What is the production process of bio-organic fertilizer granules?

Bio-organic fertilizer granules have become a mainstream choice in modern agriculture due to their advantages such as easy storage and transportation, balanced fertilizer effect, and convenient application. Their production process relies on a bio-organic fertilizer production line and is a precise, interconnected process that must both preserve the activity of beneficial microorganisms and create a stable granule shape. It can be divided into four key stages.

Raw material pretreatment is the foundation of granule production. First, organic raw materials such as livestock and poultry manure, straw, and mushroom residue are processed to a fineness of 20-40 mesh using crushing equipment to ensure uniform mixing. Then, at a carbon-to-nitrogen ratio of 25-30:1, auxiliary materials are added using a mixer to adjust the moisture content to 55%-60%, creating a suitable environment for microbial fermentation. This step requires strict control of the impurity content of the raw materials to avoid hard objects such as gravel and metal affecting the operation of subsequent bio-organic fertilizer equipment.

The core fermentation stage is the source of the "activity" of the granular fertilizer. The pre-treated material is fed into fermentation tanks or windrow fermentation fields, where it is periodically turned and aerated using a turning machine, maintaining a temperature of 55-65℃ for 7-10 days to achieve harmless treatment and composting. During the later stages of fermentation, functional microbial agents are introduced, followed by low-temperature aging for 3-5 days to ensure that each gram of fertilizer contains ≥200 million effective live bacteria—a key indicator distinguishing it from ordinary organic fertilizers.

Deep processing and shaping determine granule quality. The composted material is then finely ground a second time to at least 60 mesh before entering a granulator (commonly a disc granulator or extrusion granulator), where it is rolled into uniform granules of 2-5mm at a suitable humidity (40%-45%). The shaped granules are then immediately sent to a dryer, where they are dried at a low temperature below 60℃ until the moisture content is ≤15%, ensuring granule strength while preventing the high temperature from killing beneficial bacteria. After drying, the granules are graded by a screening machine, with substandard granules returned to the grinding stage for re-granulation.

Post-processing and quality inspection are essential guarantees before the product leaves the factory. Qualified granules are cooled to room temperature by a cooler to reduce the risk of moisture absorption and clumping. Finally, they are automatically packaged in 25kg or 50kg packages. Simultaneously, samples are taken for testing of viable bacteria count, organic matter content, pH value, and other indicators to ensure compliance with the national standard. The entire process requires complete control of dust and odor, and is equipped with environmental protection equipment to achieve green production.

This process not only considers the resource utilization of organic materials but also achieves a unity of "activity" and "form" through precise process control, providing reliable fertilizer support for improving agricultural quality and efficiency.