Influence of different biomass treatment technologies on efficiency of biogas production.

The results of the influence of fresh grass, hay and silage of reed canary grass ( Phalaris arundinacea L.) on the efficiency of anaerobic digestion are presented in the paper. The environmental assessment of biogas production technology has been analysed in terms of life cycle assessment methodology as well. Energetic evaluation has been performed including direct and indirect energy inputs of all technological operations from soil preparation to anaerobic digestion. The schemes of anaerobic digestion for three types of grass treatment technologies have been designed. It is determined that emissions of direct energy input during the digestion grass silos and fresh grass - 0.049 and 0.041 kgCO 2 per kg of biomass were the highest. The highest gas leakage was found to be in the dried grass digestion case - 0.0241 kgCO 2 per kg of biomass. The ratio of reduction of greenhouse gas emissions was the highest for the dried grass digestion to biogas - 4.55 kgCO 2 per kg of biomass. The results of the analysis of the total energy input for plant biomass anaerobic digestion and energy potential of biomass shows that the energy conversion efficiency of biogas production is the highest at the dried grass (6.8) technology, and the lowest at fresh grass - 5.5. These results suggest that anaerobic digestion to biogas is an energy efficient and environment friendly way of biomass utilization and renewable energy creation.