|
|
Chalaturnyk, R. J., Scott, J. D., & Ozum, B. (2002). Management of Oil Sands Tailings. Pet. Sci. Technol., 20(9-10), 1025–1046.
Abstract: In Alberta, oil sands bitumen is utilized for synthetic crude oil (SCO) production by surface mining, bitumen extraction followed by primary (coking) and secondary (catalytic hydro-treating) upgrading processes. SCO is further refined in specially designed or slightly modified conventional refineries into transportation fuels. Oil sands tailings, composed of water, sands, silt, clay and residual bitumen, is produced as a byproduct of the bitumen extraction process. The tailings have poor consolidation and Water release characteristics. For twenty years, significant research has been performed to improve the consolidation and water release characteristics of the tailings. Several processes were developed for the management of oil sands tailings, resulting in different recovered water characteristics, consolidation rates and consolidated solid characteristics. These processes may affect the performance of the overall plant operations. Apex Engineering Inc. (AEI) has been developing a process for, thesame purpose. In this process oil sands tailings are treated with Ca(OH)(2) lime and CO2 and thickened using a suitable thickener. The combination of chemical treatment and the use of a thickener results in the release of process water in short retention times without accumulation of any ions in the recovered water. This makes it possible to recycle the recovered water, probably after a chemical treatment, as warm as possible, which improves the thermal efficiency of the extraction process. The AEI Process can be applied in many different fashions for the management of different fractions of the tailings effluent, depending on the overall plant operating priorities.
|
|
|
|
Brown, M., Barley, B., & Wood, H. (2002). Minewater Treatment – Technology, Application and Policy. London: IWA Publishing.
Abstract: Much work has been carried out in recent decades concerning minewater treatment, both in the UK and worldwide. Many different bodies and organizations are involved in developing minewater treatment processes and schemes. Minewater Treatment addresses the need for a single source of state-of-the-art information that draws all the latest research material together. Key features of the book include: a full literature review of minewater treatment throughout the world; an overview of relevant legislation and policy in a global context; a review of currently available methods for treating minewater worldwide; a site specific inventory of minewater treatment schemes within the UK, including compilation of available monitoring data and assessment of performance; a review of emerging and innovative minewater treatment technologies and consideration of related academic research within the UK; a comprehensive list of active and innovative minewater treatment technologies that are not currently compiled in a book or other review publication; a detailed summary and recommendations section assessing the applicability, efficiency and cost-effectiveness of minewater treatment schemes. Relevant scientific subject matter is presented in a concise, easily accessible manner to assist with the objective assessment of the progress made to date. Heavily illustrated with many colour photographs, the book allows best use to be made of the collective experience of minewater treatment practitioners throughout the UK, whilst at the same time placing the UK experience within a global context. An invaluable reference work for mining companies, consultants, planning officers, environmental research scientists, environmental agencies, water utilities and regulatory bodies, Minewater Treatment is a definitive source of information on minewater treatment technologies and will help facilitate the selection of the most appropriate technique required to tackle particular minewater discharge problems. Contents 1. The mine water problem 2. Treatment options 3. Existing sites in the UK: Case studies 4. Existing sites in the UK: Site summaries 5. Summary & conclusions
|
|
|
|
Brown, M., Barley, B., & Wood, H. (2002). Minewater treatment; technology, application and policy. London: IWA Publishing.
|
|
|
|
Bloom, N. S., Preus, E., Kilner, P. I., von der Geest, E., & Hensman, C. E. (2002). Very efficient removal of toxic metals from acid mine drainage water (Berkeley Pit, Montana) with a recycled alkaline industrial waste product Hardrock mining 2002; issues shaping the industry..
|
|
|
|
Arango, I. (2002). Evaluation of the beneficial effects of the acidophilic alga Euglena mutabilis on acid mine drainage systems. Ph.D. thesis, Indiana State University,, Terre Haute.
Abstract: Euglena mutabilis is an acidophilic, photosynthetic protozoan that forms benthic mats in acid mine drainage (AMD) channels. At the Green Valley mine, western Indiana, E. mutabilis resides in AMD measuring <4.2 pH, with high concentrations of dissolved constituents (up to 22.67 g/l). One of the main factors influencing E. mutabilis distribution is water temperature. The microbe forms thick (>1 mm), extensive mats during spring and fall, when water temperature is between 13 and 28 degrees C. During winter and summer, when temperatures are outside this range, benthic communities have a very patchy distribution and are restricted to areas protected from extreme temperature changes. E. mutabilis also responds to rapid increases in pH, which are associated with rainfall events. During these events pH can increase above 4.0, causing precipitation of Fe and Al oxy-hydroxides that cover the mats. The microbe responds by moving through the precipitates, due to phototaxis, and reestablishing the community at the sediment-water interface within 12 hours. The biological activities of E. mutabilis may have a beneficial effect on AMD systems by removing iron from effluent via oxygenic photosynthesis, and/or by internal sequestration. Photosynthesis by E. mutabilis contributes elevated concentrations of dissolved oxygen (DO), up to 17.25 mg/l in the field and up to 11.83 mg/l in the laboratory, driving oxidation and precipitation of reduced metal species, especially Fe (II), which are dissolved in the effluent. In addition, preliminary electro-microscopic and staining analyses of the reddish intracellular granules in E. mutabilis indicate that the granules contain iron, suggesting that E. mutabilis sequesters iron from AMD. Inductive coupled plasma analysis of iron concentration in AMD with and without E. mutabilis also shows that E. mutabilis accelerates the rate of Fe removal from the media. Whether iron removal is accelerated by internal sequestration of iron and/or by precipitation via oxygenic photosynthesis has yet to be determined. These biological activities may play an important role in the natural remediation of AMD systems.
|
|
