Harmless treatment Technology of Cow manure

Cow dung contains 14.5% organic matter, 0.30% Mel 0.45% nitrogen, 0.15% Mel 0.25% phosphorus, 0.10% Mel 0.15% potassium, and is a valuable resource that can be used as a source of soil fertilizer by the planting industry. The organic matter and nutrient content of cow manure is the lowest among all kinds of livestock, with fine texture, more water content, slow decomposition and low calorific value, so it belongs to late-acting fertilizer.

? 1. Composting. Composting technology is an important way for harmless treatment and resource utilization of cow manure. Cow manure composting was systematically studied in the aspects of matching fermentation with other resources, optimization of fermentation bacteria, additives, fermentation temperature, humidity, characteristics of fermented products and so on.

? 2. Earthworms compost. The use of earthworms to treat livestock and poultry waste is an ancient and new biotechnology. Since the late 1980s, many scholars at home and abroad have devoted themselves to the study of using earthworms to treat waste. Compared with the mature cow manure produced by natural composting, the mineral nitrogen and available potassium of earthworm compost were higher than those of mature cow manure, but there was no significant difference in available phosphorus, and the microbial biomass carbon and nitrogen and enzyme activity were significantly higher than those of natural mature cow dung. The number of bacteria, fungi and actinomycetes was also higher than that of natural mature cow manure, but fluctuated greatly.

? 3. Catalytic oxidation treatment. Cow dung was degraded by catalytic oxidation to transform undigested crude fiber, crude protein, crude fat and humic acid into water-soluble organic matter and amino acid fulvic acid (A-FA). The reaction is carried out under fully closed conditions, and there is no discharge of waste gas, waste liquid and waste residue in the whole process. The composition of water-soluble organic matter in the product includes fulvic acid, amino acids, other low molecular organic acids and sugars. The content of carboxyl, phenolic hydroxyl and other active functional groups is slightly higher than that of weathered coal and peat fulvic acid, close to soil fulvic acid, and the product has high chemical activity and biological activity.

? 4. Used in aquaculture. Because the feed is highly degraded by microorganisms in cattle, the oxygen consumption of cow manure is lower than that of other livestock and poultry manure. Practice has proved that the phenomenon of anoxic floating head in fish ponds is less when cow dung is applied in fish ponds. Cow dung does not need fermentation when raising fish, it is better to use fresh manure. The number and quantity of release should be flexibly controlled according to the weather, water color, fish growth and floating head. Table 1 shows the proportion and frequency of cow dung applied in fish ponds in southern Jiangsu. Zhang Zhibin