Method for determination of methane potentials of solid organic waste

• Published in: Waste management (Elmsford) Vol. 24; no. 4; pp. 393 - 400
• Main Authors: Hansen, Trine L., Schmidt, Jens Ejbye, Angelidaki, Irini, Marca, Emilia, Jansen, Jes la Cour, Mosbæk, Hans, Christensen, Thomas H.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.01.2004; New York, NY Elsevier Science
• Subjects: Applied sciences; Biogas; Bioreactors; CELLULOSE; Characterization; Chemical Engineering; Civil Engineering; Engineering and Technology; Environmental Engineering; Environmental Monitoring - methods; ENVIRONMENTAL SCIENCES; Exact sciences and technology; Forecasting; Gases - analysis; GLUCOSE; Kemiteknik; Laboratory measurement; METHANE; Methane - analysis; Naturresursteknik; OILS; Organic Chemicals; Organic waste; ORGANIC WASTES; Pollution; PROTEINS; QUALITY CONTROL; Refuse Disposal - methods; Samhällsbyggnadsteknik; SENSITIVITY; SOLID WASTES; STARCH; Teknik; Temperature; Vattenteknik; Water Engineering; Methane; Characterization; Organic waste; Biogas; Laboratory measurement
• ISSN: 0956-053X; 1879-2456; 1879-2456
• DOI: 10.1016/j.wasman.2003.09.009

A laboratory procedure is described for measuring methane potentials of organic solid waste. Triplicate reactors with 10 grams of volatile solids were incubated at 55 °C with 400 ml of inoculum from a thermophilic biogas plant and the methane production was followed over a 50-day period by regular measurements of methane on a gas chromatograph. The procedure involves blanks as well as cellulose controls. Methane potentials have been measured for source-separated organic household waste and for individual waste materials. The procedure has been evaluated regarding practicality, workload, detection limit, repeatability and reproducibility as well as quality control procedures. For the source-separated organic household waste a methane potential of 495 ml CH 4/g VS was found. For fat and oil a lag-phase of several days was seen. The protein sample was clearly inhibited and the maximal methane potential was therefore not achieved. For paper bags, starch and glucose 63, 84 and 94% of the theoretical methane potential was achieved respectively. A detection limit of 72.5 ml CH 4/g VS was calculated from the results. This is acceptable, since the methane potential of the tested waste materials was in the range of 200–500 ml CH 4/g VS. The determination of methane potentials is a biological method subject to relatively large variation due to the use of non-standardized inoculum and waste heterogeneity. Therefore, procedures for addressing repeatability and reproducibility are suggested.