The possibility of utilizing crude glycerol, a residue from biodiesel production, for biogas production is tested. For this purpose a multistage anaerobic digestor with semi-continuous feed of substrate is used. It was observed that the microbial pre-treatment and methanogenesis could be distributed in a series of compartments maintaining pH values suitable for methanogenic activity. Very high methane content (95% vol.) is detected in the biogas. When the digester is overloaded by substrate, pH drops because of acid accumulation. In this case the methane production ceases. This problem could be overcome by selective extraction of the accumulated carboxylic acids. The anaerobic digestion of glycerol may serve both for energy production by methane and for formation of value-added products like propionic acid and 2,3-butanediol.