Digestate management practices in Latvia from nitrogen perspective

Abstract Biogas is a common source of renewable energy. But biogas plants also produce a by-product which is at least as valuable as renewable energy, because of its nutrients and organic matter content – digestate. Digestate is an excellent fertilizer containing many different nutrients and micronutrients necessary for agriculture, including nitrogen, phosphorus and potassium. Digestate can be characterized based on the feedstock used to produce biogas. Latvia’s biogas plants produce digestate from: manure and agricultural sludge (85 %), sewage sludge (5 %) and municipal waste (10 %). However, digestate misuse can cause a serious threat to the environment. This study gathered information and proposes recommendations on the use of digestate in Latvia from nutrient perspective.