Cow manure, a common form of livestock waste, may seem like waste, but it is actually a high-quality raw material for making organic fertilizer. Converting cow manure into efficient organic fertilizer not only solves pollution from livestock farming but also provides natural nutrients for crops, achieving "turning waste into treasure." This process is not simply about piling it up; it requires scientific and standardized treatment, mainly consisting of four core steps.
The first step is raw material pretreatment. Fresh cow manure has a high water content and many impurities, making it prone to rotting and incomplete fermentation if fermented directly. It needs to be sun-dried or mechanically dehydrated to reduce the water content to 60%-70%, while simultaneously screening to remove impurities such as stones, weeds, and plastics. In addition, straw, sawdust, and other auxiliary materials can be added in proportion to adjust the carbon-to-nitrogen ratio, creating suitable conditions for microbial fermentation and preventing off-odors and nutrient loss during fermentation.
The second step is high-temperature fermentation, which is the crucial step in turning cow manure into organic fertilizer. The pre-treated cow manure is thoroughly mixed with auxiliary materials and piled into a fermentation pile 1-1.5 meters high. The ambient temperature is controlled at 55-65℃, which effectively kills pathogens, insect eggs, and weed seeds in the manure. During fermentation, the pile needs to be turned regularly using a compost turning machine to ensure ventilation and allow microorganisms to move evenly while expelling harmful gases produced during fermentation. The entire fermentation process takes approximately 15-25 days, until the pile is loose, has no obvious odor, and turns dark brown.
The fourth step is processing and shaping. The aged organic fertilizer is crushed and screened to remove large impurities. It can be processed into granules using a granulator, or it can remain as powder, depending on the requirements. The granulator is the core equipment for making granular organic fertilizer, extruding and shaping the crushed material into uniformly sized granules. After granulation, drying and cooling treatment is required: the moisture content of the granules is reduced to below 15% using drying equipment to prevent sticking and clumping during storage; then, the temperature of the granules is reduced to room temperature using cooling equipment to prevent high-temperature mold growth and improve granule stability. Whether in granular or powder form, all organic fertilizers must undergo testing to ensure that their organic matter content, pH, and other indicators meet national standards before they can be used in agricultural production.
From cow dung to organic fertilizer, every step requires scientific management. This process not only achieves the resource utilization of waste but also provides high-quality fertilizer for green agriculture, possessing both environmental and economic value.
