TY - JOUR
T1 - Productive use of steelmaking by-product in environmental applications - II
T2 - Leachate geochemistry, ecotoxicity and environmental radioactivity
AU - Wendling, L. A.
AU - Douglas, G. B.
AU - Coleman, S.
PY - 2012/12/1
Y1 - 2012/12/1
N2 - Detailed laboratory studies have indicated that the HIsmelt steelmaking by-product has the ability to neutralise acidity and hence, may have potential application as an environmental amendment. Prior to widespread environmental use, however, an ecotoxicological characterisation of the by-product leachate and an environmental radioactivity risk assessment are required. Ecotoxicity testing indicated that the HIsmelt steelmaking by-product softwater leachate, adjusted from its natural pH of 10.6-8.0 prior to use, was of low toxicity to Chlorella algae and the marine bacterium Vibrio fischeri, and not toxic to the cladoceran Ceriodaphnia dubia. Leachate metal concentrations in HIsmelt by-product were low. Relative to stringent health-based guidelines for Australian drinking water, the HIsmelt softwater leachate only exceeds the pH guideline of 6.5-8.5. The acidic toxicity characteristic leaching procedure (TCLP) HIsmelt leachate compares favourably with TCLP leachates from international steel-making by-products with low trace element concentrations reflecting low solid-phase concentrations. The HIsmelt steelmaking by-product exhibited low to moderate U and Th decay chain radionuclide activities with an absorbed dose rate of 65 nGy/h. Given the low ecotoxicity, low leachate trace elements concentrations and acceptable radioactivity, the HIsmelt steelmaking by-product has potential applications as a construction material or as a soil amendment to ameliorate acidity. However, based on the results of the synthetic softwater leachate tests, it is likely that the HIsmelt steelmaking by-product will require mixing with other materials to reduce leachate pH prior to use as an environmental amendment.
AB - Detailed laboratory studies have indicated that the HIsmelt steelmaking by-product has the ability to neutralise acidity and hence, may have potential application as an environmental amendment. Prior to widespread environmental use, however, an ecotoxicological characterisation of the by-product leachate and an environmental radioactivity risk assessment are required. Ecotoxicity testing indicated that the HIsmelt steelmaking by-product softwater leachate, adjusted from its natural pH of 10.6-8.0 prior to use, was of low toxicity to Chlorella algae and the marine bacterium Vibrio fischeri, and not toxic to the cladoceran Ceriodaphnia dubia. Leachate metal concentrations in HIsmelt by-product were low. Relative to stringent health-based guidelines for Australian drinking water, the HIsmelt softwater leachate only exceeds the pH guideline of 6.5-8.5. The acidic toxicity characteristic leaching procedure (TCLP) HIsmelt leachate compares favourably with TCLP leachates from international steel-making by-products with low trace element concentrations reflecting low solid-phase concentrations. The HIsmelt steelmaking by-product exhibited low to moderate U and Th decay chain radionuclide activities with an absorbed dose rate of 65 nGy/h. Given the low ecotoxicity, low leachate trace elements concentrations and acceptable radioactivity, the HIsmelt steelmaking by-product has potential applications as a construction material or as a soil amendment to ameliorate acidity. However, based on the results of the synthetic softwater leachate tests, it is likely that the HIsmelt steelmaking by-product will require mixing with other materials to reduce leachate pH prior to use as an environmental amendment.
KW - Environmental
KW - Iron ore
KW - Mineral processing
UR - http://www.scopus.com/inward/record.url?scp=84867046407&partnerID=8YFLogxK
U2 - 10.1016/j.mineng.2012.07.010
DO - 10.1016/j.mineng.2012.07.010
M3 - Article
AN - SCOPUS:84867046407
SN - 0892-6875
VL - 39
SP - 219
EP - 227
JO - Minerals Engineering
JF - Minerals Engineering
ER -