In the current era of green agricultural development, organic fertilizer has become a crucial support for modern agriculture due to its advantages in improving soil, enhancing crop quality, and reducing pollution. Its production uses various organic wastes as raw materials, which are scientifically composted and processed to "turn waste into treasure," solving the problem of waste pollution while replenishing the soil with natural nutrients. Behind this lies a standardized set of raw material selection and production processes.
The raw materials for organic fertilizer production are widely available, but can be broadly categorized into four main types, balancing environmental friendliness and nutrient content. Livestock and poultry manure is the most basic raw material, including chicken, pig, and cow manure, rich in nitrogen, phosphorus, and potassium nutrients. Chicken manure, in particular, has a nitrogen content as high as 1.6%, but salt and odor issues need to be addressed. Agricultural and forestry waste, such as corn stalks, wheat straw, and sawdust, is rich in carbon and is mainly used to adjust the carbon-nitrogen ratio of the raw materials and improve fermentation permeability. Processing by-products, including distiller's grains, mushroom residue, and soybean cake, are rich in nutrients and can increase the added value of organic fertilizer. Soybean cake, in particular, can have an organic matter content of over 50%. In addition, green manure and kitchen waste, after processing, can also be used as supplementary raw materials to achieve resource recycling. All raw materials must meet national standards to ensure they are free of heavy metals, antibiotics, and other contaminants.
The production process of organic fertilizer mainly consists of four key stages, each directly affecting product quality. The first step is raw material pretreatment, where coarse fiber raw materials such as straw are crushed to 2-5 cm, and the moisture content of livestock and poultry manure is adjusted to 55%-65%. Various raw materials are then mixed in proportion, maintaining a carbon-to-nitrogen ratio of 25-30:1 to lay the foundation for fermentation. The second step is core fermentation, using aerobic composting technology. The mixed raw materials are piled into a 1.2-1.8 meter high heap, and oxygen is replenished by periodically turning the heap using a compost turning machine. The heap temperature is controlled at 55-65℃ and maintained for 5-7 days to thoroughly kill pathogens and insect eggs. The entire fermentation cycle takes approximately 15-30 days.
The third step is post-processing. After fermentation and decomposition, the material is sieved to remove impurities, and then crushed, granulated, dried, and cooled according to requirements to produce powdered or granular products, improving ease of use. The fourth step is finished product storage and testing. Qualified products are stored in a dry, well-ventilated place to prevent moisture absorption and clumping. Simultaneously, indicators such as organic matter, nitrogen, phosphorus, and potassium are tested to ensure compliance with NY525-2012 standards. Only products with a roundworm egg mortality rate of ≥95% and adequate fecal coliform counts can be released to the market.
A scientific raw material selection and organic fertilizer production process is key to the effectiveness of organic fertilizer. It not only realizes the resource utilization of organic waste but also promotes agricultural ecological cycles, providing strong protection for soil health and agricultural product safety, and contributing to sustainable agricultural development.
