LaPointe, F., Fytas, K., & McConchie, D. (2005). Using permeable reactive barriers for the treatment of acid rock drainage. International journal of surface mining, reclamation and environment, 19(1), 57–65.
Abstract: Acid mine drainage (AMD) is the most serious environmental problem facing the Canadian mineral industry today. It results from oxidation of sulphide minerals (e.g. pyrite or pyrrhotite) contained in mine waste or mine tailings and is characterized by acid effluents rich in heavy metals that are released into the environment. A new acid remediation technology is presented, by which metallurgical residues from the aluminium extraction industry are used to construct permeable reactive barriers (PRBs) to treat acid mine effluents. This technology is very promising for treating acid mine effluents in order to decrease their harmful environmental effects
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Banks, S. B. (2003). The UK coal authority minewater-treatment scheme programme: Performance of operational systems. Jciwem, 17(2), 117–122.
Abstract: This paper summarises the performance of minewater-treatment schemes which are operated under the Coal Authority's National Minewater Treatment Programme. Commonly-used design criteria and performance indicators are briefly discussed, and the performance of wetland systems which are operated by the Coal Authority is reviewed. Most schemes for which data are available remove more than 90% iron, and average area-adjusted iron-removal rates range from 1.5 to 5.5 g Fe/m(2). d. These values, which are based on performance calculations, can be distorted by several factors, including the practice of maximising wetland areas to make best use of available land. Removal rates are limited by influent iron loadings, and area-adjusted iron-removal rates should be used with caution when assessing wetland performance. Sizing criteria for all types of treatment system might be refined if more detailed data become available.
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Juby, G. J. G., & Schutte, C. F. (2000). Membrane Life in a Seeded-slurry Reverse Osmosis System. Water Sa, 26(2), 239–248.
Abstract: Membrane replacement can be a major operating cost of a membrane plant. During the development of a novel desalination technique (the SPARRO process) for treating calcium sulphate scaling mine waters the expected life of tubular cellulose acetate membranes operating in the seeded-slurry mode was investigated.During four operating phases of the plant over a five-year period more than 9 000 h of operating data were obtained. Performance data showed that each operating phase was dominated by either membrane fouling or membrane hydrolysis. Membrane fouling was observed to begin near the front-end of the membrane stack and proceed towards the back. Hydrolysis, on the other hand, occurred first in the tail end of the stack and moved backwards towards the Front end modules. Although two detailed membrane autopsies were carried out no definitive statement can be made in respect of the causes of either membrane hydrolysis or membrane fouling. However, suggestions are presented to explain the observed fouling phenomenon in relation to the turbidity of the pretreated feed water and the presence of chlorine. It is proposed that the presence of radioactive isotopes in the mine water which become concentrated in the process contributes to the observed membrane hydrolysis. A membrane life of up to two years is projected for an improved pretreatment arrangement.
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Burt, R. A., & Caruccio, F. T. (1986). The effect of limestone treatments on the rate of acid generation from pyritic mine gangue. Environmental geochemistry and health, 8, 8.
Abstract: Surface water enters the Haile Gold Mine, Lancaster County, South Carolina by means of a small stream and is ponded behind a dam and in an abandoned pit. This water is affected by acidic drainage. In spite of the large exposures of potentially acid producing pyritic rock, the flux of acid to the water is relatively low. Nevertheless, the resulting pH values of the mine water are low (around 3.5) due to negligible buffering capacity. In view of the observed low release of acidity, the potential for acid drainage abatement by limestone ameliorants appears feasible. This study investigated the effects of limestone treatment on acid generation rates of the Haile mine pyritic rocks through a series of leaching experiments. Below a critical alkalinity threshold value, solutions of dissolved limestone were found consistently to accelerate the rate of pyrite oxidation by varying degrees. The oxidation rates were further accelerated by admixing solid limestone with the pyritic rock. However, after a period of about a month, the pyrite oxidation rate of the admixed samples declined to a level lower than that of untreated pyrite. Leachates produced by the pyrite and limestone mixtures contained little if any iron. Further, in the mixtures, an alteration of the pyrite surface was apparent. The observed behaviour of the treated pyrite appears to be related to the immersion of the pyrite grains within a high alkalinity/high pH environment. The high pH increases the rate of oxidation of ferrous iron which results in a higher concentration of ferric iron at the pyrite surface. This, in turn, increases the rate of pyrite oxidation. Above a threshold alkalinity value, the precipitation of hydrous iron oxides at the pyrite surface eventually outpaces acid generation and coats the pyrite surface, retarding the rate of pyrite oxidation.
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Bochkarev, G. R., Beloborodov, A. V., Kondrat'ev, S. A., & Pushkareva, G. I. (1994). Intensification of Aeration in treating Natural-Water and Mine Water. J. Min. Sci., 30(6), 5.
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