Organic fertilizers, made from organic waste materials through scientific processing, not only enable the resource utilization of waste but also improve soil quality and enhance crop yield. They combine environmental protection with agricultural value. The production of organic fertilizers is standardized and easy to understand, suitable for both large-scale mass production and small-scale workshop processing. The core lies in controlling the degree of decomposition and the ratio of raw materials.
Raw material pretreatment is the foundation of production, directly affecting the fertility and safety of the finished product. Organic raw materials such as livestock and poultry manure, straw, bamboo residue, and kitchen waste should be selected, along with auxiliary materials such as coal ash and plant ash to adjust texture and nutrients. Straw and bamboo residue should be crushed into short fibers of 1-1.5 mm, and coal ash should be ground into fine particles of 70-150 mesh. Kitchen waste needs to be pre-treated to remove oil, plastics, and other impurities and dewatered. The various raw materials are mixed in proportion, controlling the moisture content of wet materials such as livestock and poultry manure to 35%-45%, and adjusting the carbon-nitrogen ratio to 25-30:1. This ratio can significantly improve the efficiency of subsequent decomposition and prevent nutrient loss.
Fermentation and decomposition are the core steps and crucial for preventing organic fertilizer from burning seedlings. The mixed materials are piled in a ventilated or enclosed fermentation shed, inoculated with functional microbial agents such as straw decomposers and EM bacteria. Regular turning with a turning machine provides sufficient oxygen to the materials, promotes the activity of beneficial bacteria, and ensures even heating of the materials, preventing incomplete fermentation in some areas. During fermentation, the temperature should be controlled at 55-65℃, a temperature range that kills insect eggs, pathogens, and weed seeds. Fermentation continues for 7-15 days, during which temperature and humidity are monitored during turning with the compost turning machine, and water or additional materials are added as needed. When the material temperature drops below 40℃, there is no pungent odor, and the material turns dark brown, the decomposition is complete. After decomposition, porous aggregates can be added to enhance the stability of subsequent granulation and the slow-release properties of the fertilizer.
Granulation, drying, cooling, and screening are the key steps in shaping the final product. Using a new type organic fertilizer granulator or rotary drum granulator, the composted material is thoroughly mixed with aggregates to produce uniform granules of 4-5 mesh size. A small amount of binder can be added during granulation to improve granule hardness. This is followed by low-temperature drying, with the temperature controlled below 65℃, reducing the moisture content of the granules to below 8%. This ensures the granules' compressive strength while preventing high temperatures from damaging the functional microbial communities. After drying, the granules are cooled using a cooling machine to quickly reduce the temperature to near room temperature. This prevents secondary fermentation, clumping, or nutrient loss caused by direct stacking of hot granules, and also improves granule hardness, facilitating subsequent screening and storage. After cooling, oversized granules and fine powder are removed through screening. Oversized granules are crushed and returned for reprocessing, and fine powder is recycled, reducing raw material waste.
Finally, the qualified granules are packaged and stored in a dry and ventilated place to prevent moisture absorption and clumping. Following this process, organic fertilizer with sufficient fertility and stable properties can be produced. The organic fertilizer production process is both practical and environmentally friendly, suitable for various crops such as grains, fruits, and vegetables, contributing to the sustainable development of ecological agriculture.
