Organic fertilizer raw material processing is a fundamental step in the organic fertilizer production line. It requires tailored processes tailored to the specific characteristics of the raw materials and specialized equipment to achieve harmless and resource-efficient conversion.
Classification and pretreatment are the primary steps and require the support of specialized equipment. Livestock and poultry manure must first be filtered through a vibrating screen to remove impurities such as sand, gravel, and plastic. It is then dehydrated to adjust the moisture content to approximately 60%. Excessively high moisture content can easily lead to anaerobic fermentation and produce foul odors, while too low a moisture content inhibits microbial activity. Straw raw materials must be pulverized to a particle size of 3-5 cm using a straw crusher. This increases the contact area with microorganisms and avoids uneven bulk density caused by excessively long straw.
Optimizing raw material blends requires the use of mixing equipment to improve efficiency. Using a single raw material often has drawbacks: pure manure has a low carbon-to-nitrogen ratio (approximately 10:1), which can easily lead to ammonia volatilization losses; pure straw has a high carbon-to-nitrogen ratio (approximately 80:1), resulting in a prolonged fermentation cycle. Using a double axis mixer to mix the materials in the right proportions can achieve a balanced carbon-nitrogen ratio. For example, a 3:1 ratio of chicken manure to corn stalks can adjust the carbon-nitrogen ratio to the ideal range of 25:1. Adding fluffy materials like sawdust and rice hulls can improve air permeability and prevent localized oxygen depletion in the pile. Incorporating wood ash can adjust the pH, creating a neutral to alkaline environment suitable for microorganisms.
Safety treatment is a key requirement. High-temperature fermentation is key to killing pathogens and parasite eggs. Regularly turning the pile to above 55°C and maintaining it for 5-7 days using a compost turning machine effectively inactivates harmful organisms. For raw materials containing excessive heavy metals (such as some industrial sludge), chemical passivation technology is required, using substances such as calcium carbonate and potassium dihydrogen phosphate to reduce the bioavailability of heavy metals. Furthermore, for livestock and poultry manure containing antibiotics, functional microbial agents can be introduced to accelerate degradation, ensuring that the finished product meets safety standards.
Scientific raw material processing combined with adaptive equipment can not only shorten the fermentation cycle, but also improve the nutrient content and safety of organic fertilizer, laying a good foundation for subsequent organic manure production.
