Oxygen traces impact on biological methanation from hydrogen and CO.

Biomethane production from biological methanation of CO is promising both for biogas upgrading and surplus renewable energy storage. One of the questions for process upscaling is the impact of oxygen (in the biogas or in the purified CO-rich off-gas) on the biological process. An adapted anaerobic thermophilic consortium was submitted to increasing amounts of oxygen in batch and continuous tests at partial pressures ranging from 0 to 50 mbar.

Methods for the Evaluation of Industrial Mechanical Pretreatments before Anaerobic Digesters.

Different methods were tested to evaluate the performance of a pretreatment before anaerobic digestion. Besides conventional biochemical parameters, such as the biochemical methane potential (BMP), the methane production rate, or the extent of solubilization of organic compounds, methods for physical characterization were also developed in the present work. Criteria, such as the particle size distribution, the water retention capacity, and the rheological properties, were thus measured.

An improved procedure to assess the organic biodegradability and the biomethane potential of organic wastes for anaerobic digestion.

In this study a fractionation procedure was developed and applied to evaluate the potential of some organic wastes (two cattle manures and two catch crops, fresh and after ensiling) for anaerobic digestion. This procedure was based on water extraction of the raw sample, which enabled the evaluation of the contributions of water-soluble and particulate phases to the investigated properties. Biomethane potential (BMP) and chemical oxygen demand (COD) were determined and used to assess the anaerobic biodegradability of raw materials.