BASIC DATA ON BIOGAS - Energikontor Sydost

DigestateSwedish Gas Centre: Basic Data on BiogasBoth biogas and digestate are produced during anaerobic digestion. Thedigestate contains most of the nutrients originating from the substrate. Inorder to reach maximum recovery, these nutrients should be used asfertilizer for the production of new biomass.Depending on the substrate, the digestate has different properties. InSweden, the main substrates are sludge from wastewater treatment plantsand various food and industrial wastes such as food waste and slaughterhouse waste.REVAQ is a certification system for digestate from wastewater treatmentplants that are spread on arable land. The certification include an activeupstream work and continued improvements on the wastewater treatmentplant. Furthermore, the producer of the digestate has to be open with allinformation and has a developed traceability for the produced digestate. Inthe beginning of 2012, 45% of digestate from wastewater treatment plantswere certified according to REVAQ.The certification system “Certifierad återvinning” was initiated in 1999. Thecertification is voluntary and is based on open communication between theproducer and the consumer of the digestate through documentation andfree insight on the quality of the product. The entire chain from substrate toend product is adapted to environmental and user needs. The certificationof digestate from waste is described in SPCR120. Of the certified digestateaccording to SPCR120, 92% was spread on arable land in 2010.Certification symbols for ”Certifierad Återvinning” and REVAQ.16