line featuring a disc granulator (or disc granulator for shaping) for rounded particles, or a roller press granulator production line with a double roller press granulator for high-density granules. This entire sequence forms the core of the npk fertilizer production process. For producers also offering organic options, this specialized NPK line could be complemented by a separate organic fertilizer production line that begins with raw material processing using a windrow composting machine.

Ultimately, the availability of targeted fertilizers like Formula No. 7 is a direct result of advanced, adaptable manufacturing technology that can efficiently translate agronomic science into precise, high-quality products for farmers.

In summary, Formula 7 fertilizer is a high-potassium fertilizer specifically designed for the reproductive growth stage of crops. Its scientific nutrient ratio precisely addresses the nutrient requirements during the fruit enlargement stage. For farmers pursuing high and high yields, choosing the right No. 7 compound fertilizer and applying it scientifically can safeguard crop quality and yield, becoming an important aid to precision fertilization in modern agriculture.

Like a spring breeze bringing joy and abundant harvests, in March 2025, Zhengzhou Huaqiang Heavy Industry Technology Co., Ltd. (hereinafter referred to as “Huaqiang Heavy Industry”) successfully delivered and commissioned its customized disc granulation production line for an Australian client, officially putting it into operation. This project represents another significant achievement for Huaqiang Heavy Industry in its deep cultivation of the overseas high-end fertilizer equipment market. With its sophisticated process design, complete equipment configuration, and professional full-process service, it won high recognition from the Australian client, further demonstrating the core competitiveness of “Made in China” in the international market.

As a leading modern fertilizer equipment enterprise integrating R&D, production, sales, and after-sales service, Huaqiang Heavy Industry always focuses on customer needs. Relying on its strong technical strength, high-quality employee team, and professional CAD design center, it provides global clients with comprehensive one-stop solutions from plant planning and process design to equipment manufacturing, installation, commissioning, and formula optimization. This Australian client, focusing on the specific characteristics of local agricultural production, urgently needed a disc granulation production line that combined high efficiency, stable performance, and environmental standards for the large-scale production of organic and compound fertilizers. Leveraging its years of technological expertise in granulation equipment and extensive experience in overseas projects, Huaqiang Heavy Industry successfully secured the order by precisely addressing the client’s needs and repeatedly optimizing the design.

To ensure the production line was fully adapted to the local production conditions and raw material characteristics in Australia, the Huaqiang Heavy Industry project team conducted comprehensive customized research and development and design. This disc granulation production line is fully equipped and has a closed-loop process, covering the entire production chain from raw material pretreatment to finished product packaging: After the raw materials are orderly fed into the 1.5X2.5 meter loader feeding hopper, they are efficiently transferred through belt conveyors of different specifications such as 5 meters, 12 meters, and 8 meters, and enter a 40-type twin-shaft mixer for uniform mixing, ensuring accurate material ratio and uniform texture; the mixed material is rationally distributed by a distributor and sent to a 400-type flat die granulator and a 3.2-meter disc granulator for collaborative operation. The core equipment, the 3.2-meter disc granulator, adopts the optimized and upgraded disc angle design and transmission system of Huaqiang Heavy Industry, which has the advantages of high granulation rate, round and uniform particles, and flexible adjustment, and can accurately control the particle size according to customer needs; after granulation, the material is sent to a 1.2X12 meter dryer for low-temperature and high-efficiency drying via a 9-meter belt conveyor, and then transferred to a 1X10 meter dryer via a 10-meter belt conveyor. The cooling unit rapidly lowers the temperature, ensuring particle strength and stability. After cooling, the material is graded and screened by a 1.2×4.5 meter screener. Unqualified material is pulverized by a 500-type vertical crusher and then returned to the production line via a 12-meter belt conveyor for regranulation, forming a closed-loop system for resource recycling. Qualified finished products are temporarily stored in ton-bag silos and finished product silos, and finally standardized and packaged by an automatic packaging machine, achieving fully automated and efficient production.

Simultaneously, the production line is equipped with a comprehensive environmental protection system: a hot air furnace provides a stable heat source for the drying process, and together with a dust removal chamber, induced draft fan, water tank, and chimney, forms a highly efficient waste gas treatment system, ensuring that waste gas emissions meet standards and fully comply with stringent Australian environmental regulations. The entire production line incorporates the core technology of multi-functional compound fertilizer equipment independently developed by Huaqiang Heavy Industry, featuring a compact structure, small footprint, reliable operation, low energy consumption, and low dust entrainment, fully demonstrating the company’s strong capabilities in equipment integration and process optimization.

During the project implementation, Huaqiang Heavy Industry assembled a professional team composed of technical experts and construction personnel, who traveled across the hemisphere to the construction site in Australia. The team overcame multiple challenges, including geographical differences, complex construction environments, and varying technical standards. They strictly adhered to construction specifications and timelines to advance equipment installation and commissioning, while also providing professional operation training and technical guidance to the client, ensuring the production line quickly reached a stable operating state. During the trial operation, all aspects of the production line operated smoothly. Material handling efficiency, pellet forming quality, and environmental emission standards far exceeded customer expectations. Customer representatives highly praised Huaqiang Heavy Industry’s technical strength, product quality, and after-sales service: “Huaqiang Heavy Industry’s production line not only met our needs for large-scale production but also performed exceptionally well in environmental protection and energy conservation. The professional team and attentive service ensured our peace of mind throughout the process.” Zhengzhou Huaqiang Heavy Industry Technology Co., Ltd. has been deeply involved in the fertilizer equipment field for many years, specializing in a series of equipment including ground-mounted compost turners, trough compost turners, crushers, dryers, coolers, screening machines, and packaging machines. They can customize organic fertilizer production lines ranging from 10,000 to 500,000 tons. Their products cover all parts of China and are exported to many countries and regions, providing high-quality organic waste harmless treatment solutions for organic and inorganic bio-fertilizer plants and wastewater treatment plants worldwide. The successful delivery of this Australian disc pelletizing production line project is another important milestone in the company’s overseas market expansion, further consolidating its brand influence in the international fertilizer equipment market.

Adhering to the corporate tenet of “market-oriented, innovation-driven development, quality-based survival, and customer trust gained through comprehensive after-sales service,” Huaqiang Heavy Industry will continue to increase R&D investment, optimize product performance and process solutions, and enhance its customized service capabilities. In the future, the company will continue to actively expand into overseas markets, creating greater value for global customers with more advanced technology, more reliable products, and more professional services, allowing “Made in China” to win more applause and recognition on the international stage.

A Complete System from Raw Material to Finished Product

This successful Australian project highlights Huaqiang Heavy Industry’s ability to deliver a complete organic fertilizer production line. The supplied organic fertilizer disc granulation production line is a key module that transforms raw organic matter into uniform, market-ready fertilizer granules.

However, this granulation line is just one stage in a holistic manufacturing system. It is designed to process high-quality compost produced through a controlled organic fertilizer fermentation process. This upstream fermentation typically relies on efficient fermentation composting turning technology to produce stable, mature organic matter. For clients whose raw materials require a different physical form, Huaqiang can also integrate a flat die pelleting machine into the production flow. Together, these technologies—from turning and fermentation to organic fertilizer production granulation—form a seamless, end-to-end solution for converting organic waste into valuable fertilizer.

By mastering and integrating each critical stage, Huaqiang Heavy Industry provides clients with a scalable and efficient pathway to participate in the growing global organic fertilizer market.

We warmly welcome people from all walks of life to visit, guide, and discuss business with us, and work together to create a new blueprint for green agricultural development!

In November 2025, Zhengzhou Huaqiang Heavy Industry Technology Co., Ltd. successfully completed the installation and commissioning of a roller extrusion + drum granulation composite production line tailored for a Turkish client, officially entering the stage of large-scale production. This production line innovatively integrates the dual core technologies of roller extrusion granulation and drum granulation, consolidating the entire chain from raw material pretreatment, precise batching, composite granulation, drying and cooling, coating and screening, to finished product packaging. With a robust configuration of 6 roller granulators + drum granulators, a highly automated process design, and quality standards adapted to the Eurasian market, it has become a benchmark project for Chinese high-end fertilizer equipment in overseas markets, providing Turkish fertilizer producers with a customized solution that combines flexibility and scalability.

Production Line Configuration and Core Process Analysis

The entire production line follows a closed-loop logic of “refined raw material pretreatment – precise batching and mixing – composite granulation – post-processing and finishing – standardized finished product output.” The equipment layout is scientifically compact, with seamless connections between units. The synergistic application of dual granulation processes provides dual guarantees for product quality and production capacity, fully meeting the diverse fertilizer production needs of Turkey.

Raw Material Pretreatment and Precision Batching Unit: Laying a Solid Foundation for Production

Multi-dimensional Crushing Processing: The production line is equipped with four raw material bins, which can store nitrogen, phosphorus, and potassium main raw materials and mineral auxiliary materials respectively. The raw materials are transferred via a 7-meter belt conveyor to the dual crushing system—a cage crusher and a new type of roller crusher working in tandem. Cage crushers are used for coarse crushing of large raw materials, reducing particles ≤100mm in diameter to ≤20mm. The new roller crusher performs fine crushing, employing a high-strength, wear-resistant roller shaft design. Through the squeezing and shearing action between the rollers, the coarsely crushed raw materials are further pulverized to uniform particles ≤3mm, achieving a crushing efficiency of 8 tons/hour, meeting the stringent fineness requirements of various granulation processes. The crushing stage is equipped with a cyclone dust collector and induced draft fan, achieving a dust collection efficiency of 99% and a dust emission concentration ≤10mg/m³, complying with EU environmental standards.

Precise batching and uniform mixing: The crushed raw materials are conveyed to a 5-bin batching machine via 9-meter and 7-meter belt conveyors. Each bin is equipped with a high-precision metering screw conveyor. Combined with a PLC intelligent control system, the feed rate of each raw material can be automatically adjusted according to the preset formula, with a batching error ≤0.8%, ensuring accurate fertilizer nutrient ratios. The batched materials are fed into a 40-type twin-shaft mixer via a 12-meter belt conveyor. The equipment employs an anti-rotating blade design with a wear-resistant coating on the blade surface. During mixing, the materials undergo strong convection, shearing, and tumbling motions, resulting in a mixing uniformity error of ≤2%, providing a homogeneous raw material foundation for the subsequent dual granulation process.

Core Composite Granulation Unit: Dual Processes Create High-Quality Granules

Roller Extrusion Granulation Pretreatment: The mixed materials are precisely fed to six 2.0-type roller extrusion granulators via a 3-meter disc feeder. The feeder utilizes variable frequency speed regulation and automatic material level control technology to ensure uniform feeding to all six granulators. This type of granulator adopts a high-strength roller design, with roller skins made of high-chromium alloy. After quenching treatment, the hardness reaches HRC62 or higher, exhibiting extremely high wear resistance. The extrusion pressure can be precisely controlled within the range of 8-18MPa, compressing materials into uniformly dense flaky granules with a stable granulation rate exceeding 93%, providing a high-quality “masterbatch” foundation for subsequent drum granulation. Six granulators operate in parallel, each with a capacity of 2.5 tons per hour, achieving a pre-processing capacity of 15 tons per hour through combined operation, significantly improving overall production efficiency.

Drum granulation molding optimization: The flaky granules extruded by the rollers are transferred to the Φ1.6X6 meter drum granulator via 5-meter, 7-meter, and 10-meter belt conveyors. This equipment is the core of the composite granulation process. The inner wall of the drum is lined with special wear-resistant plates, and the spiral layout of the lifting plates drives the material to continuously tumble within the drum. Simultaneously, the melting tank heats and melts coating agents, binders, and other auxiliary materials, which are then evenly sprayed onto the material surface through an atomizing spraying system. This further rolls the flaky granules into round, uniform spherical particles, with a particle size that can be precisely controlled within 3-5mm. The drum granulator uses a variable frequency speed control design, allowing for flexible adjustment of the rotation speed (10-20 r/min) according to the granulation effect. The spherical granulation rate reaches over 95%, and the granule compressive strength reaches 2.8MPa. It is not prone to pulverization and fully meets the needs of long-distance transportation and field application in Eurasia.

Post-processing and Finished Product Output Unit: Quality Upgrade and Efficient Delivery

Drying, Cooling, and Shaping: Wet granules from drum granulation are conveyed via a 15-meter belt conveyor to a Φ1.5X15-meter dryer. A hot air furnace provides a stable heat source, and the drying temperature is precisely controlled between 70-90℃. A hot air circulation process reduces the granule moisture content from 30% to below 12%, with a drying uniformity error of ≤3%. Subsequently, the granules are conveyed via 7-meter and 5-meter belt conveyors to a Φ1.5X15-meter cooler. A counter-current cooling process rapidly lowers the granule temperature to room temperature (±5℃), further improving granule hardness and storage stability. The cooling efficiency reaches 18 tons/hour.

Coating and Screening Optimization: Cooled granules are conveyed via a 13-meter belt conveyor to a Φ1.2X5-meter coating machine. A special coating agent is evenly applied to the granule surface using atomized spraying technology, forming a dense protective film that effectively improves the fertilizer’s resistance to moisture absorption, anti-caking properties, and slow-release nutrient effect. The coated granules are transferred to a Φ1.8X6 meter screening machine via a 10-meter belt conveyor. A double-layer screen design separates the qualified granules. Unqualified granules are crushed by a 60-type vertical crusher and then returned to the raw material mixing front end via 9-meter and 7-meter return conveyors, re-entering the granulation process. Material utilization reaches 99%.

Finished Product Storage and Automated Packaging: Qualified granules are temporarily stored in a finished product silo equipped with a material level monitoring system and dehumidification and ventilation devices to ensure stable product storage. The packaging process utilizes an automatic packaging machine that supports rapid switching between various sizes such as 25kg and 50kg. It employs gravity metering principles with high-precision sensors, achieving a metering error of ≤±0.1kg and a packaging speed of 150 bags/hour. Combined with a gantry crane and transfer system, it enables rapid warehousing and shipping of finished products.

Environmental Protection and Intelligent Control Unit: Precise Control of Green Production

Comprehensive Environmental Protection System: The production line is equipped with a complete waste gas treatment system. Waste gas from the hot air furnace undergoes multi-stage purification treatment via cyclone dust collectors and spray towers before being discharged in compliance with standards. Dust generated in each production stage is centrally collected by induced draft fans and sent to the dust removal system, achieving zero dust leakage. The water tank and spray tower are designed in conjunction to effectively treat harmful components in the waste gas, and all emission indicators comply with EU environmental regulations.

Intelligent Centralized Control: The production line integrates a central control room and a complete set of electrical control cabinets, adopting a PLC intelligent control system that can monitor the operating parameters of each piece of equipment in real time (speed, pressure, temperature, material level, etc.), supporting automatic fault alarms, data recording, and remote diagnostic functions. The walking platform facilitates operators’ maintenance and repair of high-level equipment, achieving precise control and safe and efficient operation of the entire production process.

Core Advantages and Regional Adaptability of the Production Line

Innovative Composite Granulation Process: The combination of roller extrusion and drum granulation ensures both particle density and strength, while also achieving rounded particle shape. Product quality far surpasses that of single-granulation processes, meeting the demands of the high-end fertilizer market.

Precise Adaptation to Regional Conditions: Core equipment utilizes high-temperature, wear-resistant, and corrosion-resistant materials, adapting to the high-temperature and dry characteristics of Turkey’s Mediterranean climate. The production line design complies with EU technical standards and environmental requirements, facilitating customer expansion into the Eurasian market.

High Efficiency, Energy Saving, and Cost-Effectiveness: The coordinated configuration of six roller granulators and drum granulators achieves a stable production capacity of 20 tons/hour, with an annual capacity of up to 150,000 tons. The entire process employs energy-saving motors and optimized process design, reducing energy consumption by 15% compared to conventional production lines with the same capacity, significantly lowering customer production costs.

The successful commissioning of the roller extrusion + drum granulation production line in Turkey not only demonstrates Zhengzhou Huaqiang Heavy Industry Technology Co., Ltd.’s comprehensive strength in the R&D of composite granulation equipment and the implementation of high-end overseas projects, but also provides efficient and stable equipment support for the modernization of agriculture in the Eurasian region. In the future, Huaqiang Heavy Industry will continue to focus on the diversified needs of global customers, optimize product performance and service solutions, and provide customized high-end fertilizer production solutions for more countries and regions, allowing “Made in China” to shine even brighter in the international market.

Synergizing Technologies for Superior Product Quality

The successful delivery of this composite granulation line to Turkey exemplifies Huaqiang Heavy Industry’s expertise in integrating multiple advanced technologies into a single, high-output fertilizer production machine system. This project highlights a sophisticated approach to the modern npk fertilizer manufacturing process, where product quality is paramount.

The line’s innovation lies in the strategic combination of two proven granulation methods. The initial stage utilizes a roller press granulator production line configuration, where multiple fertilizer compaction machine units perform dry fertilizer granules compaction to create a dense pre-form. This is seamlessly followed by a finishing stage of drum granulation in a rotary drum granulator, which rounds and polishes the particles. This hybrid process leverages the strengths of both the fertilizer compactor for density and the drum for shape, creating a superior final product that meets the stringent demands of the high-end Eurasian market within an efficient npk manufacturing process.

This project underscores a key trend in professional fertilizer manufacturing: the intelligent integration of complementary technologies to achieve product characteristics that single-process lines cannot match, providing clients with a distinct competitive advantage.

This innovative carbon-based fertilizer disc + drum granulation production line integrates two processes: “disc pre-granulation + drum finishing.” Specifically designed for the granulation needs of carbon-based raw materials (straw charcoal, bamboo charcoal, biochar, etc.), it solves the granulation pain points of lightweight and poor binding properties of carbon-based raw materials through a closed-loop process of “pre-forming + densification.” This enables large-scale, high-quality production of carbon-based fertilizer, suitable for green development scenarios such as ecological agriculture and organic farming.

Production Line Configuration and Core Details

Raw Material Pre-treatment Unit: Laying the Foundation for Granulation

(I) Raw Material Storage and Precision Batching

Multi-Compartment Storage System: Equipped with 5 raw material compartments (total volume 120m³), storing biochar, organic fertilizer fermentation material, nitrogen, phosphorus, and potassium inorganic fertilizer, binders (such as bentonite and starch), and trace elements respectively. The compartments are made of carbon steel with an anti-corrosion coating, and vibrators and star-shaped unloaders are installed at the bottom to prevent bridging and clogging of carbon-based raw materials.

Precision Batching Device: Employs a frequency-controlled screw feeder, with 5 batching systems operating synchronously, achieving a batching error of ≤±1%. The proportion of biochar can be flexibly adjusted (30%-60%), the ratio of inorganic to organic fertilizer is customized according to crop needs, and the binder addition is controlled at 3%-8% to ensure pellet formation rate.

(II) Raw Material Mixing and Moisture Adjustment

Twin-Shaft Mixer: A 50-type twin-shaft mixer is used. The impellers employ an anti-rotation design, driving strong convection and shearing of the materials to thoroughly mix the charcoal-based raw materials with other components, achieving a mixing uniformity error of ≤2%. The mixer is equipped with a spray humidification device to precisely adjust the raw material moisture content to 28%-35% (suitable humidity for the charcoal-based raw materials), preventing clumping due to excessive moisture or insufficient adhesion due to insufficient moisture.

Pulverization Pretreatment: If large lumps (particle size > 10mm) of biochar exist, they are first crushed to ≤3mm using a 400-type vertical pulverizer to ensure uniform raw material fineness and improve subsequent granulation results. The pulverizer is equipped with a cyclone dust collector to collect and reuse the crushed dust, achieving a material utilization rate of 99%. II. Core Dual Granulation Unit: Carbon-Based Particle Densification Forming

(I) Disc Pre-granulation: Key to Lightweight Material Pre-forming

Core Equipment Selection: Two Φ3.2×1.2 meter disc granulators (3-5 tons per hour per unit), with an adjustable inclination angle of 45°-55° and a rotation speed controlled at 20-30 r/min. The discs are lined with wear-resistant rubber plates to prevent wear from the carbon-based raw materials and enhance material adhesion.

Pre-granulation Process Details: The mixed raw materials are fed into the disc granulator. Through the centrifugal force and friction generated by the rotating disc, spherical wet particles with a diameter of 5-8 mm are formed (granulation rate ≥85%). A scraper is installed at the edge of the disc to promptly clean material adhering to the wall, and a spray device replenishes moisture in real time to ensure that the pre-formed particles are round and uniform, laying the foundation for drum finishing.

(II) Rotary Drum Granulation: Particle Densification Upgrade

Core Equipment Configuration: One Φ2.2×10 meter rotary drum granulator (6-10 tons per hour) is used, precisely matched with the capacity of the disc granulator. The inner wall of the drum is lined with wear-resistant ceramic plates, combined with a spiral layout of lifting plates, driving the material through a “tumbling-rolling-collision” motion to achieve particle densification.

Refinement Process Highlights: A spray device is installed inside the drum to replenish a small amount of binder solution, further rolling the pre-formed granules into dense granules of 3-6mm, increasing the particle strength from 1.2MPa to over 2.5MPa, solving the problem of easy pulverization of carbon-based granules. The drum speed is adjustable from 10-18 r/min, and the material residence time is 8-12 minutes to ensure dense and uniform particles.

III. Post-processing Unit: Quality Optimization and High-Efficiency Output

(I) Drying and Cooling Curing

Low-Temperature Dryer: Equipped with a Φ1.8×18 m drum dryer, using hot air circulation heating, the drying temperature is controlled at 70-90℃ (to avoid high temperature damage to carbon-based nutrients), reducing the particle moisture content from 30% to below 12%. The dryer has a built-in staggered lifting plate layout, ensuring uniform heating of the carbon-based particles, with a drying uniformity error ≤2%.

Dual-Stage Cooler: Employing a “first-stage counter-current cooling + second-stage co-current cooling” process, the particle temperature is first reduced from 70-80℃ to below 40℃ by a Φ1.6×15 m counter-current cooler, and then cooled to room temperature ±3℃ by a Φ1.2×12 m co-current cooler, further improving particle strength and moisture resistance. The cooler is equipped with a pulse dust collector to collect dust for recycling.

(II) Grading and Finished Product Processing

Grading and Screening Machine: A Φ1.5×6.0 meter drum screen with a double-layer screen design (upper layer aperture 6mm, lower layer aperture 3mm) is used to screen out qualified particles (3-6mm). Unqualified particles are returned to the disc granulator for reprocessing via a return conveyor belt, achieving a material utilization rate of 98%.

Anti-caking Treatment: When the screened finished particles are conveyed via conveyor belt, 0.1%-0.2% of an anti-caking agent (such as talc powder) is sprayed on them to ensure even mixing and prevent clumping during storage.

(III) Finished Product Storage and Packaging

Finished Product Silos: Two 100m³ sealed finished product silos are provided, equipped with dehumidification and ventilation devices to maintain a relative humidity of ≤60% to prevent the carbon-based fertilizer from absorbing moisture. A quantitative discharge device is installed at the bottom of the silo to achieve continuous and stable discharge.

Automated Packaging: Utilizing a dual-station automatic packaging scale, supporting rapid switching between 25kg and 50kg specifications, with a measurement error ≤ ±0.2kg and a packaging speed of 100 bags/hour. The packaging machine is equipped with a dust cover to reduce dust emissions, and the fully automated operation minimizes manual intervention.

Environmental Protection and Intelligent Control Unit: Stable Green Production

(I) Environmental Treatment System

Dust Treatment: Each dust-generating stage of the production line (crushing, screening, packaging) is equipped with a pulse dust collector, with a total processing air volume of 18000m³/h. Dust emission concentration ≤10mg/m³, meeting national environmental protection standards.

Wastewater Treatment: A small amount of cleaning wastewater during production is treated in a sedimentation tank and then recycled for raw material humidification, achieving zero wastewater discharge.

(II) Intelligent Control System

Integrated PLC central control system, real-time monitoring of key parameters such as ingredient ratio, moisture content, granulation speed, and drying temperature, supporting automatic fault alarms and data recording (storage period ≥90 days). The system supports manual and automatic mode switching and can dynamically adjust process parameters according to raw material characteristics to ensure stable production.

Core Advantages and Application Value of the Production Line

Breakthrough in Granulation Pain Points: The combined disc and drum granulation processes solve the problems of poor adhesion and low granulation rate of carbon-based raw materials. Granulation formation rate is consistently above 90%, with a strength exceeding 2.5 MPa, making it resistant to storage and transportation and less prone to pulverization.

Flexible Capacity: Hourly capacity covers 6-10 tons, with an annual capacity of 50,000-80,000 tons (based on 300 days of operation per year and 8 hours per day), adapting to the production needs of enterprises of different sizes.

Superior Product Quality: Carbon-based raw materials and nutrients are uniformly integrated, resulting in rounded granules with good flowability, facilitating mechanized fertilization. The slow-release characteristics of carbon-based components can improve fertilizer utilization by more than 30% and reduce nutrient loss.

Green, Environmentally Friendly, and Energy-Saving: High dust recovery and utilization rate; energy consumption is reduced by 12% compared to conventional single-process granulation production lines, meeting the requirements of green agricultural production.

A Specialized Link in a Broader Manufacturing Ecosystem

This carbon-based fertilizer granulation line represents a significant advancement in processing challenging, lightweight organic materials into high-quality, market-ready fertilizers. Its innovative dual-granulation approach sets a new standard for product quality and production efficiency in the niche of carbon-enriched soil amendments.

This specialized line is a prime example of professional fertilizer manufacturing equipment designed for a specific purpose. It exists within a larger ecosystem of fertilizer production technologies. For instance, the disc granulator used here is a key component in a disc granulation production line and can also serve as a disc granulator for shaping in other contexts. While this line produces organic-carbon blends, its principles complement other systems. A complete organic fertilizer production line might begin with a windrow composting machine to produce the base compost. For mineral-based production, an npk fertilizer production line would utilize an npk blending machine and different granulation technologies like a roller press granulator production line or a double roller press granulator as part of the npk fertilizer production process. Each type of fertilizer granulator serves a unique role in the diverse portfolio of modern fertilizer manufacturing.

Thus, this carbon-based line is not an isolated solution but an integral part of a comprehensive toolkit that allows manufacturers to meet the growing global demand for both specialized organic inputs and conventional high-analysis fertilizers.