Prospects for the utilization of the Miscanthus giganteus and Polygonum sachalinense for solid biofuel production in the Republic of Moldova

Abstract

Energy production from renewable sources plays an important role. To determine crops which are the most suitable for energy production, its thermophysical properties, ecological impact and production economy must be investigated thoroughly. The hybrid Miscanthus giganteus and the cultivar Gigant of Polygonum sachalinense, which were cultivated in the experimental plot of the Botanical Garden (Institute) of the ASM, served as object of study, control variant – wheat straw Triticum aestivum. It has been established that stems of Polygonum sachalinense stems defoliated and dehydrated faster than Miscanthus giganteus, the bulk density of the chopped material 181 kg/m3 and 146 kg/m3 , respectively. Wheat straw is characterized by the lowest bulk density (83 kg/m3 ). The specific density of briquettes made from milled chaffs (20 mm and 10 mm) of Polygonum sachalinense reaching values 799-841 kg/m3 , Miscanthus giganteus 869-882 kg/m3 , but Triticum aestivum 733-740 kg/m3 . The Polygonum sachalinense and Miscanthus giganteus biomass were distinguished high gross calorific values (19.3-19.8 MJ/kg) and moderately ash content (2.23-2.51%), but wheat straw low calorific value (17.0 MJ/kg) and high content of ash (5.08%).