Study of potential availability of heavy metals to phytoremediation to use of ash from biomass combustion

Ashes, formed as a result of combustion of biomass are a new class of by-products of combustion and due to the large variety of these materials their chemical composition has not been fully determined. Their use is limited, despite the fact that their production has increased. This work presents the results of studies on the possibility of limiting the potential availability of Cu, Mn, Pb and Zn for plants by use of an inorganic stabilizer - ash from biomass combustion. In this study the usefulness of ash from biomass for binding mobile fractions of heavy metals (Cu, Mn, Pb and Zn) was evaluated. The investigations were executed using three extraction tests with the use of the following extraction solutions: 1 M HNO3 – acid soluble forms (As), 0.05 M EDTA – bioavailable forms (Bio), 2.5% CH3COOH – exchangeable forms (Ex). The values of the following parameters: Mobility Index (MI), Contamination Factor (CF), Pollution Load Index (PLI), Geo – accumulation Index (Igeo) and Ecological Risk Index (RI) were defined and determined for their suitability as a test soil stabilizer. Furthermore, a multivariate statistical analysis was carried out. It was found, that a phytoremediation process using investigated ash from biomass combustion can be applied to soil contaminated by heavy metals.