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Updated: Aug 19, 2026
Measuring Biomethane Potential of Food Scrap Waste Anaerobically Co-Digested with Waste-Activated Sludge Using Respirometry
Published on: April 26, 2024
Respirometric assays at fixed and process temperatures to monitor composting process
Raquel Barrena Gómez1, Felícitas Vázquez Lima, Ma Angels Gordillo Bolasell
1Escola Universitaria Politécnica del Medi Ambient, Universitat Autónoma de Barcelona, Rambla Pompeu Fabra 1, 08100 Mollet del Vallès (Barcelona), Spain.
Abstract:
A static respirometer was built to determine the respiration index (RI) of composting samples. Respiration indices of different sludges were determined at 37 degrees C (RI37) and at the in situ temperature of the composter at sampling (RI(T)). Results indicated that both indices correlated well with temperature evolution in the composter. RI(T) were more representative of the metabolic activity in the reactor and more sensitive to temperature and composition variations of the composting material, but could not indicate the stability of the material at later stages of the process. Moreover, significance of RI units was shown in the composting of a highly compostable residue. According to the stability limits suggested in the literature, initial RI expressed on dry matter (DM) basis corresponds to a stable material (RI < 1 mgO2gDM(-1)h(-1)) whereas initial RI expressed on organic matter basis (OM) corresponds to an unstable material (RI = 2.5 mgO2gOM(-1)h(-1)).
