[Characteristics of the methane fermentation of waste of animal husbandry complexes with respect to the biomass of microorganisms and volatile fatty acids].

The content of microbial biomass and the concentration of volatile fatty acids were comparatively studied in the tanks where the waste products of three stock farms were subjected to methane fermentation. The biomass content was shown to vary from 19 to 30% of the dry matter weight and the concentration of volatile fatty acids from 0 to 4.5 g per litre. The low concentrations of acetic and propionic acids together with the high biomass content were indicative of an active balanced microbial association. The parameters can be used to assess the operation of methane fermentation tanks.