Processing of plant biomass harvested at trace element-contaminated sites managed by gentle (phyto) remediation options

Depending on the GRO (phytoextraction, in situ immobilization and aided phytostabilization) set up on a polluted site and the type of plant used, harvested plant parts may contain concentrations of trace elements (TE) that may be higher than those found in similar vegetation grown on uncontaminated soils (background). To render such technologies economically attractive and feasible, harvested biomass should be valuable and enter valuation pathways. On contaminated lands, plants may serve to provide feedstocks for bioenergy, nonfood products and biofuels and, thus, may contribute to achieve the EU aim by 2020, i.e. to get 20% of its energy from renewable sources. As a potential advantage, these plants will not compete with plants grown on uncontaminated lands as contaminated lands are not suitable for food production. In GREENLAND (http://www.greenland-project.eu/), one task aimed at testing various conventional and innovative technologies of biomass valorisation, such as combustion, anaerobic digestion, pyrolysis and solvolysis, and determining the fate of the TE in the resulting products of each conversion process. Assays were carried out on a wide range of plant species cultivated at the field trials of the GREENLAND partners