BIOGAS PRODUCTION POTENTIAL FROM AGRICULTURAL RESIDUES IN LATVIA

It is needed to evaluate the biogas and energy potential from different biomass, including manure, wastewater sludge, energy plants, and food and biofuel processing waste in Latvia. Biogas output from different biomass was investigated in laboratory scale digesters operated at 38 degrees C. Biomass mixed with inoculums (fermented cow manure) was investigated for biogas production in fifteen digesters, operated in batch mode at temperature 38 +/- 1.0 degrees C. Average methane yield per unit of dry organic matter added (dom) from ryegrass silage was 316 l.kg(dom)(-1) and average methane (CH4) content was 58.36 %. Average methane yield from oat middlings was 244 l.kg(dom)(-1) and average methane content was 60.72 %. Average methane yield from jam was 728 l.kg(dom)(-1) and average methane content was 62.77 %. All investigated biomass can be successfully cultivated for energy production in Latvia.