Gasification transforming organic compounds into energy-rich pyrolytic gas, is a climate-friendly treatment option for biological solid wastes. The condensates arising from the pyrolytic gas valorization is owing to high concentrations of small molecular phenols, cyanides, nitrogen-heterocyclics, aromatics and ammonium, posing an environmental and health hazard. In this paper, the watery phase of the biomass gasification condensate from spent mushroom compost (SMC), with a chemical oxygen demand (COD) of 16.4 g/L and total nitrogen of 2.3 g/L, was pretreated by Fenton oxidation. The experiments were conducted at room temperature with an initial pH value of 3, 5 and 8.9, hydrogen peroxide (H2O2) dosages between 15 and 100% of the normalized stoichiometric ratio (NSR), and Fe2+ dosages corresponding to molar ratio of H2O2:Fe2+ between 10 and 30. Through respiration inhibition assays, the best operational condition for detoxification was determined at an initial pH 5 with 30% NSR H2O2 dosage and molar ratio of H2O2:Fe2+ at 15:1. The specific operational cost of the Fenton oxidation was calculated at 2.17 €/kg CODelimination. In respiration inhibition assay, the oxygen consumption of wastewater after Fenton oxidation was increased by 316% in three days. In a 20 days’ biogas production test, the biogas production was increased by 81%.

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Bei der Biomassevergasung entstehen toxische Kondensate, wobei einige der entstehenden organischen Verbindungen als industrielle Plattformchemikalien gelten. Im Projekt ConPur wurden verschiedene Aufbereitungsverfahren erprobt.

Anaerobic digestion for biomethane production is an important tool regarding sustainable energy production. The objective of this study was to investigate the effects of the substrate composition and operating parameters on biomethane production during anaerobic digestion, focusing on the use of flotates and slaughterhouse waste as substrates with a high organic content. A novelty here was the use of a moving bed biofilm reactor (MBBR) with circulation pump for the anaerobic treatment of flotates, slaughter waste (SW), and their mixture. Flotates and waste from slaughterhouses offer a substrate with a high organic content. In this work, it was shown that both substrates provide a high biochemical methane potential (BMP). The highest methane yield was achieved by mixing both substrates. In continuous operation, special challenges arose, due to the high nitrogen and fat content of the substrates. These could be overcome by mixing the substrates and using a circulation pump in the reactor for improved back-mixing. As a result, the highest average methane yield of 0.65 NLCH4·gTS eli−1 was achieved in mesophilic operation at an organic loading rate (OLR) of 4.2 gTS·L−1·d−1.