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Open Pit Mine Planning: Analysis and system modeling of conventional and oil sands applicationsThorley, URSULA 04 October 2012 (has links)
In the last decade mineable oil sands production in Canada has grown rapidly. Constraints on the planning and design processes employed by surface mining oil sands operations vary in distinct ways from other commodities mined by both hard and soft rock open pit methods. The unique waste handling needs, including tailings disposal, of contemporary oil sands mining requires specific planning considerations.
It is the purpose of this research to analyze and document a conventional hard rock, metal mine planning system, and contrast this with the unconventional mine planning system used by oil sands mines. Systems activity models of both the conventional and unconventional systems are developed in support of documenting and contrasting the two systems.
Constraints unique to oil sands mine planning are identified and their impact on the oil sands mine planning system are documented. The impacts of challenging waste handling and storage requirements and a uniquely prescriptive regulatory environment defining mineable ore are identified as key constraints.
The research concludes with a proposal for a new planning system to better support the planning of oil sands mines. The proposed system respects the unique waste management considerations in oil sands planning and revisits the current regulatory approach to ensuring resource recovery. The proposed system is compatible with traditional approaches to economic analysis in open pit planning, and with emerging best practices to manage technical and economic uncertainty, improve project optimization, and develop robust mine plans. / Thesis (Ph.D, Mining Engineering) -- Queen's University, 2012-10-02 17:52:18.223
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Late Pleistocene lithic technological organization on the southern Oregon coast : investigations at Indian Sands (35-CU-67C)Willis, Samuel C. 11 March 2005 (has links)
Excavations conducted at Indian Sands (35-CU-67C), located along Oregon's
southern coast, during 2002 and 2003 identified two discreet, artifact-bearing stratigraphic
units. The uppermost unit is a deflated surface containing burnt shell and lithic artifacts
associated with early Holocene ¹⁴C dates, while the underlying unit contained only lithic tools
and debitage, some of which were associated with a ¹⁴C date of 10,430 ± 150 RCYBP. The
late Pleistocene lithic assemblage at 35-CU-67C provides the earliest evidence for human
presence on the Oregon coast to date. Analysis performed on the late Pleistocene
assemblage addresses the validity of existing hypotheses regarding the nature of early
Oregon coastal hunter-gatherer technological and subsistence strategies. These
hypotheses are focused on whether early populations on the Oregon coast practiced a
generalist-forager or collector subsistence strategy.
Using theoretical approaches that deal with the organization of hunter-gatherer
technology, analyses were conducted on the lithic tool and debitage assemblages at 35-CU-
67C in order to infer past hunter-gatherer behavior. Through the implementation of multiple
tool and debitage analysis methodologies, issues of hunter-gatherer mobility, raw material
procurement, stages of lithic reduction, tool production, and site function are presented. The data generated by the late Pleistocene lithic assemblage at 35-CU-67C are compared with
the overlying surficial assemblage, additional early sites along the North American Pacific
coast, and to contemporaneous sites located further inland within the Pacific Northwest
region.
Results of the lithic analyses at 35-CU-67C show distinct similarities in debitage trends
between the assemblages of each stratigraphic unit. However, when tool assemblages from
these units are compared, discrepancies in the types and amount of tools are found.
Reasons for intra-site variability and similarity are explained through raw material studies
and site function at 35-CU-67C. Additionally, similarities between the early tool assemblage
at 35-CU-67C and those found in early tool assemblages on the extended Pacific coast and
interior Pacific Northwest regions are discussed.
This thesis demonstrates that early southern Oregon coastal populations had a tendency
towards high mobility and used a generalized toolkit organization. Early lithic technology
used at 35-CU-67C emphasized multidirectional core technology and biface manufacture in
the form of preforms and leaf-shaped projectile-points. This type of technological
organization is to be expected from hunter-gatherers practicing a generalist-forager
subsistence strategy. Based on the 10,430 ± 150 RCYBP date and technological
organization at 35-CU-67C, early Oregon coastal occupation is seen as encompassing a
generalist-forager subsistence strategy most likely adapted to both coastal and terrestrial
environments. / Graduation date: 2005
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Fundamentals of SegregationMihiretu, Yetimgeta 11 1900 (has links)
A common challenge during deposition of slurries is segregation as large particles settle through the matrix of fines and water. Whether segregation occurs or not depends on the grain size distribution of the solids, the void ratio or solids content and the rheological properties of the fines-water matrix.
The rheological characterization of slurry composed of different grain sizes and varying water chemistry was investigated. The vane yield stress was used to characterize different slurries composed of clay, silt and sand materials. Semi-empirical fractal theory showed good agreement with experimental data for fine slurry. Comparison of yield stress at same concentration but different composition showed a decreasing trend as the composition of either silt or sand material increases. The pore-water effect was studied for representative kaolinite slurry. The yield stress was insensitive for pH values in the acidic and neutral range, while in the basic range it showed significant response depending upon the type of the chemical used to achieve the pH: Ca(OH)2 and NaOH.
A modified segmented standpipe was designed and used in a series of experiments to determine concentration profiles during the sedimentation processes. Analyses of the solid content profiles and sand content profiles in the standpipes indicated a capture of sand particles which could be correlated to the yield stress of the fines matrix. Theoretical calculations, however, showed over-prediction of the captured sand size. A correction factor of about 0.2 was applied.
Flume test on a high solid content slurries showed that the dynamic segregation is governed by all the factors governing the static case. Beaching profile shapes were not a necessary indication of segregating and non-segregating type of slurries. Modified version plastic theory for flow slides was used to characterise profile shape.
Computational fluid dynamics approaches based on kinetic theory and bi-viscous model analysis were implemented and showed a reasonable capability in modelling segregation when compared with experimental results. A statistical formulation for segregation index, SI, was proposed. The index accounts for variation in depth of samples. Finally recommendations for future research are proposed based on the observations and findings made from the study. / Geotechnical Engineering
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Study of bubble-flat surface interactionsSeyyed Najafi, Aref 06 1900 (has links)
Canada has the largest known reserve of oil in the world in the form of oil sands: an estimated 1.7 to 2.5 trillion barrels of oil are deposited in combination of the sand, water and clay.
The presented research is devoted to bubble-solid surface interaction, which is one of the critical areas of the oil sand processing and it is also a key point for many other processing technologies, such as mineral recovery, froth flotation, soil remediation, de inking of paper, heat transfer in boilers tube, biological and medical sciences.
The goal of this work was to investigate new theoretical and practical approaches, which would help in better understanding of fundamentals of the flotation process in oil sands extraction. Among many achievements of this research are:
1)development of the method for generation of a single micro bubble. Dependence of this process on micropipette tip size and inclination, gas type, taper length and other parameters has also been studied (Chapter 3);
2)study of gas bubble - flat surface interactions based on a practical approach of determination of two dynamic parameters, sliding velocity and induction time of a gas bubble. Various types of gas bubbles (CO2, Air, H2, and O2) and collector surfaces (bitumen, treated hydrophobic and hydrophilic silica) were used in sliding velocity and induction time measurements. The sliding velocity of gas bubbles under an inclined collector surface was found to be in a strong dependence of water chemistry, type of gases, temperature, initial separation between bubble and collector surface (Chapter 4);
3)developing an analytical model for predicting bubble sliding velocity based on previously developed models. The model was in a good agreement with experimental results (Chapter 5);
4)establishing a new method for bubble zeta potential measurements. The measurements were in a good agreement with previously studies reported in literature (Chapter 6).
Summarized above findings from this research represent valuable advances in understanding oil sands processing. The prospects of future work are provided in Chapter 8. / Chemical Engineering
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Co-gasification of biomass with coal and oil sands coke in a drop tube furnaceGao, Chen 11 1900 (has links)
Chars were obtained from individual fuels and blends with different blend ratios of coal, coke and biomass in Drop Tube Furnace at different temperatures. Based on TGA experimental data, it was shown that the effect of the blending ratio of biomass to other fuels on the reactivity of the co-pyrolyzed chars is more pronounced on the chars prepared at lower temperature, due to the presence of synergetic effects originating from the interaction of the two fuels.
SEM images showed differences in shapes and particle size of char particles from biomass and coal/coke. These also show the agglomeration of coal and coke chars with biomass char particles at high temperatures. The agglomeration may be the reason for the non-additive behavior of the blends. BET analysis showed increase in the surface area with an increasing temperature for biomass and coal, but the trend for coke was inversely related to the temperature. / Chemical Engineering
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Impact of Solvents Treatment on the Wettability of Froth SolidsYang, Fan 11 1900 (has links)
The purpose of this study is to investigate the impact of solvent addition to bitumen froth on the wettability of froth solids. The wettability of solids determines the transportation/partitioning of the solids between phases, which in turn affects the solids and water rejection in a Clark hot water extraction process (CHWE).
The impact of solvents treatment on the wettability of froth solids was studied using both a model system and a real bitumen froth system. The vulnerabilities of four kinds of model minerals to hydrocarbon contamination/wettability alteration in different solvents were compared and discussed by considering solvent composition and mineral types.
The wettability of solids extracted from the industrial froth using different solvents was also compared. The XRD analysis on these solids confirmed the partitioning behavior of solids observed in model solids system.
The results from this study indicate that the composition of paraffinic/aromatic solvent in an industrial froth treatment process could be tailor-optimized to achieve a better solids/water rejection. / Materials Engineering
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Examining the growth and stable isotopes of phytoplankton and periphyton communities exposed to oil sands reclamation strategiesBoutsivongsakd, Monique January 2013 (has links)
The impacts of oil sands processed materials (OSPM) on phytoplankton and periphyton community growth and stable carbon and nitrogen isotopes were examined. Estimates of plankton and periphyton community growth, measured as chl a and dry weight, were low and similar in reference and OSPM reclamation wetlands. The use of stable isotope analyses revealed higher δ15N of plankton and periphyton in OSPM wetlands than reference wetlands, possibly due to increased TN concentrations in some OSPM wetlands.
In the laboratory, water-soluble fractions (WSF) of two types of OSPM (mature fine tailings, MFT and consolidated tailings, CT) and an amendment material (peat-mineral mixture), potential fill materials in wetland or end pit lake reclamation, were examined for phytoplankton community growth and stable carbon and nitrogen isotopes. All WSF treatments had higher chl a compared to reference water and maximum growth was observed at a 50:50 ratio of peat:CT or peat:MFT. In general, WSFs of peat had the highest concentration of total nitrogen (TN) whereas WSFs of MFT had the highest total phosphorus (TP; 3x higher). The results suggested that the addition of peat as an amendment to OSPM (particularly for MFT), contributing additional TN, could improve phytoplankton community growth in oil sands reclamation. At higher percentages of MFT WSF, there was increased turbidity due to fine clay particles that likely contributed to reduced phytoplankton growth. Turbidity could be an important factor limiting phytoplankton growth and thus reducing dietary resources and biological detritus (via sedimentation) in the initial development of an end pit lake. The WSFs also promoted the unfavourable growth of filamentous algae, highest at intermediate concentrations of peat and CT WSFs and inhibited in MFT WSFs due to light limitation. Stable N isotopes of plankton and filamentous algae suggests that 15N enrichment of algae could be a useful indicator of nutrient inputs, including OSPM seepage into natural aquatic systems, for oil sands regional monitoring programs.
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Study on the Role of a Cationic Organic Dispersant in Bitumen Recovery from Mineable Oil Sands OresTseng, Henry Unknown Date
No description available.
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Health assessment of tree swallows (<i>tachycineta bicolor</i>) nesting on the Athabasca Oil Sands, AlbertaGentes, Marie-Line 08 February 2007
Oil sands mining companies in Alberta, Canada, are planning to create wetlands for the bioremediation of mining waste materials as part of a reclamation strategy. To assess feasibility, experimental wetlands mimicking proposed reclamation scenarios were constructed on mining leases. This research assessed the health of tree swallows (<i>Tachycineta bicolor</i>) nesting on these sites where they were naturally exposed to a mixture of chemicals including unrecovered bitumen, naphthenic acids (NAs) and polycyclic aromatic hydrocarbons (PAHs). Endpoints reflecting health were compared among three experimental wetlands and one reference site. In order to specifically investigate toxicity of NAs to birds, an experimental exposure to NAs was also conducted on a subset of nestlings on the reference site. <p> In 2003 and 2004, approximately 50 breeding pairs (total, per year) nesting on the following sites were monitored: Suncors Consolidated Tailings and Natural Wetlands; Syncrudes Demo Pond and Poplar Creek reference site. In 2003, reproductive success was very low on OSPM-sites compared to the reference site, but was relatively unaffected in 2004. Compromised reproductive performance in 2003 was linked to harsh weather, during which mortality rates of nestlings reached 100% on the site with the highest levels of PAHs and NAs, while they did not surpass 50% on the reference site. In 2004, mortality rates were low but nestlings from OSPM-sites weighed less and showed greater hepatic detoxification efforts (etoxyresorufin-o-deethylase activity) than those on the reference site. Furthermore, nestlings on OSPM-sites exhibited higher levels of thyroid hormones and suffered parasitic burdens (Protocalliphora spp.) approximately twice that of those on the reference site. Several of these findings may be associated with low post-fledging survival, suggesting that wet landscape reclamation strategy is not optimal for avian species and may require improvement. <p> As part of a separate study investigating toxicity of naphthenic acids, twenty nestlings from the reference site were randomly selected for an experimental exposure. Nestlings received 0.1 ml/day of NAs (15g/L) orally from day 7 to day 13 of age while being reared normally by their free-ranging parents. Nestling growth, hematocrit, blood biochemistry, organ weights and etoxyresorufin-o-deethylase activity (EROD) activity appeared unaffected by naphthenic acids. No toxic changes were detected on histopathological evaluation of major organs. These findings suggest that for nestlings reared on oil sands reclaimed sites, exposure to other chemicals such as polycyclic aromatic hydrocarbons is a greater concern than exposure to NAs. However, this study did not investigate the chronic or reproductive toxicity of naphthenic acids. More research still needs to be conducted as a part of an assessment of the sustainability of wet landscape reclamation because a previous study found that chronic exposure to NAs severely compromised reproduction in mammals.
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<i>In-situ</i> caged wood frog (<i>Rana sylvatica</i>) survival and development in wetlands formed from oil sands process-affected materials (OSPM)Hersikorn, Blair Donald 12 March 2009
Currently there are three companies producing bitumen from the Athabasca Oil Sands Region located near Fort McMurray, Alberta, Canada. Extraction of bitumen produces solid (sand) and liquid (water with suspended fine particles) tailings material, called oil sands process affected-materials (OSPM). These waste materials are stored on site due to a zero discharge policy and must be reclaimed when operations end. The OSPM is known to contain naphthenic acids (NAs) and polycyclic aromatic hydrocarbons (PAHs) and has high pH and salinity. A possible method of reclamation is the wet landscape approach, which involves using OSPM to form wetlands that would mimic natural wetland ecological functioning. This study investigated the effects of wetlands formed with OSPM on wood frog larvae (<i>Rana sylvatica</i>), using endpoints including survival, growth, time to metamorphosis, hormonal status, and detoxification enzyme induction [ethoxyresorufin-o-dealkylase (EROD) activity].<p>
<i>In-situ</i> caging studies were completed in 2006 and 2007. Four wetlands were studied in 2006 and 14 wetlands were studied in 2007. The 2006 season saw a host of problems that were resolved for the 2007 season. In 2006, tadpole survival did not differ among reference wetlands and old OSPM-affected wetlands but there was 100% mortality of tadpoles in the young OSPM-affected sites that contain the highest concentration of toxic components. Results were similar in 2007, with tadpoles raised in young OSPM-affected wetlands having 41.5%, 62.6%, and 54.7% higher tadpole mortality than old OSPM-affected, young reference, and old reference wetlands, respectively. In 2007, tadpoles from young OSPM-affected sites had delayed metamorphosis (12 days longer than tadpoles from old reference wetlands and 18 days longer than tadpoles in old OSPM-affected wetlands). The thyroid hormone ratios of tadpoles in young OSPM-affected wetlands were between 25% and 42% lower than tadpoles in all other wetlands groups. The EROD activity of tadpoles in young OSPM-affected wetlands was an average 223% higher than those in old OSPM-affected wetlands, showing us that tadpoles were responding to higher levels of contaminants in young OSPM-affected wetlands. Size differences were only noted in 2007, most likely not as a result of exposure to OSPM, but due to differences in population density. The results of this study lead us to believe that toxicity due to OSPM decreases as wetlands get older and OSPM-affected wetlands could support native amphibian populations if they are allowed to mature. Since we considered wetlands to be old if they were seven years or older and the fact that old-OSPM wetlands showed effects on tadpoles similar to those of reference wetlands and showed much less toxicity than young OSPM-affected wetlands, we believe wetlands that are at least seven years old would sustain amphibian life.
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