Delivery of peel residues at Solrød Biogas 3.5.2 Technology description The use of dried peel for production of pectin and use of peel residues can been described as two steps in a cascade, both processes utilising residues as their raw material. The manufacturing of pectin from the dried peel happens in a step by step process. The first step is washing of the dried peel in hot water together with a dilute mineral acid. The solid and liquids are afterward separated as effectively as possible through a repeated filtration where suspended cellulose pulp is added to help the process. The solid peel residues are finally pressed and stored until transported to Solrød Biogas. The clarified extract afterward undergoes a concentration and precipitation process before the final drying, milling and blending process takes place. The peel residues are transported to Solrød Biogas by lorries where they are used as one of several feedstocks for the biogas production. Solrød Biogas has a treatment capacity of 200.000 tons per year. The biogas produced is used for CHP generation in a large gas engine. The power produced is sold to the grid and the heat is supplied to the local district heating system operated by Vestegnens Kraftvarmeselskab I/S (VEKS) that is owned by 12 municipalities in the Region Zealand and Capital Region. The digestate from the process is used as fertiliser for local farmers.
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