The Secrets of the Double Roller Press Granulator in an Organic Fertilizer Production Line

In the granulation process of an organic fertilizer production line, the double roller press granulator, due to its high efficiency and environmentally friendly features, is a core piece of equipment. It uses the principle of physical extrusion to transform loose organic fertilizer raw materials into uniform granules, meeting the needs of fertilizer storage, transportation, and application. Its operation process can be divided into three stages: raw material pretreatment, extrusion molding, and granulation.

Raw material pretreatment is the foundation of granulation. Fermented and crushed organic fertilizer raw materials first enter the batching system, where they are mixed with auxiliary materials in a controlled ratio to achieve a moisture content of 20%-30% and a particle size uniformity of over 80%. The raw materials are then conveyed to the feed inlet of the double-roller extrusion granulator, where they are pushed at a constant speed between two counter-rotating extrusion rollers by a screw feeder. The feeder speed can be adjusted according to the raw material characteristics to ensure a stable feed rate and avoid overloading the equipment due to excessive raw materials or affecting granulation efficiency due to insufficient raw materials.

Extrusion molding is the core step. The surfaces of the two rollers of a double-roller extrusion granulator are equipped with evenly distributed depressions of the same shape. Common shapes include circular and oval. A motor drives the rollers in counter-rotating motion through a reduction gear, generating a strong extrusion force between the rollers, compressing the raw material into the depressions. Under this pressure, the organic particles in the raw material are tightly bound together, forming lumps that conform to the shape of the depressions. This process requires no binder, relying entirely on the raw material’s inherent viscosity and extrusion force to form the product. This reduces costs while ensuring the natural properties of the organic fertilizer. The extrusion force can be adjusted to the desired granule hardness, typically within a range of 15-30 MPa.

The final stage is granulation. After the lumps fall through the gap between the rollers, they enter the crushing and screening system. The crusher breaks down the lumps, and the screen separates the organic fertilizer granules into acceptable particle sizes (generally 2-8 mm). Unacceptable large lumps or fines are returned to the raw material system for recycling, increasing raw material utilization to over 95%.

The double roller press granulator plays a key role in the organic fertilizer production line with its advantages of continuous operation, low energy consumption and high particle strength, and provides equipment support for promoting the development of green agriculture.

How does a rotary drum granulator work in an organic fertilizer production line?

In an organic fertilizer production line, a rotary drum granulator is the core equipment for converting powder into granules. Its operating principles revolve around material agglomeration and granulation. Through a combination of physical and mechanical processes, it transforms fermented organic raw materials into granular products that are easy to store, transport, and apply.

After the equipment is started, fermented and pulverized organic materials (such as decomposed cow dung and straw powder) are introduced into the inclined drum of the rotary drum granulator along with an appropriate amount of binder (usually water or starch solution). The drum rotates at a constant speed of 10-15 revolutions per minute. Lifting plates on the inner wall of the drum continuously scoop up and drop the material, creating continuous agitation and mixing. During this process, the binder moistens the surface of the raw material particles, forming a sticky interface and paving the way for particle agglomeration.

As the drum rotates continuously, the material gradually forms tiny “master particles” under the combined effects of gravity, centrifugal force, and friction. These masterbatch particles continuously roll within the drum, attracting surrounding powdered raw materials like a snowball, gradually increasing in size. Furthermore, the drum’s tilt angle (typically 3-5°) ensures that the material moves slowly toward the discharge end, preventing accumulation within the drum and ensuring that each particle is evenly stressed and grows.

To ensure pellet quality, the drum granulator also uses a temperature control system to regulate the drum temperature (typically between 40-60°C). This prevents excessive moisture content from causing pellet adhesion, while also preventing low moisture content from affecting agglomeration. When the pellets reach the preset size (typically 2-5mm, controlled by adjusting the drum speed and residence time), they are discharged from the discharge end and enter the subsequent drying and cooling processes.

Compared with other granulation equipment, the advantages of the rotary drum granulator are large processing capacity (a single device can produce 50-200 tons of fertilizer per day), high particle strength (compressive strength can reach 15-30N), and strong adaptability to raw materials. Whether it is poultry and livestock manure, straw or mushroom residue, it can be granulated stably. It is an indispensable key equipment in large and medium-sized organic fertilizer production lines.

How to Improve the Efficiency of the Granulator in an Organic Fertilizer Production Line

As the core equipment in an organic fertilizer production line, the efficiency of the granulator directly determines the production capacity and product quality of the entire line. Improving granulator efficiency requires precise attention to multiple aspects, including raw materials, equipment, operation, and maintenance, to overcome common production bottlenecks.

Proper raw material pretreatment is fundamental. Organic fertilizer raw materials have complex compositions. Improper moisture and particle size can easily lead to clogging or loose granules. Moisture content should be controlled between 25% and 35%. If the moisture content is too high, a dryer should be used for dehydration; if it is too low, water spraying should be used for conditioning. A pulverizer should be used to control the particle size to 80-100 mesh to prevent impurities from entering the machine. Binders such as bentonite and starch should be added in appropriate proportions to enhance raw material cohesion, reduce powder waste, and increase granulation success rates.

Scientifically controlling equipment parameters is a key measure. Different granulators (such as rotary drum granulators and double roller press granulators) require matching parameters. For rotary drum granulators, the drum speed (usually controlled at 15-25 rpm) and tilt angle (3-5°) must be adjusted according to the raw material characteristics; for double roller press granulators, the roller pressure and gap must be appropriately set. Furthermore, the feeder must ensure a uniform feed rate to prevent material fluctuations that could cause the granulator to “run out” or “stuck,” maintaining stable equipment operation.

Enhanced routine maintenance is essential. During granulator operation, clean the inner wall of the drum or the extrusion die of residual material every shift to prevent scaling that could affect performance. Check bearing lubrication weekly and refill with high-temperature grease to prevent friction overheating and reduce the speed. Replace worn scrapers and liners monthly to prevent component aging and reduced molding efficiency. Maintain an equipment maintenance log to record parameters and faults to facilitate troubleshooting and reduce downtime.

Optimizing supporting processes can further improve efficiency. Linking the pelletizer with upstream and downstream processes, using sensors to monitor raw material data in real time, and adjusting upstream equipment parameters to ensure quality raw materials. Optimizing the drying and pelletizing speeds prevents pellet accumulation and moisture, minimizing secondary processing, and maximizing pelletizer efficiency.

In summary, improving pelletizer efficiency requires a balanced approach of “source control, process optimization, and ongoing maintenance.” Through refined management, production and quality can be increased while extending equipment life, ultimately creating greater profitability for the production line.

How does a rotary drum granulator work in an organic fertilizer production line?

In organic fertilizer production lines, a rotary drum granulator is the core equipment for raw material formation. It has become a mainstream choice because it meets the cohesiveness and granularity requirements of organic fertilizers such as livestock and poultry manure and composted straw. Its operation revolves around “raw material mixing – granule agglomeration – screening and output,” resulting in an efficient and stable mechanism.

The equipment primarily consists of an inclined drum (3°-5° inclination), a transmission system, a spray system, and a scraper assembly. Scrapers on the inner wall of the drum drive the material to tumble, while the spray system regulates moisture. The scraper removes material adhering to the drum wall to prevent clogging.

The first step is “raw material pretreatment and feeding.” Composted and crushed organic fertilizer raw materials (25%-35% moisture) are mixed with auxiliary materials such as clay in a suitable proportion and then fed into the drum through the feed port. The motor drives the drum to rotate at a low speed of 10-15 rpm. The scrapers repeatedly lift and drop the material, forming a uniform layer.

The second step is the core “granule agglomeration and formation” phase. A spray device applies a metered amount of water or adhesive, depending on the moisture content of the raw materials, to create a sticky surface. As the drum rotates continuously, the material particles agglomerate into small particles through collision, friction, and compression. These small particles further absorb the raw materials and grow to qualified granules of 2-5mm. The tilted design of the drum allows the particles to naturally move toward the discharge end, enabling continuous production.

The final step is “granule screening and optimization.” The formed granules are screened to separate fine powder from bulky material. The fine powder is returned to the granulator, while the bulky material is crushed and reused to ensure acceptable yields. Furthermore, a scraper cleans the drum wall of any residue in real time to ensure efficiency and prevent hardened residue from affecting subsequent production.

In short, the rotary drum granulator uses gentle physical agglomeration to adapt to the characteristics of organic fertilizer raw materials, efficiently producing uniform granules and providing a key guarantee for the stable operation of organic fertilizer production lines.

Scientific Maintenance of Organic Fertilizer Production Equipment

The stable operation of organic fertilizer production equipment is key to ensuring fertilizer quality and production efficiency. A scientific maintenance system can effectively extend equipment life and reduce the risk of failure. Targeted maintenance measures are required for equipment throughout the entire process, from pretreatment to finished product packaging, tailored to its characteristics.

Maintenance of pretreatment equipment focuses on preventing blockage and wear. As the first step in processing raw materials such as straw and manure, the crusher requires daily inspection for blade wear and weekly sharpening to prevent blunting and reduced pulverization efficiency. Screening machines require regular cleaning of residual fiber debris and monthly inspection of screen tension to prevent vibration-induced loosening that reduces screening accuracy. For conveying equipment, special attention should be paid to the tightness of the conveyor belt and the lubrication of the rollers to prevent failures caused by frictional overheating.

Granulating equipment requires timely cleaning and maintenance. The disc granulator‘s disc should be cleaned of residual particles daily and coated weekly with an anti-stick coating to prevent material from clumping and sticking. Bearings should be lubricated with high-temperature resistant grease monthly to ensure smooth rotation. The roller surface of the roller granulator should be regularly inspected for wear and any dents should be repaired promptly to avoid compromising pellet quality.

Maintenance of post-processing equipment focuses on precision and safety. The hot air ducts of the drum fertilizer dryer should be cleaned of dust monthly to prevent blockages that affect thermal efficiency. The temperature sensor should be calibrated weekly to ensure precise control of the drying temperature. The fan filter of the cooler should be cleaned regularly to prevent debris from entering and affecting heat dissipation. The metering device of the packaging machine should be calibrated weekly, and the drive chain of the conveyor belt should be lubricated monthly to ensure accurate quantitative packaging.

Establishing an equipment maintenance mechanism provides long-term protection. Recording the time, content, and troubleshooting of each maintenance session can help identify recurring problems promptly. Operators should also receive professional training to ensure early resolution of minor faults and early prevention of major problems. Scientific maintenance not only reduces equipment failure rates but also ensures the continuity and stability of the organic fertilizer production line, providing reliable support for the green development of agriculture.

How to Choose the Right Double Roller Press Granulator for Farms

Due to its unique advantages, double-roller press granulators have become essential equipment for farms to process manure and produce organic fertilizer. When selecting a granulator, you need to consider multiple factors to ensure it meets your production needs.

First, you need to determine your production scale. Small and medium-sized farms have limited daily manure processing capacity, so choosing a small machine with an hourly capacity of 1-3 tons can meet daily granulation needs while avoiding idle equipment. Large-scale farms require a machine with an hourly capacity of 5 tons or more and strong continuous operation capabilities to ensure timely manure processing and stable fertilizer output.

Second, consider the characteristics of the raw materials. Farms primarily use livestock and poultry manure as their raw material, which is high in moisture and contains impurities such as crude fiber. Therefore, the equipment needs to have strong anti-clogging capabilities, and the roller surface should be made of a non-slip and wear-resistant material to prevent slippage and affect granulation efficiency.

Supporting facilities should be planned simultaneously. It’s recommended to use pre-treatment equipment such as dewatering machines and crushers to control the moisture content of raw materials within an appropriate range, and to configure screening devices to grade finished particles to improve fertilizer quality. Furthermore, consider equipment energy consumption, prioritizing energy-efficient models to reduce operating costs.

A balance should be struck between price and after-sales service. Avoid blindly pursuing low-priced equipment, as its materials and workmanship may be defective and increase maintenance costs. Choose a manufacturer that can provide installation and commissioning, operator training, and rapid fault response to ensure stable operation after the equipment is commissioned and minimize losses caused by downtime.

A comprehensive assessment of production scale, raw material characteristics, equipment quality, supporting capabilities, and after-sales service is crucial to selecting a double-roller press granulator suitable for your farm, ensuring efficient resource utilization of manure.

How to Process Compound Fertilizer Using a Rotary Drum Granulator

With the development of agriculture and technological advancements, market demand has become increasingly diversified. Rotary drum granulators have also attracted significant attention for their high efficiency, ease of operation, and excellent granulation results, making them a standout among other fertilizer granulators.

In the fertilizer production process, fertilizer granulators are crucial for determining fertilizer yield and quality. The quality of this equipment directly impacts the user’s economic benefits. During the rotary drum granulator production process, increasing the material temperature is necessary to improve the solubility of the granules. To reduce heat energy consumption during the drying process, the performance of the granulator must be effectively maintained.

To reduce production costs throughout the fertilizer production process, low energy consumption and high efficiency must be achieved at every stage of the granulation process. A high granulation rate in a rotary drum granulator ensures consistent production. To ensure this high granulation rate, the smoothness of the granulator’s inner wall must be enhanced. A smooth inner wall reduces friction, allowing the material to roll back and forth and quickly form granules. Our rotary drum granulator differs from traditional granulators. As the granulator’s lining rotates upward with the drum, it sags due to its own weight, allowing any material adhering to the lining to fall due to gravity, thus automatically removing lumps. Furthermore, this reduces the amount of water added during the granulation process, thereby alleviating the drying load during fertilizer processing.

In fertilizer production, large-scale rotary drum granulators can be equipped with two drum fertilizer screeners. The first is used to remove fines and small particles. The second drum fertilizer screener has two screen sections. One section, with a small mesh, selects particles that meet the requirements. These particles are then conveyed by a conveyor to the packaging machine. The other section, with a mesh, removes oversized particles, which are directly sent to a chain crusher for crushing before returning to the granulator.

Current Status and Development Trends of the Rotary Drum Granulator Market

As a key piece of equipment for powder granulation, the current market for rotary drum granulators exhibits distinct characteristics and clear trends.

Currently, market demand for rotary drum granulators is extremely strong. In the agricultural sector, with growing interest in green and environmentally friendly fertilizers, the production of organic and compound fertilizers is expanding, significantly driving demand for drum granulators. Many organic and compound fertilizer manufacturers are investing in advanced rotary drum granulators to improve production efficiency and ensure product quality. In addition to agriculture, industries such as chemicals and feed are also increasing their investment in drum granulators due to demand for granular products.

Market competition is becoming increasingly fierce. The influx of manufacturers has led to a complex product range and varying quality. Large companies dominate the market, leveraging their strengths in technological research and development, quality control, and after-sales service networks. Smaller companies rely on low prices to compete, but lag significantly behind in quality and innovation.

Technically, high-end equipment is becoming the mainstream. Models with automated control, intelligent monitoring, and high-efficiency energy-saving features are increasingly popular. They improve production efficiency and product quality while reducing labor and energy costs, meeting the demands of intelligent and green production.

Future development directions are clear: First,intelligent upgrades: equipment will enhance self-diagnosis and automatic adjustment capabilities, enabling parameter adaptation and unmanned production. Second,deepening energy conservation and environmental protection efforts: adopting advanced technologies and designs to reduce energy consumption and emissions, meeting stringent environmental requirements. Third,specialized segmentation: developing customized products for different industries, raw materials, and needs to meet individual market demands.

In short, the rotary drum granulator market presents both opportunities and challenges. Companies must focus on technological innovation, quality improvement, and service optimization to remain competitive.

The Important Role of Disc Granulators in Fertilizer Production Lines

In the granulation process of fertilizer production, disc granulators, with their unique structure and performance, are the preferred equipment for small and medium-sized production lines. Known as the “precision shaper” of fertilizer granules, their core advantage lies in efficiently converting powdery materials into regular granules, balancing production efficiency and product quality.

The simplicity of their structural design is a notable feature. The main body consists of an inclined disc, a transmission mechanism, and a frame. The disc’s inclination can be adjusted within a certain range, controlling the material’s residence time within the disc. This minimalist design not only reduces equipment failure rates but also facilitates routine maintenance. Compared to drum granulators, the disc granulator occupies nearly half the floor space, making it particularly suitable for production environments with limited space.

The wide range of compatible raw materials enhances its practical value. Disc granulators can be used for granulation in both organic fertilizer production lines and NPK compound fertilizer production lines. Their unique rolling granulation method reduces clumping of materials with high moisture content. For organic raw materials containing coarse fiber, they can also gradually agglomerate to form stable granules, eliminating the need for complex pretreatment. Energy and cost-effectiveness highlight competitive advantages. Compared to extrusion granulators, disc granulators consume less power and require no mold replacement, reducing equipment wear and maintenance costs. Furthermore, their stable continuous production capacity allows a single unit to meet the production needs of small and medium-sized fertilizer plants, helping companies reduce initial investment and operating costs.

Amid the development of green agriculture, disc granulators, with their high efficiency, flexibility, and cost-effectiveness, have become a crucial piece of equipment in the fertilizer forming process, providing strong support for improving fertilizer quality and promoting sustainable agricultural development.