Biogödsel

Biogödsel, or digestate, is a nutrient-rich by-product of anaerobic digestion of organic matter. It is used as a fertilizer and soil conditioner in agriculture, returning nutrients and organic matter to the soil.

Digestate is produced in anaerobic digesters where feedstocks such as livestock manure, slurry, crop residues, and food waste are broken down by microorganisms in oxygen-free conditions. The digestion process produces biogas, a fuel mainly of methane and carbon dioxide, and a residual digestate. After digestion, digestate is often separated into solid and liquid fractions, which can be applied separately depending on farming needs and management practices.

The composition of digestate includes plant nutrients—mainly nitrogen, phosphorus, and potassium—along with organic matter and micronutrients. Nutrient levels vary with the feedstock and digestion conditions. The digestion process reduces pathogens and odors, though certain pathogens may persist if temperatures are insufficient; post-treatment or proper storage can further mitigate risks.

Digestate can be used on agricultural land as a substitute or supplement for chemical fertilizers and as a soil conditioner. The solid fraction tends to improve soil structure and organic matter content, while the liquid fraction provides nutrients more readily available to plants. Application rates are determined by crop requirements, soil properties, and regulatory guidelines, with attention to preventing nutrient leaching and environmental impact.

From an environmental perspective, biogödsel supports nutrient recycling and reduces reliance on mineral fertilizers, while the anaerobic digestion process captures methane that would otherwise be released, contributing to greenhouse gas mitigation when managed responsibly and in conjunction with appropriate controls on contaminants.