In BB fertilizer (blended fertilizer) production, the BB fertilizer mixer is a key piece of equipment that determines product quality. Its core function is to evenly blend multiple raw materials of varying density and particle size into a nutrient-consistent fertilizer, directly impacting subsequent fertilization effectiveness.

In terms of equipment structure, mainstream BB fertilizer mixers mostly adopt a closed-cylinder design with an internal mixing assembly. The cylinder is typically positioned horizontally, with the mixing assembly driven by a motor. Some BB fertilizer mixers also feature forward and reverse rotation to reduce residual material in the cylinder. The feed inlet is typically located at the top of the cylinder, and the discharge outlet at the bottom. Some models feature an observation window for easily monitoring the mixing status.

During operation, raw materials such as urea, monoammonium phosphate, and potassium chloride are introduced into the mixing cylinder according to the formulated ratio. The rotating mixing assembly propels the raw materials: the screw conveys the raw materials from both ends toward the center, the paddles shear and stir the raw materials, and the guide plates facilitate convection, ensuring full contact between raw materials with density differences of 30%-50%. The entire process does not require the addition of adhesives, and mechanical force is used to achieve “small particles filling gaps and large particles colliding with each other”, ultimately achieving a uniform mixing effect.

As the fertilizer industry upgrades toward “precision and functionalization,” demand for functional fertilizers such as slow-release fertilizers, biofertilizers, and trace element compound fertilizers has surged. The production of these fertilizers places special demands on granulators, balancing functional retention and granule formation.

For slow-release fertilizer production, fertilizer granulators must meet the dual requirements of “granule formation” and subsequent coating. For example, when producing sulfur-coated slow-release fertilizers, the granulation process requires producing base granules with a smooth surface and uniform hardness. The “rolling forming” feature of a rotary drum granulator is perfectly suited for this purpose. By controlling the drum speed (8-12 rpm) and the amount of binder used, the granules are naturally rounded and smooth. Some granulators also feature a “pre-cooling section” at the discharge port to reduce the granule temperature to below 30°C, paving the way for subsequent coating and preventing the coating material from melting and becoming ineffective due to high temperatures.

For compound fertilizers containing trace elements, fertilizer granulators must address the issue of uneven trace element distribution. These fertilizers contain low concentrations of trace elements such as zinc, boron, and iron. Inhomogeneous mixing can lead to nutrient deficiencies in some granules. In this case, the low-speed extrusion design of a flat die granulator is optimal. After thoroughly mixing the trace elements with the base raw materials in a twin-shaft premixer, the low-speed rollers slowly extrude the granules into shape, minimizing material separation and ensuring a trace element content variation of ≤0.1% per granule, thus preventing functional deficiencies.

For biofertilizers, the granulator’s low-temperature performance is crucial. Flat die and disc granulators utilize a low-friction, no-high-temperature extrusion design to maintain a temperature within the granulation chamber below 40°C, ensuring the survival rate of the microbial inoculant.

With the agriculture and fertilizer industries deeply intertwined, fertilizer form directly impacts fertilization effectiveness and industry efficiency. As the core equipment connecting fertilizer raw materials and finished products, fertilizer granulators are becoming a key driver of industry upgrades.

Fertilizer granulators transform powdered raw materials into uniform fertilizer granules through processes such as physical extrusion and conditioning. These granulated fertilizers are not only highly stable, making them suitable for long-term storage and long-distance transportation, but also enable a slow release of nutrients, extending the fertilizer’s effective lifespan and enabling more efficient crop absorption, thereby boosting agricultural production returns from the source.

Furthermore, the adaptability of fertilizer granulators meets the diverse needs of the industry. Whether producing organic fertilizers, compound fertilizers, or customized fertilizers for specific crops, the equipment can adapt to different raw material ratios by adjusting parameters. More importantly, modern fertilizer granulators continuously optimize energy efficiency, improving production efficiency while reducing energy consumption.

For fertilizer companies, fertilizer granulators are a powerful tool for enhancing product competitiveness. Against the backdrop of growing demand for high-efficiency fertilizers in agriculture, fertilizer granulators will undoubtedly drive fertilizer production towards greater efficiency, higher quality, and greater environmental protection.