The sources of renewable energy have acquired considerable interest in recent years, at global and national level. The investigation of introduced herbaceous plant species for further processing into diverse types of bio fuels is an important objective. We investigated the biochemical composition and some thermo physical properties of the biomass of local varieties of non native perennial herbaceous plant species: Energo of Sida hermaphrodita and Gigant of Polygonum sachalinense, created and cultivated in the Botanical Garden (Institute) of the Academy of Sciences of Moldova, maize (Zea mays) – control variant. It has been established that the gas forming potential of digestible organic dry matter from the green mass substrate of the studied perennial species varied from 454 to 460 l/kg and 451-458 l/kg – of silage substrate; in maize substrate – 536 l/kg and 557 l/kg. Polygonum sachalinense substrate had higher content of methane (54.6 %) and methane production potential (4000-4850 m3/ha). The biomass of the studied perennial species was characterized by high bulk density (172-225 kg/m3) and gross calorific value (18.7-19.3 MJ/kg) and reduced ash content (1.5-2.6 %), but maize stalks – by low bulk density (152 kg/m3) and calorific value (17.9 MJ/kg) and high content of ash (4.6 %); the gross calorific value, as a solid fuel, accounted 350-435 GJ/ha. The dry biomass of local varieties was characterized by high content of cellulose (511-535 g/kg), hemicellulose (256 -307g/kg), pentose sugars (91-96 g/kg) and hexose sugars (47-51 g/kg), in comparison with maize stalks (417 g/kg; 250 g/kg; 75 g/kg and 41 g/kg). The theoretical ethanol potential was 19-26 % higher and constituted 557-614 l/t dry matter. The obtained results indicate the possibility of using the local varieties Energo of Sida hermaphrodita and Gigant of Polygonum sachalinense for the creation of plantations to produce biomass energy for multiple purposes in Moldova.

biochemical composition, bio methane, pellets, Polygonum sachalinense, Sida hermaphrodita, theoretical ethanol potential, thermo physical properties

field crops and pastures

Presentation: oral