Biomass quality of some Asteraceae species for solid biofuel purposes in Moldova

In the latest years, the rapid changes in global climate, such as the depletion of fossil fuel resources, have motivated an increasing interest in renewable energy production, and phytomass represents a good opportunity. The purpose of this research was to evaluate some biological features, physical and mechanical characteristics of the dry biomass of the Asteraceae species: Artemisia annua, Artemisia absinthium, Helianthus annuus and Helianthus tuberosus from the experimental land of the Botanical Garden (Institute), control variants – wheat straw, Triticum aestivum. The physical and mechanical characteristics of dry biomass were determined according to the European Standards at the State Agrarian University of Moldova, the production of solid fuels – by the equipment developed at the Institute of Agricultural Technique “Mecagro”, Chişinău. It was determined that the biomass productivity reached 0.72 – 0.93 kg/m2 of Artemisia annua, 0.90-1.31 kg/m2 of Artemisia absinthium and 2.53-2.80 kg/m2 ofHelianthus tuberosus.It was established that the stems of Helianthus tuberosusdefoliated faster than Artemisia annua and Artemisia absinthium. The bulk density of the milled chaffs varied from 118 kg/m3 to 188 kg/ m3. The biomass of Asteraceae species was distinguished by high gross calorific value (18.9-19.7 MJ/kg) and moderate ash content (2.1-3.5%). The specific density of briquettes made of biomass of Asteraceae species reached values of 800-911 kg/m3, but the bulk density of briquettes – 423-472 kg/m3. The cultivation and the harvest of these species do not require special farm machinery.