Biomass Ashes for Acid Mine Drainage Remediation

Abstract

Acid mine drainage (AMD) is the largest environmental problem facing the world mining and processing industry because it has low pH and can contain high concentrations of potential pollutants. Biomass ash (BA) can be considered as a potential material for AMD treatment. The main goal of this work was to investigate potential use of Biomass ash of CPK-LA and PK-LA types for AMD remediation. Four UK BAs from different fuels (i.e. straw, meat and bone meal, poultry litter), synthetic AMD, and raw AMDs (Belovo and Ursk) were used for the AMD treatment experiments. Batch experiments showed that in 1 h the biomass ash from straw combustion can effectively neutralise the synthetic AMD and the Belovo AMD with removal of potential pollutants at the liquid-to-solid ratio (L/S) of 100-250 and 10-50, respectively. The biomass ashes from straw and poultry litter combustion can effectively remove pollutants from the Ursk AMD at L/S 100 and adjust pH. The metal concentrations of those treated AMDs met receiving water quality standards. Potential pollutants precipitated as carbonate/hydroxide/sulphate, co-precipitated with Fe oxyhydroxides and Ca phosphates, and appeared as new phases such as Ca, Cu, Zn phosphates and Ca, Fe phosphates. This investigation is essential for development of appropriate, environmentally friendly and economically rational waste management. Graphic AbstractKeywords Biomass ash · AMD remediation · Industrial water treatment · Straw · Meat and bone meal · Poultry litter Extended author information available on the last page of the article Waste and Biomass Valorization 1 3 Statement of NoveltyThis paper presents novel research on using biomass ashes of CPK-LA and PK-LA types (e.g., straw and animal residue) for acid mine drainage treatment. This study highlights industrial symbiosis that is becoming very important in sustainable development.

Performance Assessment of Wood Ash and Bone Char for Manganese Treatment in Acid Mine Drainage

“…A pH of 8.4-9.0 was essential for Mn to precipitate as oxide and hydroxide during AMD treatment by various biomass ashes [38]. This study supports these findings and shows that Mn removal by WA shifts from insignificant at pH < 6.5 to complete at pH > 9.0 and takes place via Mn(II) sorption and oxidation/precipitation, depending on the pH in the system.…”

“…The shape of the XRD baseline indicates the presence of amorphous solids, while the principal crystalline phases were dicalcium silicate (Sy: Ca 2 SiO 4 ) and fairchildite (F: K 2 Ca(CO 3 ) 2 ). Although calcite is a common component in the bottom biomass ashes [18,38], ash mineralogy is controlled by the relative ratios of the dominant ash-forming cations and reaction temperature. The formation of fairchildite instead of calcite relies on the wood's initial K:Ca ratio [39] and can be associated with a high K content in the WA sample (Table 2).…”

“…As the Mn concentration in the solution increased, raising the WA dose from 0.8 to 1.2 g/L was necessary to reach a final pH value of ~9 (Figure 3b). Given the pH critical for Mn's complete removal by wood ash, it was associated with hydroxide/oxyhydroxide precipitation [38]. An additional increase in the amount of WA can be considered unnecessary and unfavorable from the treated water quality point of view, i.e., high alkalinity.…”