In modern production of organic fertilizer, organic wastes are inoculated with microbial inoculants and processed into organic fertilizer according to the organic fertilizer production line. Owing to the use of aerobic fermentation method, organic fertilizer has a high level of harmlessness and nutrition. In organic fertilizer production, there are some key treatments that affect the quality of organic fertilizer.
The quality of organic fertilizer is closely related to the carbon-nitrogen ratio, fineness, moisture content and pH value of organic wastes. Several key technologies for producing organic fertilizer by high temperature fermentation of aerobic microorganisms and the influence of these factors are introduced here.
1. Matching of organic fertilizer raw materials, C/N ratio of organic fertilizer fermentation. Plant organic wastes, such as crop straw, contain more carbon and less nitrogen, so the ratio of carbon to nitrogen is high. If chicken manure and straw are properly matched, the carbon-nitrogen ratio of the mixture can be adjusted to 20-25:1. If the C/N ratio is too high, the decomposition rate of organic matter is slow, the fermentation time is long, and the humification coefficient is low, the product will easily cause soil nitrogen deficiency, thus affecting the growth and development of crops; if the C/N ratio is too low, the fermentation temperature will rise slowly, and the loss of organic nitrogen will be large. Therefore, adjusting the C/N ratio of the mixture can not only improve the quality of organic fertilizer produced by fermentation, but also affect the effect of application, which plays a great role. When we control the parameters of organic fertilizer production, we can calculate the C/N ratio of different kinds of organic wastes, determine the proportion of mixtures, adjust the C/N ratio of mixtures, and lay a foundation for the production of high quality organic fertilizer.
2. Control the moisture content of organic fertilizer fermentation materials. The water content of fermentation material is the key factor of organic fertilizer fermentation. Generally, the best moisture content of fermentation material is 60%-65%. In actual production, the wet material can be held by hand to form a mass. It is just right when there are droplets between fingers without dropping.
3. Fermentation and flipping of organic manure. The purpose of turning over is to remove carbon dioxide gas from the fermentation reactor, increase oxygen entering the air and keep fermentation going. The common dump equipment is trough compost turner and windrow compost turning machine. Mechanized turning of turning equipment is helpful for homogeneous fermentation and mixing of materials. Usually, the turning equipment is turned over twice in two days, but if the temperature is above 50 ℃ or above, whether or not the interval time of dump is reached, the turn over should be carried out immediately to keep the compost fermented normally.
Fermentation technology of organic fertilizer production is a biological treatment method which integrates harmless treatment and resource recycling. It is a significant improvement and innovation of traditional organic fertilizer production technology. Fermented organic fertilizer can be used as raw material for commercial organic fertilizer granulation.