Assessment of the Energy Recovery Potential of Biomass Obtained from Non-Productive Lands in the Jiu Valley, Romania

This work focuses on assessing the potential for energy recovery from biomass obtained from unproductive lands in the Jiu Valley. The main objective of the study is to identify a viable solution for the restoration of degraded land. The research aims to utilise these lands through energy crops; the biomass is then introduced into an anaerobic digestion plant to produce biogas. The novelty of this research consists of the physical transformation of these lands into a living laboratory, intended exclusively for the cultivation and study of biomass. Maize, soybean and sorghum plants were chosen for the study. The biomass was analysed in detail to determine the total solids (TS) and volatile solids (VS) content. In maize, VS ranged from 62.67% by mass to 76.58% by mass. In soybean, VS content was between 35.35% by mass and 36.60% by mass. In sorghum, VS ranged between 35.29% by mass and 38.86% by mass. This research showed that the largest amount of biogas resulted from fresh soybean biomass. Dry biomass, with its high lignin content, significantly reduced the digestion process’s efficiency. The study highlights that it is important to use fresh biomass after an appropriate mechanical pre-treatment to optimise biogas production.