Cow manure, a common type of livestock manure, is rich in nutrients such as nitrogen, phosphorus, and potassium. However, applying it directly without sufficient fermentation can burn roots and seedlings and may spread pests and diseases. To achieve efficient and thorough fermentation of cow manure, scientific methods are needed, taking into account raw material ratios, environmental control, and operational details. This transforms "waste" into high-quality organic fertilizer, a crucial step in the organic fertilizer making process.
Raw material ratio is fundamental to successful fermentation. Cow manure has a fine texture and high moisture content, making it prone to poor aeration and slow temperature rise when fermented alone. It is recommended to mix cow manure at a ratio of 70%-80% cow manure + 20%-30% straw/sawdust.
The loose materials like straw and sawdust increase aeration and adjust the carbon-to-nitrogen ratio to the optimal range of 25:1-30:1, providing sufficient energy for microbial activity. If the cow dung has excessive moisture (drips water when squeezed into a clump), add a suitable amount of dry soil or wood ash to absorb the water, controlling the moisture content to 55%-60%, i.e., a consistency where it "can be squeezed into a clump but crumbles easily when released."
Environmental control determines fermentation efficiency. Microbial fermentation requires suitable temperature and ventilation. The fermentation pile should be located in a sunny, elevated area, avoiding water accumulation. The pile size should ideally be 2-3 meters wide and 1.2-1.5 meters high; too small and heat dissipation is easy, too large and internal ventilation is poor. In the early stages of fermentation, microbial activity will gradually raise the pile temperature. Maintain the pile temperature between 55℃ and 65℃; this temperature kills pathogens and insect eggs. When the pile temperature exceeds 65℃, turn the pile promptly to aerate it and prevent high temperatures from inhibiting microbial activity. If the pile temperature is below 50℃, add a small amount of urea to adjust the carbon-to-nitrogen ratio, or cover it with a thin film for insulation.
Standardized operation ensures thorough decomposition. When composting, the material must be compacted in layers to ensure close contact, while also leaving ventilation holes. During fermentation, the pile is typically turned 2-3 times. The first turning occurs after the peak temperature (approximately 7-10 days), followed by turning every 5-7 days thereafter. During turning, the unfermented outer layer is moved to the interior to ensure even decomposition. Under normal circumstances, fermentation is complete in 25-30 days. The matured cow manure is dark brown, odorless, and has a loose texture.For large-scale production, the fermented cow manure can enter the organic fertilizer production line, where it undergoes crushing, mixing, granulation, drying, and other processes, becoming part of the complete organic fertilizer production process, and finally being made into commercial organic fertilizer that is easy to store, transport, and apply. On a small scale, the decomposed cow manure can also be used directly for farmland fertilization, flower planting, and so on.
By scientifically controlling the three core aspects of raw materials, environment, and operation, cow manure fermentation can be made more efficient and more thorough. This not only solves the problem of livestock waste disposal but also provides high-quality raw materials for organic fertilizer production, resulting in green and environmentally friendly organic fertilizer and achieving a win-win situation for both ecological and economic benefits.
