Control of acid mine drainage from partly oxidised polymineralic mine wastes using phosphate coatings
Harris, D.L., and Lottermoser, B.G. (2003) Control of acid mine drainage from partly oxidised polymineralic mine wastes using phosphate coatings. In: Sixth International Conference on Acid Rock Drainage (ICARD), pp. 1039-1042. From: ICARD Sixth International Conference on Acid Rock Drainage, 12-18 July 2003, Cairns, Queensland, Australia.
Phosphate induced stabilisation has been used to create passive iron phosphate coatings on pyrite and pyrrhotite. The formation of solid phosphate coatings on sulfide grains thereby inhibits sulfide oxidation. The aims of the study were to determine whether phosphate induced stabilisation could control sulfide oxidation and metal mobility in partly oxidised, polymineralic, sulfidic mine wastes. Waste materials were obtained from the acid mine drainage generating, abandoned Montalbion silver mine site, far north Queensland, Australia. The waste consists of quartz, kaolinite/illite, sulfide minerals (galena, chalcopyrite, tetrahedrite, sphalerite, pyrite, arsenopyrite), and pre- and post-mining oxidation products (hydrated Fe, Cu, Pb and alkali mineral salts). SEM observations of waste material treated with potassium orthophosphate showed that metal, metal-alkali and alkali phosphate coatings developed on all sulfides (with the exception of tetrahedrite). The abundance of phosphate phases was dependant on the availability of cations in solution for complexation with the phosphate anion. In turn, the release of cations was dependent on sulfide oxidation or the dissolution of efflorescent mineral salts. Experiments aiming to dissolve these phosphate coatings – using a strongly oxidising solution – showed that the phosphate coatings remained stable, preventing acid generation and metal release. The results of this study demonstrate that liquid phosphate stabilisers can suppress sulfide oxidation and immobilise metals in partly oxidised, polymineralic mine wastes.
|Item Type:||Conference Item (Refereed Research Paper - E1)|
The theme of the "ICARD Sixth International Conference on Acid Rock Drainage" is "Application and Sustainability of Technologies."
|Date Deposited:||13 Jul 2009 04:27|
|SEO Codes:||96 ENVIRONMENT > 9612 Rehabilitation of Degraded Environments > 961208 Rehabilitation of Degraded Urban and Industrial Environments @ 100%|
Last 12 Months: 2