Publisher © Czech Geological Survey, ISSN: 2336-5757 (online), 0514-8057 (print)

Mineral phase in the digestate from the biogas power plants


Milan Geršl, Pavol Findura, Jan Mareček, Dalibor Matýsek, Tomáš Vítěz, Eva Geršlová

Geoscience Research Reports 47, 2014 (GRR for 2013), pages 110–111

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The biogas is produced from maize silage, grass silage, beef and pig manure and slurry, sewage sludge, organic wastes from food industries, organic household waste. As the main result the digestate (anaerobic digestion residues) is manufactured. The digestate is used as fertilizer and/or fuel. The digestate mineral composition was analyzed on samples from 7 agricultural biogas plants, and from university testing biogas reactor. Maize silage, beef and pig manure and slurry were examined as input substrates. The mineral composition was determined by x-ray diffraction with internal standard ZnO, evaluated according to Rietveld methods. The main components in the digeste present are in amorphous phase (77.5-98.7 wt. %), sylvite (1.2-4.1 wt. %), calcite, Mg-calcite (1.05-5.7 wt. %), and opal-CT (1.26-12.1 wt. %). The opal-CT in the studied samples originates from the SiO2 crystallization in technology. In the digestate were identified following minerals from agricultural soils: quartz 0.22-11.94 wt. %, albite 2.15-2.92 wt. %, orthoclase 0.86-2.31 wt. %, muscovite max. 3.60 wt. %, hornblende max. 0.12 wt. %.


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