| Přispěvatelé: |
Li, J, Gerson, AR, Smart, RStC, Kaplun, K, Kawashima, N, Fan, R, Schumann, RC, Hughes, A, Hutchison, B, Kent, S, 8th Australian Acid and Metalliferous Drainage workshop (8th AMD) Adelaide, South Australia 29 April-2 May 2014 |
| Popis: |
At Savage River in Tasmania, the alkaline (non-acid forming) chlorite calcite schist (A-type rock) is one of the waste rock products of Grange Resources magnetite mining operations. The A-type waste rock has been used successfully as side covers and alkaline flow-through materials to alleviate serious AMD from the legacy (sulfide containing) B-dump. The Old Tailings Dam is also a historic AMD site at Savage River. Its seepage is commonly associated with low pH (≈2.6) and responsible for ≈50% of the total mine site acidity load. In this study, the A-type rock was fully characterised and then utilised in a laboratory flowthrough system to treat acidic waters from the Old Tailings Dam. Such a flow-through system has the potential for low cost AMD management at the site. It was found that, at the fixed flow rate of 3 L/kg/day, the waste can effectively raise the seep water pH from 2.6 to near neutral (pH 7-8) with a loading of 157 L/kg. The concentrations of dissolved Al, Cu and Fe were decreased by almost 100 %. Changes in the neutralising behaviour of the waste, in particular, shifting neutralisation from dissolution of carbonates to silicates after 60 days of treatment was observed and is discussed in detail in the paper. Refereed/Peer-reviewed |
