The key factor in selecting a double screws compost turning machine is accurately matching your needs

fertilizer granulator Nov 15, 2025

For fertilizer companies, choosing the right double screws compost turning machine can increase fermentation production capacity by 30% while also reducing energy consumption and labor costs.

1. Compatibility with Fermentation Tank Specifications

The operating width of the double screws compost turning machine must match the width of the fermentation tank (common widths are 3-6 meters), and the turning depth must match the tank depth. If the tank is too wide or too deep, the edge materials may not be turned properly.

2. Matching Processing Capacity with Production Capacity

Select the equipment’s processing capacity based on the daily fermentation raw material volume (a single machine can process 50-200 tons per hour). Small and medium-sized companies can choose a small machine (50-100 tons/hour). Large-scale production lines require a large double screws compost turning machine, while also allowing for 10% redundancy to account for raw material fluctuations.

3. Adaptability to Raw Material Characteristics

When processing livestock and poultry manure with high moisture content, choose equipment with spiral blades equipped with an anti-stick coating to prevent entanglement. When processing straw-like fiber materials, prefer models with a wide spiral blade spacing (15-20cm) to enhance material throwing and reduce clogging.

4. Power and Energy Considerations

Preferably choose models with variable frequency motors, which can adjust the speed based on the moisture and viscosity of the raw material. Also consider the double screws compost turning machine’s travel system. Track-type models are suitable for fixed fermentation tanks, while crawler-type models are suitable for flexible adjustments to the fermentation area.

How should a windrow compost turner be adjusted for different organic fertilizer raw materials?

fertilizer granulator Nov 14, 2025

Organic fertilizer raw materials vary greatly, such as straw, chicken manure, mushroom residue, and distiller’s grains, and their properties can vary greatly. When using a windrow compost turner, a few adjustments can ensure smoother fermentation.

If you’re turning dry straw, it’s fluffy and porous, but it’s prone to “lifting.” The blades of a windrow compost turner tend to only scrape the surface, failing to thoroughly turn the bottom. In this case, you can steepen the blade angle to allow it to penetrate deeper into the pile. At the same time, slow down the compost turner’s speed to 2-3 kilometers per hour. This ensures that both the top and bottom of the straw pile are turned loosely, breaking up any large clumps and facilitating subsequent fermentation.

If you’re turning wet, sticky raw materials like chicken manure and pig manure, they tend to clump and stick to the blades, and the pile may become compacted after turning. At this time, the blade angle should be adjusted to a gentler angle to reduce sticking, and the forward speed can be increased slightly to allow the turned manure pile to quickly disperse and breathe. Additionally, before turning the pile, sprinkle some dry sawdust on the surface. This will automatically mix the material as the compost turner turns, reducing moisture and preventing clumping.

When turning fine ingredients like mushroom residue and distiller’s grains, the main concern is “missing” them. If the pile is too loose, they can easily leak through the gaps between the blades. By reducing the blade spacing on the windrow compost turner and maintaining a moderate speed, the fine ingredients can be turned over, ensuring even mixing and accelerating fermentation by about 10 days.

Key points for retrofitting organic fertilizer production lines under environmental compliance requirements

fertilizer granulator Nov 12, 2025

With increasingly stringent environmental protection policies, environmental retrofitting of organic fertilizer production lines has become an industry imperative, focusing on the treatment of “three wastes” and compliance upgrades.

For waste gas treatment, organic fertilizer production lines must be equipped with sealed fermentation chambers and ammonia collection systems. Biofilter technology is used to control ammonia concentrations generated during the fermentation process to within standards. Some areas also require VOC monitoring equipment to ensure real-time upload of emission data.

For wastewater treatment, production lines must establish a recycling system to sediment and filter wash water and condensate before reusing them for raw material moisture conditioning, achieving zero wastewater discharge.

For solid waste treatment, optimized screening processes are employed to re-crush fermentation residues before mixing them back into fermentation, achieving full solid waste utilization.

Furthermore, the environmental impact assessment process imposes stricter requirements on production line site selection and capacity planning, such as requiring them to be at least 500 meters away from residential areas and designing production capacity to match the regional environmental carrying capacity. Although these transformations increase initial investment (usually the transformation cost of a single production line accounts for about 15%-20% of the total investment), the energy consumption of the organic fertilizer production line can be reduced by 12%-18% after the transformation.

Key technology paths for low-energy retrofitting of NPK fertilizer production lines

fertilizer granulator Nov 11, 2025

To achieve the goal of efficient fertilizer production, low-energy retrofitting of NPK fertilizer production lines has become an industry imperative, with key improvements focused on optimizing technologies in high-energy-consuming processes.

In the raw material pretreatment stage, a waste heat recovery system is used to redirect 80-120°C exhaust gases generated during the drying process into the pulverization process, reducing energy consumption by 18%-22% and simultaneously reducing thermal emissions.

In the granulation process, a core energy consumer, traditional steam heating is gradually being replaced by electromagnetic heating, increasing heating speed by 50% and boosting thermal efficiency from 65% to over 90%. This reduces energy consumption per ton of product by approximately 80 kWh.

A closed-loop cooling system is introduced in the cooling process, increasing water reuse from 30% to 95% while minimizing the impact of circulating water on the surrounding environment.

In addition, the NPK fertilizer production line has achieved refined management and control through motor frequency conversion and an intelligent energy consumption monitoring platform. This platform monitors power changes across each device in real time, allowing for timely adjustment of operating parameters and avoiding idle energy consumption. Data shows that after systematic low-energy consumption upgrades, the NPK fertilizer production line can reduce overall energy consumption per ton of NPK fertilizer by 25%-30%, achieving both environmental and economic benefits.

Why do horizontal crushers require special adaptations for bio-fertilizer production?

fertilizer granulator Nov 10, 2025

The core difference between bio-fertilizer production and conventional organic fertilizer and compound fertilizer production lies in the need to preserve the activity of the inoculant. Furthermore, the raw materials often consist of specialized materials such as fungus residue, traditional Chinese medicine residue, and fermented straw. This places special demands on grinding equipment: low temperature, pollution prevention, and precise particle size. Through targeted modifications, horizontal crushers have become the ideal choice for bio-fertilizer production.

1.Low-temperature crushing preserves inoculant activity

The functional bacteria in bio-fertilizer (such as Bacillus subtilis and phosphate-solubilizing bacteria) are not tolerant to high temperatures. Excessive frictional heat (above 45℃) generated during the grinding process can inactivate the bacteria. High-quality horizontal crushers optimize the impeller speed (to avoid excessive friction) and some are equipped with a “water-cooling jacket” to circulate cold water to remove heat from the chamber walls, maximizing inoculant activity.

2.Anti-residue design prevents cross-contamination

Bio-fertilizer production often requires switching between different inoculant formulations. If residual material from previous batches remains in the equipment, bacterial strains can mix. The horizontal crusher’s “fully open cleaning structure” solves this problem. The grinding chamber door can be fully opened, and the smooth, corner-free interior allows for quick cleaning without disassembling core components, reducing the risk of cross-contamination.

3.Precise Particle Size for Microbial Agent Mixing

Bio-fertilizer production requires uniform particle size (typically 1-3mm) after grinding. Uneven particle size results in incomplete mixing of the microbial agent and raw material, impacting fertilizer efficiency. The horizontal crusher can precisely control particle size deviation within ±0.5mm, providing a high-quality raw material foundation for subsequent microbial agent inoculation and mixing.

Ring die pelleting machines: Why can they adapt to the different needs of organic and compound fertilizers?

fertilizer granulator Nov 7, 2025

In the fertilizer industry, the physical properties of organic fertilizers (mostly made from fermented manure and straw) and compound fertilizers (mostly made from phosphate rock, potassium chloride, and urea) differ significantly. Organic fertilizers are fibrous, highly moist, and prone to sticking together, while compound fertilizers are hard, fiberless, and require high-hardness molding. Ring die pelleting machines, through their “adjustable structure + material adaptability,” can meet the granulation needs of both fertilizer types.

For organic fertilizer granulation, ring die pelleting machines offer two key design advantages: First, they utilize a “low compression ratio” ring die (3:1-5:1) to avoid excessive compression that damages the organic matter and bacterial inoculant activity in the raw material, while ensuring that the granules do not break apart. Second, they feature an “anti-sticking die conditioning system” that precisely controls the amount of water added and a small amount of binder (such as starch residue) to reduce material sticking to the die, thereby improving molding efficiency and discharge speed.

For compound fertilizer granulation, the ring die pelleting machine focuses on “wear resistance and high extrusion capacity”: the ring die is made of wear-resistant alloy material, which can withstand the high-frequency friction of mineral raw materials and has a service life three times longer than that of ordinary materials; the pressure roller is hardened to enhance the extrusion force, and is equipped with a “high compression ratio ring die” (6:1-8:1) to ensure that the hardness of the compound fertilizer particles meets the standard.

Flat die pelleting machines: Why are they suitable for small and medium-sized organic fertilizer companies?

fertilizer granulator Nov 6, 2025

Small and medium-sized organic fertilizer companies are characterized by moderate production capacity, diverse raw materials, and large batch sizes. The design features of the flat die pelleting machine perfectly meet these needs, making it a cost-effective choice for these companies.

1.Low Equipment Investment Cost

The flat die pelleting machine has a relatively simple structure and does not require a complex transmission system. The purchase cost of a single unit is only 60%-70% of that of similar granulator equipment with similar production capacity. Furthermore, installation does not require a complex foundation, saving small and medium-sized companies from the high initial investment.

2.Flexible Raw Material Adaptability

Small and medium-sized organic fertilizer companies often purchase local raw materials, which can have large fluctuations in moisture and fiber content. The flat die granulator’s wide adaptability allows it to handle high-fiber straw materials, and the vertical compression of the rollers prevents tangling. For fermented materials with slightly higher moisture content, the flat die surface is easy to clean and prevents sticking.

3.Convenient Production Changeover

Small and medium-sized companies often produce a variety of products in small batches, requiring frequent adjustments to pellet size. It only takes 1-2 people to replace the flat die of the flat die pelleting machine, and it can be completed within 30 minutes. In addition, the cost of flat dies with different apertures is low. The company can reserve multiple sets of flat dies and quickly switch product specifications to meet the needs of different customer orders.

Drum fertilizer dryer: The logic of “Efficient Dehydration” for high-moisture fertilizers

fertilizer granulator Nov 5, 2025

In fertilizer production, high-moisture raw materials (such as fermented organic fertilizers and wet materials after compound fertilizer granulation) are prone to caking and mold if not dried promptly, affecting product quality and storage life. Drum fertilizer dryers, with their “continuous drying + uniform heating” characteristics, have become a core dehydration equipment in the fertilizer industry. Their operating principle is precisely adapted to the characteristics of fertilizer raw materials.

The core structure of a drum fertilizer dryer is an inclined rotating drum equipped with a heating system and a discharge device. During operation, high-moisture fertilizer (30%-50% moisture content) enters the drum through the high-end feed port. The motor drives the drum to slowly rotate, continuously turning the material and moving it forward. Simultaneously, the high-temperature hot air generated by the heating system fully contacts the material, rapidly removing moisture from the material through a dual heat transfer process of “convection and conduction.”

To prevent fertilizer clumping, a lifting plate is often installed inside the drum. This plate continuously lifts and drops the material, increasing the heating surface and ensuring uniform drying of each portion. The drum’s tilt angle is adjustable to control the material’s residence time within the drum, thereby precisely controlling the moisture content after drying. The entire process is continuous and stable, suitable for the mass production needs of organic fertilizer production lines. The dried material is loose and free of lumps, eliminating the need for secondary crushing.

Common troubleshooting and solutions for double screws compost turning machines

fertilizer granulator Nov 4, 2025

Double screws compost turning machines operate frequently in organic fertilizer fermentation workshops. Improper operation or untimely maintenance can easily lead to problems such as uneven turning, insufficient power, and equipment jamming, impacting fermentation progress.

1.Dead corners remain after turning, and some areas remain uncomposted

The main cause is excessive clearance between the spiral blades and the sidewalls of the fermentation tank (over 10 cm), or the double screws compost turning machine is moving too fast, preventing material from being turned over the edges. To address this, adjust the position of the spiral blades to reduce the clearance to within 5 cm. Also, reduce the double screws compost turning machine’s speed to ensure that every area is thoroughly turned.

2.Motor overload and tripping, insufficient power

This is often caused by excessive moisture content (over 70%) in the raw materials, resulting in increased friction on the spiral blades due to high viscosity, or by large impurities in the raw materials that may be blocking the blades. To address this, adjust the moisture content of the raw materials to 60%-65% before clearing impurities from the fermentation tank. If the compost tank is frequently overloaded, check the tightness of the motor belt and tighten or replace it.

3.Rapid wear of spiral blades, reducing turning capacity

This is primarily due to the presence of hard impurities (such as sand and gravel) in the raw materials, or the blade material not being suitable for wear resistance. To address this, install a screen to filter out hard particles before the raw materials arrive. Regularly inspect the blades for wear. If the blade thickness has decreased by 1/3 or cracks appear, replace them promptly.

Flat die pelleting machine: Protecting the activity of microbial agents in low-temperature granulation

fertilizer granulator Nov 3, 2025

The core challenge in biofertilizer production lies in ensuring that the granulation process does not destroy the activity of the microbial agent. Most functional bacteria (such as Bacillus subtilis and Trichoderma harzianum) are significantly inactivated at temperatures above 45°C. The flat die pelleting machine, with its low-temperature granulation capabilities, is a suitable choice for biofertilizer production. Its core advantage lies in its low-friction, no-additional-heat granulation process.

The flat die pelleting machine utilizes a vertical extrusion process, with the rollers and the die in contact with each other over a surface area rather than at points. This results in more uniform force per unit area, less frictional heat generation, and a temperature within the granulation chamber typically maintained at 35-40°C, well below the inactivation threshold of the microbial agent.

Furthermore, the machine does not rely on high-temperature conditioning or hot air conditioning; instead, it achieves granulation solely through the viscosity of the raw material and moderate extrusion, eliminating the need for additional heat input.

Furthermore, the flat die granulator’s speed is adjustable (typically 30-50 rpm). For biofertilizer raw materials with high microbial content, the speed can be reduced to below 30 rpm to further reduce frictional heat generation and ensure a microbial survival rate above 85%.

In practical applications, it is even more effective when used with a “room-temperature binder.” This eliminates the need for heating and dissolving the pellets, while also improving the pelletizing efficiency and complementing the flat die pelleting machine‘s low-temperature characteristics. This ensures the biofertilizer’s core function (microbial activity) while producing uniform pellets, meeting the dual requirements of “functionality” and “commerciality.”