ORGANINĖS APKROVOS ĮTAKA ŽOLINIŲ AUGALŲ BIOMASĖS ANAEROBINIO PERDIRBIMO ENERGETINIAMS RODIKLIAMS.

Cellulose and lignin are heavily degrading materials therefore biomass retention time in the digester has to be prolonged. At the same time the raw substrate outflow from the digester is reduced. The purpose of the paper is to analyse volumetric organic load influence on energetic ratios of anaerobic digestion of perennial grass silage. Three different perennial grasses - cocksfoot grass (Dactylis glomerata), tall fescue (Festuca arundinacea) ir reed canary (Phalaris arundinacea) have been analysed. It is determined that increasing the organic load from 1,0 up to 2,0 kg m-3 d-1 the biogas yield from perennial grasses has a tendency to decrease. The highest variation was for cocksfoot grass case when biogas yield decreased from 550 liters down to 365 liters from kilogram dry matter. The best energy ratios is at 1,0 kg m-3 d-1 organic load and the highest methane concentration as well. The lowest methane concentration -- 49,7 % was at 1,5 kg m-3 d-1 organic load. The energetic value at 1,0 kg m-3 d-1 organic load was the highest -- 12,5 MJ from kilogram dry organic material. [ABSTRACT FROM AUTHOR]